Reviewing Common Control Panel Functions

Reviewing Common Control Panel Functions

Common Risks of Improper Door Use

The control panel serves as the central hub for managing and customizing a computer's operating system, offering a suite of tools and settings that enable users to tailor their computing environment to their specific needs. Understanding common features and functions within the control panel is crucial for both casual users and professionals who wish to optimize their system's performance, security, and usability.


Cleaning and lubricating garage door components can prevent wear and tear garage door opener repair very near my area pixabay.com.

One of the quintessential functions found in most control panels is the ability to manage hardware devices connected to the computer. This includes printers, scanners, keyboards, mice, and external drives. Through these settings, users can update drivers, troubleshoot connectivity issues, or configure device-specific options such as print quality or mouse sensitivity. By ensuring that hardware components are correctly configured and up-to-date, users can maintain smooth interactions with their devices.


Another vital feature is network and internet settings management. This section allows users to connect to wireless networks, set up VPNs (Virtual Private Networks), or configure firewall settings. For instance, by adjusting firewall rules or enabling secure connections through a VPN, a user can enhance their online security significantly. Additionally, troubleshooting network problems often starts here; resetting network adapters or diagnosing connection issues are common tasks that can restore internet access swiftly.


The control panel also plays an indispensable role in personalizing user accounts and accessibility options. Users can create new accounts with varying levels of permission-ensuring privacy and security-or modify existing ones by changing passwords or account types. Accessibility options are particularly important for individuals with disabilities; features like screen readers, magnifiers, captioning services, or high-contrast themes ensure that technology remains inclusive and usable for everyone.


Security settings form another critical component of the control panel's offerings. Users have access to tools that protect against malicious software through built-in antivirus programs or regular system updates that patch vulnerabilities in the operating system. Such proactive measures are essential for safeguarding sensitive information from potential cyber threats.


Moreover, system maintenance tools within the control panel help keep computers running efficiently. Disk cleanup utilities remove unnecessary files cluttering storage space while defragmentation reorganizes data on hard drives for faster access times-a boon especially for older systems reliant on mechanical drives rather than solid-state ones.


In summary, reviewing common control panel functions reveals its pivotal role in everyday computing tasks-from configuring hardware devices and managing network connections to enhancing security protocols and optimizing overall system performance-all contributing toward creating an efficient digital experience tailored precisely around individual preferences while ensuring robust safety standards remain intact throughout usage periods without compromising operational effectiveness at any stage during continual active engagement with technological ecosystems prevalent today across diverse user demographics worldwide comprehensively without exception invariably always every time consistently indefinitely forevermore eternally perpetually unceasingly relentlessly continuously persistently perpetuating ceaselessly incessantly till eternity unending everlasting permanently enduring timelessly agelessly immortally imperishably indestructibly durably resiliently staunchly unwaveringly unfalteringly unswervingly resolutely steadfastly immovably adamantly determined stubborn obstinate tenacious dogged pertinacious unyielding inflexible inexorable relentless relentless relentless relentless!

In today's fast-paced digital age, the importance of safety and security features within control panels cannot be overstated. Whether they are used in industrial settings, home automation systems, or even basic software applications, ensuring that these control panels operate safely and securely is paramount. Understanding and reviewing the common functions of these panels can arm users with the knowledge needed to prevent accidents and safeguard sensitive information.


Firstly, one of the most vital safety features often found in control panels is emergency stop functionality. This feature allows operators to halt operations immediately during a malfunction or unexpected event. It is crucial for preventing accidents in environments where machinery operates at high speeds or temperatures. The placement and accessibility of this emergency stop button are also key factors; it should be easily reachable and clearly marked to ensure swift action when necessary.


Another critical aspect of safety in control panels is user authentication. Access controls are essential for maintaining security by ensuring only authorized personnel can operate or modify system settings. Passwords, biometric scans, or keycards can be implemented as part of this authentication process. By restricting access, organizations can significantly reduce the risk of unauthorized tampering which could lead to hazardous situations.


Furthermore, modern control panels often incorporate real-time monitoring systems. These systems provide continuous feedback on operational parameters such as temperature, pressure, or voltage levels. By receiving alerts on deviations from standard operating conditions early on, operators can take corrective actions before minor issues escalate into serious problems.


On the security front, encryption plays a pivotal role in safeguarding data transmitted through control panel interfaces. As many systems now connect over networks for remote monitoring and management capabilities, encrypting this data ensures that it remains confidential and protected from interception by malicious entities.


Additionally, audit trails are an invaluable security feature within control panels. By keeping detailed logs of all user activities and changes made within the system, audit trails help track actions back to individual users if irregularities occur. This level of accountability not only discourages potential misuse but also aids in forensic investigations should breaches occur.


Finally, regular maintenance checks and updates form an integral part of both safety and security protocols in control panel management. Keeping software up-to-date with the latest patches guards against vulnerabilities that cyber threats might exploit while ensuring hardware components remain functional reduces wear-and-tear failures that could compromise safety.


In conclusion, reviewing common control panel functions reveals a robust array of safety and security features designed to protect equipment integrity and human well-being alike. From emergency stops to encryption techniques-each element works cohesively to create resilient systems capable of withstanding both accidental mishaps and intentional intrusions alike. Understanding these functions not only empowers users but also fosters safer operational environments across various sectors worldwide.

Key differences between LiftMaster, Genie, and Chamberlain openers

When it comes to garage door openers, LiftMaster, Genie, and Chamberlain are among the most recognized brands in the market.. Each offers a range of models that vary in features, price, and value for money.

Key differences between LiftMaster, Genie, and Chamberlain openers

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The impact of motor power ratings on garage door performance

When considering the purchase or replacement of a garage door opener, one critical factor that often influences consumer decisions is the motor power rating.. The motor power rating significantly impacts the performance, efficiency, and longevity of a garage door system.

The impact of motor power ratings on garage door performance

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Common repair issues with Wi-Fi-enabled garage door openers

The convenience of Wi-Fi-enabled garage door openers has revolutionized modern home automation, offering homeowners the ability to control their garage doors from anywhere with an internet connection.. However, this technological advancement also brings to the forefront several remote access and security concerns that are essential to address in order to ensure both safety and functionality. One of the most prominent issues with Wi-Fi-enabled garage door openers is the potential for unauthorized access.

Common repair issues with Wi-Fi-enabled garage door openers

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Choosing the right opener for heavy or oversized garage doors

Choosing the right opener for heavy or oversized garage doors is an essential decision that can have significant cost implications.. When dealing with larger and heavier garage doors, the choice of an appropriate opener becomes crucial not only for functionality but also for budget management.

Choosing the right opener for heavy or oversized garage doors

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Importance of Professional Installation and Maintenance

In today's digital age, the ability to customize user preferences within control panels has become an essential function across various software and applications. Whether you're adjusting settings on your smartphone, configuring features on a new app, or personalizing your computer's desktop environment, customization options play a crucial role in enhancing user experience and satisfaction.


At its core, customization is about empowerment-giving users the ability to tailor their technological environment to best suit their individual needs and preferences. This personalization can range from simple aesthetic adjustments, such as changing themes or wallpapers, to more complex configurations like managing notifications or setting privacy controls. The overarching goal of these options is to make technology work for the user rather than forcing the user to adapt to rigid systems.


One of the most common areas for customization in control panels is display settings. Users frequently have the ability to adjust screen resolution, text size, and color schemes. These changes can significantly enhance readability and visual comfort, especially for individuals with specific visual requirements. Similarly, sound settings allow users to choose notification alerts that fit their preferences or even disable them entirely when silence is needed.


Another significant aspect of customization lies in accessibility options. Control panels often provide features designed to assist users with disabilities-such as screen readers for those with visual impairments or voice recognition software for those who may have difficulty using traditional input devices. By accommodating these diverse needs through customizable settings, technology becomes more inclusive and accessible.


Security settings are also paramount in control panel functions. Users can customize authentication methods-choosing between passwords, biometrics like fingerprint scanning or facial recognition-and set permissions for apps accessing sensitive information. This level of control not only enhances security but also builds trust between users and technology providers by putting privacy management into the hands of the user.


Moreover, customizing notifications allows users to stay informed without feeling overwhelmed by constant updates. Many control panels offer granular control over which alerts are received and how they are displayed-whether it's through banners that appear briefly on-screen or silent badges that accumulate until checked manually.


While these examples illustrate just some of the myriad ways customization enriches our interaction with technology, they collectively underscore a broader trend: the shift towards user-centric design principles. As consumers continue demanding greater agency over their digital experiences, developers are increasingly prioritizing flexible solutions that anticipate diverse needs and preferences.


In conclusion, reviewing common control panel functions reveals an evolving landscape where customization options serve as vital tools for optimizing user experiences across various platforms. By fostering environments tailored specifically around individual tastes and requirements-be it through adjusting visuals for comfort or fine-tuning notification frequencies-these customizable elements ensure a harmonious relationship between humans and technology that ultimately enhances productivity while promoting satisfaction along every step taken within this ever-evolving digital realm.

Importance of Professional Installation and Maintenance

Warning Signs of Malfunctioning Garage Doors

In the realm of modern technology, control panels serve as indispensable tools, orchestrating a myriad of functions with precision and efficiency. Whether it's the dashboard of a software application, the interface on a piece of machinery, or a central hub for home automation systems, control panels are designed to streamline operations and offer users an intuitive way to interact with complex systems. However, like any tool that integrates multiple functionalities, troubleshooting common issues with control panels is an inevitable aspect of their use.


At its core, a control panel is meant to simplify tasks by providing easy access to various features and settings. Yet, when these panels encounter issues, they can disrupt workflows and cause significant frustration. One prevalent problem users face is connectivity issues. Whether wired or wireless, reliable connections are crucial for control panels to function properly. Connectivity problems might stem from outdated software drivers or network disruptions. Regular updates and ensuring stable network conditions can mitigate such issues.


Another frequent challenge is user interface malfunctions. Control panels often rely on touch screens or buttons that can become unresponsive over time due to wear and tear or software glitches. In such cases, recalibrating the screen or performing a system reset may resolve the matter swiftly. It's also beneficial to keep the software updated as manufacturers regularly release patches that address known bugs.


Power supply problems represent another common issue encountered with control panels. An inconsistent power supply can lead to erratic performance or complete shutdowns. Ensuring that all cables are securely connected and checking for any visible damage can help identify hardware-related issues quickly.


Beyond these technical concerns lies the human element: understanding how to navigate the array of functions offered by control panels effectively. Many users experience difficulties simply because they are not fully acquainted with all available features or settings within their panel's interface. Reviewing user manuals and exploring tutorial resources can enhance one's familiarity with these systems.


Furthermore, security settings in control panels can sometimes pose challenges when misconfigured-leading to blocked access or limited functionality unintentionally imposed by overly strict permissions set by administrators unaware of their full impact.


Ultimately though troubleshooting might seem daunting at first glance; it offers opportunities for learning more about how our tools work beneath their sleek interfaces-a deeper appreciation developed through overcoming adversity faced while interacting daily via this technological bridge connecting us seamlessly into digital ecosystems surrounding everyday life activities both personal professional alike.


In conclusion tackling common issues associated involves both technical knowledge coupled alongside patient willingness delve deeper into intricacies involved therein-transformative process empowering individuals better equipped manage optimize experiences utilizing varied range devices applications dependent upon effective utilization comprehensive understanding capabilities limitations afforded them respective environments operating contexts whereupon deployed accordingly thus fostering greater confidence competence navigating ever-evolving technological landscapes ahead future endeavors await discovery exploration anew each passing day anew!

Safety Tips for Homeowners Using Garage Doors

In the age of digital innovation, the concept of a smart home is no longer confined to science fiction; it has become an integral part of modern living. Central to this transformation is the integration with smart home systems, which primarily rely on sophisticated control panels that serve as the nerve center for managing various functionalities. As we delve into reviewing common control panel functions, it becomes evident how these interfaces have revolutionized our interaction with household devices.


A smart home system's control panel acts as a unifying platform that seamlessly connects disparate devices such as lights, thermostats, security systems, and appliances. At its core, the control panel offers a user-friendly interface that allows homeowners to monitor and adjust these devices according to their preferences. One of the most common functions is energy management. Through intuitive controls and real-time data analytics displayed on the panel, users can optimize energy usage by adjusting lighting or setting heating and cooling schedules. This not only enhances convenience but also contributes significantly to reducing utility bills and environmental impact.


Security is another paramount function facilitated by these control panels. With integrated surveillance cameras and motion detectors connected through the system, homeowners can easily oversee their property from anywhere in the world via mobile apps linked to their control panels. Alerts for unusual activities or potential breaches are instantly relayed, providing peace of mind and allowing for prompt action if necessary.


The personalization aspect of smart home systems further exemplifies their versatility. Control panels often come equipped with customizable settings that cater to individual lifestyle needs. Users can create different scenarios or "scenes" such as 'movie night' or 'dinner party,' where multiple devices adjust simultaneously at the touch of a button to create the desired ambiance. This level of automation not only simplifies daily routines but also enriches home experiences.


Voice-enabled technology has taken integration a step further by incorporating virtual assistants like Amazon Alexa or Google Assistant into control panels. This hands-free operation allows users to execute commands effortlessly through voice prompts-whether it's dimming lights while reading in bed or playing music during a workout session in the living room.


Despite these advancements, challenges remain in ensuring seamless interoperability among devices from various manufacturers within a single ecosystem-a subject warranting continuous improvement for achieving universal compatibility standards across platforms.


In conclusion, reviewing common control panel functions reveals how integral they are in harnessing technology for creating smarter homes tailored towards enhancing comfort, efficiency, security-and ultimately transforming our way of life into one characterized by connectivity and intelligent automation.

When considering optimal performance in any system, whether it be a personal computer or a larger networked environment, understanding the control panel functions is paramount. The control panel acts as the nerve center for system management; it is where users can access settings that govern how software and hardware interact. By mastering these functions, you can ensure your devices run smoothly and efficiently.


One of the most critical aspects of maintaining optimal performance through the control panel is regular updates. Keeping your operating system, drivers, and software up to date is crucial for security and efficiency. Regular updates often include patches that fix bugs or vulnerabilities, which could otherwise slow down your system or lead to security breaches. Most control panels provide an automatic update feature; enabling this can save time and ensure that you are always running the latest versions.


Another essential function within the control panel is managing startup programs. Over time, many applications may set themselves to launch at startup without your knowledge. This can significantly slow down boot times and consume valuable resources right from the get-go. By accessing the startup settings through the control panel, you can disable unnecessary programs from launching at startup, thereby speeding up your computer's boot process and freeing up memory for more critical tasks.


System cleanup tools available in the control panel also play a vital role in maintaining optimal performance. These tools help remove temporary files, clear caches, and delete unnecessary data that accumulates over time. Regular use of disk cleanup utilities not only frees up space but also enhances system speed by organizing data more efficiently on your hard drive.


Security settings are another crucial area within the control panel that requires attention for maintaining optimal performance. Ensuring that firewall settings are correctly configured helps protect against unauthorized access while keeping antivirus software updated defends against malware threats. These precautions not only safeguard your data but also prevent potential slowdowns caused by malicious software.


Additionally, adjusting power management settings via the control panel can have a substantial impact on performance-especially for laptop users who need to balance performance with battery life. Choosing high-performance mode when plugged into power ensures maximum output from all components but switching to power-saving modes when relying on battery extends usage time without compromising essential functionalities.


In conclusion, regularly reviewing common control panel functions plays an integral role in achieving optimal performance for any electronic device. From updating software to managing startup programs and ensuring effective security measures-these actions collectively contribute towards a smoother user experience and prolonged device longevity. By dedicating some time to understand these controls better today, you pave way for efficient operations tomorrow-a small investment yielding significant returns in productivity and peace of mind alike.

Light-emitting diode
Blue, green, and red LEDs in 5 mm diffused cases. There are many different variants of LEDs.
Working principle Electroluminescence
Inventor
  • H. J. Round (1907)[1]
  • Oleg Losev (1927)[2]
  • James R. Biard (1961)[3]
  • Nick Holonyak (1962)[4]
First production  October 1962; 62 years ago (1962-10)
Pin names Anode and cathode
Electronic symbol
Parts of a conventional LED. The flat bottom surfaces of the anvil and post embedded inside the epoxy act as anchors, to prevent the conductors from being forcefully pulled out via mechanical strain or vibration.
Close-up image of a surface-mount LED
Close-up of an LED with the voltage being increased and decreased to show a detailed view of its operation
Modern LED retrofit with E27 screw in base
A bulb-shaped modern retrofit LED lamp with aluminum heat sink, a light diffusing dome and E27 screw base, using a built-in power supply working on mains voltage

A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor.[5] White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.[6]

Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light.[7] Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red.

Early LEDs were often used as indicator lamps, replacing small incandescent bulbs, and in seven-segment displays. Later developments produced LEDs available in visible, ultraviolet (UV), and infrared wavelengths with high, low, or intermediate light output, for instance, white LEDs suitable for room and outdoor lighting. LEDs have also given rise to new types of displays and sensors, while their high switching rates are useful in advanced communications technology with applications as diverse as aviation lighting, fairy lights, strip lights, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, lighted wallpaper, horticultural grow lights, and medical devices.[8]

LEDs have many advantages over incandescent light sources, including lower power consumption, a longer lifetime, improved physical robustness, smaller sizes, and faster switching. In exchange for these generally favorable attributes, disadvantages of LEDs include electrical limitations to low voltage and generally to DC (not AC) power, the inability to provide steady illumination from a pulsing DC or an AC electrical supply source, and a lesser maximum operating temperature and storage temperature.

LEDs are transducers of electricity into light. They operate in reverse of photodiodes, which convert light into electricity.

History

[edit]

The first LED was created by Soviet inventor Oleg Losev[9] in 1927, but electroluminescence was already known for 20 years, and relied on a diode made of silicon carbide.

Commercially viable LEDs only became available after Texas Instruments engineers patented efficient near-infrared emission from a diode based on GaAs in 1962.

From 1968, commercial LEDs were extremely costly and saw no practical use. Monsanto and Hewlett-Packard led the development of LEDs to the point where, in the 1970s, a unit cost less than five cents.[10]

Physics of light production and emission

[edit]

In a light-emitting diode, the recombination of electrons and electron holes in a semiconductor produces light (be it infrared, visible or UV), a process called "electroluminescence". The wavelength of the light depends on the energy band gap of the semiconductors used. Since these materials have a high index of refraction, design features of the devices such as special optical coatings and die shape are required to efficiently emit light.[11]

Unlike a laser, the light emitted from an LED is neither spectrally coherent nor even highly monochromatic. Its spectrum is sufficiently narrow that it appears to the human eye as a pure (saturated) color.[12][13] Also unlike most lasers, its radiation is not spatially coherent, so it cannot approach the very high intensity characteristic of lasers.

Single-color LEDs

[edit]
Blue LEDs
External videos
video icon "The Original Blue LED", Science History Institute

By selection of different semiconductor materials, single-color LEDs can be made that emit light in a narrow band of wavelengths from near-infrared through the visible spectrum and into the ultraviolet range. The required operating voltages of LEDs increase as the emitted wavelengths become shorter (higher energy, red to blue), because of their increasing semiconductor band gap.

Blue LEDs have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theory be varied from violet to amber.

Aluminium gallium nitride (AlGaN) of varying Al/Ga fraction can be used to manufacture the cladding and quantum well layers for ultraviolet LEDs, but these devices have not yet reached the level of efficiency and technological maturity of InGaN/GaN blue/green devices. If unalloyed GaN is used in this case to form the active quantum well layers, the device emits near-ultraviolet light with a peak wavelength centred around 365 nm. Green LEDs manufactured from the InGaN/GaN system are far more efficient and brighter than green LEDs produced with non-nitride material systems, but practical devices still exhibit efficiency too low for high-brightness applications.[citation needed]

With AlGaN and AlGaInN, even shorter wavelengths are achievable. Near-UV emitters at wavelengths around 360–395 nm are already cheap and often encountered, for example, as black light lamp replacements for inspection of anti-counterfeiting UV watermarks in documents and bank notes, and for UV curing. Substantially more expensive, shorter-wavelength diodes are commercially available for wavelengths down to 240 nm.[14] As the photosensitivity of microorganisms approximately matches the absorption spectrum of DNA, with a peak at about 260 nm, UV LED emitting at 250–270 nm are expected in prospective disinfection and sterilization devices. Recent research has shown that commercially available UVA LEDs (365 nm) are already effective disinfection and sterilization devices.[15] UV-C wavelengths were obtained in laboratories using aluminium nitride (210 nm),[16] boron nitride (215 nm)[17][18] and diamond (235 nm).[19]

White LEDs

[edit]

There are two primary ways of producing white light-emitting diodes. One is to use individual LEDs that emit three primary colors—red, green and blue—and then mix all the colors to form white light. The other is to use a phosphor material to convert monochromatic light from a blue or UV LED to broad-spectrum white light, similar to a fluorescent lamp. The yellow phosphor is cerium-doped YAG crystals suspended in the package or coated on the LED. This YAG phosphor causes white LEDs to appear yellow when off, and the space between the crystals allow some blue light to pass through in LEDs with partial phosphor conversion. Alternatively, white LEDs may use other phosphors like manganese(IV)-doped potassium fluorosilicate (PFS) or other engineered phosphors. PFS assists in red light generation, and is used in conjunction with conventional Ce:YAG phosphor.

In LEDs with PFS phosphor, some blue light passes through the phosphors, the Ce:YAG phosphor converts blue light to green and red (yellow) light, and the PFS phosphor converts blue light to red light. The color, emission spectrum or color temperature of white phosphor converted and other phosphor converted LEDs can be controlled by changing the concentration of several phosphors that form a phosphor blend used in an LED package.[20][21][22][23]

The 'whiteness' of the light produced is engineered to suit the human eye. Because of metamerism, it is possible to have quite different spectra that appear white. The appearance of objects illuminated by that light may vary as the spectrum varies. This is the issue of color rendition, quite separate from color temperature. An orange or cyan object could appear with the wrong color and much darker as the LED or phosphor does not emit the wavelength it reflects. The best color rendition LEDs use a mix of phosphors, resulting in less efficiency and better color rendering.[citation needed]

The first white light-emitting diodes (LEDs) were offered for sale in the autumn of 1996.[24] Nichia made some of the first white LEDs which were based on blue LEDs with Ce:YAG phosphor.[25] Ce:YAG is often grown using the Czochralski method.[26]

RGB systems

[edit]
Combined spectral curves for blue, yellow-green, and high-brightness red solid-state semiconductor LEDs. FWHM spectral bandwidth is approximately 24–27 nm for all three colors.
An RGB LED projecting red, green, and blue onto a surface

Mixing red, green, and blue sources to produce white light needs electronic circuits to control the blending of the colors. Since LEDs have slightly different emission patterns, the color balance may change depending on the angle of view, even if the RGB sources are in a single package, so RGB diodes are seldom used to produce white lighting. Nonetheless, this method has many applications because of the flexibility of mixing different colors,[27] and in principle, this mechanism also has higher quantum efficiency in producing white light.[28]

There are several types of multicolor white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency means lower color rendering, presenting a trade-off between the luminous efficacy and color rendering. For example, the dichromatic white LEDs have the best luminous efficacy (120 lm/W), but the lowest color rendering capability. Although tetrachromatic white LEDs have excellent color rendering capability, they often have poor luminous efficacy. Trichromatic white LEDs are in between, having both good luminous efficacy (>70 lm/W) and fair color rendering capability.[29]

One of the challenges is the development of more efficient green LEDs. The theoretical maximum for green LEDs is 683 lumens per watt but as of 2010 few green LEDs exceed even 100 lumens per watt. The blue and red LEDs approach their theoretical limits.[citation needed]

Multicolor LEDs offer a means to form light of different colors. Most perceivable colors can be formed by mixing different amounts of three primary colors. This allows precise dynamic color control. Their emission power decays exponentially with rising temperature,[30] resulting in a substantial change in color stability. Such problems inhibit industrial use. Multicolor LEDs without phosphors cannot provide good color rendering because each LED is a narrowband source. LEDs without phosphor, while a poorer solution for general lighting, are the best solution for displays, either backlight of LCD, or direct LED based pixels.

Dimming a multicolor LED source to match the characteristics of incandescent lamps is difficult because manufacturing variations, age, and temperature change the actual color value output. To emulate the appearance of dimming incandescent lamps may require a feedback system with color sensor to actively monitor and control the color.[31]

Phosphor-based LEDs

[edit]
Spectrum of a white LED showing blue light directly emitted by the GaN-based LED (peak at about 465 nm) and the more broadband Stokes-shifted light emitted by the Ce3+:YAG phosphor, which emits at roughly 500–700 nm

This method involves coating LEDs of one color (mostly blue LEDs made of InGaN) with phosphors of different colors to form white light; the resultant LEDs are called phosphor-based or phosphor-converted white LEDs (pcLEDs).[32] A fraction of the blue light undergoes the Stokes shift, which transforms it from shorter wavelengths to longer. Depending on the original LED's color, various color phosphors are used. Using several phosphor layers of distinct colors broadens the emitted spectrum, effectively raising the color rendering index (CRI).[33]

Phosphor-based LEDs have efficiency losses due to heat loss from the Stokes shift and also other phosphor-related issues. Their luminous efficacies compared to normal LEDs depend on the spectral distribution of the resultant light output and the original wavelength of the LED itself. For example, the luminous efficacy of a typical YAG yellow phosphor based white LED ranges from 3 to 5 times the luminous efficacy of the original blue LED because of the human eye's greater sensitivity to yellow than to blue (as modeled in the luminosity function).

Due to the simplicity of manufacturing, the phosphor method is still the most popular method for making high-intensity white LEDs. The design and production of a light source or light fixture using a monochrome emitter with phosphor conversion is simpler and cheaper than a complex RGB system, and the majority of high-intensity white LEDs presently on the market are manufactured using phosphor light conversion.[citation needed]

1 watt 9 volt three chips SMD phosphor based white LED

Among the challenges being faced to improve the efficiency of LED-based white light sources is the development of more efficient phosphors. As of 2010, the most efficient yellow phosphor is still the YAG phosphor, with less than 10% Stokes shift loss. Losses attributable to internal optical losses due to re-absorption in the LED chip and in the LED packaging itself account typically for another 10% to 30% of efficiency loss. Currently, in the area of phosphor LED development, much effort is being spent on optimizing these devices to higher light output and higher operation temperatures. For instance, the efficiency can be raised by adapting better package design or by using a more suitable type of phosphor. Conformal coating process is frequently used to address the issue of varying phosphor thickness.[citation needed]

Some phosphor-based white LEDs encapsulate InGaN blue LEDs inside phosphor-coated epoxy. Alternatively, the LED might be paired with a remote phosphor, a preformed polycarbonate piece coated with the phosphor material. Remote phosphors provide more diffuse light, which is desirable for many applications. Remote phosphor designs are also more tolerant of variations in the LED emissions spectrum. A common yellow phosphor material is cerium-doped yttrium aluminium garnet (Ce3+:YAG).[citation needed]

White LEDs can also be made by coating near-ultraviolet (NUV) LEDs with a mixture of high-efficiency europium-based phosphors that emit red and blue, plus copper and aluminium-doped zinc sulfide (ZnS:Cu, Al) that emits green. This is a method analogous to the way fluorescent lamps work. This method is less efficient than blue LEDs with YAG:Ce phosphor, as the Stokes shift is larger, so more energy is converted to heat, but yields light with better spectral characteristics, which render color better. Due to the higher radiative output of the ultraviolet LEDs than of the blue ones, both methods offer comparable brightness. A concern is that UV light may leak from a malfunctioning light source and cause harm to human eyes or skin.[citation needed]

A new style of wafers composed of gallium-nitride-on-silicon (GaN-on-Si) is being used to produce white LEDs using 200-mm silicon wafers. This avoids the typical costly sapphire substrate in relatively small 100- or 150-mm wafer sizes.[34] The sapphire apparatus must be coupled with a mirror-like collector to reflect light that would otherwise be wasted. It was predicted that since 2020, 40% of all GaN LEDs are made with GaN-on-Si. Manufacturing large sapphire material is difficult, while large silicon material is cheaper and more abundant. LED companies shifting from using sapphire to silicon should be a minimal investment.[35]

Mixed white LEDs

[edit]
Tunable white LED array in a floodlight

There are RGBW LEDs that combine RGB units with a phosphor white LED on the market. Doing so retains the extremely tunable color of RGB LED, but allows color rendering and efficiency to be optimized when a color close to white is selected.[36]

Some phosphor white LED units are "tunable white", blending two extremes of color temperatures (commonly 2700K and 6500K) to produce intermediate values. This feature allows users to change the lighting to suit the current use of a multifunction room.[37] As illustrated by a straight line on the chromaticity diagram, simple two-white blends will have a pink bias, becoming most severe in the middle. A small amount of green light, provided by another LED, could correct the problem.[38] Some products are RGBWW, i.e. RGBW with tunable white.[39]

A final class of white LED with mixed light is dim-to-warm. These are ordinary 2700K white LED bulbs with a small red LED that turns on when the bulb is dimmed. Doing so makes the color warmer, emulating an incandescent light bulb.[39]

Other white LEDs

[edit]

Another method used to produce experimental white light LEDs used no phosphors at all and was based on homoepitaxially grown zinc selenide (ZnSe) on a ZnSe substrate that simultaneously emitted blue light from its active region and yellow light from the substrate.[40]

Organic light-emitting diodes (OLEDs)

[edit]

In an organic light-emitting diode (OLED), the electroluminescent material composing the emissive layer of the diode is an organic compound. The organic material is electrically conductive due to the delocalization of pi electrons caused by conjugation over all or part of the molecule, and the material therefore functions as an organic semiconductor.[41] The organic materials can be small organic molecules in a crystalline phase, or polymers.[42]

The potential advantages of OLEDs include thin, low-cost displays with a low driving voltage, wide viewing angle, and high contrast and color gamut.[43] Polymer LEDs have the added benefit of printable and flexible displays.[44][45][46] OLEDs have been used to make visual displays for portable electronic devices such as cellphones, digital cameras, lighting and televisions.[42][43]

Types

[edit]
LEDs are produced in a variety of shapes and sizes. The color of the plastic lens is often the same as the actual color of light emitted, but not always. For instance, purple plastic is often used for infrared LEDs, and most blue devices have colorless housings. Modern high-power LEDs such as those used for lighting and backlighting are generally found in surface-mount technology (SMT) packages (not shown).
A variety of different diffused 5 mm THT-LEDs
  • Red, 650 – 625nm
  • Orange, 600 – 610nm
  • Yellow, 587 – 591nm
  • Green, 570 – 575nm
  • Blue, 465 – 467nm
  • Purple, 395 – 400nm

LEDs are made in different packages for different applications. A single or a few LED junctions may be packed in one miniature device for use as an indicator or pilot lamp. An LED array may include controlling circuits within the same package, which may range from a simple resistor, blinking or color changing control, or an addressable controller for RGB devices. Higher-powered white-emitting devices will be mounted on heat sinks and will be used for illumination. Alphanumeric displays in dot matrix or bar formats are widely available. Special packages permit connection of LEDs to optical fibers for high-speed data communication links.

Miniature

[edit]
Image of miniature surface mount LEDs in most common sizes. They can be much smaller than a traditional 5 mm lamp type LED, shown on the upper left corner.
Very small (1.6×1.6×0.35 mm) red, green, and blue surface mount miniature LED package with gold wire bonding details

These are mostly single-die LEDs used as indicators, and they come in various sizes from 1.8 mm to 10 mm, through-hole and surface mount packages.[47] Typical current ratings range from around 1 mA to above 20 mA. LED's can be soldered to a flexible PCB strip to form LED tape popularly used for decoration.

Common package shapes include round, with a domed or flat top, rectangular with a flat top (as used in bar-graph displays), and triangular or square with a flat top. The encapsulation may also be clear or tinted to improve contrast and viewing angle. Infrared devices may have a black tint to block visible light while passing infrared radiation, such as the Osram SFH 4546.[48]

5 V and 12 V LEDs are ordinary miniature LEDs that have a series resistor for direct connection to a 5 V or 12 V supply.[49]

High-power

[edit]
High-power light-emitting diodes attached to an LED star base (Luxeon, Lumileds)

High-power LEDs (HP-LEDs) or high-output LEDs (HO-LEDs) can be driven at currents from hundreds of mA to more than an ampere, compared with the tens of mA for other LEDs. Some can emit over a thousand lumens.[50][51] LED power densities up to 300 W/cm2 have been achieved. Since overheating is destructive, the HP-LEDs must be mounted on a heat sink to allow for heat dissipation. If the heat from an HP-LED is not removed, the device fails in seconds. One HP-LED can often replace an incandescent bulb in a flashlight, or be set in an array to form a powerful LED lamp.

Some HP-LEDs in this category are the Nichia 19 series, Lumileds Rebel Led, Osram Opto Semiconductors Golden Dragon, and Cree X-lamp. As of September 2009, some HP-LEDs manufactured by Cree exceed 105 lm/W.[52]

Examples for Haitz's law—which predicts an exponential rise in light output and efficacy of LEDs over time—are the CREE XP-G series LED, which achieved 105 lm/W in 2009[52] and the Nichia 19 series with a typical efficacy of 140 lm/W, released in 2010.[53]

AC-driven

[edit]

LEDs developed by Seoul Semiconductor can operate on AC power without a DC converter. For each half-cycle, part of the LED emits light and part is dark, and this is reversed during the next half-cycle. The efficiency of this type of HP-LED is typically 40 lm/W.[54] A large number of LED elements in series may be able to operate directly from line voltage. In 2009, Seoul Semiconductor released a high DC voltage LED, named 'Acrich MJT', capable of being driven from AC power with a simple controlling circuit. The low-power dissipation of these LEDs affords them more flexibility than the original AC LED design.[55]

Strip

[edit]
Several LED spots being reflected as continuous lighting strip

An LED strip, tape, or ribbon light is a flexible circuit board populated by surface-mount light-emitting diodes (SMD LEDs) and other components that usually comes with an adhesive backing. Traditionally, strip lights had been used solely in accent lighting, backlighting, task lighting, and decorative lighting applications, such as cove lighting.

LED strip lights originated in the early 2000s. Since then, increased luminous efficacy and higher-power SMDs have allowed them to be used in applications such as high brightness task lighting, fluorescent and halogen lighting fixture replacements, indirect lighting applications, ultraviolet inspection during manufacturing processes, set and costume design, and growing plants.

Application-specific

[edit]
RGB-SMD-LED
Composite image of an 11 × 44 LED matrix lapel name tag display using 1608/0603-type SMD LEDs. Top: A little over half of the 21 × 86 mm display. Center: Close-up of LEDs in ambient light. Bottom: LEDs in their own red light.
Flashing
Flashing LEDs are used as attention seeking indicators without requiring external electronics. Flashing LEDs resemble standard LEDs but they contain an integrated voltage regulator and a multivibrator circuit that causes the LED to flash with a typical period of one second. In diffused lens LEDs, this circuit is visible as a small black dot. Most flashing LEDs emit light of one color, but more sophisticated devices can flash between multiple colors and even fade through a color sequence using RGB color mixing. Flashing SMD LEDs in the 0805 and other size formats have been available since early 2019.
Flickering
Integrated electronics Simple electronic circuits integrated into the LED package have been around since at least 2011 which produce a random LED intensity pattern reminiscent of a flickering candle.[56] Reverse engineering in 2024 has suggested that some flickering LEDs with automatic sleep and wake modes might be using an integrated 8-bit microcontroller for such functionally.[57]
Bi-color
Bi-color LEDs contain two different LED emitters in one case. There are two types of these. One type consists of two dies connected to the same two leads antiparallel to each other. Current flow in one direction emits one color, and current in the opposite direction emits the other color. The other type consists of two dies with separate leads for both dies and another lead for common anode or cathode so that they can be controlled independently. The most common bi-color combination is red/traditional green. Others include amber/traditional green, red/pure green, red/blue, and blue/pure green.
RGB tri-color
Tri-color LEDs contain three different LED emitters in one case. Each emitter is connected to a separate lead so they can be controlled independently. A four-lead arrangement is typical with one common lead (anode or cathode) and an additional lead for each color. Others have only two leads (positive and negative) and have a built-in electronic controller. RGB LEDs consist of one red, one green, and one blue LED.[58] By independently adjusting each of the three, RGB LEDs are capable of producing a wide color gamut. Unlike dedicated-color LEDs, these do not produce pure wavelengths. Modules may not be optimized for smooth color mixing.
Decorative-multicolor
Decorative-multicolor LEDs incorporate several emitters of different colors supplied by only two lead-out wires. Colors are switched internally by varying the supply voltage.
Alphanumeric
Alphanumeric LEDs are available in seven-segment, starburst, and dot-matrix format. Seven-segment displays handle all numbers and a limited set of letters. Starburst displays can display all letters. Dot-matrix displays typically use 5×7 pixels per character. Seven-segment LED displays were in widespread use in the 1970s and 1980s, but rising use of liquid crystal displays, with their lower power needs and greater display flexibility, has reduced the popularity of numeric and alphanumeric LED displays.
Digital RGB
Digital RGB addressable LEDs contain their own "smart" control electronics. In addition to power and ground, these provide connections for data-in, data-out, clock and sometimes a strobe signal. These are connected in a daisy chain, which allows individual LEDs in a long LED strip light to be easily controlled by a microcontroller. Data sent to the first LED of the chain can control the brightness and color of each LED independently of the others. They are used where a combination of maximum control and minimum visible electronics are needed such as strings for Christmas and LED matrices. Some even have refresh rates in the kHz range, allowing for basic video applications. These devices are known by their part number (WS2812 being common) or a brand name such as NeoPixel.
Filament
An LED filament consists of multiple LED chips connected in series on a common longitudinal substrate that forms a thin rod reminiscent of a traditional incandescent filament.[59] These are being used as a low-cost decorative alternative for traditional light bulbs that are being phased out in many countries. The filaments use a rather high voltage, allowing them to work efficiently with mains voltages. Often a simple rectifier and capacitive current limiting are employed to create a low-cost replacement for a traditional light bulb without the complexity of the low voltage, high current converter that single die LEDs need.[60] Usually, they are packaged in bulb similar to the lamps they were designed to replace, and filled with inert gas at slightly lower than ambient pressure to remove heat efficiently and prevent corrosion.
Chip-on-board arrays
Surface-mounted LEDs are frequently produced in chip on board (COB) arrays, allowing better heat dissipation than with a single LED of comparable luminous output.[61] The LEDs can be arranged around a cylinder, and are called "corn cob lights" because of the rows of yellow LEDs.[62]

Considerations for use

[edit]
  • Efficiency: LEDs emit more lumens per watt than incandescent light bulbs.[63] The efficiency of LED lighting fixtures is not affected by shape and size, unlike fluorescent light bulbs or tubes.
  • Size: LEDs can be very small (smaller than 2 mm2[64]) and are easily attached to printed circuit boards.

Power sources

[edit]
Simple LED circuit with resistor for current limiting

The current in an LED or other diodes rises exponentially with the applied voltage (see Shockley diode equation), so a small change in voltage can cause a large change in current. Current through the LED must be regulated by an external circuit such as a constant current source to prevent damage. Since most common power supplies are (nearly) constant-voltage sources, LED fixtures must include a power converter, or at least a current-limiting resistor. In some applications, the internal resistance of small batteries is sufficient to keep current within the LED rating.[citation needed]

LEDs are sensitive to voltage. They must be supplied with a voltage above their threshold voltage and a current below their rating. Current and lifetime change greatly with a small change in applied voltage. They thus require a current-regulated supply (usually just a series resistor for indicator LEDs).[65]

Efficiency droop: The efficiency of LEDs decreases as the electric current increases. Heating also increases with higher currents, which compromises LED lifetime. These effects put practical limits on the current through an LED in high power applications.[66]

Electrical polarity

[edit]

Unlike a traditional incandescent lamp, an LED will light only when voltage is applied in the forward direction of the diode. No current flows and no light is emitted if voltage is applied in the reverse direction. If the reverse voltage exceeds the breakdown voltage, which is typically about five volts, a large current flows and the LED will be damaged. If the reverse current is sufficiently limited to avoid damage, the reverse-conducting LED is a useful noise diode.[citation needed]

By definition, the energy band gap of any diode is higher when reverse-biased than when forward-biased. Because the band gap energy determines the wavelength of the light emitted, the color cannot be the same when reverse-biased. The reverse breakdown voltage is sufficiently high that the emitted wavelength cannot be similar enough to still be visible. Though dual-LED packages exist that contain a different color LED in each direction, it is not expected that any single LED element can emit visible light when reverse-biased.[citation needed]

It is not known if any zener diode could exist that emits light only in reverse-bias mode. Uniquely, this type of LED would conduct when connected backwards.

Appearance

[edit]
  • Color: LEDs can emit light of an intended color without using any color filters as traditional lighting methods need. This is more efficient and can lower initial costs.
  • Cool light: In contrast to most light sources, LEDs radiate very little heat in the form of IR that can cause damage to sensitive objects or fabrics. Wasted energy is dispersed as heat through the base of the LED.
  • Color rendition: Most cool-white LEDs have spectra that differ significantly from a black body radiator like the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can make the color of objects appear differently under cool-white LED illumination than sunlight or incandescent sources, due to metamerism,[67] red surfaces being rendered particularly poorly by typical phosphor-based cool-white LEDs. The same is true with green surfaces. The quality of color rendition of an LED is measured by the Color Rendering Index (CRI).
  • Dimming: LEDs can be dimmed either by pulse-width modulation or lowering the forward current.[68] This pulse-width modulation is why LED lights, particularly headlights on cars, when viewed on camera or by some people, seem to flash or flicker. This is a type of stroboscopic effect.

Light properties

[edit]
  • Switch on time: LEDs light up extremely quickly. A typical red indicator LED achieves full brightness in under a microsecond.[69] LEDs used in communications devices can have even faster response times.
  • Focus: The solid package of the LED can be designed to focus its light. Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner. For larger LED packages total internal reflection (TIR) lenses are often used to the same effect. When large quantities of light are needed, many light sources such as LED chips are usually deployed, which are difficult to focus or collimate on the same target.
  • Area light source: Single LEDs do not approximate a point source of light giving a spherical light distribution, but rather a lambertian distribution. So, LEDs are difficult to apply to uses needing a spherical light field. Different fields of light can be manipulated by the application of different optics or "lenses". LEDs cannot provide divergence below a few degrees.[70]

Reliability

[edit]
  • Shock resistance: LEDs, being solid-state components, are difficult to damage with external shock, unlike fluorescent and incandescent bulbs, which are fragile.[71]
  • Thermal runaway: Parallel strings of LEDs will not share current evenly due to the manufacturing tolerances in their forward voltage. Running two or more strings from a single current source may result in LED failure as the devices warm up. If forward voltage binning is not possible, a circuit is required to ensure even distribution of current between parallel strands.[72]
  • Slow failure: LEDs mainly fail by dimming over time, rather than the abrupt failure of incandescent bulbs.[73]
  • Lifetime: LEDs can have a relatively long useful life. One report estimates 35,000 to 50,000 hours of useful life, though time to complete failure may be shorter or longer.[74] Fluorescent tubes typically are rated at about 10,000 to 25,000 hours, depending partly on the conditions of use, and incandescent light bulbs at 1,000 to 2,000 hours. Several DOE demonstrations have shown that reduced maintenance costs from this extended lifetime, rather than energy savings, is the primary factor in determining the payback period for an LED product.[75]
  • Cycling: LEDs are ideal for uses subject to frequent on-off cycling, unlike incandescent and fluorescent lamps that fail faster when cycled often, or high-intensity discharge lamps (HID lamps) that require a long time to warm up to full output and to cool down before they can be lighted again if they are being restarted.
  • Temperature dependence: LED performance largely depends on the ambient temperature of the operating environment – or thermal management properties. Overdriving an LED in high ambient temperatures may result in overheating the LED package, eventually leading to device failure. An adequate heat sink is needed to maintain long life. This is especially important in automotive, medical, and military uses where devices must operate over a wide range of temperatures, and require low failure rates.

Manufacturing

[edit]

LED manufacturing involves multiple steps, including epitaxy, chip processing, chip separation, and packaging.[76]

In a typical LED manufacturing process, encapsulation is performed after probing, dicing, die transfer from wafer to package, and wire bonding or flip chip mounting,[77] perhaps using indium tin oxide, a transparent electrical conductor. In this case, the bond wire(s) are attached to the ITO film that has been deposited in the LEDs.

Flip chip circuit on board (COB) is a technique that can be used to manufacture LEDs.[78]

Colors and materials

[edit]

Conventional LEDs are made from a variety of inorganic semiconductor materials. The following table shows the available colors with wavelength range, voltage drop and material:

  Color Wavelength (nm) Voltage (V) Semiconductor material
  Infrared λ > 760 ΔV < 1.9 Gallium arsenide (GaAs)

Aluminium gallium arsenide (AlGaAs)

  Red 610 < λ < 760 1.63 < ΔV < 2.03 Aluminium gallium arsenide (AlGaAs)

Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)

  Orange 590 < λ < 610 2.03 < ΔV < 2.10 Gallium arsenide phosphide (GaAsP)

Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)

  Yellow 570 < λ < 590 2.10 < ΔV < 2.18 Gallium arsenide phosphide (GaAsP)

Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP)

  Green 500 < λ < 570 1.9[79] < ΔV < 4.0 Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN)

Gallium(III) phosphide (GaP) Aluminium gallium indium phosphide (AlGaInP) Aluminium gallium phosphide (AlGaP)

  Blue 450 < λ < 500 2.48 < ΔV < 3.7 Zinc selenide (ZnSe)

Indium gallium nitride (InGaN) Silicon carbide (SiC) as substrate Silicon (Si) as substrate — (under development)

  Violet 400 < λ < 450 2.76 < ΔV < 4.0 Indium gallium nitride (InGaN)
  Purple multiple types 2.48 < ΔV < 3.7 Dual blue/red LEDs,

blue with red phosphor, or white with purple plastic

  Ultraviolet λ < 400 3.1 < ΔV < 4.4 Diamond (235 nm)[80]

Boron nitride (215 nm)[81][82] Aluminium nitride (AlN) (210 nm)[16]

Aluminium gallium nitride (AlGaN) Aluminium gallium indium nitride (AlGaInN) — (down to 210 nm)[83]

  White Broad spectrum 2.7 < ΔV < 3.5 Blue diode with yellow phosphor or violet/UV diode with multi-color phosphor  

Applications

[edit]
Daytime running light LEDs of an automobile

LED uses fall into five major categories:

  • Visual signals where light goes more or less directly from the source to the human eye, to convey a message or meaning
  • Illumination where light is reflected from objects to give visual response of these objects
  • Measuring and interacting with processes involving no human vision[84]
  • Narrow band light sensors where LEDs operate in a reverse-bias mode and respond to incident light, instead of emitting light[85][86][87][88]
  • Indoor cultivation, including cannabis.[89]

The application of LEDs in horticulture has revolutionized plant cultivation by providing energy-efficient, customizable lighting solutions that optimize plant growth and development.[90] LEDs offer precise control over light spectra, intensity, and photoperiods, enabling growers to tailor lighting conditions to the specific needs of different plant species and growth stages. This technology enhances photosynthesis, improves crop yields, and reduces energy costs compared to traditional lighting systems. Additionally, LEDs generate less heat, allowing closer placement to plants without risking thermal damage, and contribute to sustainable farming practices by lowering carbon footprints and extending growing seasons in controlled environments.[91] Light spectrum affects growth, metabolite profile, and resistance against fungal phytopathogens of Solanum lycopersicum seedlings.[92] LEDs can also be used in micropropagation.[93]

Indicators and signs

[edit]

The low energy consumption, low maintenance and small size of LEDs has led to uses as status indicators and displays on a variety of equipment and installations. Large-area LED displays are used as stadium displays, dynamic decorative displays, and dynamic message signs on freeways. Thin, lightweight message displays are used at airports and railway stations, and as destination displays for trains, buses, trams, and ferries.

Red and green LED traffic signals

One-color light is well suited for traffic lights and signals, exit signs, emergency vehicle lighting, ships' navigation lights, and LED-based Christmas lights

Because of their long life, fast switching times, and visibility in broad daylight due to their high output and focus, LEDs have been used in automotive brake lights and turn signals. The use in brakes improves safety, due to a great reduction in the time needed to light fully, or faster rise time, about 0.1 second faster[citation needed] than an incandescent bulb. This gives drivers behind more time to react. In a dual intensity circuit (rear markers and brakes) if the LEDs are not pulsed at a fast enough frequency, they can create a phantom array, where ghost images of the LED appear if the eyes quickly scan across the array. White LED headlamps are beginning to appear. Using LEDs has styling advantages because LEDs can form much thinner lights than incandescent lamps with parabolic reflectors.

Due to the relative cheapness of low output LEDs, they are also used in many temporary uses such as glowsticks and throwies. Artists have also used LEDs for LED art.

Lighting

[edit]

With the development of high-efficiency and high-power LEDs, it has become possible to use LEDs in lighting and illumination. To encourage the shift to LED lamps and other high-efficiency lighting, in 2008 the US Department of Energy created the L Prize competition. The Philips Lighting North America LED bulb won the first competition on August 3, 2011, after successfully completing 18 months of intensive field, lab, and product testing.[94]

Efficient lighting is needed for sustainable architecture. As of 2011, some LED bulbs provide up to 150 lm/W and even inexpensive low-end models typically exceed 50 lm/W, so that a 6-watt LED could achieve the same results as a standard 40-watt incandescent bulb. The lower heat output of LEDs also reduces demand on air conditioning systems. Worldwide, LEDs are rapidly adopted to displace less effective sources such as incandescent lamps and CFLs and reduce electrical energy consumption and its associated emissions. Solar powered LEDs are used as street lights and in architectural lighting.

The mechanical robustness and long lifetime are used in automotive lighting on cars, motorcycles, and bicycle lights. LED street lights are employed on poles and in parking garages. In 2007, the Italian village of Torraca was the first place to convert its street lighting to LEDs.[95]

Cabin lighting on recent[when?] Airbus and Boeing jetliners uses LED lighting. LEDs are also being used in airport and heliport lighting. LED airport fixtures currently include medium-intensity runway lights, runway centerline lights, taxiway centerline and edge lights, guidance signs, and obstruction lighting.

LEDs are also used as a light source for DLP projectors, and to backlight newer LCD television (referred to as LED TV), computer monitor (including laptop) and handheld device LCDs, succeeding older CCFL-backlit LCDs although being superseded by OLED screens. RGB LEDs raise the color gamut by as much as 45%. Screens for TV and computer displays can be made thinner using LEDs for backlighting.[96]

LEDs are small, durable and need little power, so they are used in handheld devices such as flashlights. LED strobe lights or camera flashes operate at a safe, low voltage, instead of the 250+ volts commonly found in xenon flashlamp-based lighting. This is especially useful in cameras on mobile phones, where space is at a premium and bulky voltage-raising circuitry is undesirable.

LEDs are used for infrared illumination in night vision uses including security cameras. A ring of LEDs around a video camera, aimed forward into a retroreflective background, allows chroma keying in video productions.

LED for miners, to increase visibility inside mines
Los Angeles Vincent Thomas Bridge illuminated with blue LEDs

LEDs are used in mining operations, as cap lamps to provide light for miners. Research has been done to improve LEDs for mining, to reduce glare and to increase illumination, reducing risk of injury to the miners.[97]

LEDs are increasingly finding uses in medical and educational applications, for example as mood enhancement.[98] NASA has even sponsored research for the use of LEDs to promote health for astronauts.[99]

Data communication and other signalling

[edit]

Light can be used to transmit data and analog signals. For example, lighting white LEDs can be used in systems assisting people to navigate in closed spaces while searching necessary rooms or objects.[100]

Assistive listening devices in many theaters and similar spaces use arrays of infrared LEDs to send sound to listeners' receivers. Light-emitting diodes (as well as semiconductor lasers) are used to send data over many types of fiber optic cable, from digital audio over TOSLINK cables to the very high bandwidth fiber links that form the Internet backbone. For some time, computers were commonly equipped with IrDA interfaces, which allowed them to send and receive data to nearby machines via infrared.

Because LEDs can cycle on and off millions of times per second, very high data bandwidth can be achieved.[101] For that reason, visible light communication (VLC) has been proposed as an alternative to the increasingly competitive radio bandwidth.[102] VLC operates in the visible part of the electromagnetic spectrum, so data can be transmitted without occupying the frequencies of radio communications.

Machine vision systems

[edit]

Machine vision systems often require bright and homogeneous illumination, so features of interest are easier to process. LEDs are often used.

Barcode scanners are the most common example of machine vision applications, and many of those scanners use red LEDs instead of lasers. Optical computer mice use LEDs as a light source for the miniature camera within the mouse.

LEDs are useful for machine vision because they provide a compact, reliable source of light. LED lamps can be turned on and off to suit the needs of the vision system, and the shape of the beam produced can be tailored to match the system's requirements.

Biological detection

[edit]

The discovery of radiative recombination in aluminum gallium nitride (AlGaN) alloys by U.S. Army Research Laboratory (ARL) led to the conceptualization of UV light-emitting diodes (LEDs) to be incorporated in light-induced fluorescence sensors used for biological agent detection.[103][104][105] In 2004, the Edgewood Chemical Biological Center (ECBC) initiated the effort to create a biological detector named TAC-BIO. The program capitalized on semiconductor UV optical sources (SUVOS) developed by the Defense Advanced Research Projects Agency (DARPA).[105]

UV-induced fluorescence is one of the most robust techniques used for rapid real-time detection of biological aerosols.[105] The first UV sensors were lasers lacking in-field-use practicality. In order to address this, DARPA incorporated SUVOS technology to create a low-cost, small, lightweight, low-power device. The TAC-BIO detector's response time was one minute from when it sensed a biological agent. It was also demonstrated that the detector could be operated unattended indoors and outdoors for weeks at a time.[105]

Aerosolized biological particles fluoresce and scatter light under a UV light beam. Observed fluorescence is dependent on the applied wavelength and the biochemical fluorophores within the biological agent. UV induced fluorescence offers a rapid, accurate, efficient and logistically practical way for biological agent detection. This is because the use of UV fluorescence is reagentless, or a process that does not require an added chemical to produce a reaction, with no consumables, or produces no chemical byproducts.[105]

Additionally, TAC-BIO can reliably discriminate between threat and non-threat aerosols. It was claimed to be sensitive enough to detect low concentrations, but not so sensitive that it would cause false positives. The particle-counting algorithm used in the device converted raw data into information by counting the photon pulses per unit of time from the fluorescence and scattering detectors, and comparing the value to a set threshold.[106]

The original TAC-BIO was introduced in 2010, while the second-generation TAC-BIO GEN II, was designed in 2015 to be more cost-efficient, as plastic parts were used. Its small, light-weight design allows it to be mounted to vehicles, robots, and unmanned aerial vehicles. The second-generation device could also be utilized as an environmental detector to monitor air quality in hospitals, airplanes, or even in households to detect fungus and mold.[107][108]

Other applications

[edit]
LED costume for stage performers
LED wallpaper by Meystyle
A large LED display behind a disc jockey
Seven-segment display that can display four digits and points
LED panel light source used in an early experiment on potato growth during Shuttle mission STS-73 to investigate the potential for growing food on future long duration missions

The light from LEDs can be modulated very quickly so they are used extensively in optical fiber and free space optics communications. This includes remote controls, such as for television sets, where infrared LEDs are often used. Opto-isolators use an LED combined with a photodiode or phototransistor to provide a signal path with electrical isolation between two circuits. This is especially useful in medical equipment where the signals from a low-voltage sensor circuit (usually battery-powered) in contact with a living organism must be electrically isolated from any possible electrical failure in a recording or monitoring device operating at potentially dangerous voltages. An optoisolator also lets information be transferred between circuits that do not share a common ground potential.

Many sensor systems rely on light as the signal source. LEDs are often ideal as a light source due to the requirements of the sensors. The Nintendo Wii's sensor bar uses infrared LEDs. Pulse oximeters use them for measuring oxygen saturation. Some flatbed scanners use arrays of RGB LEDs rather than the typical cold-cathode fluorescent lamp as the light source. Having independent control of three illuminated colors allows the scanner to calibrate itself for more accurate color balance, and there is no need for warm-up. Further, its sensors only need be monochromatic, since at any one time the page being scanned is only lit by one color of light.

Since LEDs can also be used as photodiodes, they can be used for both photo emission and detection. This could be used, for example, in a touchscreen that registers reflected light from a finger or stylus.[109] Many materials and biological systems are sensitive to, or dependent on, light. Grow lights use LEDs to increase photosynthesis in plants,[110] and bacteria and viruses can be removed from water and other substances using UV LEDs for sterilization.[15] LEDs of certain wavelengths have also been used for light therapy treatment of neonatal jaundice and acne.[111]

UV LEDs, with spectra range of 220 nm to 395 nm, have other applications, such as water/air purification, surface disinfection, glue curing, free-space non-line-of-sight communication, high performance liquid chromatography, UV curing dye printing, phototherapy (295nm Vitamin D, 308nm Excimer lamp or laser replacement), medical/ analytical instrumentation, and DNA absorption.[104][112]

LEDs have also been used as a medium-quality voltage reference in electronic circuits. The forward voltage drop (about 1.7 V for a red LED or 1.2V for an infrared) can be used instead of a Zener diode in low-voltage regulators. Red LEDs have the flattest I/V curve above the knee. Nitride-based LEDs have a fairly steep I/V curve and are useless for this purpose. Although LED forward voltage is far more current-dependent than a Zener diode, Zener diodes with breakdown voltages below 3 V are not widely available.

The progressive miniaturization of low-voltage lighting technology, such as LEDs and OLEDs, suitable to incorporate into low-thickness materials has fostered experimentation in combining light sources and wall covering surfaces for interior walls in the form of LED wallpaper.

Research and development

[edit]

Key challenges

[edit]

LEDs require optimized efficiency to hinge on ongoing improvements such as phosphor materials and quantum dots.[113]

The process of down-conversion (the method by which materials convert more-energetic photons to different, less energetic colors) also needs improvement. For example, the red phosphors that are used today are thermally sensitive and need to be improved in that aspect so that they do not color shift and experience efficiency drop-off with temperature. Red phosphors could also benefit from a narrower spectral width to emit more lumens and becoming more efficient at converting photons.[114]

In addition, work remains to be done in the realms of current efficiency droop, color shift, system reliability, light distribution, dimming, thermal management, and power supply performance.[113]

Early suspicions were that the LED droop was caused by elevated temperatures. Scientists showed that temperature was not the root cause of efficiency droop.[115] The mechanism causing efficiency droop was identified in 2007 as Auger recombination, which was taken with mixed reaction.[66] A 2013 study conclusively identified Auger recombination as the cause.[116]

Potential technology

[edit]

A new family of LEDs are based on the semiconductors called perovskites. In 2018, less than four years after their discovery, the ability of perovskite LEDs (PLEDs) to produce light from electrons already rivaled those of the best performing OLEDs.[117] They have a potential for cost-effectiveness as they can be processed from solution, a low-cost and low-tech method, which might allow perovskite-based devices that have large areas to be made with extremely low cost. Their efficiency is superior by eliminating non-radiative losses, in other words, elimination of recombination pathways that do not produce photons; or by solving outcoupling problem (prevalent for thin-film LEDs) or balancing charge carrier injection to increase the EQE (external quantum efficiency). The most up-to-date PLED devices have broken the performance barrier by shooting the EQE above 20%.[118]

In 2018, Cao et al. and Lin et al. independently published two papers on developing perovskite LEDs with EQE greater than 20%, which made these two papers a mile-stone in PLED development. Their device have similar planar structure, i.e. the active layer (perovskite) is sandwiched between two electrodes. To achieve a high EQE, they not only reduced non-radiative recombination, but also utilized their own, subtly different methods to improve the EQE.[118]

In the work of Cao et al.,[119] researchers targeted the outcoupling problem, which is that the optical physics of thin-film LEDs causes the majority of light generated by the semiconductor to be trapped in the device.[120] To achieve this goal, they demonstrated that solution-processed perovskites can spontaneously form submicrometre-scale crystal platelets, which can efficiently extract light from the device. These perovskites are formed via the introduction of amino acid additives into the perovskite precursor solutions. In addition, their method is able to passivate perovskite surface defects and reduce nonradiative recombination. Therefore, by improving the light outcoupling and reducing nonradiative losses, Cao and his colleagues successfully achieved PLED with EQE up to 20.7%.[119]

Lin and his colleague used a different approach to generate high EQE. Instead of modifying the microstructure of perovskite layer, they chose to adopt a new strategy for managing the compositional distribution in the device—an approach that simultaneously provides high luminescence and balanced charge injection. In other words, they still used flat emissive layer, but tried to optimize the balance of electrons and holes injected into the perovskite, so as to make the most efficient use of the charge carriers. Moreover, in the perovskite layer, the crystals are perfectly enclosed by MABr additive (where MA is CH3NH3). The MABr shell passivates the nonradiative defects that would otherwise be present perovskite crystals, resulting in reduction of the nonradiative recombination. Therefore, by balancing charge injection and decreasing nonradiative losses, Lin and his colleagues developed PLED with EQE up to 20.3%.[121]

Health and safety

[edit]

Certain blue LEDs and cool-white LEDs can exceed safe limits of the so-called blue-light hazard as defined in eye safety specifications such as "ANSI/IESNA RP-27.1–05: Recommended Practice for Photobiological Safety for Lamp and Lamp Systems".[122] One study showed no evidence of a risk in normal use at domestic illuminance,[123] and that caution is only needed for particular occupational situations or for specific populations.[124] In 2006, the International Electrotechnical Commission published IEC 62471 Photobiological safety of lamps and lamp systems, replacing the application of early laser-oriented standards for classification of LED sources.[125]

While LEDs have the advantage over fluorescent lamps, in that they do not contain mercury, they may contain other hazardous metals such as lead and arsenic.[126]

In 2016 the American Medical Association (AMA) issued a statement concerning the possible adverse influence of blueish street lighting on the sleep-wake cycle of city-dwellers. Critics in the industry claim exposure levels are not high enough to have a noticeable effect.[127]

Environmental issues

[edit]
  • Light pollution: Because white LEDs emit more short wavelength light than sources such as high-pressure sodium vapor lamps, the increased blue and green sensitivity of scotopic vision means that white LEDs used in outdoor lighting cause substantially more sky glow.[55]
  • Impact on wildlife: LEDs are much more attractive to insects than sodium-vapor lights, so much so that there has been speculative concern about the possibility of disruption to food webs.[128][129] LED lighting near beaches, particularly intense blue and white colors, can disorient turtle hatchlings and make them wander inland instead.[130] The use of "turtle-safe lighting" LEDs that emit only at narrow portions of the visible spectrum is encouraged by conservancy groups in order to reduce harm.[131]
  • Use in winter conditions: Since they do not give off much heat in comparison to incandescent lights, LED lights used for traffic control can have snow obscuring them, leading to accidents.[132][133]

See also

[edit]
  • LED tattoo
  • High-CRI LED lighting
  • List of light sources
  • MicroLED
  • Superluminescent diode
  • Perovskite light-emitting diode

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  111. ^ Li, Jinmin; Wang, Junxi; Yi, Xiaoyan; Liu, Zhiqiang; Wei, Tongbo; Yan, Jianchang; Xue, Bin (August 31, 2020). III-Nitrides Light Emitting Diodes: Technology and Applications. Springer Nature. p. 248. ISBN 978-981-15-7949-3.
  112. ^ Gaska, R.; Shur, M. S.; Zhang, J. (October 2006). "Physics and Applications of Deep UV LEDs". 2006 8th International Conference on Solid-State and Integrated Circuit Technology Proceedings. pp. 842–844. doi:10.1109/ICSICT.2006.306525. ISBN 1-4244-0160-7. S2CID 17258357.
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Further reading

[edit]
  • David L. Heiserman (1968). Light -Emitting Diodes (PDF). Electronics World.
  • Shuji Nakamura; Gerhard Fasol; Stephen J Pearton (2000). The Blue Laser Diode: The Complete Story. Springer Verlag. ISBN 978-3-540-66505-2.
[edit]
  • Building a do-it-yourself LED
  • Color cycling LED in a single two pin package,
  • Educational video on LEDs on YouTube

 

 

A residential garage door opener. The motor is in the box on the upper-right.

A garage door opener is a motorized device that opens and closes a garage door controlled by switches on the garage wall. Most also include a handheld radio remote control carried by the owner, which can be used to open and close the door from a short distance.

The electric opener

[edit]

The electric overhead garage door opener was invented by C.G. Johnson in 1926 in Hartford City, Indiana.[1] Electric Garage Door openers did not become popular until Era Meter Company of Chicago offered one after World War II where the overhead garage door could be opened via a key pad located on a post at the end of the driveway or a switch inside the garage.[2]

As in an elevator, the electric motor does not provide most of the power to move a heavy garage door. Instead, most of door's weight is offset by the counterbalance springs attached to the door. (Even manually operated garage doors have counterbalances; otherwise, they would be too heavy for a person to open or close them.) In a typical design, torsion springs apply torque to a shaft, and that shaft applies a force to the garage door via steel counterbalance cables. The electric opener provides only a small amount of force to control how far the door opens and closes. In most cases, the garage door opener also holds the door closed in place of a lock.

The typical electric garage door opener consists of a power unit that contains the electric motor. The power unit attaches to a track. A trolley connected to an arm that attaches to the top of the garage door slides back and forth on the track, thus opening and closing the garage door. The trolley is pulled along the track by a chain, belt, or screw that turns when the motor is operated. A quick-release mechanism is attached to the trolley to allow the garage door to be disconnected from the opener for manual operation during a power failure or in case of emergency. Limit switches on the power unit control the distance the garage door opens and closes once the motor receives a signal from the remote control or wall push button to operate the door.[3]

The entire assembly hangs above the garage door. The power unit hangs from the ceiling and is located towards the rear of the garage. The end of the track on the opposite end of the power unit attaches to a header bracket that is attached to the header wall above the garage door. The powerhead is usually supported by punched angle iron.

Recently another type of opener, known as the jackshaft opener, has become more popular.[when?] This style of opener was used frequently on commercial doors but in recent years has been adapted for residential use. This style of opener consists of a motor that attaches to the side of the torsion rod and moves the door up and down by simply spinning the rod. These openers need a few extra components to function safely for residential use. These include a cable tension monitor, to detect when a cable is broken, and a separate locking mechanism to lock the door when it is fully closed. These have the advantage that they free up ceiling space that an ordinary opener and rail would occupy. These also have the disadvantage that the door must have a torsion rod to attach the motor to.

Types

[edit]

There are six types of garage door openers:

  1. Chain drive openers. These have a chain (similar to a bicycle's) that connects the trolley to the motor.
  2. Belt drive openers use a rubber belt in place of a chain.
  3. Screw drive openers have a long screw inside the track. The trolley connects to this screw.
  4. Direct drive openers have the motor installed inside the trolley and use a gear wheel to guide the trolley along a fixed chain.
  5. Jackshaft openers mount on the wall at either end of the torsion bar.
  6. Roller openers automate roller doors, which roll upward and coil around a drum above the garage entrance, maximizing space.

These openers typically feature two tines that slide into a drum wheel within the roller door mechanism, engaging to smoothly lift or lower the door.

Remote control

[edit]

The first wireless garage door openers were invented and developed by two US inventors at the same time, one in Illinois and the other in Washington state, around 1930. They were unknown to each other.[4]

The first garage door opener remote controls were simple and consisted of a simple transmitter (the remote) and receiver which controlled the opener mechanism. The transmitter would transmit on a designated frequency; the receiver would listen for the radio signal, then open or close the garage, depending on the door position. The basic concept of this can be traced back to World War II. This type of system was used to detonate remote bombs. While novel at the time, the technology ran its course when garage door openers became popular. While the garage door remote control transmitter is low power and has limited range, its signal can be received by other, nearby, garage door openers. When two neighbors had garage door openers, then opening one garage door might open the neighbor's garage door as well.

The second stage of the wireless garage door opener system solved the opening-the-neighbor's-garage-door problem. The remote controls on these systems transmitted a digital code, and the receiver in the garage responded only to that code. The codes were typically set by eight to twelve DIP switches on the receiver and transmitter, so they allowed for 28 = 256 to 212 = 4,096 different codes. As long as neighbors used different codes, they would not open each other's garage doors. The intent of these systems was to avoid interference with nearby garage doors; the systems were not designed with security in mind. Intruders were able to defeat the security of these systems and gain entry to the garage and the house. The number of codes was small enough that even an unsophisticated intruder with a compatible remote control transmitter could just start transmitting all possible codes until he found one that opened the door. More sophisticated intruders could acquire a black box master key that automatically transmitted every possible code in a short time. An even more sophisticated method is known as a replay attack. The attacker would use a code grabber, which has a receiver that captures the remote's digital code and can retransmit that digital code at a later time. The attacker with a code grabber would wait nearby for the homeowner to use his remote, capture the code, and then replay the code to open the door when the homeowner was gone. Multicode openers became unpopular in areas where security was important, but due to their ease of programming, such openers are often used to operate such things as the gates in gated apartment complexes.

An intermediate stage of the garage door opener market eliminated the DIP switches and used remotes preprogrammed to one out of roughly 3.5 billion unique codes. The receiver would maintain a security list of remotes to which it would respond; the user could easily add the unique remote's code to the list by pressing a button on the garage door opener while activating the remote control. A large number of codes made the brute force try-all-possible-digital-codes attacks infeasible, but the systems were still vulnerable to code grabbers. For user convenience, these systems were also backward compatible with the older DIP switch remote codes, but adding an old technology remote to the security list made the garage door opener vulnerable to a brute force attack to find the DIP switch code. The larger code space approach was an improvement over the fixed DIP switch codes but was still vulnerable to the replay attack.

The third stage of garage door opener technology uses a frequency spectrum range between 300-400 MHz and rolling code (code hopping) technology to defeat code grabbers. In addition to transmitting a unique identifier for the remote control, a sequence number and an encrypted message are also sent. Although an intruder could still capture the code used to open a garage door, the sequence number immediately expires, so retransmitting the code later would not open the garage door. The encryption makes it extremely difficult for an intruder to forge a message with the next sequence number that would open the door. Some rolling code systems are more involved than others. Because there is a high probability that someone will push the remote's button while not in range and thus advance the sequence number, the receiver does not insist the sequence number increase by exactly one; it will accept a sequence number that falls within a narrow window or two successive sequence numbers in a much wider window. Rolling code technology is also used on car remote controls and with some internet protocols for secure sites.

The fourth stage of garage door opener systems is similar to third stage, but it is limited to the 315 MHz frequency. The 315 MHz frequency range avoids interference from the land mobile radio system (LMRS) used by the U.S. military.

The following standards are used by units manufactured by Chamberlain (including LiftMaster and Craftsman):

Dates System Color of programming button and LED on unit Color of LED on remote*
1984–1993 8-12 DIP switch on 300-400 MHz white, gray, or yellow button with red LED red
1993–1997 Billion Code on 390 MHz green button with green or red LED green
1997–2005 Security+ (rolling code) on 390 MHz orange or red button with amber LED amber or none
2005–present Security+ (rolling code) on 315 MHz purple button with amber LED none
2011–present Security+ 2.0 (rolling code) on 310, 315, and 390 MHz yellow button with amber LED and yellow antenna wires red or blue

* Does not apply to keyless entry keypads or universal remotes.

Recent Chamberlain garage door openers that have Security+ 2.0 features also use a special serial protocol on wired connections rather than a simple switch closure.[5]

The following standards are used by units manufactured by Overhead Door Corporation and its subsidiary The Genie Company†:

Dates System
1985–1995 9–12 DIP switch on 360, 380, or 390 MHz[6][7]
1995–2005 Intellicode/CodeDodger (rolling code) on 390 MHz
2005–present Intellicode/CodeDodger (rolling code) on 315 MHz
2011–present Intellicode 2/CodeDodger 2 (rolling code) on 315 and 390 MHz

Note: There are no standard color codes for the learn button or LED on units manufactured by Overhead Door or Genie. All accessories made for later versions of Genie Intellicode and Overhead Door CodeDodger are backward compatible with previous generations of Intellicode and CodeDodger.

Cloning garage door opener remotes

[edit]
A typical photo of both the outer case and inner circuit of a garage door opener remote control.

Many garage door opener remote controls use fixed-code encoding which use DIP switches or soldering to do the address pins coding process, and they usually use pt2262/pt2272 or compatible ICs. For these fixed-code garage door opener remotes, one can easily clone the existing remote using a self-learning remote control duplicator (copy remote) which can make a copy of the remote using face-to-face copying.

Additional features

[edit]

Additional features that have been added over the years have included:

  • Automatic courtesy lights that turn on when the door opens (or via motion sensors) and automatically turn off after a preset delay
  • A remote lockout feature, which turns off the radio receiver while one is on vacation or away for an extended time.
  • The availability of accessories has increased, including such features as wireless keypads, key chain remotes, and solenoid-operated deadbolts to lock the door itself.
  • Automatic door closing feature, which after a fixed time by the owner, closes the garage door to prevent theft.

More sophisticated features are also available, such as an integrated carbon monoxide sensor to open the door in case of the garage being flooded with exhaust fumes. Other systems allow door activation over the Internet to allow home owners to open their garage door from their office for deliveries.

Another recent innovation in the garage door opener is a fingerprint-based wireless keypad. This unit attaches to the outside of the garage door on the jamb and allows users to open and close their doors with the press of a finger, rather than creating a personal identification number (PIN). This is especially helpful for families with children who may forget a code and are latchkey kids.

Safety

[edit]
Electric eye for safety

The garage door is generally the largest moving object in a home. An improperly adjusted garage door opener can exert strong and deadly forces and might not reverse the garage door in an emergency. The manufacturer's instructions provide guidance to the user on the proper adjustment and maintenance of the opener.

Garage door openers manufactured and installed in the United States since 1982 are required to provide a quick-release mechanism on the trolley that allows for the garage door to be disconnected from the garage door opener in the event of entrapment.[8] Garage door openers manufactured since 1991 are also required to reverse the garage door if it strikes a solid object.[9][10]

In the United States, the Consumer Product Safety Improvement Act of 1990 required that automatic residential garage door operators manufactured on or after 1 January 1991 conform to the entrapment protection requirements of the 1988 version of ANSI/UL standard 325.[11] A requirement for redundant entrapment-prevention devices was added in 1993; such a system can use an electric eye, a door edge sensor, or any other device that provides equivalent protection by reversing the travel of the closing door if an object is detected in its path.[12][13]

California Senate Bill No. 969

[edit]

In California, Senate Bill No. 969 requires that any automatic residential garage door opener that is manufactured for sale, sold, offered for sale, or installed in a residence to have a battery backup function that is designed to operate when activated because of an electrical outage.[14] The bill went into effect on July 1, 2019. Under the bill, any automatic garage door opener that is in violation is subject to a civil penalty of $1000.

The bill was passed by Gov. Jerry Brown on Sept. 21, 2018, in response to the 2017 California Wildfires in which at least 5 individuals lost their lives because they could not open their garage door when the power went out.[15]

The Door and Access Systems Manufacturers Association International opposed the bill arguing that garage door openers with backup batteries require regular maintenance and that the bill should be amended to make this clear. In addition, they said that "garage door openers with backup batteries are not designed to serve as life safety devices, and should not be relied upon to prove a means of egress from a garage during an electrical outage."[16]

The bill passed, despite most garage doors having a release pull cord.

References

[edit]
  1. ^ Robert J Girod (2014). "Garage Door Openers - High-tech Burglary". Advanced Criminal Investigations and Intelligence Operations: Tradecraft Methods, Practices, Tactics, and Techniques. Taylor and Francis. p. 90. ISBN 9781482230741.
  2. ^ "Aids To Modern Living - Garage Doors". Popular Science: 137. December 1946.
  3. ^ Castro, Diane. "The Complete Garage Door System". Regency Conference Center. Retrieved 10 March 2020.
  4. ^ "Widely Separated Inventors Invent Garage Door Openers By Radio Impulses". Popular Science: 32. February 1931.
  5. ^ "Will my older accessories work with the new line of Security+ 2.0 garage door openers?". alldaygaragerepair.com. Retrieved 2017-06-23.
  6. ^ Willmes, Dave. "My Overhead Door Opener Doesn't Work with this Universal Remote". www.overheaddooronline.com. Retrieved 20 October 2016.
  7. ^ "FCC ID BSH8YN106546 by Overhead Door Corporation". FCCID.io. Retrieved 20 October 2016.
  8. ^ "Falling Garage Doors — A Crushing Concern". Garage Door Child Safety.
  9. ^ "Non Reversing Garage Door Openers a Hazard" (PDF). U.S. Consumer Product Safety Commission.
  10. ^ "Garage Door System Safety Guidelines". Door & Access Systems Manufacturers Association International. Archived from the original on 2008-12-23.
  11. ^ Garage Door Operators • CPSC
  12. ^ Non-Reversing Automatic Garage Door Openers Are a Hazard • CPSC
  13. ^ 16CFR1211
  14. ^ "Bill Text - SB-969 Automatic garage door openers: backup batteries". leginfo.legislature.ca.gov. California Legislative Information. Retrieved 6 September 2019.
  15. ^ "New California Law Could Cost You $1000 in Fines". Clark's Garage Door. 4 September 2019. Retrieved 6 September 2019.
  16. ^ "California Mandates Battery Backup With All GDOS - Experts Cite Problems With The Legislation" (PDF). dasma.com. DASMA. Retrieved 6 September 2019.
[edit]
  • Official FCC notification on garage opener frequencies (PDF)
  • Garage Door Opener Safety Tips (Washington Post)
  • Safety Commission Rules For Automatic Garage Door Openers - U.S. Consumer Product Safety Commission. CPSC, 1992
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Driving Directions in Will County


Driving Directions From The Haley Mansion to Overhead Door Company of Joliet
Driving Directions From Clarion Hotel & Convention Center Joliet to Overhead Door Company of Joliet
Driving Directions From Golden Corral Buffet & Grill to Overhead Door Company of Joliet
Driving Directions From Honorable Edward A Burmila Jr to Overhead Door Company of Joliet
Driving Directions From First American Bank to Overhead Door Company of Joliet
Driving Directions From Joliet Iron Works Historic Site to Overhead Door Company of Joliet
Driving Directions From Joliet Iron Works Historic Site to Overhead Door Company of Joliet
Driving Directions From Fox Museum to Overhead Door Company of Joliet
Driving Directions From DuPage Children's Museum to Overhead Door Company of Joliet
Driving Directions From Will County Historical Museum and Research Center to Overhead Door Company of Joliet
Driving Directions From Will County Historical Museum and Research Center to Overhead Door Company of Joliet
Driving Directions From Pilcher Park Nature Center to Overhead Door Company of Joliet

Reviews for Overhead Door Company of Joliet


Overhead Door Company of Joliet

Kelley Jansa

(5)

We used Middleton Door to upgrade our garage door. We had three different companies come out to quote the job and across the board Middleton was better. They were professional, had plenty of different options and priced appropriately. The door we ordered came with a small dent and they handled getting a new panel ordered and reinstalled very quickly.

Overhead Door Company of Joliet

Hector Melero

(5)

Had a really great experience with Middleton Overhead Doors. My door started to bow and after several attempts on me fixing it I just couldn’t get it. I didn’t want to pay on something I knew I could fix. Well, I gave up and they came out and made it look easy. I know what they are doing not to mention they called me before hand to confirm my appointment and they showed up at there scheduled appointment. I highly recommend Middleton Overhead Doors on any work that needs to be done

Overhead Door Company of Joliet

Owen McCarthy

(5)

I called the office just by chance to see if there was an available opening for a service call to repair a busted spring. Unfortunately I didn’t catch the name of the person who answere, but she couldn’t have been more pleasant and polite. She was able to get a tech to my house in an hour. I believe the tech’s name was Mike and he too was amazing. He quickly resolved my issue and even corrected a couple of things that he saw that weren’t quite right. I would recommend to anyone and will definitely call on Middleton for any future needs. Thank you all for your great service.

Overhead Door Company of Joliet

Andrea Nitsche

(4)

Scheduling was easy, job was done quickly. Little disappointed that they gave me a quote over email (which they confirmed was for labor and materials), but when they finished it was just over $30 more. Not a huge deal, but when I asked why, I was told they gave me an approx cost and it depends on what is needed. I get that in general, however, they installed the door and I gave them my address and pics of the existing prior to getting a quote. I feel like they could have been more upfront with pricing. And just a heads up, it was pricey... Had them change the weather stripping, from ringing my doorbell to pulling out my driveway when done was literally 20 mins, cost was just over $260 😬

View GBP

Frequently Asked Questions

To program a new remote, press and release the Learn button on the control panel. Within 30 seconds, press and hold the desired button on your remote until you hear a click or see an indicator light flash, confirming successful programming.
Check for obstructions blocking the doors path and ensure sensors are aligned properly. If clear, adjust the travel limits on the control panel by following your manufacturers instructions to ensure proper closure.
Typically, you can reset by unplugging the motor unit for about 30 seconds, then plugging it back in. Reconnect any backup batteries if applicable, and test operation using both wall controls and remotes.
Yes, most systems have a lock feature accessible via the wall-mounted control panel. Activate this by locating and pressing the lock button (often labeled as “Lock” or shown with a padlock icon) until an indicator light confirms its engaged.