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The article provides an overview on the applications and types of light-emitting diode (LED). It defines LED as a semiconductor which generates visible light of a particular color. It presents a brief history of LED wherein the first LED was attributed to researcher Nicholas Holonyak circa 1962. It adds that LED has evolved over the years proving to be viable in several applications with different types including organic LEDs, infrared (IR) LEDs, and ultraviolet (UV) LEDs.

The article focuses on the significance of white light emitting diodes (LEDs) for green illumination. It notes that a LED light source produce 900 light output lumens by using about 10-12 Watts. It points out that the cost of LEDs for indoor and outdoor lighting is higher than the incandescent and fluorescent light sources. An understanding of color rendering index (CRI) or color rendition index is also considered relevant.

The article focuses on the importance of organic light-emitting diode (OLED) technology for the needed light of the economic tunnel. It mentions that OLED continues to support the industry's current economic struggles, carving out lucrative applications in various display and lighting applications. It notes that active-matrix OLED displays offer a thinner form factor, a wider viewing angle, a faster response time and lower power dissipation.

The article focuses on the use of light emitting diodes (LED) in office buildings and city streets. LED illumination for building interiors and outdoor public spaces opened up new opportunities for electronic designers. In cities at the southern end of San Francisco Bay in California, the LED lighting will replace sodium-vapor lights. It is helpful to analyze a specific design to get a sense of all the considerations involved in dimming LED.

The article provides information on the implementation of a platform created in Adobe Flash through building a real-time graphical user interface. Ajax was being used to have updates on the portions of the page that need updating which requires continuous polling of the network device server to check for updates. It is noted that Flash is a very interesting option with significant advantages for the light emitting diodes and switches on the development board. The process is done through an application in the Web browser and creating a permanent transmission control protocol connection back to the NetBurner device.

The article reports on the growing demand for light-emitting diodes (LEDs). It is said that LEDs are widely utilized across industrial, commercial, and residential settings. This has caused component makers and distributors to speed up building and introducing the newest solutions for lighting manufacturers.

The article discusses the significant characteristics of light-emitting diodes (LED) and organic LEDs (OLED) on the lighting option of choice in the U.S. LEDs offer life and greater efficiency than those other technologies, which is why they are seeing rapid adoption in buildings, parking lots, plants, streets, stadiums, airports and other large facilities. The U.S. Department of Energy is putting some funds into this growth with its Solid State Lighting (SSL) plan, which spans the years 2000-2020. Increases in solid-state lighting luminous efficiencies are quite dramatic when compared to other conventional light sources, which have reached roughly even plateaus with no significant additional growth expected.

Features the use of inverter integrated circuits to drive electroluminescent lamps (EL). Using EL lamps for backlighting and panel illumination in pagers and wristwatches; Improving the reliability of EL technology; Encapsulating the phosphor particles in glass; Eliminating moisture absorption; Comparison of EL-lamp-inverter technologies; Transformer-based inverters; Inductor-based inverters.

The article reports on the technology Li-Fi or light fidelity used for accessing wireless networks. It involves encoding data into visible light instead of the radio waves used by traditional wireless technology like Wi-Fi. Li-Fi takes advantage of the fact that light-emitting diodes used in light bulbs are semiconductor devices. The same electric current sent through them to produce light can be switched at extremely fast speeds, flickering the light to encode parallel data streams.

The article discusses various issues related to high power light emitting diodes (LEDs). It is stated that the high-power technology will require a heat-sink and metal-core printed-circuit board (MCP-CB) to ensure the junction temperature isn't high enough to cause a loss in efficacy, a decrease in life hours, or color degradation.

The article discusses the techniques employed by Novaled AG in developing its white-light-output organic light-emitting diode (OLED). The company has used proprietary organic materials and flat light-coupling method of light extraction to achieve OLED's efficiency of 36 lumens per watt (lm/W). Gildas Sorin, chief executive officer (CEO) of Novaled, asserts that the company has managed to overcome the challenges involved in improving light outcoupling results and external quantum efficiency.

The article presents the electronic design of a switch mode-regulator light emitting diode (LED) driver. It states that the circuit is designed for alternating current (ac) lighting that requires a high power factor (PF). The ac source also plays an important factor in creating voltage and current input waveforms with a large phase shift and very low power factor.

The article focuses on the performance capabilities and design integration aspects of high-power light-emitting diode (LEDs). It notes that LED represents a significant advance in lighting technologies and offers greater design flexibility than alternative lighting options. Moreover, several common perceptions about high-power LED technology are also presented.

The article evaluates several light emitting diodes (LEDs) including 3-W white LEDs from Avago Technologies Ltd., Osram Ostar high-power LED from Osram Opto Semiconductors Inc., and oval LEDs from Cree Inc.

The article provides information on the role of optical bonding and surface treatments in improving thin-film-transistor (TFT) light emitting diode (LCD) display. It states that optical bonding and anti-glare (AG) or anti-reflective (AR) surfaces can be added to the overlays to maintain the performance of the product. The AG and AR surface treatments can also improve display legibility without impacting power consumption. In connection, contrast ratios also help determine legibility displays in which 7:1 minimum contrast ratio is required on full-color graphic displays.

The article provides information on the concept of the design of high-brightness light emitting diodes (HBLED). It states that HBLEDs are more efficient and longer lifespan since these hysteretic controllers are inexpensive and require no compensation networks. These controllers have pulse-width-modulator (PWM) input that enables a train of varying duty cycle to provide the dimming function of HBLEDs. In connection, a circuit board showing the hysteretic controllers, the five high-brightness light emitting diodes (LED) and triangle wave is also presented in the article

The article presents the features of the white light-emitting diode (LED). In portable applications, white LEDs are often powered by sealed lead acid (SLA) batteries having a typical output of 12 volts. The driver circuit uses an SG1524 pulse-width modulation (PWM) switching regulator (U1) operating in boost configuration. This configuration enables U1 to produce a maximum output of about 40 volts, which can drive a string up to 11 serially connected 1-W white LEDs. Because of the high power dissipation, the LEDs must be mounted with a suitable heatsink.

The article presents a circuit configuration that illuminates a string of seven white light emitting diodes (LED) using stack of batteries. The brightness of these diodes could be slightly adjusted. The circuit is best described in two parts, the boost circuit function and the control circuit. Procedures on how the circuit produces the constant illumination of LED through flyback action is discussed. The importance of using matched batteries in the battery stack as well as the cause of overheat and leakage of milky acid is also discussed.

This article presents solutions to frequently asked questions related to Light emitting Diodes (LEDs) published in the January 2005 issue of "Electronic Design." The trend for color displays in handhelds has produced a parallel move to white LEDs for LCD backlighting. White LEDs provide the desired appearance for backlighting color LCDs. They're also more rugged and efficient, simpler to drive, and smaller, thinner, and far less noisy than the cold-cathode florescent tubes previously used for backlighting.

The article offers information on the success of the light emitting diodes (LEDs). It states that LEDs are more energy efficient and cost less in the long run, but they have a much higher upfront cost compared to the significantly less efficient traditional light bulb. It states cold cathode fluorescent lamps (CCFLs) provide more configuration options than incandescent bulbs, but their support hardware and general construction limit their possible deliverables.

The article forecasts the positive application of light emitting diodes (LEDs) in illumination. Databeans Inc. expects the market for LEDs to increase with an average of 23% on the following years. It foresees LED revenues to reach 1.8 billion by 2013. It predicts that by 2012, 24 billion LEDs will be used for active outdoor displays. It also reports an 11% increase of the LED market for 2008.

The article offers information on Light Emitting Diodes (LED) candles. It informs that these candles are improved electronic birthday candles with better blow out simulation. It also presents a figure illustrating how Charlieplexing, LED's multiplexing scheme permits the eight-pin microprocessor control units (MCU) to control 20 LEDs, mimicking as birthday candles.

The article discusses the shift of logic-level signals to --48-V systems to achieve proper dimming control for light emitting diode (LED) driver in the U.S. It states that the circuit uses a 65-V hysteretically controlled LED driver and connect its ground pins to --48 V. In addition, it incorporates high-voltage pnp transistor to operate at approximate unity gain.

The article focuses on the benefits associated with the use of light emitting diodes (LED) in many different types of outdoor applications. If LED lighting is employed in higher power, white-light applications, the overall light pollution caused by lighting will decrease. LED-based lamps are easy to turn on and off, and they dim down to one percent. They also provide extremely directional light rather than emitting light in all directions.

The article focuses on the significance of common-anode configuration in setting up for triple-output light emitting diode (LED) drivers. It notes that the configuration can reduce the number of wires connected between the LED module and its driver from 2N to N+1, where in is the number of LED strings in the module. The circuit showing the components for configuring the said multi-string LED modules is also presented.

The article focuses on the simple ambient light sensors that control white-light emitting diode (LED). A common application of this technology would be the brightness control for cellphone backlighting, that improves in visibility on a very sunny day. The circuit which uses the IA2505 four-channel white LED and the variations of the resistor (RSET) source current with changes in photo emissions are also presented in graphs and diagrams.

The article discusses the concept of a camera privacy flash warning created by adding logic gates to light emitting diodes (LED) driver. One can implement a combination privacy- and full-flash light using simple logic gates along with an LED driver. The circuit uses an IA2505 high-efficient, low-cost, four-channel LED driver current source, designed for flash and back- lighting LEDs. The circuit's LED current can be set from 5 milliamperes to 80 milliamperes (mA) on each channel, and LED pulse current can be as high as 200 mA per channel for a duration of 20 millisecond or less.

The author reflects on the significance of light emitting diodes (LED) on digital light processor (DLP) high-definition television (HDTV) applications. He evaluates the DLP Discovery Digital Micromirror Device (DMD) from Texas Instruments Inc.'s and the Phatlight LEDs from Luminus Devices; and, the impact of these devices on Samsung's 50-inches HLT5089S display. He also stresses that DLP technology has dominated projection systems, including home theater environments and movie theaters.

The article reports on the claim of Osram Opto Semiconductors Inc. to have set a world record in the research for brightness and efficacy of white light-emitting diodes (LEDs). Osram has developed a white-LED prototype using 1-mm2 chips capable of delivering a peak brightness value of 155 lumens with an efficacy of 136 lumens per watt. The company's chief executive officer, Rüdiger Müller said the successful combination of know-how in different fields has resulted to the new records in efficiency and brightness. He added that starting with the light converter, the company will gradually move new developments into production.

The article provides information on the use of LT347 light-emitting diode (LED) driver channels. It states that such LED driver can handle four LED strings and the remaining channels of the driver can be used to produce regulated power supplies which eliminate additional circuitry required for a separate power supply. The fourth channel of such driver can be used for liquid crystal display (LCD) panel that requires a bias voltage. Electronic diagram that depicts the electronic design for such LED driver is presented.

The article focuses on the lighting technologies used in the design of the New Year's Eve ball featured in the Time Square in New York City on December 31, 2007. The new ball is noted to reflect the energy-conscious culture as it was made of light emitting diodes (LEDs) and Waterford crystals which are energy efficient and allow the ball to increase its brightness. It contains the 9576 Luxeon K2 LEDs donated by Philips Lumileds, and utilized Focus Lighting's solid-state lighting system and Lapp USA's FD 855 P power supply.

The article evaluates several electronic equipment including the electronic display inlay designed by Aveso Inc., bi-color light-emitting diodes (LED) assembly manufactured by Data Display Products (DDP), and the white organic LED from Novaled AG.

The article focuses on the latest innovation in the manufacture of light-emitting diodes (LEDs). Manufacturers are now creating LEDs which can be used more than as function and alert indicators and can replace incandescent and fluorescent fixtures as well as automotive headlights and signals. LEDtronics are now offering aqua green and red-green-blue (RGB) LEDs that promise to shine through the brightest blaze of sunshine. Cree Inc. is also developing green and blue LEDs that outshine their predecessors in the family. Furthermore, Osram Opto Semiconductors Inc. is also manufacturing the world's brightest single-chip, surface-mount LED which can achieve up to 250 lumens.

The article focuses on the plan by Sony Corp. to start selling its organic light emitting diode (OLED) television in Japan in 2007. It was cited that the company's 11-and-27-inch OLED television was a hit at the Consumer Electronics Show in Las Vegas in January 2007 and at a display forum in Tokyo. Unlike liquid crystal display (LCD) screens, which require fluorescent backlighting source, OLEDs utilize electrophosphorescent materials that glow when an electric current passes through them. Moreover, one challenge for Sony, which began its OLED display research in 1998, was the creation of displays which are large enough for television. Meanwhile, the company has not yet released information on unit targets or pricing for the product.

The article presents information on the design of a light emitting diode (LED) display system sent by the readers of the periodical. Most of the LED displays are limited to low output currents. The approach described here uses one 74ALS374 or 74AS374 octal latch, wired as a shift register, per digit. By the use of this approach, one can generate the numbers 0 through 9, and leading zero suppression. Also, any other combination of seven segments not available to seven-segment decoder-type drivers can be created. One can also interface this type of display to a microcontroller using one or two output pins.

This article presents information on high-power light emitting diodes (LEDs) drivers. The advent of high-power LEDs that can replace incandescent bulbs has produced a need for circuits that efficiently match the LEDs to available power sources. The circuits should also be able to regulate and control the LED light output, despite variations in output voltage from the power source. This idea's circuit starts and operates a 1-A LED from a voltage that ranges from 2.7 V minimum to 16.5 V maximum. Operation over that range is stable and smooth, even with more than 1Ω of internal resistance at the power source.

This article presents information about an electronic circuit constructed by using the light emitting diodes (LEDs) in reverse mode to capture light and emit a small voltage. Although typically employed as a display, an LED can be used in reverse to capture light and emit a small voltage. With a bright white light, some LEDs can output over 1.0 volts. Depending on the color, the LED can be used to discriminate against other colors. A green LED will produce a voltage output with a green light source, but almost no voltage with a red light source.

The article focuses on Cypress Semiconductor Corp.'s PSoC Express graphical design system, that targets the low end with its 8051-based, mixed-signal PSoC microcontroller. The PSoC chip contains a collection of analog and digital building blocks around a processor and memory core. Developers can create custom logic PSoC Designer, but it takes expertise. Likewise, application code needs to be written to take advantage of this custom configuration. PSoC Express takes a higher-level approach by using a set of standard peripherals that can be mapped onto the building blocks. Peripherals can be linked together using a simple table-driven interface. Buttons can be joined to controls or light emitting diode.

Presents letters to the editor about electronics. Discussion of increasing uses of Light Emitting Diodes; Comment on an article inquiring eyelet usage in personal computer boards; Issues related to soldering in electronics.

This article presents a novel approach to high-power white light-emitting diode (LED) driving using a standard-boost converter integrated circuit in a voltage-reducing mode. Using a boost-mode topology simplifies design when compared to a voltage-mode buck converter. One added feature of the topology is that as the current flows through the LED, there is a reduction in the peak-average current ratio in the LED.

This article presents information on various types/models of liquid crystal display and light emitting diodes. Features, pricing and manufacturer of the new products are indicated.

The article presents a way to synchronize an array of standard flashing light emitting diodes (LEDs) using only two additional components. A flashing LED is required to "set the pace" of the standard "slave" LEDs. When the flashing LED turns on, its corresponding current is sensed by the transistor via the resistor. The transistor's collector current then drives the standard LEDs. Flashing LEDs incorporate internal electronics for oscillation offer embedded applications the advantage of size. However, designs that require multiple flashing LEDs are impeded by the reality that individual flashing LEDs are automatons and will blink asynchronously. In addition, these flashers can be an order of magnitude more expensive than their nonflashing brethren.

Features the low-cost light emitting diodes engines developed by Lamina Ceramics Inc. in the U.S. Availability of the lights; Level of brightness of the diodes; Price.

Reports that Hopewell Junction, New York-based display manufacturer eMagin Corp. has received a U.S. patent for an organic light-emitting diode (OLED) design as of February 4, 2002. Features of the OLED design developed by the company; Contact information.

Features the SP4414, a small electroluminescent lamp driver that operates with an external clock source. Availability; Price; Ordering information.

Reports on the development of a white-light emitting device by designers at Siemens AG's Siemens Semiconductors division. Capability of delivering up to 20 millicandela of light; Other features of the light; Versions of the product.