Category Archives: LEDS

Connecting to the web via LEDs: Li-Fi

Connecting to the Internet is best done through copper wire or high-speed wireless connections. Not many are aware of an additional method – using light beams. This is accomplished not by the usual optical fiber stuff, but by using LEDs. Communication with lights is nothing new - it has been done before. The Scottish scientist, Sir Alexander Graham Bell had invented an arsenal of instruments for communication and these included Photophones. The first instruments to use light for communication Read more [...]

Choose the color of your led

To indicate the hue of a specific type of light source, the standard procedure is to measure its color temperature in degrees Kelvin. For example, for suggesting realistic colors of lights in a 3D scene, you can use a Color Temperature chart. Typically, the white balance of a video camera or a film stock is used as the base for relating visible colors. For this, two settings are used most commonly. The first is the indoor color balance, set at 3200K and the other is the daylight color balance, set Read more [...]

Is there anything better than OLEDs?

Almost everyone uses a smartphone today and the displays are getting ever bigger. Larger screens are a pleasure to watch, but difficult to put inside a pocket. Therefore, Qibing Pei, a professor of materials science, is researching highly flexible and stretchable OLED displays that could allow a small elastic OLED smartphone to fit easily into one's pocket and the screen could be expanded when viewing. That would certainly be a great help if successful, but in the meantime, there is something else, Read more [...]

Battle the Sun with a 21W LED and a Raspberry Pi

Lighting up an LED or an array of LEDs and controlling their brightness is a simple affair with the tiny credit card sized single board computer popularly known as the Raspberry Pi or the RBPi. The RBPi runs a full version of Linux and you can use it to drive an array of bright LEDs with it. If you construct it like Jeremy Blum did - he put up the LEDs on his graduation mortar board and wore the RBPi on his wrist on his graduation day - you can be sure of getting a lot of excited remarks from friends Read more [...]

What is LED EOS failure?

LEDs, being semiconductor components, are susceptible to failure if overstressed electrically. This is true regardless of the manufacturer and electrical overstress or EOS is the leading cause of failure of LEDs. In fact, LED components are subject to transient conditions that can cause EOS and subsequently result in a catastrophic failure. Like all semiconductor components, LEDs too have their maximum specifications of voltage, current and power. An exposure beyond the maximum current or voltage Read more [...]

Designing Intelligent Lighting Systems with Constant Current LED Drivers

Sunpower LLP of UK has launched 25W constant current LED Drivers that facilitate designing of low wattage project style lighting and intelligent LED lighting control systems. The company has added the driver christened LCM-25 to its existing LCM series of constant current LED drivers for 60W and 40W. Apart from maintaining its output at a constant current while meeting the LED needs, the driver can be set up at varying levels ranging from 350mA to over an Ampere with the help of a built-in DIP switch. Read more [...]

ByteLight LEDS provide location based service

Not so very long ago, the friendly neighborhood supermarket had a security guard who would greet you in recognition and the store assistants could guide you since they knew what you usually bought. However, the introduction of huge shopping malls with their multiple floors has done away with anyone able to recognize even frequent customers, making the whole affair of shopping completely impersonal. However, things are about to change. GE Lighting and ByteLight are harnessing the next generation Read more [...]

Raspberry Pi Lights up an RGB LED Matrix Panel

Colorful LED screens are a joy to watch. Bright LEDs making up a 16x32 display are not only easy-to-use, but also low cost – you may have seen such displays in the Times Square. Controlling such a display is simple if you use the low-cost, versatile, credit card sized single board computer, the Raspberry Pi or RBPi. Although the wiring is simple, the display is quite demanding of power when displaying. The items you need for this project are a 16x32 RGB LED Matrix Panel, Female-to-Female jumper Read more [...]

The Eavesdropping LED Street Lights of Las Vegas

LEDs have come into our daily lives almost without our noticing them and suddenly they are everywhere. People visiting Las Vegas may notice that streetlights there are LED based. That in itself may not be very surprising, except that the LED streetlights in Las Vegas are able to not only entertain with videos and music, they care about what you say. Furthermore, LED lights even watch while you speak your thoughts. That gives credence to the inevitable quip: “What happens in Vegas doesn't stay in Read more [...]

Making City Streetlights Smart with DALI

Big cities are changing over to LED lights for illumination of their streets. They find this to be a smart solution in terms of cost-reduction and efficiency. STMicroelectronics is taking an important next step by adopting LEDs for street illumination. They are doing this in conjunction with smart power supplies that turn the LED street lamps into intelligent devices. For example, the streetlamps reduce their brightness as the sun rises while gradually increasing their brightness with failing daylight. Read more [...]