Search results
Results from the WOW.Com Content Network
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 ...
To drive the LED, a computer-controlled pin is turned on and off at the right time. Cross-talk from the LED to the receiving PIN diode is extreme, so the protocol is half-duplex. To receive, an external interrupt bit is started by the start bit, then polled a half-bit time after following bits.
Remote controls and IrDA devices use infrared light-emitting diodes (LEDs) to emit infrared radiation which is focused by a plastic lens into a narrow beam. The beam is modulated, i.e. switched on and off, to encode the data. The receiver uses a silicon photodiode to convert the infrared radiation to an electric current. It responds only to the ...
A single multicolor module may have three individual LEDs within that package, one each of red, green and blue, to allow many colors or shades of white to be selected, by varying the brightness of the individual LEDs. LED brightness may be increased by using a higher driving current, at the cost of reducing the device's lifespan.
LED development began with infrared and red devices made with gallium arsenide. Advances in materials science have enabled making devices with ever-shorter wavelengths, emitting light in a variety of colors. LEDs are usually built on an n-type substrate, with an electrode attached to the p-type layer deposited on its surface.
An infrared spectroscopy correlation table (or table of infrared absorption frequencies) is a list of absorption peaks and frequencies, typically reported in wavenumber, for common types of molecular bonds and functional groups.
Infrared heaters can be operated in vacuum or atmosphere. One classification of infrared heaters is by the wavelength bands of infrared emission. Short wave or near infrared for the range from 750 nm to 1.4 μm; these emitters are also named "bright" because still some visible light is emitted; Medium infrared for the range between 1.4 μm and ...
The following other wikis use this file: Usage on bs.wikipedia.org Svijetleća dioda; Usage on ckb.wikipedia.org ئێڵ ئی دی; Usage on en.wikibooks.org