Time:2008-3-10 9:52:10 From:LED GLOBO ONLINE Message center
Definition
A light-emitting diode (LED) is a semiconductor diode that emits incoherent narrow-spectrum light when electrically biased in the forward direction.
Basic principles of LED (Light Emitting Diodes)
Basic principles of LED (Light Emitting Diodes)
An LED consists of several layers of semiconducting material
When an LED is operated with DC voltage light is generated in the active layer
The generated light is radiated directly or by reflections
In contrast to lamps, which emit a continuous spectrum, an LED emits light in a certain color
The color of the light depends on the used material
Two systems of material (AllnGaP and InGaN) are used in order to produce LED with a high luminance in all colors from blue to red and also in white (luminescence conversion). Therefore different voltages are necessary in order to operate the diode in conducting direction
The production of white light
To produce white light, the light of blue LEDs is passed through yellow phosphors. The composition of the phosphor determines the light color.
The Chip Level Coating (CLC) process developed and patented by OSRAM ensures a degree of homogenity in the light produced that other processes cannot achieve.
By selecting appropriate white LEDs, it is possible to offer LED systems with the same light colors as fluorescent lamps (Warm White, Neutral White and Daylight).
[Close Window][Print Page]This information is only for your reference; authenticity is not approved. No citation is allowed without permission.
