Light-Emitting Diodes (LED differs from other light sources, such as incandescent and flourescent lamps, in the way they generate white light.

People are accustomed to lamps that emit white color.

But what does that realy mean? What appears to our eyes as white is actually a mix of diffenrent wavelengths in the visible portion of the electromagnietic spectrum.

The diagram below illustrates visible light as one small portion of overall electromagnetic spectrum.

Electromagnetic radiation in wavelengths from about 380 to 770 nanometers is visible to the human eyes.