An optical source has a spectral width of 850 nm What type o

An optical source has a spectral width of 850 nm. What type of optical source is it likely to be? All of these LED None of these Wideband source Coherent source Laser Diode

Solution

answer is none of these

LED has spectral width of

For 800-900nm operation

spectral width is about 25-40nm

• For 1100-1700nm operation

spectral width is about 50-160nm

laser diode is a coherent source its spectral width is

Spectral width

– 1nm at 850nm

– 3nm at 1300 and 1550nm

wideband source has typical 100nm spectral width