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Light-Sensitive Diodes

If light of the proper wavelength is incident on the depletion region of a diode while a reverse voltage is applied, the absorbed photons can produce additional electron-hole pairs. Photo-diodes or photocells can receive frequency-modulated light signals. LEDs and photodiodes are often used in optical communication as receiver and transmitter respectively.

Doug Gingrich
Tue Jul 13 16:55:15 EDT 1999