Photocurrent

                                         Photocurrent is the current that flows through a photosensitive device, such as a photodiode, as the result of exposure to radiant power.

The photocurrent may occur as a result of the photoelectric, photoemissive, or photovoltaic effect.

The photocurrent may be enhanced by internal gain caused by interaction among ions and photons under the influence of applied fields, such as occurs in an avalanche photodiode (APD).

When a suitable radiation is used, the photoelectric current is directly proportional to the intensity of the radiation ..