Q9 of 805 Page 1

Name the optoelectronic device used for detecting optical signals and mention the biasing in which it is operated. Draw its I- V characteristics.

The optoelectronic device used for measuring optical signals is Photo-diode.


A photodiode is also a special type of a junction diode which is used to detect optical signals. It has a p – n junction which is reverse biased and is made from the photosensitive material.


When a reverse bias is applied to such a diode, it causes a change in the intensity (I) of light, which reciprocally changes the current in the photodiode also.


I-V characteristics are:



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