Image sensors and optical devices

In each pixel of a CMOS image sensor, which element converts light into charge?

  1. APhotodiode
  2. BLight-emitting diode (LED)
  3. CZener diode
Show answer and explanation

Answer: A. Photodiode

In an image sensor pixel, the photodiode absorbs incoming light to create electron-hole pairs and stores charge according to the amount of light. In a CMOS image sensor, that charge is converted to a voltage by transistors within the pixel and read out.

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