Image sensors and optical devices

What problem tends to occur when the pixel size of an image sensor is reduced?

  1. AThe number of pixels decreases
  2. BThe light received and charge stored per pixel decrease, so sensitivity and dynamic range tend to fall
  3. CColor filters become unnecessary
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Answer: B. The light received and charge stored per pixel decrease, so sensitivity and dynamic range tend to fall

Smaller pixels allow more pixels on the same sensor, but the light entering each pixel and the maximum charge the photodiode can store both decrease. As a result, noise becomes more visible in dark scenes and highlights blow out more easily in high-contrast scenes.

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