Photo Resistor basics | What is Photo Resistor Dark Resistance

This page describes photo-resistor definition, photo-resistor dark resistance basics and equation of photo-resistor dark resistance.

What is Photo Resistor?:
The device whose resistance decreases with the increase in incident light is known as Photo-resistor. It is also known as LDR (Light Dependent Resistor) or Photoconductor. When the light falling on its surface increases, its resistance decreases leading to current flow in the circuit.

Photo Resistor

The figure-1 depicts typical components in a photoresistor.

What is Photo Resistor Dark Resistance and its equation

Photo-Resistor Dark Resistance

When the cell of photo-resistor is kept in the darkness, the resistance is referred as dark resistance.

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