Photoconductor

Definition

A photoconductor is a material that becomes electrically conductive when exposed to light. It is used in various applications where controlling electrical conductivity through light exposure is required.

5 Must Know Facts For Your Next Test

1. A photoconductor has low electrical conductivity in the dark and high conductivity when illuminated.
2. The change in conductivity occurs because photons excite electrons, allowing them to move more freely.
3. Common materials used as photoconductors include selenium, cadmium sulfide, and lead sulfide.
4. Photoconductors are utilized in devices such as photocopiers and solar cells.
5. The efficiency of a photoconductor depends on factors like the wavelength of light and the material's properties.

Review Questions

• What happens to the electrical conductivity of a photoconductor when it is exposed to light?
• Name at least two common materials that are used as photoconductors.
• In what kind of devices might you find photoconductors being used?

Related terms

Photovoltaic Cell: A device that converts light into electrical energy by generating voltage from absorbed photons.

Photoresistor: A resistor whose resistance decreases with increasing incident light intensity.

Electron Excitation: The process by which an electron gains energy from a photon and moves to a higher energy state.