- The optical transducer convert light into electrical quantity. They are also called as photoelectric transducers.
- The optical transducer can be classified as photo emissive, photoconductive and photovoltaic transducers.
- The photo emissive devices operate on the principle that radiation falling on a cathode causes electrons to be emitted from the cathode surface.
- The photoconductive devices operate on the principle that whenever a material is illuminated, its resistance changes.
- The photovoltaic cells generate an output voltage that is proportional to the radiation intensity.
- The radiation that is incident may be x-rays, gamma rays, ultraviolet, infrared or visible light.
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