Electro-optical sensor

Electro-optical sensors are electronic detectors that convert light, or a change in light, into an electronic signal. These sensors are able to detect electromagnetic radiation from the infrared up to the ultraviolet wavelengths.^[1] They are used in many industrial and consumer applications, for example:

Function[edit]

An optical sensor converts light rays into electronic signals. It measures the physical quantity of light and then translates it into a form readable by an instrument. An optical sensor is generally part of a larger system that integrates a source of light, a measuring device, and the optical sensor. This is often connected to an electrical trigger. The trigger reacts to a change in the signal within the light sensor. An optical sensor can measure the changes from one or several light beams. When a change occurs, the light sensor operates as a photoelectric trigger and therefore either increases or decreases the electrical output. An optical switch enables signals in optical fibers or integrated optical circuits to be switched selectively between circuits. An optical switch can operate by mechanical means or by electro-optic effects, magneto-optic effects, and other methods.

convert a change of incident light into a change of resistance.

Photoconductive devices

commonly known as solar cells, convert an amount of incident light into an output voltage.

Photovoltaics

convert an amount of incident light into an output current.

Photodiodes

are a type of bipolar transistor where the base-collector junction is exposed to light. This results in the same behaviour of a photodiode, but with an internal gain.

Phototransistors

There are many different kinds of optical sensors, the most common types are:^[2]

Optical Switches are usually used in optical fibers, where the electro-optic effect is used to switch one circuit to another. These switches can be implemented with, for example, microelectromechanical systems or piezoelectric systems.