Photoswitches, Proximity Sensors, and Feedback Devices

Photoswitches, proximity sensors, and feedback devices are all used to detect objects or information. They are useful in industrial and manufacturing environments to sense product or personnel in the line of machinery or equipment. This module discusses the operation of the different types of each of these.

•Describe the purpose of a photoswitch and its general operating principles •Differentiate between the five basic types of photoswitches (retroreflective, thru-beam, polarized, diffuse, and convergent beam) •Match the three basic types of proximity sensors (inductive, capacitive, and ultrasonic) with their principles of operation •Describe the purpose of a proximity sensor •Explain the operation of three feedback devices (incremental encoders, absolute encoders, and Hall effect sensors) •Describe the purpose of a feedback device