sensor proximity inductive
The inductive proximity sensor is a high-tech device that senses whether or not something is within reach, but without needing to touch it. Based on the principle of electromagnetic induction, its main structures are a coil of wire, an oscillator circuit output and detection circuit. The main function is to sense the changes in the magnetic field when target materials approach or withdraw from it, and this will make over to state can be seen in a given example here. Technical features include adjustable sensitivity, rapid response speed, and compatibility with a variety of materials. Fields of application include manufacturing, automotive and consumer electronics for requirement to detect the position or number of things."