近程传感器
The proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. It often emits an electromagnetic or electrostatic field, or a beam of electromagnetic radiation (infrared, for instance), and looks for changes in the field or return signal. The object being sensed is often referred to as the proximity sensors target. Different proximity sensor targets demand different sensors.
The proximity sensor can be used in parktronic, car bumpers that sense distance to nearby cars for parking, ground proximity warning system for aviation safety, and vibration measurements of rotating shafts in machinery