Novel optical-electric sensor for displacement detection

A new method of detecting displacement by using a time interval is presented. A novel optical-electric sensor based on this method for displacement detecting was designed. In the mechanical structure of the sensor, the non-clearance mechanical joint and mechanical amplifying device are used to amplify the displacement accuracy. An optical-electric transition system is designed. There are two photoswitches in the system one is fixed, the other is movable. The change of the latter position acts on the change of displacement. By detecting a high frequency and constant pulse signal, the photoswitches transfers the position signal into time signal. With suitable transferring circuit, the system makes the certain displacement corresponding to the certain digital display. As a result, it realizes the displacement detecting. The sensor has high resolution and high stability. It is with a simple structure and a low cost and very suitable for long-period displacement condition monitoring.