Multi-interferometric displacement measurement system with alternative measurement mirrors

This device is a multi-interferometric displacement measurement system with two alternative measurement mirrors, i.e. planar mirror or corner cube reflector. The system includes a light source module, a sensor head module, an object module, a signal processing module and a display module. In the light source module, there are He-Ne laser, optical isolator, fiber and fiber coupler. Laser light emerges from the light source module and spreads into the sensor head module which consists of a fiber coupler, a beam splitter, a polarized beam splitter, a coated glass plate, a waveplate, two photodiodes and a pre-amplifier. From the measurement mirror the light beam is reflected back to the sensor head and then is transmitted to the signal processing module which has a secondary amplifier and a signal processing element connected with the sensor head module. The display module is linked to the signal processing module. According to arrangement of this apparatus, the proposed displacement measurement interferometer is