Patent ID: 8441649

Claim:
A multi-beam interferometer displacement measuring system utilized in a large measuring range comprising: a light source module having an emitter emitting a non-polarizing beam; and a polaroid sheet used to receive the non-polarizing beam emitted from the emitter and transforming the non-polarizing beam into a polarizing beam; a resonator module used to receive the polarizing beam of the light source module and having a coated glass panel mounted away from the polaroid sheet opposite the emitter to receive the polarizing beam of the light source module, used to reflect the polarizing beam back to the polaroid sheet and the polarizing beam transmitting through the coated glass panel; a corner cube prism movably facing the coated glass panel opposite the polaroid sheet, used to receive the polarizing beam of the light source module that is transmitted through the coated glass panel and reflects the polarizing beam back to the coated glass panel to form a resonant cavity between the coated glass panel and the corner cube prism and having multiple reflecting mirrors reflecting the polarizing beam of the light source module to divide the polarizing beam into multiple interferential stripes; and a wave-delay plate mounted between the coated glass panel and the corner cube prism and used to receive the polarizing beam of the light source module reflected from the corner cube prism; and a detecting device facing the coated glass panel of the resonator module opposite the corner cube prism, used to receive the interferential stripes formed in the resonator module and having a polarizing beam splitter facing the coated glass panel opposite the wave-delay plate, used to receive the interferential stripe formed in the resonator module and split the interferential stripe into two sub-beams; two power detectors mounted near the polarizing beam splitter, respectively used to receive and detect the sub-beams split by the polarizing beam splitter and respectively form signals corresponding to the sub-beams of the interferential stripe; and a signal processor electrically connected to the power detectors and used to calculate and analyze the signals corresponding to the sub-beams of the interferential stripe to measure the displacement of the corner cube prism.