| Summary: | 碩士 === 國立彰化師範大學 === 機電工程學系 === 97 === In this thesis, we present a sensitivity-tunable total-internal-reflection (TIR) heterodyne interferometer by using a special-designed TIR apparatus that consists of parallelogram prism and a half-wave plate. When a light beam is incident on a parallelogram prism, the beam is totally reflected in the prism and then the output light passes through a half-wave plate. Finally, the beam enters an electric-optic modulator and an analyzer for modulation and interference. Since the phase difference between s- and p-polarizations of the interference signal is associated with the azimuth angle of the half-wave plates, the phase difference can be controlled by changing the angle, hence yielding the sensitivity-tunable result. The angular sensitivity of -15000~15000(deg/deg) and refractional sensitivity of -5000~5000(deg/RIU) should be achieved in the system. Our method has the merits of high sensitivity, tunable sensitivity, and a short TIR apparatus length.
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