| 摘要 |
A passive device which allows processing of signals impressed upon a light beam and arranged so that sensitivity is maximized and signal dropout, due to environmental effects such as temperature, do not occur. The passive homodyne demodulator includes a beam combiner, for combining the impressed light beam with a reference beam, beamsplitters, polarizing beamsplitters, and birefringent elements used as polarization shifters, so that ouputs are produced which are the sine and cosine of the phase change between the sensor and reference beams due to changes in the effective optical path length difference of the reference and sensor fibers due to the effect sensed. These signals are then electronically converted into an electrical output which linearly represents the phase of the signal originally impressed on the sensor fiber.
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