| 摘要 |
<p>THERMALLY COMPENSATED REFERENCE INTERFEROMETER AND METHOD A first birefringent material is positioned to receive an optical output from an optical source. A second birefringent material is positioned to receivethe signal transmitted through the first birefringent material. The birefringence of the first birefringent material is modulated to produce a modulation in the phase difference between two polarizations propagated between the birefringent materials. A detector forms an electrical signal indicative of the phase shift produced by the first and second birefringent materials between a pair of orthogonal polarizations in the optical signal received by the first birefringent material. This phase shift is opposite to phase shifts caused by changes in thesource wavelength. A feedback signal indicative of the base shift caused by thecrystals is fed back to the optical source to stabilize its frequency. The system produces a temperature-independent phase shift between the two polarizations by apparatus of proper selection of the lengths of the crystals in the optical path.</p> |
