Optical-hybrid etalons for simultaneous phase- and polarization-diversity operations
Patent 5903393 Issued on May 11, 1999. Estimated Expiration Date: 
December 4, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 4, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesDiffraction limited dichroic combiner diode laser Method and apparatus for ultra high frequency spectrum analysis Optical hybrid for coherent detection systems Beam splitter including a diffraction grating and one of step shaped, inclined, or curved transparent surface Polarization independent coherent lightwave detection arrangement Bulk optic wavelength division multiplexer Patent #: 5119454 InventorApplicationNo. 985108 filed on 12/04/1997US Classes:359/618, SINGLE CHANNEL SIMULTANEOUSLY TO OR FROM PLURAL CHANNELS (E.G., LIGHT DIVIDING, COMBINING, OR PLURAL IMAGE FORMING, ETC.)359/629, By partial reflection at beam splitting or combining surface372/92, PARTICULAR RESONANT CAVITY385/49, Fiber to thin film devices398/1, FAULT RECOVERY398/205Including polarizationExaminersPrimary: Ben, LohaInternational ClassG02B 27//10AbstractSimultaneaous phase- and polarization-diversity in a coherent receiver are provided from a single-unit 90°-hybrid (as shown in the upper section of FIG. 2) by combining the polarization angle and the phase angle of the input lightwave signal into an effective phase angle in the hybrid output. Thus, the number of components in the receiver is reduced as compared to conventional systems, thereby simplifying the processing network operations in the coherent detection system. The hybrid is implemented by the use of a quarter-waveplate (QWP)/etalon 30 in conjunction with an input QWP 32. The linearly polarized signal beam transmitting through the QWP 32 (of variable polarization angle) is incident to the 2-face 14 of the QWP/etalon 30. The linearly-polarized local-oscillator beam 18 is incident on the 1-face 12, and is aligned co-directionally to the reflected beamlets 20 of the signal beam 28. The proper orientation of the waveplates 30 and 32 and the proper selection of the etalon phase angle are key elements in providing simultaneous phase- and polarization-diversity in the single-unit 90°-hybrid. A detector processing network module converts the four output beams P1, 1/2P2, 1/2P2x, and 1/2P2y into balanced electrical signals and combines the signals into quadrature outputs that are squared and summed, thereby producing an electrical output signal that is independent of both phase and polarization fluctuations of the input signal beam 16.Other References
Field of SearchSINGLE CHANNEL SIMULTANEOUSLY TO OR FROM PLURAL CHANNELS (E.G., LIGHT DIVIDING, COMBINING, OR PLURAL IMAGE FORMING, ETC.)By partial reflection at beam splitting or combining surface By refraction at beam splitting or combining surface Including prismatic element OPTICAL FREQUENCY CONVERTER Etalon structure For diffractive subtractive filtering PARTICULAR RESONANT CAVITY Specified cavity component Reflector Fiber to thin film devices | |
