Wide-angle polarization-independent narrow-band spectral filter and method

摘要: An optical arrangement ( 10 ) comprising a first beam splitter 12 for transmitting light of polarization, to provide beam, and reflect second polarization; spectral filter 16 in alignment with the being adapted return thereto; polarization rotator 14 effecting rotation relative whereby has is reflected by ). In specific implementation, may be Bragg grating, quarter-wave plate 22 ), Faraday 32 or other suitable device. If used, adjuster 34 used therewith. A number alternative embodiments are disclosed. embodiment, 44 disposed from third beam. one variant 48 another variant, 52 receive 68 between 64