Development of Optical Filters Based on Photorefractive Materials
نویسندگان
چکیده
hotorefractive optical filters meet many of the very stringent requirements of modern electro-optic systems. They provide a narrow passband and good throughput. However, difficulties arise when designing a filter to operate at wavelengths where the photorefractive material has low sensitivity. We have demonstrated initial success in overcoming the frequency dependence. This task was accomplished by using an optical configuration of high sensitivity in terms of wavelength, incident angle, and polarization to generate prespecified grating spacings. The grating spacings were designed to satisfy Bragg conditions for efficient operation of the filter (diffraction efficiency) even when using lower sensitivity wavelengths and alternative geometries of interest.
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