Broadband Beam Steering
نویسندگان
چکیده
A solid-state broadband beam deflector is described. This non-mechanical system steers spatially coherent broad band light to a common location in the far field. The components include a liquid crystal grating and achromatic Fourier transformer. The liquid crystal grating employs a polarization modulation scheme which produces a wavelength independent phase shift. The achromatic Fourier transformer eliminates grating dispersion. The modulation theory for the liquid crystal grating is introduced. Observations of the far field patterns for white light illumination of a binary liquid crystal grating and the design for the achromatic Fourier transformer are presented. Future research, including mid-infrared implementation is discussed.
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