Design of a prism to compensate the angular-shift error of the Acousto-optic Tunable Filter

Abstract

The Acousto-Optic Tunable Filter (AOTF) is a high-speed full-field monochromator which generates two spectrally filtered light beams with ordinary and extraordinary polarization state. The angle of diffracted light in an AOTF changes according to the scanning of wavelength, which causes an image shift on a CCD plane. An analytic design of a prism system to compensate for the angular-shift error is proposed in this paper. Analysis of light paths in a prism and experimental results verify a proposed compensation method. Experimental results agreed with simulation results based on the suggested prism model. Angular-shift errors of ordinary and extraordinary rays are simultaneously minimized at optimal conditions with the designed prism. (C) 2008 Optical Society of America