Acousto-optic filters on potassium dihydrogen phosphate with optimal angle aperture and maximum beam deflection

Results of a theoretical analysis on tunable acousto-optic im- aging filters using potassium dihydrogen phosphate crystals are pre- sented. It is found that the maximum angular aperture of an imaging filter at the optical wavelength 0.3 m is equal to 3 deg. The diffraction effi- ciency in the examined instrument reaches 30% at moderate levels 2W of electric driving power. This performance may be obtained in a cell based on the 010 plane of acousto-optic interaction with the cut angle 18.8 deg evaluated relative to the 100 axis. The device uses a piezoelectric transducer with dimensions 2.71.1 cm 2 generating a slow shear elastic wave in the crystal. The spectral resolution of the filter is equal to 12 cm 1 ; the spatial resolution is characterized by 550800 resolvable pixels in an image processed by means of the filter with linear aperture 0.81.1 cm 2 . © 2008 Society of Photo-Optical Instrumentation