MULTISPOT ACOUSTOOPTIC MODULATOR

PURPOSE:To prevent a change of direction caused by the generation of heat with a reduction of the sound input and at the same time to show the perfect erasion of light to the zero sound input, by applying the doubling effect of repetitive interferences to the sound optical effect and cutting the zero order diffraction component. CONSTITUTION:An He-Cd laser 1 supplies the parallel beams to a diffraction cell 3. The cell 3 is formed by coating the dielectric multilayer films 3b and 3c on the surface of a tellurium glass plate having a parallel plane. A piezoelectric transducer 3d is attached to a acoustooptic solid material plate 3a, and the plane longitudinal wave is radiated by the function of the high frequency voltage given from a high frequency oscillator 4a. The light beam receives the Raman nasse diffraction. The zero order component is formed into an image through a lens 5a and erased at a trap 5c. All other diffraction components pass through a lens 5b and forms an image of the part where the light is irradiated to the cell 3 on a tentative image surface 5d.