| 摘要 |
PURPOSE:To expand the utilization of a stable laser beam which has small difference in light intensity by reducing reflection loss, improving diffraction efficiency, and converging plural laser beams after ultrasonic wave modulation vertically or horizontally. CONSTITUTION:Picture signals S1-S5 from a signal source 1 and carrier frequencies f1-f5 from high frequency oscillators 21-25 are applied to amplitude modulator mixers 31-35. The frequencies f1-f5 which are amplitude-modulated and amplified through wide band amplifiers 41-45 are applied to respective transducers 61-65 of acoustooptic modulators 91-95. Then, the beam from a laser oscillator 10 is split into beams 151-155 through a parallel plane beam splitter 14, and they propagate in acoustooptic media 71-75 and enter an ultrasonic wave surface from transducers 61-65 at a constant Bragg angle. Ultrasonic wave signals propagates in the media 71-75, and optical modulation is performed by the mutual operation between their compressional waves and the laser beam; and 0-order light beams 121-125 and 1-order diffracted light beams 131-135 are projected from projection surfaces of modulators 91-95, and the reflection loss is reduced to prevent a decrease in diffraction efficiency. |
