| 摘要 |
PURPOSE:To stabilize the intensity of laser light by inserting a polarizer, which has an inclination of the plane of polarization equal to that of a reference of a diffracted light, between an acoustooptic modulator and an optical detecting means. CONSTITUTION:When a diffracted laser light 5 is varied, this variance appears as a variance of its light quantity E and a variance of an inclination theta of the plane of polarization of the laser light 5. When this diffracted laser light 5 is made incident to a polarizer 13, the quantity of transmitted light becomes Ecostheta and is subjected to rectification and detection. The quantity of transmitted light is separated into a passing light 7 and a detecting light 8 as variances of light quantity by a beam splitter 6, and the detecting light 8 including the variation detects always the quantity of the diffracted laser light 5 and the inclination of the plane of polarization of this light 5 by a feedback circuit, which applies a high frequency signal to a transducer 3 through a photodetector 9, an amplifier 10, and a high frequency modulator 11, to control them. As the result, the difference phenomenon of diffraction of the incident laser light is eliminated. |
