| 摘要 |
PURPOSE:To stabilize a semiconductor laser light emitting quantity without increasing the weight and complicating the constitution by using a non-polarizing beam splitter to provide a reflecting surface. CONSTITUTION:After a light flux from a semiconductor laser 108 goes to a parallel light by a collimator lens 109 and the flux receives the amplitude division with a non-polarizing splitter 11, a transmitted light flux is diaphragmed as an optical spot onto an optical card 101 by an objective lens 111. After the light flux reflected by the card 101 is reflected, the flux arrives at the light receiving part of a sensor 28. The light flux reflected by other splitter 11 is reflected by a reflecting surface 17 of the splitter 11 again, passes through the splitter 11 again and arrives at the light receiving part of the sensor 28. The reflecting surface 17 is inclined, for that reason, the reflected light flux proceeds by the angle different from the light flux reflected by the card 101, and consequently, in the light receiving part of the sensor 28, converged to the positive different from the reflecting light from the card 101. Based on the output of the sensor 28, the light emitting quantity of the laser 108 is controlled. |
