| 摘要 |
PROBLEM TO BE SOLVED: To adjust the quantity of laser beams to the aimed quantity of beams at a high speed with a high resolution, without using a CPU of high performance and a D/A converter having high resolution. SOLUTION: A laser generator comprises a semiconductor laser (LD) 1021, a coarse adjusting section 123 feeding back laser beams output from the laser 1021 and computing a coarse adjusting output value, a fine adjustment section 124 computing a fine adjusting output value and the D/A converters 131 and 133 converting the coarse adjusting output value into coarse adjustment signals ML and CL. The laser generator further has D/A converters 132 and 134 converting the fine adjusted output value into fine adjustment signals MS and CS, an adder 141 attenuating the coarse adjustment signal ML and the fine adjustment signal MS at severally different amplification factor and adding the signals ML and MS, an adder 142 attenuating the coarse adjustment signal CL and the fine adjustment signal CS at the severally different amplification factor and adding the signals CL and CS and a drive-current generating section 11 generating the drive current of the laser 1021. COPYRIGHT: (C)2005,JPO&NCIPI
|
