Output controller of laser printer

Abstract

Abstract PURPOSE: To eneble to prevent a laser output from fluctuating by controlling an information signal to be supplied to a laser driver on the basis of the variation in the peak value of the laser output. CONSTITUTION: Gate signal (c) is supplied to gate circuit 12 to supply the output of photodetector 3 to peak holding circuit 13. Peak holding circuit 13 holds and supplies peak value (a) of the output of photodetector 3 to information signal amplifier 11, whose gain is controlled. Gate circuit 14, once supplied with gate signal (b), supplies the output of comparator 5 to laser driver 1 to set and control a direct current to be supplied to semiconductor laser 2. Thus, the magnitude of the information signal to be supplied to laser driver 1 is controlled on the basis of the peak value variation of the laser output to stabilize the laser output. Consequently, even if characteristics fluctuate or vary with elements owing to the secular change of the laser element, the invariably constant laser output can be obtained. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Isamu Shibata

Bibliographic Details