| 摘要 |
PROBLEM TO BE SOLVED: To obtain a semiconductor laser control device which is easily integrated, lessened in power consumption, and enhanced in drive speed by a method, wherein a single bipolar transistor chip is made to comprise an integrated circuit composed of a pulse width modulation-intensity modulation signal generating section, an error- amplifying section, and a current drive section, and the current drive section is provided in a negative feedback loop. SOLUTION: A pulse width modulation-intensity modulation signal generating section 22 generates light emission command signals, an error amplification section 23 constitutes an optical-electrical negative feedback loop 3 together with a photodetector 2 to control the current of a semiconductor laser 1, so as to make the detected signals of the photodetector 2 equal to light emission command signals. Moreover, a current drive section 24 outputs a drive current, which is generated by the sum of or a difference between the control current of the optical-electrical negative feedback loop 3 and the operating current of the drive section 24, as a forward current to the semiconductor laser 1. An integrated circuit 20 contained in a single bipolar transistor chip is composed of the pulse width modulation-intensity modulation signal generating section 11, the error amplification section 23, and the current drive section 24, and the current drive section 24 is provided inside the optical-electrical negative feedback loop 3. |
