| 摘要 |
PURPOSE:To make the extinction ratio of the laser diode constant and to perform the stabilization of the amplitutudes of a light output and a pulse output concurrently, by providing a light output control loop which is operated so as to make a photoelectric transducer output constant and a light control loop which is operated to make an average light output constant. CONSTITUTION:Even through temperature is fluctuated, the maximum light output and the minimum output are made not to be fluctuated (the extinction ratio is not fluctuated), and the average light output and the photoelectric transducer pulse output are not to be fluctuated. The light control circuit is composed of a photodiode PD, an amplifier circuit A, a high pass filter HPF, a detector DEF, a low pass filter LPF2, a comparing amplifier Ap, a constant current circuit CCp, and a high speed switching circuit SW. The pulse output is stabilized by said light control circuit. The other light control ciruit is composed of a photodiode PD, the amplifier circuit A, a low pass filter LPF1, a comparing amplifier circuit Ab, and a constant current circuit CCb. The average light output is stabilized by said light control circuit. |
