| 摘要 |
PURPOSE:To measure the driving current to light output of a laser diode in such a state that the heating value of the laser diode is small by applying a pulse current to the laser diode. CONSTITUTION:A current which varies stepwise is supplied to a switch 2 from a power source 1 and switches 2 and 3 are turned on and off under the control based upon the output of a pulse generator 1. Namely, the output of the generator 4 is applied to the switch 2 and when the switch 2 is turned on, the switch 3 is turned off, so the stepwise current reaches its crest value. When the output of the generator 4 turns off the switch 2 and turns on the switch 3, the output of the power source 1 is not applied to the laser diode 5 and the switch 3 short- circuits both ends of the diode 5. Thus, the output of the generator 4 is so controlled to synchronize with the step period of the power source 1. Then, the output of the switch 2 is applied to the diode 5, whose light emission output is photodetected by a photodiode 6, so that the driving current to light output of the diode 5 is measured. |
