Modulation characteristics and stability of current modulated He-Ne lasers in case of excess excitation are investigated. Impedances of laser tubes under small signals are measured when the bore diameter, gas pressure and the capillary length are varied, and its equivalent circuit is obtained.
Dynamical characteristics of current and laser oscillation under large signals are measured. In case of on-off modulation, the laser oscillation builds up rapidly after a 2 AS delay against the discharge current and decays with a time constant of about 3, as at the maximum. Under typical operating conditions, on-off modulation up to 200 kHz is the practical upper limit. Rate-equation approach gives a qualitative description of the build-up of laser oscillation.
Drift and stability of characteristics of laser oscillation vs. current are discussed. Applica-tions to picture recording are also briefly noted.
抄録全体を表示