GENERATING METHOD OF OPTICAL PULSE TRAIN AND SEMICONDUCTOR PULSE LASER DEVICE

摘要

PURPOSE: To obtain desired passive mode locking, when an optical pulse train is generated by a semiconductor pulse laser device having a saturable absorption region and a gain region which consist of semiconductor waveguides of the same composition on a common substratum. ;CONSTITUTION: A semiconductor pulse laser device consists of a first gain region 15 and a second gain region 17 whose gain regions are mutually electrically isolated. The length of one gain region is set longer than the other. A current is injected in the gain region 17 which is short, with a current density to generate gain saturation. A current is injected in the gain region 15 which is long, with a current density which is so low that gain saturation is not generated and enough to compensate light loss in the gain region 15.;COPYRIGHT: (C)1996,JPO