The present invention provides a semiconductor laser including a plurality
of light emission portions provided on the same substrate, each of which
is adapted to emit laser beams with a multi-mode. A part of the plurality
of light emission portions constitute a main light emission group, and the
rest of the plurality of light emission portions constitute a sub-light
emission group. A main electrode for supplying a current to the main light
emission group and a sub-electrode for supplying a current to the
sub-light emission group are separately provided. With this configuration,
it is possible to keep the entire quality of laser beams of the
semiconductor laser constant.
