Patent ID: 8233512

Claim:
A laser light source module having a semiconductor laser array obtained by arranging a plurality of semiconductor laser elements in an array pattern mounted thereon, comprising: a stem; a plurality of power feeding lead pins arranged in a standing manner on the stem; a heat sink made of a thermally conductive material mounted on the stem; a sub-mount substrate made of an insulative material mounted on the heat sink; a first lead frame made of an electrically conductive and thermally conductive material and having a linear expansion coefficient similar to the linear expansion coefficient of the semiconductor laser array, mounted on the sub-mount substrate, having the semiconductor laser array mounted thereon, composing a power feeding path of the semiconductor laser array, and electrically bonded to the power feeding lead pins; a second lead frame made of an electrically conductive and thermally conductive material arranged on the sub-mount substrate side by side with the first lead frame, composing the power feeding path of the semiconductor laser array, and electrically bonded to other power feeding lead pins; and a wire for electrically bonding the semiconductor laser array and the second lead frame, wherein a relationship among a plate thickness a of the first lead frame, a plate thickness b of the second lead frame, and a plate thickness c of the semiconductor laser array satisfies a<b<a+c.