Light source device

A light source device comprising:

• a substrate including a support surface;
• a first submount including
• a first mounting surface facing the support surface, and
• a first upper surface located on a side opposite to the first mounting surface;
• one or more laser diodes located between the substrate and the first submount and including a p-side electrode surface and an n-side electrode surface located on a side opposite to the p-side electrode surface;
• a lateral wall portion disposed on the substrate, the lateral wall portion including a second upper surface and an inner wall surface, the inner wall surface defining a space in which the laser diode is housed;
• a heat dissipation member disposed on the first submount;
• and
• a metal member bonded to the heat dissipation member and the second upper surface and sealing the space, wherein
• a height from the support surface to the first upper surface is different from a height from the support surface to the second upper surface, and
• one of the p-side electrode surface or the n-side electrode surface is directly or indirectly bonded to the support surface and the other of the p-side electrode surface or the n-side electrode surface is bonded to the first mounting surface.