Abstract: A planar waveguide laser crystal assembly includes an optical bench and a laser crystal mount mounted on the optical bench. The laser crystal mount includes an upper housing having an interior horizontal surface and an exterior horizontal, a lower housing coupled to the upper housing and having an interior horizontal surface and an exterior horizontal surface, and a cavity defined between the interior horizontal surfaces of the upper and lower housings. A laser crystal is mounted in the cavity of the laser crystal mount. Each of the exterior horizontal surfaces of the upper and lower housings is oriented parallel to a length of the laser crystal. The laser crystal assembly further includes a heat dissipating structure thermally coupled to at least one of the exterior horizontal surfaces of the upper and lower housings to dissipate heat transferred from the laser crystal mount.