LIGHT EMITTING DEVICE, AND BASE

To provide a light emitting device that is excellent in heat dissipation properties.SOLUTION: A light emitting device comprises: a semiconductor laser element; and a base in which a bottom part including metal as a chief material and a frame part including ceramics as a chief material are joined to each other. The base has an arrangement surface on which the semiconductor laser element is arranged, a frame that surrounds the periphery of the arranged semiconductor laser element, and first and second electrode layers for electrically connecting the semiconductor laser element. The bottom part has the arrangement surface. The frame part has a joint surface that is joined to the arrangement surface, an inside surface that intersects the joint surface and forms a frame larger than the arrangement surface, and an inside surface that intersects the joint surface and forms a frame smaller than the arrangement surface. The second electrode layer is provided on a plane that intersects at least part of the inside surface of the frame part forming the frame smaller than the arrangement surface, and that is different from the joint surface.SELECTED DRAWING: Figure 3 【課題】 放熱性に優れた発光装置を提供する。【解決手段】 発光装置は、半導体レーザ素子と、金属を主材料とする底部と、セラミックを主材料とする枠部と、が接合された基部と、を備え、基部は、半導体レーザ素子が配される配置面と、配された半導体レーザ素子の周りを囲う枠と、半導体レーザ素子を電気的に接続するための第１及び第２電極層と、を有し、底部は、配置面を有し、枠部は、配置面と接合する接合面と、接合面と交わり配置面よりも大きい枠を形成する内側面と、接合面と交わり配置面よりも小さい枠を形成する内側面と、を有し、第２電極層は、枠部において、配置面よりも小さい枠を形成する内側面の少なくとも一部と交わる平面であって、接合面とは異なる平面上に設けられる。【選択図】 図３