The light source device has the same detection range as the first and second semiconductor light emitting elements, and first and second light amounts for detecting the light emission amounts of the first and second semiconductor light emitting elements, respectively. In order to match the first and second light amounts, which are the maximum usable light amounts of the detection unit and the first and second semiconductor light emitting elements, with a predetermined value within the detection range, the first light amount from the first semiconductor light emitting element. A first light amount limiting unit that limits the light amount of the first light incident on the detection unit and a second light source that restricts the light amount of the second light incident on the second light amount detection unit from the second semiconductor light emitting element. And controlling the light emission amounts of the first and second semiconductor light emitting elements based on the light quantity limiting means having at least one of the light quantity limiting units and the detection results of the first and second light quantity detection units. And a control unit.光源装置は、第１及び第２の半導体発光素子と、相互に同一の検出レンジを有し、第１及び第２の半導体発光素子の発光量をそれぞれ検出するための第１及び第２の光量検出部と、第１及び第２の半導体発光素子の使用最大光量である第１及び第２の光量を検出レンジ内の所定値に一致させるために、第１の半導体発光素子から第１の光量検出部に入射される第１の光の光量を制限する第１の光量制限部及び第２の半導体発光素子から第２の光量検出部に入射される第２の光の光量を制限する第２の光量制限部のうちの少なくとも一方を有する光量制限手段と、第１及び第２の光量検出部の検出結果に基づいて、第１の半導体発光素子及び第２の半導体発光素子の発光量を制御する制御部とを具備する。
