PROBLEM TO BE SOLVED: To provide a light source device suitable to accurately detect the light quantity of irradiation light through a long period.SOLUTION: The light source device comprises: a light source which emits irradiation light to irradiate a subject therewith light detection means which detects the light quantity of irradiation light and irradiation light control means that is disposed between the light source and the light detection means and is capable of switching whether or not to cause the irradiation light to be made incident to the light detection means.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】長期間にわたって照射光の光量を正確に検出するのに好適な光源装置を提供する。【解決手段】光源装置を、被写体に照射される照射光を射出する光源と、照射光の光量を検出する光検出手段と、光源と光検出手段との間に配置され、照射光を光検出手段に入射させるか否かを切り替え可能な照射光制御手段とから構成する。【選択図】図2
