Abstract: A light source device includes a connector, a light source, a lever member, and a detector. The connector allows the light guide member to be detachably connected thereto. The light source emits light to be incident on the light guide member connected to the connector. The lever member is displaced depending on presence or absence of the connection of the light guide member to the connector. The detector detects the displacement of the lever member and outputs a detection result.

Abstract: An endoscope system includes: an insertion component which includes a base end and a tip end, and is inserted into a subject at least up to the tip end; a light source which emits first light and second light having a hue different from a hue of the first light a light sensor; and a controller, the insertion component includes: a first light guide member which emits the first light and the second light from the tip end as illumination light; and a second light guide member which guides reflected light of the illumination light emitted from the tip end, the light sensor receives the reflected light guided by the second light guide member, and the controller controls the light source based on the intensity of the reflected light received by the light sensor to stop emission of the at least one of the first light or the second light.