Patent ID: 7847817

Claim:
An endoscope light source unit for making illumination light from a light source incident on an incident end face of a light guide connected thereto, said endoscope light source unit comprising: an aperture device having a plurality of aperture openings of different opening ratios, for selectively positioning one of said aperture openings between said incident end face and said light source; a driving device for moving said aperture device; an index detection device for detecting whether a specific one of said aperture openings of said aperture device is positioned between said incident end face and said light source; an aperture opening position detection device for detecting whether any one of said aperture openings lies between the incident end face and the light source; a measuring device for measuring a driving amount of said driving device with respect to a position of said specific one of said aperture openings; and a controller for driving said driving device based on measurements from said index detection device, said aperture position detection device, and said measuring device.