Patent ID: 8152712

Claim:
An endoscope system including an electronic endoscope with a solid-state image sensor, a processor device for producing an image from an image signal from said solid-state image sensor and a light source device, said electronic endoscope including a light guide for transmitting light which illuminates an object when said solid-state image sensor captures said image of said object, said light guide having a bundle of optical fibers, said endoscope system comprising: a cap having a test chart, said cap being attached to a distal portion of said electronic endoscope so that said solid-state image sensor captures an image of said test chart to output a chart image signal; a photometric circuit for measuring an average luminance value of said test chart from said chart image signal; and a broken fiber number calculator for calculating the number “N” of broken optical fibers of said optical fibers that satisfies the following expression: N=M× (1− Y/I ) wherein, “Y” represents said average luminance value detected by said photometric circuit, “I” represents an ideal average luminance value when all of said optical fibers are conducting, and “M” represents the total number of said optical fibers.