Patent ID: 8797393

Claim:
An electronic endoscope system comprising: an emission section for emitting white broadband light and narrow band light to a tissue site in a body cavity, the tissue site including a blood vessel; an imaging section in which a blue pixel, a green pixel, and a red pixel are arranged, the broadband light being sensed by the three color pixels, and the narrow band light being sensed by only one or two of the three color pixels; a signal obtaining section for obtaining a mixed image signal during emission of the broadband light and the narrow band light, the mixed image signal including a first color signal which is outputted from the pixel having sensitivity to the narrow band light and has a sum of a brightness value of the broadband light and a brightness value of the narrow band light, and a second color signal which is outputted from the pixel not having sensitivity to the narrow band light and has only a brightness value of the broadband light; a correlation information storage for storing correlation information between a brightness value of the pixel having sensitivity to the narrow band light and a brightness value of the pixel not having sensitivity to the narrow band light when only the broadband light is emitted; and a signal separator configured to calculate a brightness value of the broadband light contained in the first color signal from a brightness value of the broadband light contained in the second color signal and the correlation information, and subtract the calculated brightness value from the first color signal to obtain a brightness value of the narrow band light contained in the first color signal.