Fluorescent endoscope system enabling simultaneous achievement of normal light observation based on reflected light and fluorescence observation based on light with wavelengths in infrared spectrum

Abstract

A visible light spectrum and a fluorescent light spectrum are received by a variable gain solid state imaging device provided to an endoscope. The variable gain solid state imaging device can be said to lower amplification levels for easily observed visible light spectrum, and higher amplification levels for low intensity fluorescent light spectrum observation. By varying the gain of the imaging device with the different spectrums, an object observed with the endoscope is displayed with approximately similar brightness in each white spectrum. A controller coupled to endoscope system switches different light spectrum to irradiate the observed object, while controlling amplification of the image device. The endoscope provides enhanced image detail to improve diagnosis and treatment of observed abnormal objects.