ENDOSCOPE SYSTEM WITH AMPLIFICATION OF FLUORESCENT IMAGE

An endoscope system is provided with an endoscope unit which emits an excitation light to an object to be observed and receives a fluorescent light emitted by the object, a filtering optical element, which extracts a predetermined component of the fluorescent light received by the endoscope unit, an image capturing device, which receives an image formed by the predetermined component of the fluorescent light, an amplifier, which amplifies an output signal of the image capturing device, and a gain controller, which automatically controls a gain of the amplifier in accordance with the output signal of the image capturing element.