Endoscope system

Observation using a plurality of types of light having different spectrum characteristics is enabled while reducing the diameter of an insertion section of an endoscope, acquisition of a plurality of types of image which is applied with arithmetic processing with respect to each other and is displayed in a superimposed manner, so that the observation accuracy is improved. There is provided an endoscope system that acquires images of an object to be observed in a body cavity of a living body by being introduced at least partly into the body cavity including: a light source that emits a plurality of types of irradiation light having different spectral characteristics and being radiated onto the object to be observed; an optical system that propagates the irradiation light from the light source toward the object to be observed; an image pickup device which is provided at a portion to be inserted into the body cavity and is capable of picking up images of fluorescent light in a plurality of wavelength bands radiated from the object to be observed and light different in wavelength band from the fluorescent light by irradiating the plurality of types of irradiation light; a variable spectroscopic device which is arranged in an optical path between the image pickup device and the distal end of the portion to be inserted into the body cavity and is capable of changing the wavelength band of light entering the image pickup device from the object to be observed by varying the spectral characteristics thereof; and a controller that controls the light source, the variable spectroscopic device, and the image pickup device so as to acquire an image of the fluorescent light in a plurality of the wavelength bands and of the light different in wavelength band from the fluorescent light at the same position in a time-sharing manner.