Patent ID: 8827896

Claim:
An endoscope apparatus comprising: a light source apparatus that emits excitation light in a wavelength band including a first wavelength band for exciting a first fluorescent substance accumulated in a subject part inside a body cavity and a second wavelength band that is different from the first wavelength band; an image pickup section configured so as to pick up an image of first fluorescence emitted when the first fluorescent substance accumulated in the subject part is excited by light in the first wavelength band and an image of second fluorescence emitted when a second fluorescent substance provided on a treatment instrument via which treatment of the subject part is performed is excited by light in the second wavelength band, to generate a fluorescence image; an information storing section that stores shape information including information on a shape and size of the second fluorescent substance; and an operation section that performs an operation to calculate a scaling factor based on the shape information and a size of a draw region of the second fluorescence in the fluorescence image, and further performs an operation to estimate a size of a region in which the first fluorescence is generated, based on the calculated scaling factor and a size of a draw region of the first fluorescence in the fluorescence image.