Endoscope system

To acquire three high frame rate (temporal resolution) and high quality images of a normal image, a blood vessel highlighting image and an oxygen saturation image even in the case of acquiring the images by a frame sequential method. An endoscope system sequentially emits blue narrow-band light BN with a center wavelength of 415 nm, oxygen saturation measuring light with a center wavelength of 473 nm, G light and R light to a specimen, and sequentially images its reflection image. Through the imaging, the system can acquire blue narrow-band image data BN, measuring (oxygen saturation measuring) image data Bm, green image data G and red image data R. The system combines the blue narrow-band image data BN with the measuring image data Bm to obtain combined blue image data. The system generates a normal image on the basis of the combined blue image data, the green image data G and the red image data R. The system generates a first narrow-band image with a surface blood vessel highlighted, on the basis of the blu