Patent ID: 8334892

Claim:
An image obtainment method, comprising: imaging an observation target to obtain ordinary images of the observation target by illuminating the observation target with illumination light and by receiving, at an imaging device, reflection light reflected from the observation target; and generating spectral estimation image signals of a predetermined wavelength by performing a spectral image processing on image signals output from the imaging device, wherein spectral estimation image signals of a specific wavelength related to an agent administered to the observation target are generated, as spectral estimation image signals for obtaining luminance information, based on the image signals output from the imaging device, the agent comprising a medical-chemical compound, wherein luminance information about each of the spectral estimation image signals for obtaining luminance information that have been generated at a predetermined time interval is obtained and a rate of change in the luminance information is obtained, and wherein the specific wavelength related to the agent comprises one of an absorption wavelength of the agent and a florescence wavelength of the agent.