PROBLEM TO BE SOLVED: To establish more effective technique for inputting or recognizing subject identification information since there is a problem that the input work of the subject identification information by a measuring person in biological light measurement brings complication when biological information of multiple subjects is obtained, so as to increase difficulty in information management and also to generate the risk of an input mistake.SOLUTION: An optical attenuation and absorbance, obtained by a biological light measuring instrument are compared with one kind of or a plurality of kinds of previously preserved subject information, thereby the optimum subject identification information is selected and the selected identification information is displayed in a display means.
