Patent ID: 8681332

Claim:
A method of measuring a diffusion characteristic value of a light-emitting particle dispersed and moving at random in a sample solution using an optical system of a confocal microscope or a multiphoton microscope comprising steps of: moving periodically along a predetermined route a position of a light detection region of the optical system in the sample solution by changing an optical path of the optical system; measuring light intensity from the light detection region with moving the position of the light detection region in the sample solution to generate light intensity data; individually detecting a signal indicating light of a light-emitting particle on the light intensity data; extracting two or more signals corresponding to a same light-emitting particle among the detected signals indicating light of the light-emitting particle; and computing, using a computer, a diffusion characteristic value of the light-emitting particle corresponding to the extracted signals based on a deviation time from a moving cycle time of the light detection region in an interval of generation times of the extracted signals.