Patent ID: 9521952
Filing Date: 2016-12-20
CPC Classification: A61B

Claim Text:
1. A subject information acquisition apparatus comprising: an acoustic wave detector configured to receive a first acoustic wave generated in response to irradiation of a subject with first light having a certain wavelength and convert the received first acoustic wave into a first electric signal and configured to receive a second acoustic wave generated in response to irradiation of the subject with second light having the certain wavelength whose irradiation condition and irradiation time point are different from that of the first light and convert the received second acoustic wave into a second electric signal; and a processor configured to acquire an optical absorption coefficient and an optical scattering coefficient of the subject by using the first electric signal and the second electric signal, configured to acquire a light intensity distribution of the first light in the subject based on the optical absorption coefficient and the optical scattering coefficient of the subject acquired by using the first electric signal and the second electric signal, and configured to acquire information of the subject related to an optical absorption coefficient distribution in the subject by using the first electrical signal and the light intensity distribution of the first light in the subject, wherein the irradiation condition is at least one of a direction of light irradiation, an illumination distribution on the surface of the subject, and a position of light irradiation on the surface of the subject, wherein the processor is configured to: acquire a first initial sound pressure distribution in the subject by using the first electrical signal, acquire a second initial sound pressure distribution in the subject by using the second electrical signal, set temporary values of the optical absorption coefficient and the optical scattering coefficient of the subject, acquire a first temporary light intensity distribution of the first light in the subject and a second temporary light intensity distribution of the second light in the subject by using the temporary values, acquire, as the optical absorption coefficient and the optical scattering coefficient of the subject, the temporary values when it satisfies the following equation (1), by an inverse iteration method using a first initial sound pressure value P acquire the information of the subject by using the first initial sound pressure distribution and the light intensity distribution of the first light.