Patent ID: 9198580
Filing Date: 2015-12-01
Classification: A61B,G01N

Abstract:
1. A constituent concentration measuring apparatus comprising: light generating means for generating light; light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means for generating light; light outgoing means for outputting the intensity modulated light toward a test subject, the intensity modulated light being intensity-modulated by the light modulation means for electrically intensity-modulating the light; acoustic wave detection means for detecting an acoustic wave which is emitted from said test subject irradiated with said intensity modulated light; and a container in which a space between said light outgoing means for outputting the intensity modulated light and said acoustic wave detection means for detecting the acoustic wave is filled with an acoustic matching substance having acoustic impedance equal to that of said test subject, wherein said light generating means for generating light generates two light beams having different wavelengths, said light modulation means intensity-modulates said two light beams so that the light beams have the same frequency and reverse phases, where one of the light beams is phase shifted by 180° from another of the light beams, and then multiplexes the light beams to generate one intensity modulated light beam in which the wavelengths of the two light beams appear alternately at a constant frequency, and a cross-sectional shape of said container is a semicircle, and said light outgoing means for outputting the intensity modulated light is positioned at the center of said semicircle.