| 摘要 |
<p>Modulated light from a light source is incident on the surface of a scattering medium, and light passing through this scattering medium is externally detected. A signal of a predetermined frequency component is extracted from this detection signal to detect a photon density wave propagating in the scattering medium. A signal extracted to correspond to this photon density wave is compared with the signal of the predetermined frequency component constituting the original incident modulated light to detect a predetermined quantitatively measurable parameter such as a phase difference at a detection point. This parameter has a specific relationship with the absorption coefficient by an absorptive constituent in the scattering medium as being derived from the photon diffusion theory, so that the predetermined parameter is appropriately arithmetically processed to obtain various kinds of absorption information (including the linear integration value of the absorption coefficient in the scattering medium and the concentration of a specific material) associated with absorption in the scattering medium. <IMAGE></p> |
