Optical computed tomography imaging of absorbers hidden in scattering medium by detection of ultrasonic phase-shift caused by laser illumination-ultrasonic velocity imaging

To obtain an optical CT (Computed Tomography) image of a living body, we proposed a method for detecting local temperature variation caused by optical absorption as the variation of ultrasonic velocity in a tissue mimicking material. Through a basic experiment, we confirmed that it was possible to detect the variation of ultrasonic velocity as the phase difference of an ultrasonic wave propagating in a medium with the scattering coefficient equivalent to that of a living body.