In a medical apparatus, an ultrasound generator generates ultrasound waves to be radiated into the region, and an ultrasound radiating-direction changing member changes in the region a radiating direction of the ultrasound waves to be generated by the ultrasound generator. An ultrasound converging member converges in the region the ultrasound waves subjected to the change of the radiating direction. Light which is reachable to the region is emitted from a light source unit. A light transmitting/receiving member radiates light emitted from the light source unit and receives light reflected in a converged region of the ultrasound waves in the region. Based on the reflected light, information showing the internal state in a desired deeper region in the membrana mucosa of the body tissue of the object.