Ultrasonic shape detection device for determining bone shape and strength

A shape detection device 3 is disclosed comprising: a wave transmission module 5,7 for transmitting an ultrasonic wave from a transmission transducer to a target object 22; a wave reception module 6 for receiving with a plurality of reception transducers surface waves that are reflected on a front surface of the target object 22; an incoming direction detecting module 82a detecting an incoming direction of the reflected wave to each transducer group, using a time difference between reception timings of two reception transducers constituting each group, wherein each group comprises two reception transducers adjacent to each other; a propagation time detecting module 82b for detecting a propagation time of the surface wave that reaches each group using a received wave signal of the surface wave of at least one of the two reception transducers constituting each transducer group; a reflection point detecting module 82c for detecting a reflection point of the ultrasonic wave on the object surface based on the incoming direction and the propagation time of the surface wave detected for each group; and a shape deriving module 82d for deriving a shape of the object surface using the reflection points for a plurality of the transducer groups.