aperture synthesis technique using the echo hologram in the storage 80 the image producing portion 100 is one embodiment of image producing means in accordance with the present invention the image is reconstructed based on the equivalent 2 dimensional aperture 203 see fig2 encompassed within the circular orbit obt of the ultrasonic probe 10 by means of the aperture synthesis technique the scanning orbit of the ultrasonic probe 10 is not limited to a circle but may be any closed orbit as desired in the latter case the equivalent 2 dimensional aperture is a surface encompassed within the closed orbit the image reconstruction according to the aperture synthesis technique is performed by the convolution of the hologram data and a predetermined kernel in operating the equation 1 omitting z or the depth gives orthography and omitting y or the height gives tomography fig2 illustrates the concept of orthography 205 and tomography 204 along with a 2 dimensional aperture 203 reconstructed or produced is the image which represents the region ranging from the tip surface of the ultrasonic probe 10 to the position beyond a distance 3 4 times the diameter of the circular orbit 205 i e which represents the portion not.