Patent US 4,030,342

An acoustic microscope for scanning an object stereo-optically and with both dark field and light field imaging. The microscope focuses acoustic waves on a focal point and moves the object in a planar raster pattern through the focal point. The acoustic waves are modulated by the object and displayed on an oscilloscope. The microscope permits the rotation of the object about the focal point so that two, azimuthally displaced images of the object can be obtained. These two images can be observed as one three-dimensional image in a lenticular stereoscope. In addition, the microscope can scan the acoustic waves scattered by the object and display a dark field image of the object.