A two-channel measuring acoustic microscope

A continuous-wave acoustic Doppler microscope designed for measuring the an gular dependence of the ultrasonic reflectance from sample surfaces is desc ribed. The acoustic and electronic units of the microscope are equipped wit h an additional reference channel for the precise measurement of the scanni ng coordinate. This simplifies the instrument design and increases its robu stness relative to mechanical vibrations and alterations of the immersion l iquid properties. The design of a device with a 40 to 90 MHz operation freq uency and algorithms for digital signal processing are considered. The resu lts of the investigation of the acoustic reflectance function for titanium nitride films deposited on a steel surface are presented as an example.