PROCEDURE MEASURING ULTRASOUND VELOCITY IN CRYSTALS Russian patent published in 2002 - IPC

FIELD: measurement technology. SUBSTANCE: invention refers to measurement of ultrasound velocity in materials, specifically, in translucent dielectric and piezoelectric materials on superhigh frequencies. Ultrasound is excited in crystal by means of flat counterphase array of piezoconverters. Period of their arrangement is equal to d. Light beam is conveyed at double Bragg angle Θ_B from laser source on to one of faces of examined crystal and frequency f₀ of ultrasound excited by flat counterphase array of converters corresponding to condition of emergence of maximum of intensity of light beam twice diffracted by quadruple Bragg angle is recorded. Value of ultrasound velocity v is computed by measured frequency f₀ of ultrasound in agreement with expression where n is refractive index of crystal medium. EFFECT: simplified procedure measuring ultrasound velocity in crystals, enhanced accuracy of procedure. 2 dwg