SELF-CALIBRATING CAPACITIVE CONVERTER Russian patent published in 1999 - IPC

FIELD: acoustic measurements. SUBSTANCE: invention is related to field of acoustic measurements and is based on contact-free methods of excitation and reception of ultrasonic vibrations. Self-calibrating capacitive converter is used with sample in the capacity of second electrode and has counter electrode and source of polarizing voltage for connection to counter electrode and sample. Converter is also fitted with unit exciting vibrations of counter electrode and unit extracting vibrations of counter electrode and generating controlling signal that is connected by feedback to source of constant polarizing voltage. EFFECT: increased accuracy of acoustic measurements thanks to exclusion of random and systematic components of errors caused by instability of sensitivity of capacitive converters. 2 dwg