The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 09, 1979
Filed:
Oct. 31, 1977
Bruce A Herman, Rockville, MD (US);
Harold F Stewart, Rockville, MD (US);
Abstract
A system and technique for determining the total radiated ultrasonic power output from a diagnostic ultrasound device having an output transducer includes a water chamber having a parabolic reflector. The transducer is mounted on the chamber at a location so that acoustic power from the transducer is focussed by the parabolic reflector to a first thermistor chip mounted in the chamber on a sound-absorbing rubber plate. The rise in temperature of the thermistor chip due to sound absorption changes its resistance. The thermistor chip is connected in one leg of a Wheatstone bridge. A reference thermistor chip is mounted on the rubber plate away from the ultrasonic beam and is connected in an opposite leg of the bridge. Starting from a null setting of the bridge, the output of the bridge after a suitable 'response time' is in accordance with the acoustic energy delivered by the transducer.