Acoustic calibration apparatus for calibrating plethysmographic acoustic pressure sensors

US5448904A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• Allan J. Zuckerwar · Newport News, US
• David Davis · Darlington, GB

Key dates

• Filing date: May 11, 1994
• Grant date: Sep 12, 1995
• Expiry date: May 11, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G01H3/005
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An apparatus for calibrating an acoustic sensor. The apparatus includes a transmission material having an acoustic impedance approximately matching the acoustic impedance of the actual acoustic medium existing when the acoustic sensor is applied in actual in-service conditions. An elastic container holds the transmission material. A first sensor is coupled to the container at a first location on the container and a second sensor coupled to the container at a second location on the container, the second location being different from the first location. A sound producing device is coupled to the container and transmits acoustic signals inside the container.