Electroacoustic imaging methods and apparatus
AssigneeThe United States of America as represented by the Department of Health and Human Services
InventorsHan Wen, Robert S. Balaban
Life of this patent
Estimating the term…
Abstract
Methods are disclosed for obtaining electroacoustic images of specimens. One method includes applying an acoustic wave to a specimen and forming an image based on an electroacoustically induced electric field or voltage. In another method, an electric field or voltage is applied to a specimen and an electroacoustically induced acoustic wave is measured to form an image. Apparatus suitable for obtaining electroacoustc images are disclosed as well as methods for distinguishing image contributions from the electroacoustic, thermoacoustic, and Hall effects.
Claims23
A method for producing an electroacoustic image of a specimen, comprising:
- applying an electroacoustic probe signal to the specimen in the substantial absence of a magnetic field;
- detecting an induced signal that is a function of an electroacoustic parameter of the specimen;
- and
- generating an image based on the detected induced signal.
A method for obtaining an image of a specimen, comprising:
- applying a first magnetic field in a first direction to a specimen;
- obtaining a first image of the specimen, the first image including electroacoustic and Hall effect contributions;
- applying a second magnetic field to the specimen the second magnetic field in a direction opposite the first direction;
- obtaining a second image of the specimen, the second image including electroacoustic and Hall effect contributions;
- and
- obtaining an electroacoustic image by combining the first and second images to substantially eliminate the Hall effect contribution.
A method for obtaining an electroacoustic image of a specimen in the substantial absence of a magnetic field, comprising:
- applying a first voltage to the specimen to obtain a first image, the first voltage having a first polarity;
- applying a second voltage to the specimen to obtain a second image, the second voltage having a second polarity opposite the first polarity;
- and
- combining the first image and the second image to obtain a purely electroacoustic image.
An apparatus for electroacoustic imaging of a specimen, comprising:
- an acoustic transducer that produces an acoustic wave in the specimen, the acoustic wave electroacoustically generating an electric field;
- electrodes that generate a voltage in response to the electric field;
- and
- an image processor that receives the voltage from the electrodes and produces an image of the specimen.
An apparatus for forward or reverse electroacoustic imaging of a specimen, comprising:
- an acoustic transducer situated to transmit an acoustic wave to the specimen or to receive an acoustic wave from the specimen;
- two or more electrodes situated to apply a voltage to the specimen or to detect a voltage produced by the acoustic wave transmitted by the acoustic transducer;
- and
- an image processor that receives an electroacoustically generated voltage from the electrodes or an electroacoustically generated acoustic wave from the acoustic transducer and forms an image of the specimen.
Dependencies are inferred from the claim text.