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:
Nov. 11, 2003
Filed:
Jan. 07, 2002
Bjorn A. J. Angelsen, 7051 Trondheim, NO;
Tonni F. Johansen, 7018 Trondheim, NO;
Other;
Abstract
Ultrasound bulk wave transducers and bulk wave transducer arrays for wide band or multi frequency band operation, in which the bulk wave is radiated from a front surface and the transducer is mounted on a backing material with sufficiently high absorption that reflected waves in the backing material can be neglected. The transducer is formed of layers that include a high impedance section comprised of at least one piezoelectric layer covered with electrodes to form an electric port, and at least one additional elastic layer, with all of the layers of the high impedance section having substantially the same characteristic impedance to yield negligible reflection between the layers. The transducer further includes a load matching section comprised of a set of elastic layers for impedance matching between the high impedance section and the load material and, optionally, impedance matching layers between the high impedance section and the backing material for shaping the transducer frequency response. For multiband operation, the high impedance section includes multiple piezoelectric layers covered with electrodes to form multiple electric ports that can further be combined by electric parallel, anti-parallel, serial, or anti-serial galvanic coupling to form electric ports with selected frequency transfer functions. Each electric port may be separately transceiver-connected to obtain parallel, anti-parallel, serial or anti-serial port coupling for multi-band transmission, and extremely wide-band reception.