Global Patent Index - EP 0973149 A2

EP 0973149 A2 2000-01-19 - Ultrasonic transducers

Title (en)

Ultrasonic transducers

Title (de)

Ultraschallwandlern

Title (fr)

Transducteurs ultrasonores

Publication

EP 0973149 A2 (EN)

Application

EP 99305633 A

Priority

  • US 11627198 A
  • US 30020099 A

Abstract (en)

Sonic transducers utilize resonant cavities of varying depths to achieve wide operational bandwidth. The transducers (29) may include a conductive membrane (38) spaced apart from one or more backplate electrodes (32a,32b). In one approach, spacing is achieved using a dielectric spacer (34) having a series of depressions (36) arranged in a pattern, the depressions forming cavities each resonant at a predetermined frequency. In another approach, the conductive membrane (62) is piezoelectrically active, and the transducer is simultaneously driven in both piezoelectric and electrostatic modes. <IMAGE>

IPC 1-7

G10K 9/12; G01H 11/06

IPC 8 full level

H04R 17/10 (2006.01); B06B 1/02 (2006.01); B06B 1/06 (2006.01); H04R 17/00 (2006.01)

CPC

B06B 1/0688 (2013.01); B06B 1/0292 (2013.01); B06B 1/0614 (2013.01)

DCS

BE DE FR GB NL

DOCDB simple family

EP 0973149 A2 20000119; EP 0973149 A3 20001227; JP 2000050392 A 20000218; JP 4294798 B2 20090715