Browse Prior Art Database

Transducer Array for Generation of Multiple Surface Wave Columns

IP.com Disclosure Number: IPCOM000077132D
Original Publication Date: 1972-Jun-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Heidrich, PF: AUTHOR [+3]

Abstract

A technique is described for generating high-density multiple line acoustic-surface wave (ASW) patterns where selection of individual ASW columns is desired.

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Transducer Array for Generation of Multiple Surface Wave Columns

A technique is described for generating high-density multiple line acoustic- surface wave (ASW) patterns where selection of individual ASW columns is desired.

Generally, to generate multiple columns of ASW, individual transducers are placed side-by-side. Some of the problems encountered are signal input connections to each of the transducers, multiple signal generators, or a way of switching the "if" signal to the required transducer, and packaging.

An array of transducers of proper design may be used to overcome the aforementioned problems. Design considerations for the array should include, center frequency, bandwidth, and aperture of individual elements. A particular array may consist of element 10 of Fig. 1 which would have a center frequency of 200 MHZ, and a zero-to-zero bandwidth of 5 MHZ; element 20 would have a center frequency of 202.5 MHZ and a bandwidth of 5 MHZ, additional elements would have the same frequency separation and bandwidth as shown in Fig. 1.

To generate an ASW from element 20, the proper frequency is selected. The only power consuming element is 20, and the remaining elements 30 are operating in a nonresonant mode with only capacitive reactance.

When matched to the generator by a wide-band impedance matching network, maximum energy is transferred to the resonant element and the losses due to the capacitive reactance of the nonresonant element are small for common piezoelec...