Method for testing and analyzing surface acoustic wave interdigital transducers
US4355278A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 1980 |
| Grant date | Oct 19, 1982 |
| Priority date | — |
| Expiry date | Aug 6, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/308
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Nondestructive testing and analyzing of surface acoustic wave (SAW) interdigital transducers is accomplished by observing electro-optic changes in a layer of liquid crystals produced by the effects of electric fields resulting from an electrical potential applied to the transducer. A display cell comprising a liquid crystal layer covered with a gold coated glass coverplate is fabricated on the surface of the SAW substrate under test. The assembled display cell is positioned for viewing under a microscope equipped for vertical illumination by a light source and a beam splitter. Polarizers are positioned in the illumination and viewing paths. An electrical potential is applied to the SAW device transducers and in some instances to the coverplate gold coat. Electro-optic effects produced in the liquid crystal by the electric field effects of the applied electrical potential are viewed through the microscope and are analyzed and interpreted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.