Visual display of ultrasonic radiation pattern
US3969578A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1975 |
| Grant date | Jul 13, 1976 |
| Priority date | — |
| Expiry date | Mar 14, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N29/4454
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Detection of peak phase change at ultrasonic frequency in two mutually coherent interfering light components, one of which is obtained by reflection from a rigid reference mirror and the other of which is obtained by reflection from a spot of a flexible pellicle mirror which is insonified by an ultrasonic radiation pattern, will provide an output proportional to the displacement amplitude of vibration of the spot of the pellicle, if, as is the case, the round trip optical path to the rigid reference mirror is wiggled through an excursion greater than one-half the wavelength of the coherent light at a frequency which is much lower than the frequency of the ultrasonic radiation insonifying the pellicle and the displacement amplitude is very many times smaller than the light wavelength. By raster scanning the spot over the area of the pellicle in synchronism with the raster scanning of the electron beam of a C.R.T., and at the same time intensity modulating the electron beam of the C.R.T. in accordance with the peak detected output, a two-dimensional visual display of the radiation pattern insonifying the pellicle is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.