Devices for probing by ultrasonic radiation
US4117446A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 20, 1977 |
| Grant date | Sep 26, 1978 |
| Priority date | — |
| Expiry date | Jun 20, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/345
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
N elementary transducers are distributed regularly along a line of scanni An ultrasonic frequency receiver is associated with phase lag means. The distribution over n successive elementary transducers of the phases corresponding to focusing at a predetermined distance or several successive distances from the line is stored. That distribution corresponds to several Fresnel zones. Switches first connect a generator to a group of n' transducers corresponding to the central Fresnel zone of said stored distribution and later connect a group of n transducers to the receiver direct and via the phase lag means according to the stored distribution(s). The groups of n' and n elementary transducers are shifted along the line at intervals of time. The phase lag means may consist of inverter means causing a phase angle of .pi..
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.