Acoustic imaging system
US5375470A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1991 |
| Grant date | Dec 27, 1994 |
| Priority date | — |
| Expiry date | Dec 20, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/346
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An acoustic imaging system includes pairs of variable gain amplifiers for deriving essentially pairs of signals from respective signals generated in respective ultrasonic vibrators and the pairs of signals are superimposed on each other in a time difference corresponding to a phase angle of .pi./2 in frequency of ultrasonic waves. Amplification factors of the variable gain amplifiers are controlled so that the desired phase shift of the superimposed signals is obtained to attain dynamic focusing. Another acoustic imaging system includes a switch circuit having a two stage matrix switches construction that performs matrix switch functions in a smaller number of switch elements. Still another acoustic imaging system includes constituents for the aforementioned phase control for fine adjustment of delay time, the aforementioned switch circuit for rough adjustment of delay time, and variable gain amplifiers that perform smooth switching of the delay time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.