Acoustic wave generating apparatus
US5616865A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 22, 1995 |
| Grant date | Apr 1, 1997 |
| Priority date | — |
| Expiry date | Mar 22, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2632
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for non-destructively inspecting for faults in or beneath the surface of structures, such as debonds or delaminations in composite materials, or cracks, broken stringers, delaminations and the like in semi-monocoque structures, includes at least one spark gap discharge device displaced from the test object which focuses an acoustic pulse onto a small local area of the object for vibrationally exciting the surface of that area. A laser Doppler camera system, also displaced from the test object directs a laser beam onto the excited area and derives from light energy reflected back from the excited area the velocity of out-of-surface displacement of, and relaxation frequencies generated by, the surface of the excited area and provides an indication of whether a fault is present in that area. Acoustic pulses and the laser beam are directed to successive local areas in synchronism according to a scanning pattern, at each of which the reflected light energy is analyzed, following which the acquired data is processed and visually displayed in a manner which clearly indicates the presence of a fault and its location and enables the operator to further analyze the data to ascertai…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.