Infrared holographic defect detector
US5041726A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1990 |
| Grant date | Aug 20, 1991 |
| Priority date | — |
| Expiry date | Jun 11, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2226/11
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An infrared holographic defect detector (10) comprises a far infrared pulsed coherent source (14) of infrared radiation which provides infrared radiation. The radiation is directed at a generally non-reflective surface (12), for example, a surface of an automobile body having a matt grey pre-coat thereon. A semi-transparent mirror (15) is placed in the path of the radiation to provide a reference beam (17) therefrom. An infrared detector (18) and a charge-coupled device (20) receives the radiation reflected from the surface and the reference signal. A comparator (22) compares the received reflected information and the reference signal and, preferably, information from a source (24) which defines a desired surface configuration in order to derive a quantitative measurement of the surface. A monitor (26) visually displays the quantitative mesurement and location of any dents in the surface. To avoid a requirement that sequential automobile doors containing the surface of investigation be three-dimensionally aligned to within microns of reference points, a detector of the reflected radiation can be translated and rotated. A number of sensed images of the surface are taken, one at each…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.