Non-contact non-destructive latent image scanner
US5313265A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1992 |
| Grant date | May 17, 1994 |
| Priority date | — |
| Expiry date | Mar 2, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A latent image scanner 10 comprising a three-color laser-diode interferometer 11 having either thickness gauge optical geometry 12 or profiler optical geometry 12a is focused on a spot on a surface of a reference optic 14 having a latent image residue thereon. The interferometry thickness gauge 10 or profiler 10a measures and records the height and location of the spot. The scanner 10 is then focused on a new spot by moving an associated X-Y mechanical translator 13. A complete scan of the surface of the reference optic 14 results in a three dimensional data array correlating height profile to X-Y coordinates of the surface of the reference optic 14. The difference between the absolute height profile and the known height of the reference optic 14 represents the latent image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.