Methods and apparatus for characterizing a surface
US5625451A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1995 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | Nov 27, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/474
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for characterizing a surface are disclosed. The system includes a light source and source optics which direct a beam of light toward the surface. A first optical integrating device is positioned and configured to receive a first portion of the scattered light which corresponds to a first range of spatial frequencies. A second optical integrating device is positioned and configured to receive a second portion of the scattered light corresponding to a second range of spatial frequencies. In one embodiment, an integrating sphere is employed as the first optical integrating device. The sphere includes a sampling aperture which is surrounded by a light absorption region on the interior of the sphere. Total integrated scatter data is generated for each range of spatial frequencies and is used to approximate the spectral scatter function of the surface. RMS roughness is then approximated for any range of spatial frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.