Surface characteristic determining apparatus
US9448057B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 2010 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Jul 12, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/65
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A wavelength selector (5) selects a wavelength of a broadband light source (4). A light director (BS1, BS2) directs light from the wavelength selector along a measurement path towards a region of a sample surface and along a reference path towards a reference surface, such that light reflected by the region of the sample surface and light reflected by the reference surface interfere to produce an interferogram. A controller (20) controls the wavelength selector to change the wavelength selected by the wavelength selector. A recorder (63) records successive images, each image representing the interferogram produced by a respective one of the wavelengths selected by the wavelength selector. A data processor (18, 180) processes the recorded images to produce at least one of a surface profile and a surface height map of at least a part of the sample surface. The reference path may be controlled to compensate for environmental effects such as vibration, thermal effects and air turbulence. The data processor may use a graphics processing unit to enable pixel data to be processed in parallel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.