Two-dimensional UV compatible programmable spatial filter
US6686995B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2002 |
| Grant date | Feb 3, 2004 |
| Priority date | — |
| Expiry date | Jun 4, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/95623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed are mechanisms for selectively filtering spatial portions of light emanating from a sample under inspection within an optical system. In one embodiment, a programmable spatial filter (PSF) is constructed from materials that are compatible with light in a portion of the UV wavelength range. In a specific implementation, the PSF is constructed from a UV compatible material, such as a polymer stabilized liquid crystal material. In a further aspect, the PSF also includes a pair of plates that are formed from a UV grade glass. The PSF may also include a relatively thin first and second ITO layer that results in a sheet resistance between about 100 and about 300 &OHgr; per square. The PSF provides selective filtering in two directions. In other words, the PSF provides two dimensional filtering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.