Cold shielding of infrared detectors
US4972085A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 1989 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Sep 14, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2005/065
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An infrared detection system is disclosed in which a re-imaging optical system produces a non-axisymmetric aperture stop image at an exit pupil point in or near the cold shield entrance aperture. To achieve high cold shield efficiency notwithstanding the asymmetry of the aperture stop image and the resulting astigmatism in such image, two exit pupil stop members disposed in non-coplanar relation are provided adjacent the exit pupil point. The stop aperture in one such member has its radially extending edges congruent with the corresponding edges of the aperture stop image and is disposed in the plane of best exit pupil formation for those edges; the aperture in the other exit pupil stop member is correspondingly configured and oriented with respect to the circumferential edges of the aperture stop image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.