Testing of thermal imagers
US4861992A · kind A · utility
1Cited by
7References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1987 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Nov 12, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1313
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of testing thermal imagers includes heating selected portions of a quantity of a smectic liquid crystal material (9) with a laser (25) such that the material in the selected portions changes from a homeotropic texture in which it is transparent to incident infrared radiation to a focal conic texture in which it scatters incident infrared radiation. An infrared source (27) is arranged to direct infrared radiation onto the quantity (9) so as to read the pattern of selected portions across the quantity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.