Intra-optical light beam sighting system for an infrared thermometer
US4494881A · kind A · utility
Inventor
Key dates
| Filing date | Mar 10, 1982 |
| Grant date | Jan 22, 1985 |
| Priority date | — |
| Expiry date | Mar 10, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/0896
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sighting system primarily for use with infrared thermometers and that provides a visible light beam, the geometry of which is congruent with the field of view of the infrared optics of the thermometer to provide the user with an accurate representation of the intersection of the field of view cross-section of the object of which the temperature is being measured by the thermometer. Two novel embodiments are disclosed, one of which utilizes Fresnel lenses and one of which utilizes a Cassegrainian lens system. Both embodiments provide means for accommodating an isolated visible light source and passage of the visible light generated therefrom through the identical lens system used by the infrared detector to develop the signal indicative of the infrared energy and therefore temperature generated by the object to which the infrared thermometer is directed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.