Method and apparatus for sight reduction
US6038777A · kind A · utility
Inventor
Key dates
| Filing date | Jan 6, 1998 |
| Grant date | Mar 21, 2000 |
| Priority date | — |
| Expiry date | Jan 6, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C1/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sight reduction apparatus includes a sextant, a processor, and a nautical almanac, preferably all provided in an unitary housing. The sextant includes a fixed telescope which is pointed at a known celestial body, and a radial arm is moved against an arc graduated in degrees until a mirror mounted on the sextant reflects an image of the horizon down the telescope to coincide with the known celestial body. The angular elevation of the celestial body, corrected for the exact time and date, gives the position of the user on an imaginary circle. The nautical almanac provides essential data for determining the location of a predetermined list of celestial bodies relative to a fixed location. The processor is programmed to determine the position of a user based upon measurements made with respect to two celestial bodies using the sextant and information provided in the nautical almanac and to further provide the position of a user in terms of latitude and longitude. Preferably, the processor includes a memory having a matrix of data and equations which enable the processor to create a perpetual nautical almanac.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.