Compass
US5216816A · kind A · utility
11Cited by
12References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 8, 1991 |
| Grant date | Jun 8, 1993 |
| Priority date | — |
| Expiry date | Mar 8, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G9/0076
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a compass, the direction of the geomagnetism is detected by magnetic sensors and an azimuth detector, and data on the direction of the geomagnetism is supplied to a controller. A ROM stores declination data representing the angle formed between the direction of the geomagnetism and the direction of the geographic meridian. The data on the direction of the geomagnetism is corrected in accordance with the declination data stored in the ROM, to thereby obtain geographical direction data. This geographical direction data is displayed on a display device. In this manner, the compass enables the user to easily know a true direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.