Ring laser gyro bias drift improvement method and apparatus
US5438410A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1992 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Jun 18, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C19/665
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A ring laser gyro bias drift improvement method and apparatus for compensating for periodic bias drift including a microprocessor which controls a path length control circuit that continuously adjusts the position of path length control mirrors. The mirrors are stepped through a range of positions that represent two laser modes. The microprocessor adjusts the position of the two path length control mirrors such that total path length remains constant. The invention improves bias drift by forcing the laser gyro system to operate at varying path length control positions. Each position has a varying bias that was shown to be periodic over two laser modes. By operating the laser system over a range of two laser modes the periodic bias error of the laser gyro is cancelled out over time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.