External compass module for night vision devices
US5270545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1992 |
| Grant date | Dec 14, 1993 |
| Priority date | — |
| Expiry date | Nov 30, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF41G1/46
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An external compass module for use with a night vision device. The module includes an annular ring which is adapted to fit a portion of the night vision device which contains the objective lens. The module further includes an enclosure having an internal chamber. A compass sensor having an angular scale for indicating direction is positioned within the chamber. Optical elements are positioned adjacent to the scale which relay and collimate an image of the scale to a reflecting lens element. The reflecting lens element then reflects the scale image toward the objective lens which results in the superimposition of the scale image on a scene being viewed by the user.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.