Field-of-view frame switching device
US6181881A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 1, 1998 |
| Grant date | Jan 30, 2001 |
| Priority date | — |
| Expiry date | Dec 1, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B13/12
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A field-of-view frame switching device has a rectangular fixed field-of-view frame and a plurality of light-shielding members for covering portions of the rectangular fixed field-of-view frame so as to vary the size of the actual field-of-view frame. The light-shielding members are composed of a first pair of oppositely arranged light-shielding members and a second pair of oppositely arranged light-shielding members. The field-of-view frame switching device also has a coupling member for coupling the light-shielding members together in such relation that, when the first pair of light-shielding members are positioned closer to each other to narrow the actual field-of-view frame, the second pair of light-shielding members are positioned wide apart from each other and that, when the first pair of light-shielding members are positioned wide apart from each other, the second pair of light-shielding members are positioned closer to each other to narrow the actual field-of-view frame. The field-of-view frame switching device further has a moving member for moving at least a part of the light-shielding members in a direction substantially parallel to one side of the rectangular fixed field…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.