Viewfinder optical system
US5982561A · kind A · utility
3Cited by
3References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1997 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Jan 16, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/0095
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A viewfinder optical system has a relay optical system and an eyepiece optical system. The relay optical system has a first, a second, and a third relay lens. The eyepiece optical system has a first and a second eyepiece lens. The first eyepiece lens, which is disposed closest to a secondary-image plane formed by the relay optical system has an aspherical surface on its secondary-image plane side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.