Iris drive mechanism
US5315889A · kind A · utility
2Cited by
9References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1992 |
| Grant date | May 31, 1994 |
| Priority date | — |
| Expiry date | Jun 18, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/18952
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An iris drive mechanism has two slidable diaphragms which are operatively connected with a motor through a lever arrangement which, for a given motor output shaft rotational speed moves the diaphragms slowly at their extreme positions wherein the aperture is small and large respectively, and more quickly at an intermediate stage. The slower movement when the aperture is small improves the F number resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.