Diaphragm adjusting arrangement in a photographic enlarging or copying apparatus having several lenses with an adjustable diaphragm
US4961087A · kind A · utility
7Cited by
2References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 29, 1989 |
| Grant date | Oct 2, 1990 |
| Priority date | — |
| Expiry date | Jun 29, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/40
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A diaphragm adjusting arrangement in an enlarging appartus having several lenses with an adjustable diaphragm includes a motor drive for the common adjustment of the diaphragms of all lenses and a device for detecting the adjusting path. By means of the comparison of the actual position of the diaphragms with a given desired position in a control circuit, a control signal is generated for the motor drive to move the diaphragms into the given position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.