Exposure control process and photographic copying apparatus
US5164765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1991 |
| Grant date | Nov 17, 1992 |
| Priority date | — |
| Expiry date | Aug 16, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/72
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The copying light of a source of copying light is attenuated in areas using a mask with different density ranges to influence the density by areas of a copy to be produced from a copy master. The appropriate area of the mask is selected by analyzing a location dependent density variation of the mask stored in matrix form in a computing and evaluating unit by predetermined criteria. A photographic copying apparatus associated with the process includes an exposure station with a mask mounted on a slide. The slide may be displaced in response to control signals determined and generated in the computing and evaluating unit. The slide is displaced in a plane parallel to a transport plane of the copy master in the beam path of a source of copying light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.