Automatic image-density control system
US4812881A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1987 |
| Grant date | Mar 14, 1989 |
| Priority date | — |
| Expiry date | Jan 27, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/5025
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An automatic image-density control system for photo-copying the page-to-page content of an open book, in which optimum values (of exposure or development bias) needed for precisely copying the page-to-page content are initially established by performing either continuous pre-scanning of both pages of an open book or pre-scanning of the second page after completing photo-copying of the first page, and then, based on the optimum values thus established in conjunction with the first page content, photo-copying operation for the first page content is executed, and then, based on the optimum values established for the second-page content, photo-copying operation is sequentially executed for the second-page content.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.