Process and apparatus for the evaluation of the printing quality of a printed product by an offset printing machine
US4665496A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 29, 1984 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Oct 29, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41F33/0036
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Printed products and their respective corresponding printing plates are divided into a plurality of image elements. For each image element the surface coverage is determined by photoelectric measurements; a reference reflectance value is then calculated from these measurements, taking into consideration such parameters as the printing characteristic. These reference reflectance values are compared with the actual reflectance values measured on the printed products and the results of the comparison are evaluated to form a quality measure and to calculate control values for the ink feed devices of the printing machine. In this manner, the use of special color measuring strips may be eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.