Print inspecting method and apparatus
US4561103A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 1983 |
| Grant date | Dec 24, 1985 |
| Priority date | — |
| Expiry date | Mar 22, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D7/12
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
This invention relates to a technique for inspecting picture patterns on prints which are being run in a rotary press or the like, and more particularly to a method in which reference data read out of a reference print is written in a memory, and inspection data read out of a print under inspection is compared with the reference data for every picture element for instance to determine whether or not the print is acceptable, and an apparatus for practicing the method. The specific feature of the invention resides in that (1) in reading the above-described data a print running speed or the position of a picture pattern in the direction of width is detected to rewrite the reference data, (2) in data comparison, the comparison level is optionally set up, and (3) the data comparison is carried out not only for every picture element, but also for the sum of picture elements over the entire picture pattern and for the sum of picture elements arranged linearly in the print running direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.