Automatic inspection of print quality using an elastic model
US6665424B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 1, 1999 |
| Grant date | Dec 16, 2003 |
| Priority date | — |
| Expiry date | Sep 1, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41F33/0036
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a process for producing by electronic means a model for automatically inspecting the print quality on deformable objects. The model is firstly produced by capturing with an electronic camera (CCD for example) the images of a set of sheets whose print quality is regarded as acceptable; the images are stored so as to produce a first reference image, together with the relevant densitometric tolerance limits. This reference image is thereafter divided into a multitude of sub-images by superimposing a grid with very small mesh cells. During inspection, the distances between the nodes of the grid are measured on the image to be inspected: this therefore produces an elastic modification of the model, which is such as to make the distances between the nodes the same as in the image to be inspected. The image to be inspected is thus verified with respect to the modified reference (model) by using any of the standard inspection techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.