Method for increasing depth of scanning field of a scanning device
US6557762B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 2000 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Feb 9, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10801
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Before assembling a scanning module, the type of the scanning module is predetermined. When the scanning module is predetermined, the shape of MTF-DF curve is therefore fixed. The scanning module includes a glass plate, lens and an image generating means. During the assembly, the image generating means and the glass plate are mounted. A correction document is placed on the glass plate. The position of the lens is adjusted in order to reflect a point at the lowest point of the tolerant range of the depth of scanning field in the MTF-DF curve. The position of the lens is then fixed. An increased depth of scanning field in a scanning device is thusly obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.