Method of adjusting print uniformity
US6819352B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 2003 |
| Grant date | Nov 16, 2004 |
| Priority date | — |
| Expiry date | Feb 4, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4015
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of adjusting print uniformity in a xerographic device is provided. The method includes: a) printing a test pattern, b) transferring the printed test pattern to a scanner, c) scanning the printed test pattern and detecting line information, d) communicating the detected information to a computer, e) determining measurements from the detected line information, f) calculating the difference between the measurements and target values, and g) depending on the difference, adjusting a current supplied to an individual LED of an LED printbar associated with the measurement to reduce the difference. In one aspect, a test pattern line is associated with an individual LED. In another aspect, test pattern lines are associated with two adjacent LEDs and three adjacent LEDs. In yet another aspect, the test pattern includes dotted lines. In still another aspect, the invention includes a xerographic device with an LED printbar, a computer, and a scanner device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.