Method for judging image quality using human-readable defect-sensitive patterns
US6598953B2 · kind B2 · utility
6Cited by
2References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 28, 2001 |
| Grant date | Jul 29, 2003 |
| Priority date | — |
| Expiry date | Dec 28, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65H2555/30
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method for monitoring the condition of an inkjet printhead. A test image is printed by the printhead and a second reference printhead. The density of ink dots in the test image is selected so that each dot just contacts adjacent dots while avoiding significant overlap. A defective nozzle can produce misplaced or undersized dots, creating abnormal spacing between adjacent dots. At the selected ink dot density, the abnormal spacing is most perceptible to the eye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.