Printing of angled and curved lines using thermal dot matrix printer
US4783667A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1987 |
| Grant date | Nov 8, 1988 |
| Priority date | — |
| Expiry date | Jul 17, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K15/028
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus are described for enhancing the visual quality of dot matrix characters printed by means of thermal printing technologies, particularly in enhancing diagonal lines and blended radii of curvature. Two independent techniques can be combined or used in isolation to effect this print enhancement. The first, quarter dot step resolution, enables printed dots to be positioned at one quarter their previous step displacement distance. Memory must be expanded to handle increased dot position resolution. The second technique is element energy control, which enables each element in the printhead to emit different energy levels. The individual dot energy control translates into control of the printed dot shape and size, which when properly controlled, allows printing of diagonal lines and blended radii of curvature. This second technique further increases the required memory space by an additional factor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.