Thermal printing apparatus and method
US4758966A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1986 |
| Grant date | Jul 19, 1988 |
| Priority date | — |
| Expiry date | May 5, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4015
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thermal printing apparatus and method are disclosed which allows a plurality of thermal print head elements to remain concurrently active, with each individual element being capable of remaining active for a time duration unique to itself and independent of burn times required by the remaining elements. This individual element burn time control is obtained by the high-speed loading and reloading of the thermal print head shift register, with the contents of the individual shift register cells being the controlling factor. Once the thermal print head element resistances have been dynamically measured, specific energies are derived for each element in the printhead by modulating the on time for each element, thus allowing grey scale printing and the like.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.