Thermal head drive circuit
US4524368A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1984 |
| Grant date | Jun 18, 1985 |
| Priority date | — |
| Expiry date | Mar 30, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/365
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thermal head drive circuit with the input connected to a source of printing data and the output connected to a thermal head including heater elements, so as to improve the picture quality of a thermal head recording apparatus for printing successive lines. Improved picture quality is effected by using data from previously printed lines to compute a corrected pulse energy for the line being printed. The circuit uses a heat storage state operator for operating the heat storage state of each of the heater elements constituting a thermal head, a pulse energy operator for computing a printing pulse energy to be applied to each of the heater elements, a memory for storing the electrical pulse energy used in the previously printed line, and a counter to count the number of dots on the line to be printed. The pulse energy operator uses data from the heat storage state operator, the counter, and from the memory which has data on the pulse energy used in previously printed lines. The output of the pulse energy operator is connected to a pulse generator which is used to drive the heater elements of a thermal head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.