Thermal head drive circuit
US4536774A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1984 |
| Grant date | Aug 20, 1985 |
| Priority date | — |
| Expiry date | Mar 21, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D15/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
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 printing quality of a thermal head recording apparatus for printing successive lines. Improved printing 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 accumulation state operator for computing 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 either a pulse interval detector for detecting a time interval from a termination of printing of a previously printed line, or a temperature detector for detecting an internal-temperature of a thermal head. The pulse energy operator uses data from the heat accumulation state operator, from the memory which has data on the pulse energy used in previously printed lines, and from either the pulse interval detector or the temperature detector. The…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.