Thermal printer and printing method thereof
AssigneeSamsung Electronics Co., Ltd.
InventorSang-sin Park
Life of this patent
Estimating the term…
Abstract
A thermal printer includes a dot number computing memory for detecting the number of dots which are simultaneously heated according to gradation by receiving image dam in line units, a dot number computing controller, a thermistor for detecting the temperature of a thermal print head (TPH), and a corrector for controlling the TPH to emit heat by gradation with a constant energy by varying the pulse width of a strobe signal depending on the detected number of simultaneous heated-by-gradation dots and temperature of the thermal print head, and the printing method thereof.
Claims20
A system for compensating for common drop and thermal print head (TPH) temperature in a thermal printer of the type having,
- said thermal print head (TPH), which receives a strobe signal and printing data, including heating elements which produce dots on a printing medium when said heating elements are heated during a heating period,
- gradation controlled printing means, which outputs the printing data to said TPH, for printing a line of input data according to a gradation scale corresponding to a predetermined number of gradation levels by causing said TPH to print a number of successive dots for a given pixel, the number of dots printed depending upon the gradation scale and said value of the input data for the given pixel,
- a system for compensating for common drop and TPH temperature comprising:
- first detecting means, which receives the line of input data and an addressing data output from said gradation controlled printing means, for developing data representing a number of dots simultaneously printed by said TPH in a given gradation level of printing;
- second detecting means for developing data representing the temperature of said TPH;
- correcting means which outputs the strobe signal to said TPH responsive to said data from said first and second detecting means for controlling the heating period of said TPH during printing of each gradation level to compensate for the temperature of said TPH and the common drop during each gradation level of printing.
A method for compensating for common drop and thermal print head (TPH) temperature in thermal printer of the type having,
- said thermal print head (TPH) including heating elements which produce dots on a printing medium when said heating elements are heated during a heating period,
- gradation controlled printing means for printing a line of input data according to a gradation scale corresponding to a predetermined number of gradation levels by causing said TPH to print a number of successive dots for a given pixel, the number of dots printed depending upon the gradation scale and a value of the input data for the given pixel,
- said method for compensating for common drop and TPH temperature comprising the steps of:
- developing data representing a number of dots simultaneously printed by said TPH in a given gradation level of printing;
- developing data representing the temperature of said TPH;
- controlling, in response to said data representing the number of dots simultaneously printed and said data representing the temperature, the heating period of said TPH during printing of each gradation level to compensate for the temperature of said TPH and the common drop during each gradation level of printing.
Dependencies are inferred from the claim text.