| 摘要 |
PURPOSE:To correctly obtain a printing density of a designated gradation code, by converting an inputted gradation code showing n steps of gradations into a printing energy signal so as to obtain the density indicated by the inputted gradation code by m steps of gradations in accordance with a characteristic controlling signal. CONSTITUTION:A line counter 3a reads out 4-bit gradation codes B0-B3 of each heat generating element of a line buffer 3, and a table ROM 20 converts the codes B0-B3 into 8-bit gradation codes b0-b7. A 256 counter 23 selects a bit d0 of 256-bit time width data d0-d255 converted in a table ROM 21 at the initial time, and then selecting sequentially d1, d2,... d255. In other words, at the first reading of the line buffer 3, the first bit of the time width data of each element 1c is set in a one-line shift register 1a. As the heat generating element 1c is electrically driven, one line is printed in 256 gradations. |
