| 摘要 |
PURPOSE:To enable multi-gradation representation through multi-level recording, by making the width at a joint of an electrode to a heating element narrower than the effective recording width of the heating element, then controlling the time for applying voltage onto the heating element and representing gradation. CONSTITUTION:The width of a connecting electrode 2 of each heating element 1 in a plurality of heating elements arranged in a line is made narrower than the width of the heating element. Consequently, almost all current flows within a width corresponding to the width of the electrode 2 of the heating element 1 for a current level lower than a predetermined level, and the temperature only at a portion corresponding to the width of the electrode 2 increases particularly thus exhibiting a high temperature difference with respect to other portions. When the time for applying a pulse voltage is increased gradually in order to vary the applying energy, ink is fused under an area having higher temperature than the melting point Tm of ink in an ink sheet and transferred to a recording sheet. Consequently, the high temperature area of dot to be transferred varies as shown by 42A, 43A, 44A. In such a manner, fluctuation of density in an intermediate tone recording can be reduced by controlling the time for applying pulse voltage. |
