| 摘要 |
PURPOSE:To realize the highly faithful reproduction of recording information having medium density such as a video signal, by appropriately selecting a voltage detection terminal corresponding to the current supply state to a heat generating element and detecting voltage applied to a heat generating resistor to feed back the same to a power source. CONSTITUTION:The switch of a heat generating element driven by an external signal source is provided in a thermal recording head 2 and the heat generating element is appropriately selected corresponding to an external signal to receive the supply of a current. At this time, voltage, which is applied to the heat generating element from a plurality of voltage detection terminals 4 provided to the common electrode for supplying a current to the heat generating element by a falling voltage detection circuit 5, is detected and fed back to a power source 1 to control voltage applied to the heat generating element from the common electrode so as to make the same constant. Because the quantity of energy per one element applied to the heat generating element in the thermal recording head can be made constant regardless of the number of elements driven simultaneously, highly accurate medium density recording can be performed stably. |
