| 摘要 |
PURPOSE:To form an image at high speed by supplying a current between an electrode and a current supplying electrode to locally heat a heating film, and locally heating a heat sensitive sheet by the heat, thereby significantly shortening the period of a driving pulse supplied to the electrode. CONSTITUTION:A heat sensitive sheet 32 is disposed on a platen 28, and a conductive electrode 36 can be locally contacted through a heating film 42 on the sheet 32. The electrode 36 is connected with a driving circuit 45 to supply a driving current pulse from the circuit 45 through the electrode 36, a resistance layer 20 and a conductive layer 18 on an earth. When an image is formed on the sheet 32, the film 42 itself is locally heated, the heat is transmitted to the sheet 32 to locally heat it. Thus, the heated portion is colored to form the image. Accordingly, the heat is not almost stored in the electrode 36. Thus, the period of the current pulse supplied to the electrode 36 can be significantly shortened, thereby efficiently forming a heat sensitive image at high speed. |
