| 摘要 |
PURPOSE:To attain to uniformize heat generating quantity at every block, by determining the strobe time of the drive power applied to each block by referring to each preliminarily calculated average resistance value at every block. CONSTITUTION:Test voltage Et is selected under the control of a controller 2 by a switch circuit 3 at the time of non-recording to be applied to a thermal head 1 and, after a strobe signal STB1 was applied to a switching element STB-Q1, the heat generating elements H at several bits present at the predetermined specific positions of a first block B1 are selected as a test objects by using dummy data and respectively successively driven to generate heat. The potential at each (a)-point at that time is successively detected by the controller 2 and the average resistance value of the heat generating element H coming to the test objects in the first block B1 is calculated on the basis of the respectively detected value. The proper strobe time of applying drive voltage Es to each of blocks B1-Bm is determined by the controller 2 so as to uniformize the heat generating quantity of each bloc, that is, recording density. |
