Pyrographic Patents (Class 178/94)
  • Patent number: 3934695
    Abstract: The quality of thermally printed characters is enhanced by controlling the time at which and the time for which power is applied to the resistive printing elements in a battery-operated moving-head thermal dot matrix printer. By sequentially strobing the elements in the pattern of the character to be formed as the print head moves across thermal sensitive paper, a high-quality slanted character is printed and parasitic losses are reduced. By inversely varying the time power is supplied to each dot as battery voltage varies, character quality is maintained and useful battery life is extended.
    Type: Grant
    Filed: September 23, 1974
    Date of Patent: January 27, 1976
    Assignee: Hewlett-Packard Company
    Inventor: Albert W. Kovalick