| 摘要 |
PURPOSE:To eliminate the need of a manual adjustment, and to automatically compensate a temperature drift and time aging by constituting the title controller so that an optical output of a laser diode is varied by an optimum pattern in accordance with a scanning speed of a laser spot. CONSTITUTION:Whenever a power set signal is inputted, data corresponding to a driving current ILP for outputting the maximum value PP of an optical output which is set in advance by a laser diode, and data corresponding to a difference ILD between a driving current ILB for outputting the minimum value PB of an optical output which is set in advance in the same way and the driving current ILP are stored in a first storage means 20 and a second storage means 30, respectively. In such a state, in accordance with a control signal outputted from a control signal synthesizing means 43, the driving current of the laser diode is controlled by a laser diode control means 8. In such a way, the driving current is controlled so that the optical output of the laser diode 1 is varied in accordance with a scanning speed of a laser spot by the laser diode 1 on the surface to be scanned. Therefore, the manual adjustment is made unnecessary, and a temperature drift and time aging are also compensated automatically. |
