| 摘要 |
PURPOSE:To scan two lines at a time so as to heighten resolution and printing grade by providing two kinds of control means for controlling emission of two kinds of light sources so as to irradiate a predetermined position on a photosensitive body with light. CONSTITUTION:A printer engine starts printing operation in response to a vertical synchronizing signal VSYNC from a printer controller. The printer controller outputs a data of a first line of an image signal from a VDOa and outputs a data of a second line from a VDOb so as to light twin beam laser. From the VDOa, an image data at odd line is sent out. From the VDOb, an image data at even line is sent out. Here, an image clock VCLK having a frequency double that of 300 dots/inch (2V[MH2]) is used for providing image signal with double information quantity in 1 line respectively. As two signals are provided for the image signal, the controller sends out an image signal with information quantity of 4 times in all to the printer engine. |
