| 摘要 |
PURPOSE:To enable faithful and stable revisualization of an image in color in a highlight part or a high density part by forming a temporary image signal through addition of a color-resolved image signal to an image signal of a non- output cumulative image signal of the same color, and turning a light beam on/off in accordance with a PWM signal corresponding to an output image signal after comparison of the temporary image signal with a prearranged threshold value and error diffusion processing. CONSTITUTION:The density 18 of an input image G13 is entered into an addition circuit 261. At that time, a temporary density 38 is output to an output terminal O of the addition circuit 261, as a cumulative error density 20 is held by a register 262. Further, this density 38 is supplied to registers 262, 263 as well as CMP 264. CMP 264 compares the temporary density 38 with a threshold value 32 to determine which is a larger value. At this moment, a logic O level signal of D<C from an output terminal contrarily enables the RESET function of the register 262, as the D<C conditions are not satisfied, and a data load function into the register 263 is enabled. Consequently, an input image G13 is printed with an output density 38 and the cumulative error of a micro area is diffused. |
