| 摘要 |
PURPOSE:To prevent the occurrence of streaks, by a construction wherein, in matrixes of arrangement of thresholds, one matrix arrangement is successively shifted to the other matrix arrangement and the thresholds in these matrixes are used in order. CONSTITUTION:A basic matrix Mo and 1st-3rd matrixes M1-M3 having columns successively shifted to the basic matrix Mo are stored in a memory part 31 so that the thresholds of the same column of each matrix are repeatedly fetched in order. In this manner, the possibility that the same threshold of the same arrangement is repeatedly outputted by every picture element as shown in a conventional device is eliminated, which results in the output of different thresholds per picture element. Thus, the same pattern with respect to the density of each picture element can be broken. In this manner, the occurrence of streak can be prevented. |
