| 摘要 |
PURPOSE:To eliminate a moire to be generated on a gravure screen, by using a pattern including a combination of an irregularly folded lines and smooth curved lines or irregularly and curved smooth lines. CONSTITUTION:The intersections (e.g., A-F) of a pattern containing 2-dimensional regular squares adjacent to each other are shifted at random (e.g., average shift distance: about 1/4 length of a side of a square, standard deviation: about 1/8 length of a side of a square; shift direction: all angles around intersections). Then the obtained points A'-F' are connected in correspondence to the forming segments of lines of the original square to obtain a pattern containing folded lines. Using this pattern, a gravure screen is formed. Each segment of line of a pattern including irregular folded lines can be converted into a segment which is approximated with a smooth curved line. |
