| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a copy-preventive pattern of developing a remarkably pattern by a moire in a digital copier by providing printing elements quantitatively continuously expanded by a fine printing element width outward of the part at the border line of a character or a symbol mark, and providing picture elements contracted and arranged by the fine printing element width inward. SOLUTION: A line (αline) group of straight lines and curves having a finer printing element width than that of the line segment of the border line of the character and graphic form group to form an arithmetic progression inward and outward from the character and graphic form group is formed based on the line segment of a border line for constituting the character and graphic form group. The a line outward from the line segments of the border line for constituting, for example, a character and graphic form group 'A, B' from the pattern formed according to this plotting method is formed with straight line constituting areas f1, f1' at the area surrounded by the sides for coupling the sides for coupling the vertexes a2, a3 of the character and graphic form 'A' and the vertexes b1, b5 of 'B', and with the sector-like constituting areas f2, f2' of the concentric circular arc parallel line state and arbitrary curve constituting areas f3, f3', thereby obtaining a copy-preventive function.</p> |
