Copy-resistant document

摘要: A document that resists copying by ordinary color copiers and scanners. An area is printed with dots using a gradient print screen exceeds resolutions available on commonly The may therefore comprise lighter regions (having fewer lines per inch) darker more inch). Multiple colors be different screens, which are or for first not second color. also moire pattern. pattern generated adjusting an angle between pair of such as screens. set printing avoid common ink colors, prefer yellow, light green, blue, red, purple, violet, to raise the difficulty in top layer covered matte varnish transparent white ink.