Grating material can have security effects in print for its specific optical properties. In this paper, the technology of copyright protection used in Screening Copy is studied basic on the optical properties of cylindrical lens sheet and screening. Firstly, the relation of the parameter of cylindrical lens sheet and the parameters of half-tone image is studied. Achieving the arithmetic what used to set dot basic on the relation. Secondly, imitating the experiment in Photoshop cs2 and setting dot after transferring the image to halftone use the screening of it. Meanwhile, generate the layer which has the effect of cylindrical lens sheet and can get the imitate effect while rotate the layer. In the experiment, using the printer of Epson 7880 to print the image and examining the security through corresponding cylindrical lens sheet. The experiment proves the hidden information only can be seen though cylindrical lens sheet and it shows the anti-counterfeit way have well effect in screening copy. And the equipment and processes are not needed too much for this way, so the anti-counterfeit effect can be achieved in the condition of not adding cost.