Abstract: A computer generated moire identification system mainly uses two kinds of computer generated grids, one called object grids, and the other, reference grids. An object grid is used as an information carrier. The necessary specific information for identification such as the owner's signature or photograph is read into a computer, which codes the information into a grid, and then prints the code information onto an I/D plate or card. It is impossible to find out the hidden information by merely inspecting this plate. However, the coded information will reappear when the I/D plate is placed in a read-out machine, where the reference grid decodes the coded information in the form of Moire patterns.