| 摘要 |
A latent image structure comprises an array of relief elements (5) defining: i) a first latent image ("D") viewable along a first line of sight offset to the normal; ii) a second latent image ("20") viewable along a second line of sight offset to the normal, the second line of sight being rotated laterally relative to the first line of sight about a normal to the structure, the first and second latent images being superimposed. The relief elements (5) define, for each latent image, portions of respective linear relief structures providing an image and a background which cooperate to generate the latent image, and wherein the relief elements are only provided at locations where the linear relief structures of the first and second latent images intersect. |
