摘要 |
An article of manufacture including an optically variable surface pattern is disclosed. The optical surface pattern makes visible one out of a plurality of N image representations for each one out of N predetermined viewing directions. The surface pattern comprises M grating elements, each of the grating elements being divided into N grating element sub-portions. Each of the N sub-portions of each grating element contains a diffraction element in the form of a relief structure with predetermined parameters for diffracting incident light. Each of the sub-portions of each grating element thereby corresponds to one pixel of one of the N image representations, so that one of the N image representations is visible from each of said predetermined viewing directions.
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