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Abstract

In this paper, we propose a new approach for fabrication processes of microstructures composed of diffractive optical elements (DOE) and security elements. The holographic lithography is combined with laser lithography to obtain highly secured holographic labels for products protection. The secret key is an untraceable and hardly reproducible geometry and can be embedded in the labels or stickers to increase the level of security and diminish the possibility of products counterfeiting. In our process, the holographic structure composed of DOEs, and the key are designed separately by two authorized designers and recombined using double exposure followed by a single development step. The layout of microstructures that composes the security key are known only by the designer.

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