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Creators/Authors contains: "Wong, Chau-Wai"

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  1. Paper surfaces can be used for anticounterfeiting due to their inherent and physically unclonable irregularities. Prior work used mobile cameras to capture paper's microstructure with the help of camera flash. However, prolonged exposure to flash in the workplace may harm the eyes of workers involved in the authentication process. This work proposes an authentication method that exploits indoor lighting without the need for a camera flash. Indoor lighting has a lower strength and leads to interference due to secondary reflections, making it challenging to achieve a good authentication performance. To this end, we create a digital twin (DT) replication of a real world in which paper patches are captured under multiple lights, taking account of key physics and optical laws. From simulations of DT, we identify important factors to the authentication performance and design an authentication method for an office setup. We have experimented with three different types of paper and showed that the DT-guided authentication method can achieve satisfactory authentication performance without using active light sources. 
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    Free, publicly-accessible full text available August 7, 2025
  2. Free, publicly-accessible full text available July 1, 2025
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