Concealed holographic coding for security applications by using a moire technique

Xiangsu Zhang, Erik Dalsgaard

Research output: Contribution to journalJournal articleResearchpeer-review


We present an optical coding technique that enhances the anticounterfeiting power of security holograms. The principles of the technique is based on the moire phenomenon. The code in the hologram has a phase pattern that is invisible and cannot be detected by optical equipment, so that imitation is extremely difficult. Holographic, photographic and embossing technique are used in fabricating coded holograms and decoders.
Original languageEnglish
JournalApplied Optics
Issue number31
Pages (from-to)8096-8097
Publication statusPublished - 1997

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