Is that a real Rolex, or a fake? Thanks to research currently being carried out at Switzerland's Ecole Polytechnique Fédérale de Lausanne (EPFL) research institute, an ultraviolet lamp may soon be all that you need to tell the difference between luxury watches and knock-offs.
The "DNAwatch" technology is actually being developed by EPFL spinoff company Nanoga, and involves what is being referred to as a nanoscopic watermark.
Using a machine ordinarily used for manufacturing LEDs, a proprietary blend of chemicals is applied to a glass surface as a vapor, forming into photonic crystals. These crystals are in turn made up of ultrathin layers of atoms, and they convert UV light into colors – different colors can be produced by tweaking the geometry and alignment of the crystals on the glass.
Lithographic printing techniques are used to mask some areas of the surface, so that the watermark takes on a watch-specific pattern. When viewed under visible light, that pattern is invisible to the human eye, in no way altering the watch's appearance. Under UV light, however, the watermark shows up.
According to EPFL, counterfeiting such a watermark would be as difficult as forging the Swiss 50-franc note. Not only would counterfeiters need to know which chemicals to use and in what proportions, but they would also need expensive equipment to apply them.
A variation on the process should reportedly also work on ceramic and metal surfaces. Nanoga is currently shopping the DNAwatch technology around to various luxury watchmakers.
More information is available in the following video.