Optical Metasurface Generated Vector Beam for Anticounterfeiting

With the rapid development of optical metasurfaces, the anti-counterfeiting methods continue to evolve. Recently, the unprecedented capability of optical metasurfaces in the local manipulation of the light’s polarization has been used to generate arbitrary polarization profiles, providing an unusual method for anti-counterfeiting. We experimentally demonstrate a metasurface device that can hide a quick response (QR) code in the polarization profile of a laser beam. The desired space-variant polarization profile originates from the superposition of two circularly polarized light beams with opposite handedness based on a single metasurface. A linear polarizer is used to reveal the hidden QR code. The anti-counterfeiting property of such a device has potential application in product identification, item tracking and document management.