SUTD – Hongtao Wang, Hao Wang, John You En Chan, Wang Zhang, Soroosh Daqiqeh Rezaei and Joel Yang
University of Shanghai for Science and Technology (USST) – Min Gu
Harbin Institute of Technology – Qifeng Ruan
National University of Singapore – Cheng-Wei Qiu
A*STAR – Hailong Liu and Jonathan Trisno
SUTD led research in a 3D printed optical security label with nano-sized features. It taps on ambient light sources and is harder to crack due to its 33100 possible combinations.
The video shows the optical security label or photonic tally, consisting of colored vortex beam array. The photonic tally turns into colorful dots when overlapped with each other. During this process, the color and OAM (orbital angular momentum) information is decoded.
Each year, an estimated two trillion dollars is lost globally due to counterfeit products ranging from jewelry to medicine. As current security labels and product authentication methods are rapidly becoming obsolete or easy to hack, there is a rising urgency for more secure anti-counterfeiting labels.
A research team fabricated a 3D printed nano optical security label that provides 33100 possible combinations for heightened security in optical anti-counterfeiting. Associate Professor Joel Yang and team from the Singapore University of Technology and Design (SUTD) collaborated with Professor Min Gu from University of Shanghai for Science and Technology (USST) and Associate Professor Cheng-Wei Qiu from National University of Singapore (NUS), along with their respective teams and published their research paper, ‘Coloured vortex beams with incoherent white light illumination’ in Nature Nanotechnology.
The research team achieved such a feat by exploiting higher dimensional structured light, i.e., coloured Orbital Angular Momentum (OAM) beams, through the fabrication of 3D printed spiral phase plates. Importantly, these plates were miniaturised down to a diameter smaller than that of a strand of human hair and further integrated with structural colour filters – spiky looking structures that allow specific colours of light through (refer to image below).
You can find more details at https://www.sutd.edu.sg/Research/Research-News/2023/3/Casting-light-counterfeit-nano-optical-tech