Cost-Efficient Printing of Graphene Nanostructures on Smart Contact Lenses

Smart contact lenses have been put forward for years, but there is still no commercial product in the market; the high cost due to expensive fabrication techniques could be one of the reasons. In this paper, first, a cost-efficient and reliable route to fabricate graphene grating on contact lens was designed and demonstrated based on the direct laser interference patterning graphene film on commercial contact lenses using an Nd:YAG laser. The thickness of the film and the interference angle have been taken into consideration. Optical characterization and simulation have been applied to evaluate the quality of our final achieved grating patterns with a grating size from 0.92 to 3.04 μm. Two-dimensional (2D) patterns could also be obtained through double-time laser interference. Contact angles for samples with different interference angles were presented considering the service environment of smart contact lenses. Of course, the conductivity of the samples was evaluated using a four-probe method. The most conductive sample had the sheet resistance lower than 30 Ω/sq. This research study highlighted the possibility of patterning graphene with the laser ablation method and provided a candidate solution for the fabrication of smart contact lenses under controlled cost.