The study by Nair et al. investigates the optical transparency of suspended graphene, finding that it is defined by the fine structure constant, \(\alpha = e^2/hc\). Despite being only one atom thick, graphene absorbs a significant fraction of incident white light, approximately 2.3%, which translates to a universal dynamic conductivity \(G \approx e^2/4h\). The research uses large graphene crystals prepared by micromechanical cleavage and fabricated into membranes with apertures. Optical measurements reveal that graphene's opacity is independent of wavelength and increases proportionally with the number of graphene layers. The findings are consistent with theoretical predictions based on the properties of 2D Dirac fermions, demonstrating that graphene's optical properties are fundamentally determined by fundamental constants. This work highlights the unique optical behavior of graphene and its potential for metrological applications.The study by Nair et al. investigates the optical transparency of suspended graphene, finding that it is defined by the fine structure constant, \(\alpha = e^2/hc\). Despite being only one atom thick, graphene absorbs a significant fraction of incident white light, approximately 2.3%, which translates to a universal dynamic conductivity \(G \approx e^2/4h\). The research uses large graphene crystals prepared by micromechanical cleavage and fabricated into membranes with apertures. Optical measurements reveal that graphene's opacity is independent of wavelength and increases proportionally with the number of graphene layers. The findings are consistent with theoretical predictions based on the properties of 2D Dirac fermions, demonstrating that graphene's optical properties are fundamentally determined by fundamental constants. This work highlights the unique optical behavior of graphene and its potential for metrological applications.