Sunscreen Nanoparticle UV Filter Simulator (2D)

Mineral sunscreen filters — titanium dioxide and zinc oxide — work because they are ground down to nanometre scale, not despite it. This 2D cross-section simulator draws an instanced field of TiO₂/ZnO nanoparticles on a skin line and rains UV photons onto it, computing a real Mie size-parameter and an anomalous-diffraction-theory extinction efficiency for every combination of particle radius and wavelength you choose, alongside a semiconductor bandgap-absorption spectrum that drives the photocatalytic reactive-oxygen-species trade-off a silica surface coating is designed to suppress. Two live plots — the Qext(λ) extinction curve and the absorption/ROS spectrum — move with every slider, and the cross-section panel is fully pannable and zoomable.