(a) Modification to the PiP process for conformal imprint, showing the addition of non-planar aluminum tool (gray) for homogenous pressure application normal to the imprinting surface. (b) Lens characteristics, 9.8 mm radius of curvature, 15 mm diameter. Inset: Imprinted lens, using optimized PiP method. (c) Transfer of film imprinted on lens to skin as example curved biological surface (scale bar 4 mm). Inset: change in colorimetric response of the imprinted film with the addition of ethanol to the surface (scale bars 1 mm). (d) AFM topology of conformal PiP imprint, with dashed line corresponding to cross-section Scale bar 5μm. (e) AFM cross-section of conformal imprint, showing good pattern replication across all dimensions.