Fig. 6: Simultaneous control over stimulus-reconfigurable optical appearance, shape transformation, and surface texture.
Halftone pattern-encoded growth functions enabling the transformation of 2D hydrogel films into axisymmetric non-Euclidean 3D shapes, including spherical caps (a, b) and hyperbolic saddles (c, d). The design principles are established through the relationships among areal deswelling ratios (A35°C/A0), grayscale levels (G1-G9), and the relative radius of concentric rings (r/R) (a, c). Halftone-regulated grayscale images in (b, d) were produced using MathWorks MATLAB software. e–h Co-designed halftone patterns simultaneously regulate optical information and growth functions, revealing encoded letters and graphics as the 2D film morphs into prescribed 3D caps. i–l Shape-morphing of complex surface morphologies featuring varying local Gaussian curvatures (positive, negative, or hybrid) and halftone pattern-regulated textures. Scale bars, 10 mm (e, g), 5 mm (f, h, j, k), 2 mm (l).
