Figure 5.

Maps of axial stress produced by a stiff silicone cube, reconstructed using the (a) algebraic and (b) computational method. (c) Cross-sectional OCT image of the sample; arrow shows micro-scale surface perturbations. (a–c) Scale bar, 300 µm. (d,e) Cross-sectional plots of stress along the x-direction (horizontal; through the centre of (a,b)), (d) simulated, and (e) experimental; reconstructed using the algebraic and computational approaches, respectively. (f) Demonstration of computational optical palpation on a 5-cent Australian coin, 19 mm in diameter (i); map of tactile stress (ii). Scale bar, 1 mm. (Online version in colour.)