Measurement of skin stretch using digital image speckle correlation

Background/purpose: The surface of the skin is covered by intersecting grooves and ridges which produce characteristic skin surface patterns. It has been suggested that these folds provide a reserve of tissue, allowing the skin to stretch during normal muscle movements. More so, skin is anisotropic and under constant tension. Therefore, to characterize skin displacement following stretch, a discrete, description of the in‐plane skin displacement during stretch is of interest. We introduce the use of digital image speckle correlation (DISC), a non‐contact technique, to map, in two dimensions, the surface deformation patterns resulting from skin stretching.