Fig. 1.

DIC-EIS of collagen fibrils. (a) Vibration direction of analyzer and polarizer in an inverted microscope and the resulting shearing direction. (b) Schematic of a collagen fibril oriented perpendicular to the shear axis. (c) Intensity profile across the collagen fibril along the shear axis when the fibril diameter is larger than the diffraction limit of visible light microscopy. The final image has spatially separated intensity amplitude shifts and the specimen’s size can be determined using conventional imaging techniques. (d) Intensity profile across the collagen fibril along the shear axis when the fibril diameter is smaller than the diffraction limit of visible light microscopy. The intensity amplitude shifts along the shear axis are not completely resolved.