Fig 1.
(A) Block diagram of the measurement system. (B) Schematic showing test specimens loaded in compression and tension on the measurement stage.
Fig 2.
(A) PLM image of porcine optic nerve head tissue roughly flush with the globe’s surface. Raman scan of two points (B) and (C) having distinctly different visual features shown as cross-marks on the image. Fig (D) Indicates the Raman spectra for Collagen I showing the following characteristic peaks: A = three characteristic peaks related to pyrrolidine ring of proline backbone of collagen. (~855 cm-1), B = Amide III (~1320 cm-1), C = Amide II (~1490 cm-1), D = Amide I (~1640 cm-1) and E = C-H stretch (~2900 cm-1).
Fig 3.
Polarized light microscopy of a sample of porcine scleral tissue near the optic nerve head.
The figure shows the intricate network of the collagen fibers in the tissue in the un-deformed condition. The scale bar in the image indicates 10 μm.
Fig 4.
Hyperspectral chemical images of the collagen network of porcine scleral tissue in un-deformed (A) and deformed (D) states generated by the spatially correlated CRM imaging technique. The figure also shows the corresponding PLM images (B, C, E and F) of the same tissue. The horizontal direction in each image corresponds to the direction in which deformation is applied to the overall sample.
Fig 5.
PLM of porcine sclera microstructure under global sequential compression of a tissue sample followed by unloading.
Numbers under the images indicate global deformation of the tissue sample. The horizontal direction in each image corresponds to the direction in which deformation is applied to the overall sample. The scale bar is 90 μm.
Fig 6.
Collagen fibers in a sample of porcine sclera under tensile loading.
(A) PLM images and (B) calculated normal strain ϵxx. The arrows indicate the direction in which tensile deformation is applied to the overall 8mm X 8mm sample. The scale bars in the figure(s) represent 90 μm.