When a liquid crystal coating (LCC) is illuminated from the normal direction by white light and observed from an oblique above-plane view angle, its color-change response to shear depends on both shear stress vector magnitude and the direction of the applied shear vector relative to the observer's in-plane line of sight. At any point, the maximum color change is always measured when the local shear vector is aligned with, and directed away from, the observer; the magnitude of the color change at this vector/observer aligned orientation scales directly with shear stress magnitude.
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