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The drawing shows unpolarized light entering the y-oriented polarizing filter at the base of the structure. The x-polarized component is filtered out, and only the y-polarized component is allowed to pass through. This light passes through a y-oriented entrance substrate and an x-oriented exit substrate, both of which have orthogonal groove orientations. Rod-shaped molecules in between these substrates rotate the light by 90 degrees. The light beam passes through an x-oriented polarizing filter which allows the rotated light to pass through, and an x-polarized light comes out on top through a slit.