摘要 |
The invention is an improved arrangement for illuminating a liquid crystal cell which provides a significant increase in the range of viewing angles in a plane orthogonal to the principal viewing plane which is defined as the plane containing the director at the midpoint of the liquid crystal and the normal to the light entry surface. The improvement comprises means for illuminating the cell having a substantially collimated beam in the orthogonal plane. Preferably, the thickness of the liquid crystal in the cell corresponds to the first Gooch-Tarry minimum. The invention is also a method for providing a wide angle for a liquid crystal display comprising the step of illuminating a liquid crystal cell with a beam of light which is substantially collimated in the principal viewing plane and which is substantially uncollimated in an orthogonal plane.
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