摘要 |
An article, such as a film, comprising a body portion and a surface portion is provided. The body portion has (i) a first and a second surface, and (ii) first and second in-plane axes that are orthogonal with respect to each other and a third axis that is mutually orthogonal to the first and second in-plane axis in a thickness direction of the body. The surface portion comprises a linear geometric feature disposed on the first surface of the body in a direction substantially parallel to the first in-plane axis of the polymeric body. The article has (i) a first index of refraction (n<SUB>1</SUB>) along the first in-plane axis, (ii) a second index of refraction (n<SUB>2</SUB>) along the second in-plane axis, and (iii) a third index of refraction (n<SUB>3</SUB>) along the third axis, wherein n<SUB>2 </SUB>and n<SUB>3 </SUB>are substantially the same but substantially different from n<SUB>1</SUB>; and wherein the uniaxially oriented polymeric film has a relative birefringence of 0.3 or less and wherein the ratio of the thickness of the body to the height of the geometric feature is at least 2.
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