Patent ID: 7674028

Claim:
An optical member comprising an array of total internal reflection structures, said optical member comprising: a substantially optically transmissive film having a surface; a first plurality of non-intersecting elongate features in said surface; and a second plurality of non-intersecting elongate features in said surface, said first plurality of non-intersecting elongate features angled with respect to said second plurality of non-intersecting elongate features, wherein each of said non-intersecting elongate features in said first plurality extends across said non-intersecting elongate features in said second plurality of non-intersecting elongate features thereby forming said total internal reflection structures, and wherein said non-intersecting elongate features comprise grooves and the depth of at least a portion of said second plurality of non-intersecting elongate features is smaller than the depth of at least a portion of said first plurality of non-intersecting elongate features but that is greater than 50% of the depth of said portion of said first plurality of non-intersecting elongate features.