Light enhancing structures with a plurality of arrays of elongate features
View Patent ↗Various embodiments comprise light recycling films comprising an array of parallel ridges and grooves that form prisms that selectively reflect or transmit light. In some embodiments, the light recycling film may be used in displays that include spatial light modulators comprising a plurality of pixels. The light recycling film can limit the field-of-view of the display and enhance the luminance within that field-of-view. Various embodiments comprising multiple arrays of ridges and/or grooves can enhance uniformity of illumination of the pixels in the spatial light modulator and reduce Moiré effects.
1. An optical member comprising an array of total internal reflection structures, said optical member comprising:
an optically transmissive film having a surface;
a first plurality of non-intersecting elongate features formed in said surface; and
a second plurality of non-intersecting elongate features formed in said surface, said first plurality of non-intersecting elongate features being oriented at an angle with respect to said second plurality of non-intersecting elongate features that is less than 30°,
wherein each of said non-intersecting elongate features in said first plurality extends across said multiple non-intersecting elongate features in said second plurality thereby defining said total internal reflection structures, and at least one of said total internal reflection structures comprises a prism having planar facets each having substantially the same projected area.
2. The optical member of claim 1 , wherein at least two of said non-intersecting elongate features comprise substantially parallel linear features.
3. The optical member of claim 1 , wherein at least one of said non-intersecting elongate features varies in height or depth along its length.
4. The optical member of claim 1 , wherein at least one of said non-intersecting elongate features comprises non-linear features.
5. The optical member of claim 4 , wherein said non-linear feature undulates laterally.
6. The optical member of claim 1 , wherein said non-intersecting elongate features comprise grooves.
7. The optical member of claim 1 , wherein said non-intersecting elongate features comprise ridgelines.
8. The optical member of claim 1 , wherein said prism comprises a pyramid.
9. The optical member of claim 1 , wherein said planar facets have rounded edges.
10. The optical member of claim 9 , wherein said angle is less than 10 degrees.
11. The optical member of claim 1 , wherein said total internal reflection structures comprise inverted pyramids.
12. The optical member of claim 1 , wherein said total internal reflection structures comprise everted pyramids.
13. The optical member of claim 1 , wherein at least one of said total internal reflection structures comprises curved surfaces that totally internally reflect light.
14. The optical member of claim 1 , wherein said film comprises a polymer.
15. The optical member of claim 1 , wherein at least one of said first plurality and second plurality of non-intersecting elongate features has a vertex angle of about 89.25°.
16. The optical member of claim 1 , further comprising a diffuser on either side of said surface.
17. The optical member of claim 1 , wherein at least one of said non-intersecting elongate features is linear.
18. An optical apparatus comprising the optical member of claim 1 and an illumination apparatus that backlights said optical member.
19. The optical member of claim 1 , wherein each of said non-intersecting elongate features in said first plurality intersects each of said non-intersecting elongate features in said second plurality only once.
20. The optical member of claim 1 , wherein said angle is less than 10 degrees.
21. The optical member of claim 1 , wherein said first plurality and second plurality of non-intersecting elongate features have pitches greater than 30.5 um.
22. The optical member of claim 1 , wherein said film has a thickness of 0.2 mm or less.
23. An optical member comprising an array of total internal reflection structures, said optical member comprising:
an optically transmissive film having a surface;
a first plurality of non-intersecting elongate features formed in said surface; and
a second plurality of non-intersecting elongate features formed in said surface, said first plurality of non-intersecting elongate features being oriented at an angle with respect to said second plurality of non-intersecting elongate features that is less than 10°,
wherein each of said non-intersecting elongate features in said first plurality extends across said multiple non-intersecting elongate features in said second plurality thereby defining said total internal reflection structures.