Light redirecting films with non-prismatic optical elements

• US 8,845,176 B2
• Filed: 05/14/2013
• Issued: 09/30/2014
• Est. Priority Date: 02/23/1999
• Status: Expired due to Fees

• Current Assignee: Rambus Delaware LLC (Rambus Inc.)
• Original Assignee: Rambus Delaware LLC (Rambus Inc.)
• Inventors: Parker, Jeffery R., McCollum, Timothy A., Ezell, Robert M.
• Primary Examiner(s): Negron, Ismael
• Application Number:
  US13/893,886
• Publication Number:
  US 20130329432A1
• Time in Patent Office: 504 Days
• Field of Search: 362/618, 362/620, 362/624, 362/625, 362/626, 362/619, 362/330, 362/339, 362/622, 362/623, 362/615, 359/599, 359/615, 385/130
• US Class Current: 362/626
• CPC Class Codes: A61B 2090/309 using white LEDs
• CPC Class Codes: A61M 2021/0044 by the sight sense
• CPC Class Codes: A61M 21/02 for inducing sleep or relaxation, e.g. by direct nerve stimulation, hypnosis, analgesia for massage A61H; electrotherapy A61N, e.g. applying alternating or intermittent electric currents for producing anaesthesia A61N1/36021
• CPC Class Codes: A61N 2005/063 comprising light transmitting means, e.g. optical fibres
• CPC Class Codes: A61N 2005/0652 Arrays of diodes
• CPC Class Codes: A61N 5/0621 Hyperbilirubinemia, jaundice treatment
• CPC Class Codes: F21V 11/00 Screens not covered by groups F21V1/00, F21V3/00, F21V7/00 or F21V9/00 characterised by cooling arrangements F21V29/502
• CPC Class Codes: F21V 5/10 comprising photoluminescent material
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/002 by shaping at least a portion of the light guide, e.g. with collimating, focussing or diverging surfaces
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/006 to produce indicia, symbols, texts or the like
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects
• CPC Class Codes: G02B 6/0068 : Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: H01H 2219/062 : Light conductor
• CPC Class Codes: H01H 2221/07 : transparent

Abstract

An optical assembly includes a light emitting panel having a light output surface with non-uniform directional light output distribution, and a light redirecting film located to receive light emitted from the light output surface. The light redirecting film has a pattern of individual non-prismatic optical elements of well defined shape with a total of two surfaces that intersect each other, the shape varying at different locations on the light redirecting film to redistribute the light received from the light output surface within a desired light ray angle distribution.

Claims

1. An optical assembly, comprising:

a light emitting assembly comprising a light emitting panel and a light source optically coupled to the light emitting panel, the light emitting panel having a light output surface that has a non-uniform directional light output distribution; and

a light redirecting film located to receive light emitted from the light output surface, the light redirecting film having a pattern of individual optical elements of well defined shape that vary in shape at different locations on the light redirecting film to redistribute the light received from the light output surface within a desired light ray angle distribution, wherein a plurality of the individual optical elements are non-prismatic optical elements, each of the non-prismatic optical elements having a total of two surfaces, the two surfaces intersecting each other.

2. The optical assembly of claim 1, wherein the two surfaces are curved surfaces.

3. The optical assembly of claim 1, wherein the individual optical elements are randomized in slope angle, size, shape, height, depth, or density.

4. The optical assembly of claim 1, wherein the individual optical elements are oriented at different angles relative to each other such that the light redirecting film redirects the light along two axes.

5. The optical assembly of claim 1, wherein one of the two surfaces is a curved surface and another of the two surfaces is a planar or flat surface.

6. The optical assembly of claim 5, wherein the curved surface has a curvature that varies at different locations on the light redirecting film.

7. The optical assembly of claim 5, wherein the curved surface and the planar or flat surface have respective areas, the respective areas having a ratio that varies at different locations on the light redirecting film.

8. The optical assembly of claim 1, wherein the individual optical elements are arranged in groupings, at least some of the optical elements in each of the groupings having a sloping surface of a different characteristic that collectively produce an average characteristic for each of the groupings that varies across the light redirecting film, wherein the characteristic of the sloping surface is selected from the following group:

depth, height, size, shape, slope angle, and length or width.

9. The assembly of claim 8, wherein the light redirecting film has a repeating pattern of the groupings.

10. The optical assembly of claim 8, wherein the individual optical elements in at least one of the groupings are randomized in slope angle, size, shape, height, depth or density.

11. An optical assembly, comprising

a light emitting assembly comprising a light emitting panel and a light source optically coupled to the light emitting panel, the light emitting panel having a light output surface that emits light at relatively low angles from the light output surface;

and

a light redirecting film located to receive the light emitted from the light output surface, the light redirecting film having a pattern of individual optical elements of well defined shape that vary in shape at different locations on the light redirecting film to redistribute the relatively low angle light received from the light output surface to relatively higher angles to suit a given application,

wherein at least one of the individual optical elements is a non-prismatic optical element having a total of two or more surfaces, at least two of the surfaces of the non-prismatic optical element intersecting a surface of the light redirecting film.

12. An optical assembly, comprising

a light emitting assembly comprising a light emitting panel and a light source optically coupled to the light emitting panel, the light emitting panel having a light output surface that emits light at relatively low angles from the light output surface;

and

a light redirecting film located to receive the light emitted from the light output surface, the light redirecting film having a pattern of individual optical elements of well defined shape that vary in shape at different locations on the light redirecting film to redistribute the relatively low angle light received from the light output surface to relatively higher angles to suit a given application,

wherein a plurality of the individual optical elements are non-prismatic optical elements, each of the non-prismatic optical elements having a total of two surfaces, the two surfaces intersecting each other.

13. The optical assembly of claim 12, wherein the two surfaces are curved surfaces.

14. The optical assembly of claim 12, wherein the individual optical elements are randomized in slope angle, size, shape, height, depth, or density.

15. The optical assembly of claim 12, wherein the individual optical elements are oriented at different angles relative to each other such that the light redirecting film redirects the light along two axes.

16. The optical assembly of claim 12, wherein one of the two surfaces is a curved surface and another of the two surfaces is a planar or flat surface.

17. The optical assembly of claim 16, wherein the curved surface has a curved surface that varies at different locations on the light redirecting film.

18. The optical assembly of claim 16, wherein the curved surface and the planar or flat surface have respective areas, the respective areas having a ratio that varies at different locations on the light redirecting film.

19. The optical assembly of claim 12, wherein the individual optical elements are arranged in groupings, at least some of the optical elements in each of the groupings having a sloping surface of a different characteristic that collectively produce an average characteristic for each of the groupings that varies across the light redirecting film, wherein the characteristic of the sloping surfaces is selected from the following group:

depth, height, size, shape, slope angle, and length or width.

20. The optical assembly of claim 19, wherein the individual optical elements in at least one of the groupings are randomized in slope angle, size, shape, height, depth or density.