Light guide with protective outer sleeve

• US 6,621,973 B1
• Filed: 03/16/2000
• Issued: 09/16/2003
• Est. Priority Date: 03/16/2000
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Hoffman, Joseph Andrew
• Primary Examiner(s): Ullah, Akm Enayet
• Assistant Examiner(s): Rahll, Jerry T
• Application Number:
  US09/526,609
• Time in Patent Office: 1,279 Days
• Field of Search: 385/133, 385/123, 385/36, 385/125
• US Class Current: 385/133
• CPC Class Codes: F21V 2200/40 of hollow light guides
• CPC Class Codes: G02B 6/0096 the lights guides being of the hollow type

Abstract

An illumination device including a light guide 22 surrounded by a protective sleeve 24. The light guide 22 is hollow and includes a cylindrical wall 26 having a structured outer surface 28 and a smooth inner surface 30. Light release structures are provided to reflect or refract light through the cylindrical wall 26 of the light guide 22. In certain embodiments, the protective sleeve is bonded to the light guide. Rigid fixtures can be used to retain the light guide in elastically deformed, non-cylindrical cross-sectional shapes.

Claims

1. A light conveying device comprising:

a hollow light guide including a wall having a generally smooth inner side and a structured outer side, the structured outer side including a plurality of prisms defining grooves that extend along a length of the light guide; and

a protective outer sleeve bonded to the structured outer side of the light guide at three or more locations spaced about a perimeter of the light guide.

2. The light conveying device of claim 1, further comprising a light release structure provided adjacent at least one of the inner and outer sides of the light guide for causing light to be released from the light guide through the wall of the light guide.

3. The light conveying device of claim 2, wherein the light release structure comprises a plurality of light releasing dots.

4. The light conveying device of claim 2, wherein the light release structure comprises a plurality of light releasing lines.

5. The light conveying device of claim 2, wherein the light release structure includes a plurality of light releasing structures printed on the light guide.

6. The light conveying device of claim 1, wherein the outer sleeve is bonded to the light guide by adhesive.

7. The light conveying device of claim 6, wherein the adhesive provides light extraction from the light guide.

8. The light conveying device of claim 1, wherein the wall of the light guide is formed by flexible optical film, and the outer sleeve comprises a flexible polymeric layer.

9. The light conveying device of claim 1, wherein the outer sleeve is transparent.

10. The light conveying device of claim 1, wherein the outer sleeve has a matte finish.

11. The light conveying device of claim 1, wherein the outer sleeve includes a reflective material.

12. The light conveying device of claim 11, wherein the reflective material comprises a pattern of reflective material printed on the outer sleeve.

13. The light conveying device of claim 11, wherein the reflective material comprises a plurality of dots.

14. The light conveying device of claim 1, wherein the outer sleeve includes a translucent material.

15. The light conveying device of claim 1, wherein a majority of the prisms are bonded to the outer sleeve.

16. The light conveying device of claim 1, wherein the light conveying device includes an alignment structure for rotationally aligning the light conveying device.

17. The light conveying device of claim 16, wherein the alignment structure comprises a projection that projects axially from at least one of the light guide and the sleeve.

18. The light conveying device of claim 16, wherein the alignment structure comprises an end notch defined by at least one of the light guide and the sleeve.

19. The light conveying device of claim 1, wherein substantially all of the prisms are bonded to the outer sleeve.

20. A light distribution system comprising:

a flexible hollow light guide including a wall having a generally smooth inner side and a structured outer side, the structured outer side including a plurality of prisms defining grooves that extend along a length of the light guide;

a flexible protective outer sleeve surrounding the structured outer side of the light guide;

a light release structure provided adjacent at least one of the inner and outer sides of the light guide for causing light to be released from the light guide through the wall of the light guide; and

a fixture having a generally non-cylindrical portion that surrounds the light guide for retaining the hollow light guide in an elastically deformed, generally non-cylindrical configuration, wherein the outer sleeve prevents the structured outer side of the light guide from contacting the fixture.

21. The system of claim 20, wherein the outer sleeve is bonded to the light guide.

22. The system of claim 21, wherein the outer sleeve is bonded to the light guide by adhesive.

23. The system of claim 21, wherein the outer sleeve is bonded to the light guide at least several circumferentially spaced-apart locations.

24. The system of claim 21, wherein a majority of the prisms are bonded to the outer sleeve.

25. The system of claim 24, wherein substantially all of the prisms are bonded to the outer sleeve.

26. The system of claim 20, wherein the wall of the light guide is formed by flexible optical film, and the outer sleeve comprises a flexible polymeric layer.

27. The system of claim 20, wherein the outer sleeve is transparent.

28. The system of claim 20, wherein the outer sleeve has a matte finish.

29. The system of claim 20, wherein the outer sleeve includes a reflective material.

30. The system of claim 29, wherein the reflective material comprises a pattern of reflective material printed on the outer sleeve.

31. The system of claim 29, wherein the reflective material comprises a plurality of dots.

32. The light conveying device of claim 20, wherein the outer sleeve includes a translucent material.

33. The light conveying device of claim 20, wherein the fixture retains the light guide in a generally square cross-sectional configuration.

34. The light conveying device of claim 20, wherein the fixture retains the light guide in a generally rectangular cross-sectional configuration.

35. The light conveying device of claim 20, wherein the fixture retains the light guide in a generally triangular cross-sectional configuration.

36. The light conveying device of claim 20, wherein the fixture retains the light guide in a generally dome-shaped cross-sectional configuration.

37. The system of claim 20, wherein the light guide assumes a generally cylindrical configuration when removed from the fixture.

38. A light conveying device comprising:

an optical film having a generally smooth first side and a structured second side, the structured second side including a plurality or prisms defining a plurality of parallel grooves;

a flexibly protective layer bonded to at least several of the prisms of the optical film; and

wherein the protective layer is bonded to the prisms by adhesive.

39. The light conveying device of claim 38, wherein a majority of the prisms are bonded to the protective layer.

40. The light conveying device of claim 39, wherein substantially all of the prisms are bonded to the protective layer.

41. The light conveying device of claim 38, wherein the protective layer comprises a flexible polymeric sheet.

42. A light distribution system comprising:

a flexible hollow light guide comprising at least one sheet of optical film, the hollow light guide including a wall having a generally smooth inner side and a structured outer side, the structured outer side including a plurality of prisms defining grooves that extend along a length of the light guide;

a light release structure provided adjacent at least one of the inner and outer sides of the light guide for causing light to be released from the light guide through the wall of the light guide; and

a rigid fixture including a retaining portion for retaining the light guide in an elastically deformed state, the retaining portion including at least two separate pieces that when joined together function to compress the light guide into a non-cylindrical configuration.

43. The light distribution system of claim 42, wherein the two separate pieces are symmetrical.

44. The light distribution system of claim 42, further comprising a protective sleeve positioned between the light guide and the fixture.

45. A light distribution system comprising:

a flexible hollow light guide comprising at least one sheet of optical film, the hollow light guide including a wall having a generally smooth inner side and a structured outer side, the structured outer side including a plurality of prisms defining grooves that extend along a length of the light guide;

a light release structure provided adjacent at least one of the inner and outer sides of the light guide for causing light to be released from the light guide through the wall of the light guide; and

a rigid fixture including a retaining portion for retaining the light guide in an elastically deformed state, the retaining portion including at least one planar wall and at least one curved wall, the light guide including at least a first portion that is elastically deformed in conformance with a curvature of the curved wall.

46. The light distribution system of claim 45, wherein the light guide comprises a single continuous sheet of optical film.

47. The light distribution system of claim 45, wherein the light guide includes a second portion that conforms to at least part of the planar wall.

48. The light distribution system of claim 45, further comprising a protective sleeve positioned between the light guide and the fixture.

49. A light distribution system comprising:

a flexible hollow light guide comprising at least one sheet of optical film, the hollow light guide including a wall having a generally smooth inner side and a structured outer side, the structured outer side including a plurality of prisms defining grooves that extend along a length of the light guide, the light guide having a tubular configuration when not deformed;

a light release structure provided adjacent at least one of the inner and outer sides of the light guide for causing light to be released from the light guide through the wall of the light guide; and

a rigid fixture including a retaining portion for retaining the light guide in an elastically deformed state, the rigid fixture having a shape selected from the group consisting of a generally square cross-sectional shape, a generally rectangular cross-sectional shape, a generally triangular cross-sectional shape, a generally oval cross-sectional shape and a generally dome-shaped cross-sectional shape.

50. The light distribution system of claim 49, wherein the light guide comprises a single continuous sheet of optical film.

51. The light distribution system of claim 50, wherein the retaining portion of the fixture has a generally triangular cross-sectional shape.

52. The light distribution system of claim 50, wherein the retaining portion of the fixture has a generally square cross-sectional shape.

53. The light distribution system of claim 49, wherein the retaining portion of the fixture includes a curved wall, and the light guide includes a third portion that is elastically deformed in conformance with a curvature of the curved wall.

54. The light distribution system of claim 50, wherein the retaining portion of the fixture has a generally rectangular cross-sectional shape.

55. The light distribution system of claim 49, wherein the retaining portion of the fixture has a generally oval shaped cross-section.

56. The light distribution system of claim 49, wherein the retaining portion of the fixture has a generally dome-shaped cross-section.

57. The light distribution system of claim 49, further comprising a protective sleeve positioned between the light guide and the fixture.