Illumination articles

• US 9,823,402 B2
• Filed: 10/16/2013
• Issued: 11/21/2017
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Hao, Bing, Ender, David A., Griffin, Michael E., Anderson, Kevin W., Buccellato, Gina M., Carpenter, Barry S.
• Primary Examiner(s): Bruce, David V
• Application Number:
  US14/436,559
• Publication Number:
  US 20160170119A1
• Time in Patent Office: 1,497 Days
• CPC Class Codes: A42B 3/044 Lighting devices, e.g. helmets with lamps
• CPC Class Codes: A42B 3/0446 intended to light the way ahead
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0006 Coupling light into the fibre in general G02B6/4298
• CPC Class Codes: G02B 6/001 the light being emitted along at least a portion of the lateral surface of the fibre
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02C 11/04 Illuminating means

Abstract

Illumination articles are described. More specifically, illumination articles that include a wearable device configured for wearing on the head of a wearer, a lightguide and light sources for emitting light into the lightguide are described. The illumination articles allow for wearable devices that uniformly illuminate a working area at high brightness without providing excessive glare to observers.

Claims

1. An illumination article comprising:

a wearable device configured to wear on the head of a wearer;

a lightguide disposed on the wearable device, wherein the lightguide is elongated and has a first end and a second end opposite the first end; and

a first light source positioned at the first end, configured to emit light into the lightguide;

wherein the lightguide further comprises;

a light emitting surface extending generally in an x-direction between the first and second ends; and

a light reflecting surface positioned opposite to the light emitting surface;

wherein the light reflecting surface comprises a plurality of light extractors configured to direct light in a y-direction perpendicular to the x-direction, and

wherein the light emitting surface is configured to direct light away from the wearer and quasi-collimate the light in a direction substantially parallel to an xy-plane.

2. The illumination article of claim 1, further comprising a second light source positioned at the second end, for emitting light into the lightguide.

3. The illumination article of claim 1, wherein at least some of the light extractors in the plurality of light extractors each include an extractor light reflecting surface, and the extractor light reflecting surface in at least some of the light extractors are curved.

4. The illumination article of claim 3, wherein the extractor light reflecting surface in at least some of the light extractors is convex.

5. The illumination article of claim 3, wherein the extractor light reflecting surface in at least some of the light extractors is concave.

6. The illumination article of claim 1, wherein at least a portion of the light emitting surface has a curved yz-profile.

7. The illumination article of claim 1, wherein the light emitting surface comprises facets.

8. The illumination article of claim 1, wherein at last some of the light extractors are wedge-shaped.

9. The illumination article of claim 8, wherein the light extractors comprise wedge-shaped extractors with negative cylindrical sag.

10. The illumination article of claim 8, wherein the light extractors comprise wedge-shaped extractors with positive cylindrical sag.

11. The illumination article of claim 1, wherein at least some of the light extractors in the plurality of light extractors are configured to convert a plurality of light rays generated by the first light source into a quasi-collimated light beam.

12. The illumination article of claim 11, wherein the quasi-collimated light beam is substantially within a 20-dgree deviation from the y-direction when emitted from the light emitting surface.