Color shift sign

Patent metadata

Field	Value
Publication number	US-9404637-B2
Application number	US-201214364248-A
Country	US
Kind code	B2
Filing date	Dec 7, 2012
Priority date	Dec 19, 2011
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

The present application is directed to an illumination device comprising a recycling cavity defined by recycling surfaces and a light emission surface; a light source within the cavity. A spectrum modifying layer is on a portion of the recycling surface, the spectrum modifying layer producing a spectral response different from the spectral response of the recycling surface. In some embodiments, the spectrum modifying layer shifts the spectral properties of the light being emitted from the light emission area from the spectral properties of the light source. In some embodiments, the spectrum modifying layer selectively absorbs a portion of light along the light source spectrum. In some embodiments, the spectrum modifying layer re-emits light at a wavelength longer than the wavelength it absorbed.

First claim

What is claimed is:

1. An illumination device comprising
a recycling cavity defined by recycling surfaces and a light emission surface, wherein the light emission surface is a partial mirror;
a light source within the cavity; and
a spectrum modifying layer on a portion of the recycling surface, the spectrum modifying layer producing a spectral response different from the spectral response of the recycling surface, and wherein the spectrum modifying layer is a phosphorescent material.

2. The device of claim 1 wherein the spectrum modifying layer shifts the spectral properties of the light being emitted from the light emission area from the spectral properties of the light source.

3. The device of claim 1 wherein the spectrum modifying layer selectively absorbs a portion of light along the light source spectrum.

4. The device of claim 3 wherein the spectrum modifying layer re-emits light at a wavelength longer than the wavelength it absorbed.

5. The device of claim 4 wherein the spectrum modifying layer is a fluorescent material.

6. The device of claim 3 wherein the spectrum modifying layer is a colored layer.

7. The device of claim 3 wherein the spectrum modifying layer absorbs wavelengths below 550 nm.

8. The device of claim 3 wherein the spectrum modifying layer absorbs wavelengths above 600 nm.

9. The device of claim 1 wherein the spectrum modifying layer is an ink layer.

10. The device of claim 1 wherein the spectrum modifying layer is a tape.

11. The device of claim 1 wherein the spectrum modifying layer is a film.

12. The device of claim 1 wherein the light emission surface is a diffuser.

13. The device of claim 1 wherein the light emission surface is a microreplicated sheet.

14. The device of claim 1 wherein the light source is an LED.

15. The device of claim 1 wherein the light source is a fluorescent bulb.

16. The device of claim 1 wherein the light source is an OLED.

17. The device of claim 1 wherein the light source is an electroluminescent layer.

18. An illumination device comprising
a recycling cavity defined by recycling surfaces and a light emission surface;
a light source within the cavity; and
a spectrum modifying layer on a portion of the recycling surface, the spectrum modifying layer producing a spectral response different from the spectral response of the recycling surface, and wherein the light emission surface is a partial mirror.

19. The device of claim 18 wherein the spectrum modifying layer selectively absorbs a portion of light along the light source spectrum.

20. The device of claim 18 wherein the spectrum modifying layer shifts the spectral properties of the light being emitted from the light emission area from the spectral properties of the light source.

21. The device of claim 20 wherein the spectrum modifying layer re-emits light at a wavelength longer than the wavelength it absorbed.

22. The device of claim 21 wherein the spectrum modifying layer is a fluorescent material.

23. The device of claim 18 wherein the spectrum modifying layer is a colored layer.

24. The device of claim 21 wherein the spectrum modifying layer absorbs wavelengths below 550 nm.

25. The device of claim 18 wherein the spectrum modifying layer absorbs wavelengths above 600 nm.

Assignees

• 3M Innovative Properties Co

Inventors

• Aeling Ellen O
• Meis Michael A
• Simpson John T
• Hoffman Joseph A
• Humpal Paul E

Classifications

• F21V9/45

  by adjustment of photoluminescent elements · CPC title

• F21V9/40

  with provision for controlling spectral properties, e.g. colour, or intensity · CPC title

• G09F13/04

  Signs, boards or panels, illuminated from behind the insignia · CPC title

• F21Y2115/15

  Organic light-emitting diodes [OLED] · CPC title

• F21Y2103/00

  Elongate light sources, e.g. fluorescent tubes · CPC title