High brightness phosphorescent panel

• US 7,153,593 B1
• Filed: 04/24/2003
• Issued: 12/26/2006
• Est. Priority Date: 04/24/2002
• Status: Expired due to Fees

• Current Assignee: Cleveland C. Smith
• Original Assignee: Cleveland C. Smith
• Inventors: Waterbury, Mark C
• Primary Examiner(s): Dye, Rena
• Assistant Examiner(s): Thompson, Camie S
• Application Number:
  US10/423,632
• Time in Patent Office: 1,342 Days
• Field of Search: 428/690, 428/917, 428/332, 428/913, 252/301.36, 350/105, 350/484.4, 405/42, 405/43, 250/404.6, 429/917
• US Class Current: 428/690
• CPC Class Codes: G09F 13/20 with luminescent surfaces or parts luminescent compositions C09K11/00; light sources using luminescence F21K2/00
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

The invention describes an article of manufacture that comprises an optimized phosphorescent laminate structure that produces much brighter light than previously disclosed phosphorescent laminates or coatings by enabling and capturing multiple emissions and reflections of light emitted by phosphorescent particles that are distributed through the thickness of a transparent layer. These multiple emissions are enabled by providing a transparent carrier layer that is many times as thick as the phosphorescent powder particle size. That layer is loaded with an amount of phosphorescent powder that is low enough to allow light emitted by the deeper layers of powder to escape, but high enough to provide a very large amount of emitting powder. This structure may be protected by surface films and backed by a reflective layer for efficient unidirectional light absorption and emission.

Claims

1. A luminous panel, comprising:

a transparent layer with thickness between about 1 millimeter and about 3 millimeters; and

phosphorescent powder incorporated in said transparent layer in an amount between about 8 volume percent and about 15 volume percent of said transparent layer;

whereby a high brightness, bidirectional phosphorescent panel is obtained.

3. The luminous panel of claim 1, further comprising:

a first protective polymer film layer, comprising;

a flexible film layer about 25 to 50 microns in thickness; and

a moisture and oxygen barrier coating on said film layer; and

a second protective polymer film layer, comprising;

a flexible film layer about 25 to 50 microns in thickness; and

a moisture and oxygen barrier coating on said film layer;

whereby said phosphorescent powder in said transparent layer is protected from exposure to moisture and oxygen.

5. The luminous panel of claim 3, further comprising:

a protective polymer film layer comprising an ultraviolet light rejecting layer.

7. The luminous panel of claim 3, wherein each of said protective polymer film layers further comprises:

an adhesion promotion layer, comprising;

a surface treatment applied to said polymer film layer; and

a transparent adhesive binder coating on said flexible film layer.

2. A luminous panel comprising:

a transparent layer with thickness between about 750 microns and about 2,000 microns;

phosphorescent powder incorporated in said transparent layer in an amount between about 8 volume percent and about 15 volume percent of said transparent layer; and

a reflective backing layer contiguous to said transparent layer;

whereby a high brightness, unidirectional phosphorescent panel is obtained.

4. The luminous panel of claim 2, further comprising:

a first protective polymer film layer, comprising;

a flexible film layer about 25 to 50 microns in thickness; and

a moisture and oxygen barrier coating on said film layer; and

a second protective polymer film layer, comprising;

a flexible film layer about 25 to 50 microns in thickness; and

a moisture and oxygen barrier coating on said film layer;

whereby the phosphorescent powder in said transparent layer is protected from exposure to moisture and oxygen.

6. The luminous panel of claim 4, further comprising:

a protective polymer film layer comprising an ultraviolet light rejecting layer.

8. The luminous panel of claim 4, wherein each of said protective polymer film layers further comprises:

an adhesion promotion layer comprising;

a surface treatment applied to said polymer film layer; and

a transparent adhesive binder coating on said flexible film layer.

9. A luminous panel, comprising:

a phosphorescent powder having a predetermined particle size; and

a layer of light-transmitting material having said phosphorescent powder embedded therein, said layer of light-transmitting material having a thickness which is multiple times greater than said particle size of said phosphorescent powder;

said phosphorescent powder being distributed in said light-transmitting material, in a concentration of about 15 volume percent or less and in an amount greater than would form a single particle-thick layer on a surface of said layer of light-transmitting material.

10. The luminous panel of claim 9, wherein said light transmitting material is substantially transparent.

11. The luminous panel of claim 9, wherein said light transmitting material is substantially translucent.

12. The luminous panel of claim 9, wherein said phosphorescent powder is distributed in said layer of light transmitting material to a depth greater than about 30 times said particle size of said phosphorescent powder.

13. The luminous panel of claim 12, wherein said depth to which said phosphorescent powder is distributed in said layer of light transmitting material is in the range from about 50 to about 200 times said particle size of said phosphorescent powder.

14. The luminous panel of claim 13, wherein said concentration of said phosphorescent powder is in the range from about 8 volume percent to about 15 volume percent of said light transmitting material.

15. The luminous panel of claim 13, wherein said concentration of said phosphorescent powder is about 10 volume percent of said light transmitting material.

16. The luminous panel of claim 9, further comprising:

a reflective layer mounted on a side of said layer of light transmitting material opposite said surface thereof so as to reflect light radiated by said powder back through said layer of light transmitting material towards said surface thereof.

17. The luminous panel of claim 9, further comprising:

a layer of substantially transparent, UV-rejecting material mounted over said surface so as to protect said layer of light transmitting material and said phosphorescent powder embedded therein.

18. The luminous panel of claim 9, further comprising:

a layer of substantially transparent, oxygen and moisture excluding material mounted over said surface so as to protect said layer of light transmitting material and said phosphorescent powder embedded therein.