LIGHT DIRECTING FILMS

• US 20150176798A1
• Filed: 03/04/2015
• Published: 06/25/2015
• Est. Priority Date: 10/27/2011
• Status: Abandoned Application

• Current Assignee: Sergiy Victorovich Vasylyev
• Original Assignee: Sergiy Victorovich Vasylyev
• Inventors: VASYLYEV, SERGIY
• Application Number:
  US14/639,083
• Publication Number:
  US 20150176798A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B29D 11/00355 with a refractive index gradient
• CPC Class Codes: B29D 11/0073 Optical laminates
• CPC Class Codes: F21V 5/02 of prismatic shape F21V5/04 takes precedence
• CPC Class Codes: G02B 5/0236 the diffusion taking place within the volume of the element
• CPC Class Codes: G02B 5/0278 used in transmission
• 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 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer

Abstract

Light directing films employing at least two layers forming a continuous corrugated boundary between major surfaces of the film. Light received by a major surface of the film is internally redirected by interacting with the facets of the corrugated inter-layer boundary and is emitted from the opposing major surface towards a new propagation direction which is different from the original propagation direction by up to 90 degrees. Light directing films may have additional layers and/or layer boundaries which may provide additional bend angles to light rays or otherwise diffuse the emitted beam.

Claims

1. A light directing structure defined by two opposing broad-area surfaces, comprising:

a first layer of an optically transmissive material having a first refractive index;

a second layer of an optically transmissive material having a second refractive index different than the first refractive index; and

a corrugated optical interface formed between said first and second layers and characterized by a stepped change in a refractive index,

wherein said corrugated optical interface comprises a plurality of facets adjacent to each other and forming different dihedral angles between 0° and

90°

with respect to a prevailing plane of said first layer, wherein at least one of said facets is configured to redirect light by means of at least refraction or a total internal reflection.

2. A light directing structure as recited in claim 1, wherein said corrugated optical interface represents a boundary between said first and second layers.

3. A light directing structure as recited in claim 1, wherein each of said plurality of facets is planar.

4. A light directing structure as recited in claim 1, wherein at least one of said plurality of facets has a curved surface.

5. A light directing structure as recited in claim 1, wherein said corrugated optical interface comprises a repeating pattern of prismatic structures.

6. A light directing structure as recited in claim 1, wherein said plurality of facets forms a continuous prismatic pattern.

7. A light directing structure as recited in claim 1, wherein said first layer of an optically transmissive material comprises prismatic surface structures.

8. A light directing structure as recited in claim 1, wherein said corrugated optical interface comprises linear prismatic structures extending parallel to a reference line.

9. A light directing structure as recited in claim 1, wherein a surface of said first layer of an optically transmissive material is mirrored.

10. A light directing structure as recited in claim 1, wherein a surface of said first layer of an optically transmissive material is configured for an unimpeded transversal light passage.

11. A light directing structure as recited in claim 1, wherein a surface of said first layer is made attachable to a surface of an optical waveguide.

12. A light directing structure as recited in claim 1, wherein a surface of said first layer comprises a light diffusing surface texture.

13. A light directing structure as recited in claim 1, wherein outer surfaces of said first and second layers are generally smooth and transparent.

14. A light directing structure as recited in claim 1, wherein the material of one of said first and second layers is selected from low-n fluoropolymers or resins.

15. A light directing structure as recited in claim 1, wherein the lower of the two refractive indices of said first and second layers is less than 1.49.

16. A light directing structure as recited in claim 1, further comprising a third layer of an optically transmissive material adjacent to said first layer of an optically transmissive material and optically coupled to said first layer.

17. A light directing structure as recited in claim 1, wherein said first and second layers are stacked on top of another structure having a corrugated optical interface formed between layers of different refractive index materials.