Optical film and liquid crystal display

• US 9,201,267 B2
• Filed: 11/26/2013
• Issued: 12/01/2015
• Est. Priority Date: 06/20/2013
• Status: Active Grant

• Current Assignee: Tianma Microelectronics Company Limited, Xiamen Tianma Micro-Electronics Co., Ltd.
• Original Assignee: Tianma Microelectronics Company Limited, Xiamen Tianma Micro-Electronics Co., Ltd.
• Inventors: Zhuang, Xiaoling, Chen, Shichang
• Primary Examiner(s): Qi, Mike
• Application Number:
  US14/091,108
• Publication Number:
  US 20140375928A1
• Time in Patent Office: 735 Days
• Field of Search: 349/62, 349/63, 349/64, 359/625
• US Class Current: 1/1
• CPC Class Codes: G02B 27/285 comprising arrays of elements, e.g. microprisms
• CPC Class Codes: G02B 27/286 for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34
• CPC Class Codes: G02B 5/0247 by means of voids or pores
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 5/3033 in the form of a thin sheet or foil, e.g. Polaroid
• CPC Class Codes: G02B 5/3066 involving the reflection of light at a particular angle of incidence, e.g. Brewster's angle
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one

Abstract

An optical film includes a first optical layer and a second optical layer. The first optical layer is disposed above the second optical layer. The second optical layer is a composite material layer, which includes a base material and a doping layer disposed in the base material. The optical film recycles an exterior light source and improves the utilization rate of the light source.

Claims

1. An optical film, comprising a first optical layer and a second optical layer, wherein

the first optical layer is disposed under the second optical layer and comprises a prism bulging away from the second optical layer;

the second optical layer is a composite material layer comprising a base material and a doping layer in the base material.

2. The optical film according to claim 1, wherein the doping layer comprises at least one elongated bubble.

3. The optical film according to claim 2, wherein the doping layer comprises a plurality of layers formed by the at least one elongated bubble.

4. The optical film according to claim 2, wherein the bubble comprises air or CO₂.

5. The optical film according to claim 2, wherein the bubble further comprises SiO₂ particles.

6. The optical film according to claim 1, wherein the doping layer comprises at least one particle having a refractive index that is smaller than a refractive index of the first optical layer and a refractive index of the base material in the second optical layer.

7. The optical film according to claim 6, wherein the doping layer comprises a plurality of layers formed by the at least one particle.

8. The optical film according to claim 7, wherein the particle is an SiO₂ particle.

9. The optical film according to claim 1, wherein the first optical layer is a prism sheet comprising a plurality of prisms, and apex angles (vertices) of the plurality of prisms bulge outward from the outside of the optical film.

10. The optical film according to claim 9, wherein the optical film further comprises a third optical layer, third optical layer being a polarizer and disposed on the top surface of the second optical layer.

11. The optical film according to claim 10, wherein the first optical layer, the base material of the second optical layer, and the third optical layer each have a refractive index in a range from 1.3 to 1.8.

12. The optical film according to claim 9, wherein an angle of incidence α

at an apex angle (vertex) of each of the plurality of prisms is in a range of 52.2 degrees≦

α

<

90 degrees, and an apex angle (vertex) β

satisfies the relation β

=180°

−

2α

.

13. The optical film according to claim 12, wherein an angle γ

formed between intersecting sides of two adjacent prisms of the first optical layer is equal to the angle of incidence α

.

14. The optical film according to claim 1, wherein the first optical layer is a prism sheet comprising a plurality of prisms, and apex angles (vertices) of the prisms face an inner side of the optical film.

15. The optical film according to claim 14, wherein the optical film further comprises a third optical layer, is the third optical layer being a polarizer and disposed on the top surface of the second optical layer.

16. The optical film according to claim 15, wherein the first optical layer, the base material of the second optical layer, and the third optical layer each have a refractive index in a range from 1.3 to 1.8.

17. The optical film according to claim 16, wherein the doping layer in the second optical layer has a refractive index equal to or smaller than 1.2.

18. The optical film according to claim 17, wherein the optical film has a thickness equal to or greater than 0.03 mm.

19. A liquid crystal display, comprising a liquid crystal display panel, a backlight, and the optical film, the liquid crystal display panel being the outmost layer of the liquid crystal display, and the optical film being provided between the liquid crystal display panel and the backlight, the optical film comprising a first optical layer and a second optical layer, wherein

the first optical layer is disposed under the second optical layer and comprises a prism bulging away from the second optical layer,

the second optical layer is a composite material layer comprising a base material and a doping layer in the base material.