Optical fiber capable of converting wavelength and backlight unit using the same

• US 10,459,167 B2
• Filed: 08/22/2018
• Issued: 10/29/2019
• Est. Priority Date: 11/24/2017
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kim, Wonrae, Lee, Seungbum, Kim, Sooin
• Primary Examiner(s): Jordan, Andrew
• Application Number:
  US16/108,228
• Publication Number:
  US 20190162905A1
• Time in Patent Office: 433 Days
• CPC Class Codes: G02B 6/0003 the light guides being doped with fluorescent agents
• CPC Class Codes: G02B 6/02 Optical fibres with cladding with or without a coating
• CPC Class Codes: G02B 6/29317 Light guides of the optical fibre type
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

The present disclosure relates to an optical fiber capable of converting a wavelength of a light emitted from a light source and a backlight unit using the same.

According to the present disclosure, it is possible to extract a light of a desired wavelength band or a desired color (for example, a white light) by connecting an optical fiber, to which a color conversion material is applied, to a single laser light emitting element that emits a light of a specific wavelength band.

Claims

1. An optical fiber, comprising:

a core portion; and

a cladding portion that covers an outer peripheral surface of the core portion;

wherein the cladding portion has a plurality of openings extending from an inside toward an outside along an extending direction of the core portion,

wherein the plurality of openings has a first crevice with which a color conversion material is filled and a second crevice with which a color conversion material is not filled,

wherein the first crevice and the second crevice are adjacent to each other.

2. The optical fiber of claim 1, wherein the color conversion material absorbs a blue light and emits a red light or a green light.

3. The optical fiber of claim 1, wherein the first crevice is filled with a material that absorbs a blue light and emits a red light, and a material that absorbs a blue light and emits a green light.

4. The optical fiber of claim 1,

wherein the opening further comprises a third crevice,

wherein the first crevice is filled with a material that absorbs a blue light and emits a red light, and

wherein the third crevice is filled with a material that absorbs a blue light and emits a green light.

5. The optical fiber of claim 1, wherein the first crevice and the second crevice are disposed in one opening and arranged along the extending direction of the core portion.

6. The optical fiber of claim 1, wherein the first crevice and the second crevice are disposed in one opening and arranged along a direction intersecting the extending direction of the core portion.

7. An optical fiber, comprising:

a core portion comprising a first core with which a color conversion material is filled and a second core with which a color conversion is not filled; and

a cladding portion that covers an outer peripheral surface of the core portion;

wherein a plurality of openings extending from an inside toward an outside is arranged along an extending direction of the first core and the second core.

8. The optical fiber of claim 7, wherein the color conversion material absorbs a blue light and emits a red light or a green light.

9. The optical fiber of claim 7, wherein the plurality of openings includes a first crevice that exposes the first core and a second crevice that exposes the second core.

10. The optical fiber of claim 9, wherein the first crevice and the second crevice expose the first core and the second core in a direction respectively oriented to each other.

11. The optical fiber of claim 10, wherein the first crevice and the second crevice have an orientation angle (θ

) determined by the following Equation 1;

Orientation angle(θ

)=arctan(2a/d)±

15°

 

 

[Equation 1]

where a is a shortest distance from a center of a first core to an outermost side of a cladding or a shortest distance from a center of a second core to an outermost side of a cladding, and

d is a shortest distance between a center of a first core and a center of a second core.

12. The optical fiber of claim 7, wherein the first core includes a material that absorbs a blue light and emits a red light, and a material that absorbs a blue light and emits a green light.

13. The optical fiber of claim 7,

wherein the core portion further comprises a third core portion,

wherein the plurality of openings further comprises a third crevice to exposes a third core,

wherein the first core portion is filled with a material that absorbs a blue light and emits a red light, and

wherein the third core portion is filled with a material that absorbs a blue light and emits a green light.

14. A backlight unit, comprising:

a light source that emits light having a single wavelength; and

an optical fiber that converts the single wavelength of the light emitted from the light source and emits the converted light;

wherein the optical fiber includes;

a core portion where the light emitted from the light source proceeds; and

a cladding portion that covers an outer peripheral surface of the core portion;

wherein the cladding portion is arranged with a plurality of openings extending from an inside toward an outside along an extending direction of the core portion,

wherein the plurality of openings includes a first crevice with which a color conversion material is filled and a second crevice with which a color conversion material is not filled, and

wherein the first crevice and the second crevice are adjacent to each other.

15. The backlight unit of claim 14, wherein the light source emits a blue light.

16. The backlight unit of claim 14, wherein the color conversion material is a material that absorbs a blue light and emits a red light or a green light.

17. The backlight unit of claim 14, wherein the first crevice includes a material that absorbs a blue light and emits a red light, and a material that absorbs a blue light and emits a green light.

18. A backlight unit, comprising:

a light source that emits light having a single wavelength; and

an optical fiber that converts the single wavelength of the light emitted from the light source and emits the converted light;

wherein the optical fiber includes;

a core portion that includes a color conversion material, and where the light emitted from the light source proceeds; and

a cladding portion that covers an outer peripheral surface of the core portion;

wherein the cladding portion is arranged with a plurality of openings extending from an inside toward an outside along an extending direction of the core portion.

19. The backlight unit of claim 18, wherein the light source emits a blue light.

20. The backlight unit of claim 18,

wherein the core portion includes a first core with which the color conversion material is filled and a second core with which the color conversion material is not filled, and

wherein the plurality of openings includes a first crevice that exposes the first core and a second crevice that exposes the second core.

21. The backlight unit of claim 18, wherein the first core is filled with a material that absorbs a blue light and emits a red light, and a material that absorbs a blue light and emits a green light.