Optical member and display device including the same

• US 10,371,881 B2
• Filed: 08/24/2018
• Issued: 08/06/2019
• Est. Priority Date: 09/08/2017
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Hwang, Seong Yong, Park, Young Min, Yoon, Ju Young, Shim, Sung Kyu, Lee, Sang Won
• Primary Examiner(s): Raleigh, Donald L
• Application Number:
  US16/111,215
• Publication Number:
  US 20190079240A1
• Time in Patent Office: 347 Days
• CPC Class Codes: G02B 6/0035 provided on the surface of the light guide or in the bulk of it
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0093 Means for protecting the light guide

Abstract

An optical member including a light guide plate including a surface disposed on a plane defined by a first direction and a second direction crossing the first direction, a low refractive index pattern disposed on the surface of the light guide plate and including an opening for exposing the surface of the light guide plate, a wavelength conversion layer disposed on the low refractive index pattern, and a passivation layer disposed on the wavelength conversion layer and covering a side surface of the wavelength conversion layer and a side surface of the low refractive index pattern at least one side portion. The low refractive index pattern has a lower index of refraction than the light guide plate, and a ratio of an area occupied by the low refractive index pattern to an area of the surface of the light guide plate decreases in the first direction.

Claims

1. An optical member comprising:

a light guide plate including a surface disposed on a plane defined by a first direction and a second direction crossing the first direction;

a low refractive index pattern disposed on the surface of the light guide plate and including an opening for exposing the surface of the light guide plate;

a wavelength conversion layer disposed on the low refractive index pattern; and

a passivation layer disposed on the wavelength conversion layer and configured to cover a side surface of the wavelength conversion layer and a side surface of the low refractive index pattern at at least one side portion,

wherein;

the low refractive index pattern has a lower index of refraction than the light guide plate; and

a ratio of an area occupied by the low refractive index pattern to an area of the surface of the light guide plate decreases in the first direction.

2. The optical member of claim 1, wherein the surface of the light guide plate exposed by the opening is in contact with the wavelength conversion layer.

3. The optical member of claim 2, wherein the opening is a through hole configured to pass through the low refractive index pattern in a third direction perpendicular to the plane.

4. The optical member of claim 3, wherein the through hole comprises a plurality of through holes having a certain planar area in the first direction and the second direction.

5. The optical member of claim 4, wherein the plurality of through holes have an arrangement density gradually increasing in the first direction.

6. The optical member of claim 4, wherein the through hole comprises a plurality of through holes having a planar area gradually increasing in the first direction.

7. The optical member of claim 6, wherein the wavelength conversion layer has an area in contact with the surface of the light guide plate, and the area gradually increases in the first direction.

8. The optical member of claim 2, wherein the low refractive index pattern is composed of a plurality of low refractive index patterns spaced apart from each other to form the opening.

9. The optical member of claim 8, wherein each of the plurality of low refractive index patterns has a planar area gradually decreasing in the first direction.

10. The optical member of claim 9, wherein the wavelength conversion layer has an area in contact with the surface of the light guide plate, and the area gradually increases in the first direction.

11. The optical member of claim 1, wherein the light guide plate comprises an inorganic material.

12. The optical member of claim 11, wherein a difference between a refractive index of the light guide plate and a refractive index of the low refractive index pattern is 0.2 or more.

13. The optical member of claim 12, wherein the wavelength conversion layer has a higher refractive index than the low refractive index pattern.

14. An optical member comprising:

a light guide plate including a surface, a first side surface crossing the surface, and a second surface opposite the first side surface;

a low refractive index pattern disposed on the surface of the light guide plate and comprising an opening for exposing the surface of the light guide plate;

a wavelength conversion layer disposed on the low refractive index pattern; and

a passivation layer disposed on the wavelength conversion layer and covering a side surface of the wavelength conversion layer and a side surface of the low refractive index pattern at at least one side portion,

wherein;

the low refractive index pattern has a lower index of refraction than the light guide plate; and

a ratio of an area occupied by the low refractive index pattern to an area of the surface of the light guide plate decreases in a direction away from the first side surface.

15. The optical member of claim 14, wherein the ratio of the area occupied by the low refractive index pattern to an area of the surface of the light guide plate decreases in a direction away from the second side surface.

16. The optical member of claim 15, wherein the surface of the light guide plate exposed by the opening is in contact with the wavelength conversion layer.

17. The optical member of claim 16, wherein the wavelength conversion layer has a higher refractive index than the low refractive index pattern.

18. A display device comprising:

an optical member comprising,

a light guide plate including a light incidence surface,

a low refractive index layer disposed on the light guide plate and having a lower index of refraction than the light guide plate,

a wavelength conversion layer disposed on the low refractive index layer, and

a passivation layer disposed on the wavelength conversion layer and covering a side surface of the wavelength conversion layer and a side surface of the low refractive index layer at at least one side portion;

a light source disposed at a side of the light incidence surface of the light guide plate; and

a display panel disposed on the optical member,

wherein the low refractive index layer comprises patterns, and an area in which the low refractive index layer is disposed decreases in a direction away from the light incidence surface.

19. The display device of claim 18, further comprising a reflective member disposed under the optical member,

wherein the wavelength conversion layer is disposed between the light guide plate and the display panel.

20. The display device of claim 18, further comprising a reflective member disposed under the optical member,

wherein the wavelength conversion layer is disposed between the light guide plate and the reflective member.