Display device comprising an illumination device having a light diffusion layer exhibiting a first diffusion degree in a first direction which is different than a second diffusion degree in a second direction

Patent metadata

Field	Value
Publication number	US-11249343-B2
Application number	US-202117181148-A
Country	US
Kind code	B2
Filing date	Feb 22, 2021
Priority date	Nov 14, 2016
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

A display device is provided and includes display panel; and illumination device opposed to display panel, illumination device including first light guide, second light guide arranged adjacent to first light guide in first direction, third light guide arranged adjacent to first light guide in second direction intersecting first direction, and fourth light guide arranged adjacent to second light guide in the second direction, light diffusion layer disposed between display panel and each of the first, second, third, and fourth light guides, wherein light diffusion layer exhibit first diffusion degree in first direction and second diffusion degree in second direction, second diffusion degree is different from the first diffusion degree, illumination device includes first ridge between first and second light guides and second ridge between first and third light guides, and under light diffusion layer, first brightness in first ridge is different from second brightness in second ridge.

First claim

What is claimed is:

1. A display device comprising:
a display panel; and
an illumination device opposed to the display panel so as to illuminates the display panel,
the illumination device comprising:
a first light guide,
a second light guide arranged adjacent to the first light guide in a first direction,
a third light guide arranged adjacent to the first light guide in a second direction intersecting the first direction, and
a fourth light guide arranged adjacent to the second light guide in the second direction,
a light diffusion layer disposed between the display panel and each of the first light guide, the second light guide, the third light guide, and the fourth light guide, wherein
the light diffusion layer exhibit a first diffusion degree in the first direction and a second diffusion degree in the second direction,
the second diffusion degree is different from the first diffusion degree,
the illumination device comprises a first ridge between the first light guide and the second light guide and a second ridge between the first light guide and the third light guide, and
under the light diffusion layer, a first brightness in the first ridge is different from a second brightness in the second ridge.

2. The display device of claim 1 , wherein
the first brightness is lower than the second brightness, and
the first diffusion degree is higher than the second diffusion degree.

3. The display device of claim 2 , wherein
the first brightness is lower than a reference brightness, and
the second brightness is higher than the reference brightness.

4. The display device of claim 1 , wherein
the first brightness is higher than the second brightness, and
the first diffusion degree is lower than the second diffusion degree.

5. The display device of claim 4 , wherein,
the first brightness is higher than a reference brightness, and
the second brightness is lower than the reference brightness.

6. The display device of claim 1 , wherein
the first brightness is higher than the second brightness,
the second brightness is higher than a reference brightness, and
the first diffusion degree is higher than the second diffusion degree.

7. The display device of claim 1 , wherein
the second brightness is higher than the first brightness,
the first brightness is higher than a reference brightness, and
the second diffusion degree is higher than the first diffusion degree.

8. The display device of claim 1 , wherein
the second brightness is lower than the first brightness,
the first brightness is lower than a reference brightness, and
the second diffusion degree is higher than the first diffusion degree.

9. The display device of claim 1 , wherein
the first brightness is lower than the second brightness,
the second brightness is lower than a reference brightness, and
the first diffusion degree is higher than the second diffusion degree.

10. The display device of claim 3 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

11. The display device of claim 5 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

12. The display device of claim 6 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

13. The display device of claim 7 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

14. The display device of claim 8 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

15. The display device of claim 9 , wherein
a first length of the first ridge is shorter than a second length of the second ridge.

16. The display device of claim 1 , further comprising;
a first light source being surrounded by the first light guide,
a second light source being surrounded by the second light guide,
a third light source being surrounded by the third light guide, and
a fourth light source being surrounded by the fourth light guide.

17. The display device of claim 3 , further comprising;
a first light source being surrounded by the first light guide,
a second light source being surrounded by the second light guide,
a third light source being surrounded by the third light guide, and
a fourth light source being surrounded by the fourth light guide.

18. The display device of claim 5 , further comprising;
a first light source being surrounded by the first light guide,
a second light source being surrounded by the second light guide,
a third light source being surrounded by the third light guide, and
a fourth light source being surrounded by the fourth light guide.

19. The display device of claim 6 , further comprising;
a first light source being surrounded by the first light guide,
a second light source being surrounded by the second light guide,
a third light source being surrounded by the third light guide, and
a fourth light source being surrounded by the fourth light guide.

20. The display device of claim 7 , further comprising;
a first light source being surrounded by the first light guide,
a second light source being surrounded by the second light guide,
a third light source being surrounded by the third light guide, and
a fourth light source being surrounded by the fourth light guide.

21. The display device of claim 1 , further comprising;
a controller which computes a brightness profile and controls a transmissivity of the display panel,
wherein
the controller corrects the transmissivity at position overlapping the second ridge based on the brightness profile.

Assignees

• Japan Display Inc

Inventors

• Yata Tatsuya
• Aoki Shigenori

Classifications

• G02F1/133603 Primary

  with LEDs · CPC title

• G02F1/133602

  Direct backlight · CPC title

• G02F1/133605

  including specially adapted reflectors · CPC title

• G02B6/0068

  Arrangements of plural sources, e.g. multi-colour light sources · CPC title

• G02F1/133606 Primary

  including a specially adapted diffusing, scattering or light controlling members · CPC title