DISPLAY DEVICE, ELECTRONIC DEVICE, AND MOBILE INFORMATION TERMINAL

• US 20200133064A1
• Filed: 12/24/2019
• Published: 04/30/2020
• Est. Priority Date: 08/17/2016
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei, SEO, Satoshi, HATSUMI, Ryo
• Granted Patent: US 11,300,826 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/1343 Electrodes reflective electrodes G02F1/133553
• CPC Class Codes: G02F 1/13718 based on a change of the texture state of a cholesteric liquid crystal
• CPC Class Codes: G02F 2201/44 Arrangements combining different electro-active layers, e.g. electrochromic, liquid crystal or electroluminescent layers
• CPC Class Codes: H04N 1/6058 Reduction of colour to a range of reproducible colours, e.g. to ink- reproducible colour gamut
• CPC Class Codes: H04N 1/6066 dependent on the gamut of the image to be reproduced
• CPC Class Codes: H10K 50/13 comprising stacked EL layers within one EL unit
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/50 OLEDs integrated with light modulating elements, e.g. with electrochromic elements, photochromic elements or liquid crystal elements

Abstract

A display device capable of displaying images with wide color gamut is provided. A display device capable of displaying images with wide color gamut and capable of relaxing contrast made by narrow spectra is provided. The display device includes a liquid crystal element and a light-emitting element. Light obtained from the liquid crystal element through a color filter has an NTSC area ratio of more than or equal to 20 percent and less than or equal to 60 percent and light emitted by the light-emitting element has a BT.2020 area ratio of more than or equal to 80 percent and less than or equal to 100 percent.

Claims

1. A display device comprising:

a liquid crystal element; and

a first light-emitting element,

wherein light obtained from the liquid crystal element has an NTSC coverage of more than or equal to 20% and less than or equal to 60%,

wherein light emitted by the first light-emitting element has CIE 1931 chromaticity coordinates (x1, y1), and

wherein y1 is more than 0.710 and less than or equal to 0.810.

2. The display device according to claim 1, wherein the liquid crystal element overlaps with the first light-emitting element.

3. The display device according to claim 1,

wherein the liquid crystal element is a reflective liquid crystal element, and

wherein the first light-emitting element comprises an EL layer between a reflective electrode and a semi-transmissive and semi-reflective electrode.

4. The display device according to claim 1, further comprising,

a second light-emitting element,

wherein light emitted by the second light-emitting element has CIE 1931 chromaticity coordinates (x2, y2),

wherein x2 is more than 0.680 and less than or equal to 0.720, and

wherein y2 is more than or equal to 0.260 and less than or equal to 0.320.

5. The display device according to claim 4, wherein the liquid crystal element overlaps with the second light-emitting element.

6. The display device according to claim 1, further comprising a third light-emitting element,

wherein light emitted by the third light-emitting element has CIE 1931 chromaticity coordinates (x3, y3),

wherein x3 is more than or equal to 0.120 and less than or equal to 0.170, and

wherein y3 is more than or equal to 0.020 and less than 0.060.

7. The display device according to claim 6, wherein the liquid crystal element overlaps the third light-emitting element.

8. The display device according to claim 1, wherein x1 is more than or equal to 0.130 and less than or equal to 0.250.

9. The display device according to claim 1,

wherein the liquid crystal element comprises a reflective electrode, a liquid crystal layer and a color filter,

wherein the first light-emitting element comprises a pair of electrodes and a first light-emitting layer between the pair of electrodes, and the color filter,

wherein the liquid crystal element is configured to reflect outside light through the color filter,

wherein the first light-emitting element is configured to make light emitted from the first light-emitting layer pass through the color filter, and

wherein a reflectance of the liquid crystal element through the color filter is more than or equal to 16% and less than or equal to 26%.

10. The display device according to claim 9, wherein a driving mode for the liquid crystal element is an electrically controlled birefringence mode.

11. The display device according to claim 9, wherein the liquid crystal layer is positioned between the first light-emitting layer and the color filter.

12. The display device according to claim 1, wherein the display device is a head-mounted display.

13. A display device comprising:

a liquid crystal element; and

a light-emitting element comprising;

a first light-emitting element;

a second light-emitting element; and

a third light-emitting element,

wherein light obtained from the liquid crystal element has an NTSC coverage of more than or equal to 20% and less than or equal to 60%,

wherein light emitted by the first light-emitting element has CIE 1931 chromaticity coordinates (x1, y1),

wherein light emitted by the first light-emitting element has CIE 1931 chromaticity coordinates (x2, y2),

wherein light emitted by the first light-emitting element has CIE 1931 chromaticity coordinates (x3, y3),

wherein y1 is more than 0.710 and less than or equal to 0.810,

wherein x2 is more than 0.680 and less than or equal to 0.720, and

wherein y3 is more than or equal to 0.020 and less than 0.060.

14. The display device according to claim 13,

wherein the first light-emitting element is configured to emit green light,

wherein the second light-emitting element is configured to emit red light, and

wherein the third light-emitting element is configured to emit blue light.

15. The display device according to claim 13,

wherein the liquid crystal element comprises a reflective electrode, a liquid crystal layer and a color filter,

wherein each of the first light-emitting element, the second light-emitting element, the third light-emitting element comprises a pair of electrodes and a light-emitting layer between the pair of electrodes, and the color filter,

wherein the liquid crystal element is configured to reflect outside light through the color filter,

wherein the first light-emitting element is configured to make light emitted from the light-emitting layer pass through the color filter, and

wherein the liquid crystal layer and the light-emitting layer overlap each other.

16. The display device according to claim 15, wherein a reflectance of the liquid crystal element through the color filter is more than or equal to 16% and less than or equal to 26%.

17. The display device according to claim 15, wherein a driving mode for the liquid crystal element is an electrically controlled birefringence mode.

18. The display device according to claim 15, wherein the liquid crystal layer is positioned between the color filter and the light-emitting layer of the first light-emitting element.

19. The display device according to claim 13, further comprising a fourth light-emitting element,

wherein lights emitted from the first light-emitting element, the second light-emitting element, the third light-emitting element and the fourth light-emitting element are different from each other.

20. The display device according to claim 19, wherein the fourth light-emitting element is configured to emit white light.

21. The display device according to claim 13, wherein each of the first light-emitting element, the second light-emitting element and the third light-emitting element comprises the same light-emitting layer.