DISPLAY DEVICE, DISPLAY MODULE, AND ELECTRONIC DEVICE

• US 20170365224A1
• Filed: 06/13/2017
• Published: 12/21/2017
• Est. Priority Date: 06/16/2016
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: OKAMOTO, Yuki
• Granted Patent: US 10,431,164 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/13 based on liquid crystals, e.g. single liquid crystal display cells
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 2203/30 Gray scale
• CPC Class Codes: G09G 2300/0456 with a reflective area and a transmissive area combined in one pixel, such as in transflectance pixels
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2300/0804 Sub-multiplexed active matrix panel, i.e. wherein one active driving circuit is used at pixel level for multiple image producing elements
• CPC Class Codes: G09G 2310/0286 Details of a shift registers arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0686 with two or more screen areas displaying information with different brightness or colours
• CPC Class Codes: G09G 2330/023 using energy recovery or conservation
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/148 the light being detected by light detection means within each pixel
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/346 : based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G11C 19/28 : using semiconductor elements G11C19/14, G11C19/36 take precedence
• CPC Class Codes: H01L 27/1225 : with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785

Abstract

A display device with low power consumption is provided. A display device having high visibility regardless of the ambient brightness is provided. The display device includes a light-receiving element, a display element, a first transistor, and a second transistor. One of a source and a drain of the first transistor is electrically connected to one electrode of the light-receiving element. The one of the source and the drain of the first transistor is electrically connected to one of a source and a drain of the second transistor. The display device has a function of, by turning on the second transistor, changing the gray level of the display element in accordance with the amount of light detected by the light-receiving element.

Claims

1. A display device comprising:

a light-receiving element;

a display element;

a first transistor; and

a second transistor,

wherein one of a source and a drain of the first transistor is electrically connected to a first electrode of the light-receiving element,

wherein the one of the source and the drain of the first transistor is electrically connected to one of a source and a drain of the second transistor, and

wherein the display device is configured to, by turning on the second transistor, change a gray level of the display element in accordance with the amount of light detected by the light-receiving element.

2. The display device according to claim 1, wherein the gray level of the display element increases with an increase in the amount of light detected by the light-receiving element.

3. A display module comprising:

the display device according to claim 1; and

a circuit board.

4. An electronic device comprising:

the display module according to claim 3; and

at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button.

5. A display device comprising:

a photodetector circuit; and

a pixel circuit,

wherein the photodetector circuit comprises;

a light-receiving element;

a first transistor; and

a second transistor,

wherein the pixel circuit comprises;

a light-emitting element; and

a third transistor,

wherein one of a source and a drain of the first transistor is electrically connected to a first electrode of the light-receiving element,

wherein the one of the source and the drain of the first transistor is electrically connected to one of a source and a drain of the second transistor,

wherein the other of the source and the drain of the second transistor is electrically connected to one of two gates of the third transistor, and

wherein one of a source and a drain of the third transistor is electrically connected to a first electrode of the light-emitting element.

6. The display device according to claim 5,

wherein the pixel circuit further comprises a liquid crystal element that reflects visible light.

7. The display device according to claim 5, further comprising a signal generation circuit,

wherein the pixel circuit comprises a fourth transistor,

wherein one of a source and a drain of the fourth transistor is electrically connected to the other of the two gates of the third transistor,

wherein the photodetector circuit is configured to output a first signal corresponding to the amount of light detected by the light-receiving element, and

wherein the signal generation circuit is configured to generate a second signal corresponding to the first signal and supply the second signal to a gate of the fourth transistor.

8. The display device according to claim 7,

wherein the photodetector circuit comprises a fifth transistor, and

wherein one of a source and a drain of the fifth transistor is electrically connected to the one of the source and the drain of the first transistor and the other of the source and the drain of the fifth transistor is electrically connected to the first electrode of the light-receiving element.

9. The display device according to claim 5, wherein the second transistor comprises an oxide semiconductor in a channel formation region.

10. The display device according to claim 5,

wherein the display device is configured to detect a touch motion,

wherein the pixel circuit is electrically connected to a sensor driver circuit, and

wherein the photodetector circuit is configured to output, to the sensor driver circuit, a signal corresponding to the amount of light detected by the light-receiving element.

11. A display module comprising:

the display device according to claim 5; and

a circuit board.

12. An electronic device comprising:

the display module according to claim 11; and

at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button.

13. A display device comprising:

a photodetector circuit; and

a pixel circuit,

wherein the photodetector circuit comprises;

a light-receiving element;

a first transistor; and

a second transistor,

wherein the pixel circuit comprises;

a liquid crystal element; and

a third transistor,

wherein one of a source and a drain of the first transistor is electrically connected to a first electrode of the light-receiving element,

wherein the one of the source and the drain of the first transistor is electrically connected to one of a source and a drain of the second transistor,

wherein the other of the source and the drain of the second transistor is electrically connected to one of a source and a drain of the third transistor, and

wherein the one of the source and the drain of the third transistor is electrically connected to a first electrode of the liquid crystal element.

14. The display device according to claim 13,

wherein the photodetector circuit comprises a fourth transistor, and

wherein one of a source and a drain of the fourth transistor is electrically connected to the one of the source and the drain of the first transistor and the other of the source and the drain of the fourth transistor is electrically connected to the first electrode of the light-receiving element.

15. The display device according to claim 13, wherein the second transistor comprises an oxide semiconductor in a channel formation region.

16. The display device according to claim 13,

wherein the display device is configured to detect a touch motion,

wherein the pixel circuit is electrically connected to a sensor driver circuit, and

wherein the photodetector circuit is configured to output, to the sensor driver circuit, a signal corresponding to the amount of light detected by the light-receiving element.

17. A display module comprising:

the display device according to claim 13; and

a circuit board.

18. An electronic device comprising:

the display module according to claim 17; and

at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button.