DISPLAY DEVICE AND ELECTRONIC APPARATUS INCLUDING DISPLAY DEVICE

• US 20080278667A1
• Filed: 05/08/2008
• Published: 11/13/2008
• Est. Priority Date: 05/08/2007
• Status: Active Grant

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Epson Imaging Devices Corporation (Seiko Group)
• Inventors: KOBASHI, Yutaka
• Granted Patent: US 8,674,971 B2
• Time in Patent Office: Days
• US Class Current: 349/116
• CPC Class Codes: G02F 1/13318 Circuits comprising a photodetector
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A display device includes an active matrix circuit for display, a plurality of bus lines which are connected to the active matrix circuit and which are used to transmit driving signals, driving circuits which supply the driving signals to the plurality of bus lines, the plurality of bus lines and the driving circuits being arranged on a substrate, and optical sensors arranged on the substrate. The optical sensors are arranged in a plurality of sub regions separated using the plurality of bus lines. The plurality of sub regions are arranged between the active matrix circuit and each of the driving circuits.

Claims

1. A display device comprising:

an active matrix circuit for display;

a plurality of bus lines which are connected to the active matrix circuit and which are used to transmit driving signals;

driving circuits which supply the driving signals to the plurality of bus lines, the plurality of bus lines and the driving circuits being arranged on a substrate; and

optical sensors arranged on the substrate,

wherein the optical sensors are arranged in a plurality of sub regions separated using the plurality of bus lines, and

the plurality of sub regions are arranged between the active matrix circuit and each of the driving circuits.

2. The display device according to claim 1, further comprising:

a plurality of pixel electrodes connected to the active matrix circuit;

a common electrode driven so that a potential of the common electrode is switched between a first potential and a second potential which is lower than the first potential;

liquid crystal elements alignment states of which are changed in accordance with an electric field applied between the plurality of pixel electrodes and the common electrode;

sensor lines connected to the optical sensors; and

a detection circuit which is connected to the sensor lines and which detects potentials or currents of the sensor lines,

wherein the detection circuit detects the potentials or the currents of the sensor lines when a first period of time which is one of a period of time in which the potential of the common electrode corresponds to the first potential and a period of time in which the potential of the common electrode corresponds to the second potential is entered.

3. The display device according to claim 2,

wherein the detection circuit repeatedly performs a resetting operation of resetting the potentials of the sensor lines to initial states, and

the resetting operation is performed in a second period of time which is the other of the period of time in which the potential of the common electrode corresponds to the first potential and the period of time in which the potential of the common electrode corresponds to the second potential is entered.

4. The display device according to claim 2,

wherein the potentials of the sensor lines are changed when the potential of the common electrode is changed.

5. The display device according to claim 3,

wherein the sensor lines are short-circuited to the common electrode.

6. The display device according to claim 3,

wherein the sensor lines are connected to power supply lines which receive potentials supplied from an external device in the second period of time, and are brought to floating states in the first period of time.

7. The display device according to claim 1, further comprising:

first electrodes arranged in regions overlapped with the optical sensors in a plan view; and

second electrodes arranged in regions in which the first electrodes are overlapped with the bus lines.

8. The display device according to claim 7,

wherein the second electrodes are connected to the common electrode.

9. The display device according to claim 8,

wherein the first electrodes function as a plurality of light-shielding electrodes for shielding backlight, and

the bus lines and the second electrodes are arranged in gaps interposed among the plurality of light-shielding electrodes.

10. The display device according to claim 1,

wherein the plurality of sub regions are arranged along four sides of the active matrix circuit.

11. The display device according to claim 2, further comprising:

a plurality of detection circuits; and

a majority determination circuit connected to the plurality of detection circuits,

wherein the majority determination circuit changes an output signal when at least two of a plurality of results of detections output from the plurality of determination circuits are changed.

12. The display device according to claim 11,

wherein the plurality of detection circuits include a first and a second detection circuits, and

among the plurality of sub regions, sub regions connected to the first detection circuit and sub regions connected to the second detection circuit are arranged on different sides of the active matrix circuit.

13. The display device according to claim 1,

wherein the optical sensors are PIN junction diodes or PN junction diodes formed of polysilicon thin films, and the driving circuits include polysilicon thin film transistors.

14. An electronic apparatus including the display device according to claim 1.