Display device and method for driving the same

• US 9,024,927 B2
• Filed: 05/30/2012
• Issued: 05/05/2015
• Est. Priority Date: 06/15/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun
• Primary Examiner(s): Sasinowski, Andrew
• Application Number:
  US13/483,076
• Publication Number:
  US 20120320011A1
• Time in Patent Office: 1,070 Days
• Field of Search: 345/55, 345/102, 345/690, 345/698, 348/51
• US Class Current: 345/205
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: H04N 13/31 using parallax barriers
• CPC Class Codes: H04N 13/359 Switching between monoscopic and stereoscopic modes
• CPC Class Codes: H04N 13/361 Reproducing mixed stereoscopic images; Reproducing mixed monoscopic and stereoscopic images, e.g. a stereoscopic image overlay window on a monoscopic image background
• CPC Class Codes: H04N 13/366 using viewer tracking
• CPC Class Codes: H04N 13/376 for tracking left-right translational head movements, i.e. lateral movements

Abstract

To suppress the increase in power consumption and suppress the decrease in display quality of a display device capable of displaying 3D images, whether each of optical shutters arranged in a matrix is brought into a light-transmitting state or a light-blocking state is selected in accordance with a voltage between a pair of electrodes (a first electrode and a second electrode) of the optical shutter. By control of the voltage between the pair of electrodes, a parallax barrier can be selectively formed in an intended region. Thus, a parallax barrier can be formed only in a region where 3D images are to be displayed.

Claims

1. A display device comprising:

a plurality of switches;

a driver circuit;

a display portion comprising a plurality of pixels arranged in a matrix; and

a shutter portion over a display surface of the display portion, the shutter portion comprising first to fourth stripe shaped electrodes, and a liquid crystal layer,

wherein each of the first and second stripe shaped electrodes intersects with the third and fourth stripe shaped electrodes,

wherein each of first to fourth optical shutters comprises a first electrode, a second electrode, and the liquid crystal layer interposed between the first electrode and the second electrode,

wherein the first electrode of the first and second optical shutters is a part of the first stripe shaped electrode,

wherein the first electrode of the third and fourth optical shutters is a part of the second stripe shaped electrode,

wherein the second electrode of the first and third optical shutters is a part of the third stripe shaped electrode,

wherein the second electrode of the second and fourth optical shutters is a part of the fourth stripe shaped electrode,

wherein one of the plurality of switches is provided between the driver circuit and the first electrode of one of the first to fourth optical shutters, and

wherein each of the first to fourth optical shutters is configured to be brought into a light-blocking state when a first light block signal is input to the first electrode or a second light block signal is input to the second electrode.

2. The display device according to claim 1,

wherein a width of the first electrode and a width of the second electrode are smaller than a width of one of the plurality of pixels.

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

a first substrate where the first electrode is provided; and

a second substrate where the second electrode is provided,

wherein the liquid crystal layer is placed between the first substrate and the second substrate.

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

wherein the first electrode and the second electrode are provided over the substrate.

5. The display device according to claim 1,

wherein the driver circuit is included in the shutter portion.

6. The display device according to claim 1,

wherein each of the plurality of switches is a transistor whose channel is formed in an oxide semiconductor layer.

7. A display device comprising:

a plurality of switches;

a driver circuit;

a display portion comprising a plurality of pixels arranged in a matrix; and

a shutter portion over a display surface of the display portion, the shutter portion comprising first to fourth stripe shaped electrodes, and a liquid crystal layer,

wherein each of the first and second stripe shaped electrodes intersects with the third and fourth stripe shaped electrodes,

wherein each of first to fourth optical shutters comprises a first electrode, a second electrode, and the liquid crystal layer interposed between the first electrode and the second electrode,

wherein the first electrode of the first and second optical shutters is a part of the first stripe shaped electrode,

wherein the first electrode of the third and fourth optical shutters is a part of the second stripe shaped electrode,

wherein the second electrode of the first and third optical shutters is a part of the third stripe shaped electrode,

wherein the second electrode of the second and fourth optical shutters is a part of the fourth stripe shaped electrode,

wherein one of the plurality of switches is provided between the driver circuit and the first electrode of one of the first to fourth optical shutters, and

wherein each of the first to fourth optical shutters is configured to be brought into a light-blocking state when a first light block signal is input to the first electrode and a second light block signal is input to the second electrode.

8. The display device according to claim 7,

wherein a width of the first electrode and a width of the second electrode are smaller than a width of one of the plurality of pixels.

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

a first substrate where the first electrode is provided; and

a second substrate where the second electrode is provided,

wherein the liquid crystal layer is placed between the first substrate and the second substrate.

10. The display device according to claim 7, further comprising a substrate,

wherein the first electrode and the second electrode are provided over the substrate.

11. The display device according to claim 7,

wherein the driver circuit is included in the shutter portion.

12. The display device according to claim 7,

wherein each of the plurality of switches is a transistor whose channel is formed in an oxide semiconductor layer.

13. A driving method of a display device comprising a display portion comprising a plurality of pixels arranged in a matrix, a shutter portion provided over a display surface of the display portion and comprising first to fourth stripe shaped electrodes and a liquid crystal layer, a driver circuit, and a plurality of switches,

wherein each of the first and second stripe shaped electrodes intersects with the third and fourth stripe shaped electrodes,

wherein each of first to fourth optical shutters comprises a first electrode, a second electrode, and the liquid crystal layer interposed between the first electrode and the second electrode,

wherein the first electrode of the first and second optical shutters is a part of the first stripe shaped electrode,

wherein the first electrode of the third and fourth optical shutters is a part of the second stripe shaped electrode,

wherein the second electrode of the first and third optical shutters is a part of the third stripe shaped electrode,

wherein the second electrode of the second and fourth optical shutters is a part of the fourth stripe shaped electrode, and

wherein one of the plurality of switches is provided between the driver circuit and the first electrode of one of the first to fourth optical shutters or between the driver circuit and the second electrode of one of the plurality of first to fourth optical shutters, the driving method comprising the steps of:

turning on the plurality of switches;

inputting a first light block signal to the first electrode and a second light block signal to the second electrode so that the first to fourth optical shutters into which the first light block signal and the second light block signal are input are brought into a light-blocking state, whereby forming a parallax barrier in the shutter portion; and

turning off the plurality of switches,

wherein the parallax barrier remains for a while after the step of turning off the plurality of switches.

14. The driving method according to claim 13, wherein the parallax barrier is formed in part of the shutter portion.

15. The driving method according to claim 13, wherein each of the plurality of switches is a transistor whose channel is formed in an oxide semiconductor layer.

16. The driving method according to claim 13, wherein the driver circuit is provided outside the shutter portion.

17. The driving method according to claim 13,

wherein the display device further comprises a substrate, and

wherein the first electrode and the second electrode are provided over the substrate.