DISPLAY DEVICE AND ELECTRONIC DEVICE

• US 20110057918A1
• Filed: 08/31/2010
• Published: 03/10/2011
• Est. Priority Date: 09/04/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Tsubuku, Masashi, Sasaki, Toshinari, Kimura, Hajime, Akimoto, Kengo
• Granted Patent: US 9,257,082 B2
• Time in Patent Office: Days
• US Class Current: 345/211
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 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 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/78693 the semiconducting oxide being amorphous

Abstract

A display device including a pixel having a memory. The pixel includes at least a display element, a capacitor, an inverter, and a switch. The switch is controlled with a signal held in the capacitor and a signal output from the inverter so that voltage is supplied to the display element. The inverter and the switch can be constituted by transistors with the same polarity. A semiconductor layer included in the pixel may be formed using a light-transmitting material. Moreover, a gate electrode, a drain electrode, and a capacitor electrode may be formed using a light-transmitting conductive layer. The pixel is formed using a light-transmitting material in such a manner, whereby the display device can be a transmissive display device while including a pixel having a memory.

Claims

1. A display device comprising:

a display element comprising a pixel electrode;

a first circuit configured to control input of an image signal;

a second circuit configured to hold the image signal; and

a third circuit configured to control polarity of a voltage supplied to the pixel electrode,

wherein the first circuit, the second circuit, and the third circuit are formed using a light-transmitting material, and

wherein the pixel electrode is provided above the first circuit, the second circuit, and the third circuit.

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

a fourth circuit,

wherein the first circuit, the second circuit, the third circuit and the display element are positioned in a pixel portion,

wherein the fourth circuit is configured to control the pixel portion, and

wherein the fourth circuit is formed using a material different from the light-transmitting material.

3. An electronic device comprising the display device according to claim 1, and an operation switch.

4. A display device comprising:

a first circuit comprising;

a first switch;

a second circuit comprising;

a first capacitor;

a second capacitor; and

an inverter comprising an input terminal electrically connected to the first capacitor and an output terminal electrically connected to the second capacitor;

a third circuit comprising;

a second switch comprising a control terminal electrically connected to the first capacitor; and

a third switch comprising a control terminal electrically connected to the second capacitor; and

a display element comprising a pixel electrode electrically connected to the second switch and the third switch,

wherein an image signal is input to the first capacitor and the second capacitor through the first switch.

5. The display device according to claim 4, further comprising:

a first wiring electrically connected to the first capacitor through the first switch;

a second wiring; and

a third wiring electrically connected to the second wiring through the second switch and the third switch.

6. The display device according to claim 4, further comprising:

a first wiring electrically connected to the first capacitor through the first switch;

a second wiring; and

a third wiring electrically connected to the second wiring through the second switch and the third switch,

wherein the image signal is input to the first wiring.

7. The display device according to claim 4,

wherein the pixel electrode, the first switch, the second switch, the third switch, the first capacitor, the second capacitor, and the inverter comprise a light-transmitting layer, and

wherein the pixel electrode is provided above the first switch, the second switch, the third switch, the first capacitor, the second capacitor, and the inverter.

8. The display device according claim 4, further comprising:

a fourth circuit electrically connected to the first circuit,

wherein the pixel electrode, the first switch, the second switch, the third switch, the first capacitor, the second capacitor, and the inverter comprise a light-transmitting layer, and

wherein the fourth circuit comprise a layer different from the light-transmitting layer.

9. An electronic device comprising the display device according to claim 4, and an operation switch.