Electrowetting device

1. An electrowetting device comprising:

an electrode substrate including a first substrate, a plurality of first drive electrodes formed on the first substrate, and a water-repellent insulating layer formed on the plurality of first drive electrodes;

a counter substrate including a second substrate, and disposed so as to face the electrode substrate with a predetermined gap therebetween;

a sealing portion provided in a sealing region at the electrode substrate, and bonding the electrode substrate and the counter substrate; and

at least one injection valve for injecting a droplet into the gap, the injection valve being located in the sealing region and including a first valve body formed of an electric field responsive gel.

2. The electrowetting device according to claim 1 , wherein

the injection valve includes the first valve body and an injection valve electrode pair for sandwiching at least a part of the first valve body and applying a voltage to the first valve body, and

the injection valve electrode pair includes a first injection valve electrode wholly or partially located in an inner region inside the sealing region at the electrode substrate.

3. The electrowetting device according to claim 1 , further comprising

an exhaust valve for taking out air in the gap, the exhaust valve being located in the sealing region, and including a second valve body formed of an electric field responsive gel.

4. The electrowetting device according to claim 3 , wherein

the exhaust valve includes the second valve body and an exhaust valve electrode pair for sandwiching at least a part of the second valve body and applying a voltage to the second valve body,

the exhaust valve electrode pair includes a first exhaust valve electrode wholly or partially located in an inner region inside the sealing region, and

a first injection valve electrode and the first exhaust valve electrode are electrically connected to a first terminal electrode via a first wiring line.

5. The electrowetting device according to claim 4 , wherein

the electrode substrate further includes the first terminal electrode for externally supplying a desired control signal for controlling opening/closing of the injection valve and the exhaust valve, and

the first injection valve electrode and the first exhaust valve electrode are electrically connected to the first terminal electrode via the first wiring line.

6. The electrowetting device according to claim 4 , wherein

the electrode substrate further includes a second terminal electrode different from the first terminal electrode, for externally supplying a desired control signal for controlling opening/closing of the injection valve and the exhaust valve,

an injection valve electrode pair includes the first injection valve electrode and a second injection valve electrode located in an outer region outside the sealing region at the electrode substrate, and the first injection valve electrode and the second injection valve electrode sandwich a part of the first valve body,

the exhaust valve electrode pair includes the first exhaust valve electrode and a second exhaust valve electrode located in the outer region, and the first exhaust valve electrode and the second exhaust valve electrode sandwich a part of the second valve body, and

the second injection valve electrode and the second exhaust valve electrode are electrically connected to the second terminal electrode via a second wiring line.

7. The electrowetting device according to claim 4 , wherein

the counter substrate further includes a second terminal electrode different from the first terminal electrode, for externally supplying a desired control signal for controlling opening/closing of the injection valve and the exhaust valve,

an injection valve electrode pair includes the first injection valve electrode and a second injection valve electrode located in a sealing region at the counter substrate, and in a direction normal to the electrode substrate, the first injection valve electrode and the second injection valve electrode sandwich a part of the first valve body,

the exhaust valve electrode pair includes the first exhaust valve electrode and a second exhaust valve electrode located in the sealing region at the counter substrate, and in the direction normal to the electrode substrate, the first exhaust valve electrode and the second exhaust valve electrode sandwich a part of the second valve body, and

the second injection valve electrode and the second exhaust valve electrode are electrically connected to the second terminal electrode via a second wiring line.

8. The electrowetting device according to claim 6 , wherein

the at least one injection valve includes a plurality of injection valves, and

the plurality of injection valves are disposed along a column direction, and a part of the sealing portion is present between the first valve bodies of two of the plurality of injection valves adjacent to each other.

9. The electrowetting device according to claim 7 , wherein

the at least one injection valve includes a plurality of injection valves, and

the plurality of injection valves are disposed along a column direction, and the first valve bodies of two of the plurality of injection valves adjacent to each other are in contact with each other when the injection valves are closed.

10. The electrowetting device according to claim 4 ,

wherein each of the first valve body and the second valve body is formed of a polyvinyl chloride gel.

11. The electrowetting device according to claim 4 ,

wherein an area of a second injection valve electrode is smaller than an area of the first injection valve electrode, and an area of a second exhaust valve electrode is smaller than an area of the first exhaust valve electrode.

12. The electrowetting device according to claim 4 , wherein

the injection valve is opened by applying a positive voltage to the first injection valve electrode of an injection valve electrode pair and applying a negative or zero voltage to a second injection valve electrode of the injection valve electrode pair, and the injection valve is closed by applying a negative or zero voltage to the first injection valve electrode and applying a positive voltage to the second injection valve electrode, and

the exhaust valve is opened by applying a positive voltage to the first exhaust valve electrode of the exhaust valve electrode pair and applying a negative or zero voltage to a second exhaust valve electrode, and the exhaust valve is closed by applying a negative or zero voltage to the first exhaust valve electrode and applying a positive voltage to the second injection valve electrode.

13. The electrowetting device according to claim 1 ,

wherein the injection valve includes an injection valve electrode for applying a voltage to the first valve body, the injection valve electrode being wholly or partially located in an inner region inside the sealing region at the electrode substrate.

14. The electrowetting device according to claim 13 , further comprising

an exhaust valve for taking out air in the gap, the exhaust valve being located in the sealing region, and including a second valve body formed of an electric field responsive gel,

wherein the exhaust valve includes an exhaust valve electrode for applying a voltage to the second valve body, the exhaust valve electrode being wholly or partially located in the inner region.

15. The electrowetting device according to claim 1 ,

wherein the counter substrate further includes a plurality of second drive electrodes formed on the second substrate and a second water-repellent insulating layer formed on the second drive electrodes.

16. The electrowetting device according to claim 1 ,

wherein the plurality of first drive electrodes are passive matrix electrodes arranged in rows and columns.