Display device

• US 20050104804A1
• Filed: 01/24/2003
• Published: 05/19/2005
• Est. Priority Date: 02/19/2002
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Liquavista B.V. (Amazon.com, Inc.)
• Inventors: Feenstra, Bokke Johannes, Prins, Menno Willem Jose, Hayes, Robert Andrew
• Granted Patent: US 7,463,398 B2
• Time in Patent Office: Days
• US Class Current: 345/41
• CPC Class Codes: G02B 2207/115 Electrowetting
• CPC Class Codes: G02B 26/005 based on electrowetting
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field

Abstract

Display device based on layer break up or layer displacement having at least two different states, in which one of the fluids (5) e.g oil in a first state adjoins at least a first support plate (3) and in the second state the other fluid (6) at least partly adjoins the first support plate. In one embodiment a picture element corresponds to a substantially closed space and in the first state the other fluid layer substantially completely adjoins both support plates and is divided in two sub-layers. This makes it possible on the one hand to use lower voltages to make displacement occur. On the other hand this opens the opportunity to color displays.

Claims

1. A display device comprising picture elements having a first fluid and at least one second fluid immiscible with each other within a space between a first support plate and a second support plate, the first fluid being electroconductive or polar, the device comprising means for creating at least two different states, in which one of the fluids in a first state adjoins at least the first support plate and in the second state the other fluid at least partly adjoins the first support plate.

2. A display device according to claim 1 in which a picture element corresponds to a defined space and in the second state the other fluid substantially completely adjoins the first support plate.

3. A display device according to claim 1, the device comprising means for creating within a picture element an inhomogeneous electric field at the surface of the part of the first support plate.

4. A display device according to claim 3 in which a dielectric layer between an electrode and a surface layer of the part of the first support plate varies in thickness.

5. A display device according to claim 3 in which a dielectric layer between an electrode and the surface of the part of the first support plate has a varying dielectric constant.

6. A display device according to claim 1, the device within a picture element having a varying wettability at the surface of the part of the first support plate or a varying thickness of the first fluid layer.

7. A display device according to claim 1 in which a picture element corresponds to a defined space and in the first state a first fluid layer substantially completely adjoins both support plates.

8. A display device according to claim 1 in which a picture element corresponds to a defined space having a wall part dividing the space into at least two sub-picture elements, in the first state a further fluid layer adjoining the first support plate at least partly within both sub-picture elements.

9. A display device according to claim 8 in which the first fluid layer and the further fluid layer have different colors.

10. A display device according to claim 2 in which in the second state at least one of the first fluid layer and the further fluid layer adjoins a wall part of the space.

11. A display device according to claim 10 which comprises means to prevent part of the first fluid layer and the further fluid layer to intermix in the second state.

12. A display device according to claim 1 which comprises driving means to obtain intermediate states.

13. A display device according to claim 1 which comprises an absorber or a reflector at the side of the first substrate.

14. A display device according to claim 2 in which the other layer is a scattering or an absorbing layer.

15. A display device according to claim 2 in which the other layer is common to several picture elements.

16. A display device according to claim 1 which comprises a color filter.

17. A diffusing device having a first fluid and at least one second fluid immiscible with each other and confined in a space between a first support plate and a second support plate, the first fluid being electroconductive or polar, the device comprising means for creating at least two different states, in which one of the fluids in a first state adjoins at least the first support plate and in the second state the other fluid at least partly adjoins the first support plate.