Active-matrix device, electro-optical display device, and electronic apparatus

• US 7,952,041 B2
• Filed: 10/13/2008
• Issued: 05/31/2011
• Est. Priority Date: 11/09/2007
• Status: Active Grant

• Current Assignee: 138 East LCD Advancements Limited (Vector Capital Corporation)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Namose, Isamu
• Primary Examiner(s): Friedhofer; Michael A
• Application Number:
  US12/250,023
• Publication Number:
  US 20090120772A1
• Time in Patent Office: 960 Days
• Field of Search: 315/169.3, 315/169.1, 315/169.2, 359/230, 359/237, 359/290, 359/291, 200/181, 335/78
• US Class Current: 200/181
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/1365 in which the switching element is a two-electrode device G02F1/136277 takes precedence

Abstract

An active-matrix device includes a substrate; a plurality of pixel electrodes provided on a first surface of the substrate; a plurality of switching elements provided to correspond to each of the pixel electrodes, each of the switching elements including a fixed electrode connected to the each pixel electrode, a movable electrode displaceably provided to contact with and separate from the fixed electrode, a driving electrode provided to oppose the movable electrode via an electrostatic gap, and an adhesion-preventing mechanism that prevents adhesion between the movable electrode and the driving electrode; a first wiring connected to the movable electrode; and a second wiring connected to the driving electrode, in which a voltage is applied between the movable electrode and the driving electrode to generate an electrostatic attraction between the movable electrode and the driving electrode so as to displace the movable electrode such that the movable electrode contacts with the fixed electrode to electrically connect the first wiring to the pixel electrode.

Claims

1. An active-matrix device, comprising:

a substrate;

a plurality of pixel electrodes provided above a first surface of the substrate;

a plurality of switching elements provided to correspond to each of the pixel electrodes, each of the switching elements including;

a fixed electrode connected to each pixel electrode;

a movable electrode displaceably provided to contact with and separate from the fixed electrode;

a driving electrode provided to oppose the movable electrode via an electrostatic gap; and

an adhesion-preventing mechanism that prevents adhesion between the movable electrode and the driving electrode;

a first wiring connected to the movable electrode; and

a second wiring connected to the driving electrode,

wherein a voltage is applied between the movable electrode and the driving electrode to generate an electrostatic attraction between the movable electrode and the driving electrode so as to displace the movable electrode such that the movable electrode contacts with the fixed electrode to electrically connect the first wiring to the pixel electrode; and

wherein the pixel electrodes are located in positions different from and above those of the switching elements in a thickness direction of the substrate, each pixel electrode is arranged so as to overlap the switching element that corresponds to the pixel electrode when two-dimensionally viewed, and each pixel electrode includes a plurality of apertures.

2. The active matrix device according to claim 1, wherein the adhesion-preventing mechanism is provided on at least one of opposing surfaces of the movable electrode and the driving electrode and includes a release portion having releasability from the movable electrode and/or the driving electrode.

3. The active matrix device according to claim 2, wherein the release portion is formed by a thin film made of a material having the releasability from the movable electrode and/or the driving electrode.

4. The active matrix device according to claim 3, wherein the thin film is an insulating film.

5. The active matrix device according to claim 2, wherein the release portion is formed by a minute concave and convex portion formed on the at least one of the opposing surfaces of the movable electrode and the driving electrode.

6. The active matrix device according to claim 1, wherein the each switching element has a storage space that stores the movable electrode, the driving electrode, and the fixed electrode, and the adhesion-preventing mechanism includes an insulating liquid filled in the storage space and having releasability from the movable electrode and/or the driving electrode.

7. The active matrix device according to claim 1, wherein the fixed electrode, the movable electrode, and the driving electrode are arranged such that the movable electrode contacts with the fixed electrode while remaining separated from the driving electrode, so as to constitute the adhesion-preventing mechanism.

8. The active matrix device according to claim 7, wherein the movable electrode is cantilever-supported to displace a free end side of the movable electrode;

the fixed electrode is located so as to oppose an end region on the free end side of the movable electrode; and

the driving electrode is located relative to the fixed electrode so as to oppose a region on a fixed end side of the movable electrode.

9. The active matrix device according to claim 7, wherein the movable electrode is cantilever-supported to displace a free end side of the movable electrode;

the driving electrode is located so as to oppose an end region on the free end side of the movable electrode; and

the fixed electrode is located relative to the driving electrode so as to oppose a region on a fixed end side of the movable electrode.

10. The active matrix device according to claim 7, wherein on at least one of opposing surfaces of the movable electrode and the fixed electrode, there is formed a protrusion that inhibits the movable electrode from contacting with the driving electrode.

11. The active matrix device according to claim 1, wherein the adhesion-preventing mechanism is provided on at least one of opposing surfaces of the movable electrode and the fixed electrode and includes a release portion having releasability from the movable electrode and/or the fixed electrode.

12. The active matrix device according to claim 1, wherein the first wiring includes a plurality of first wirings provided mutually in parallel along the substrate;

the second wiring includes a plurality of second wirings intersecting with the first wirings and provided mutually in parallel along the substrate; and

the each switching element is provided near an intersection between each of the first wirings and each of the second wirings.

13. An electro-optical display device including the active-matrix device according to claim 1.

14. An electronic apparatus including the electro-optical display device according to claim 13.