LIQUID CRYSTAL DEVICE, ELECTRONIC APPARATUS, AND METHOD OF MANUFACTURING LIQUID CRYSTAL DEVICE

• US 20100079694A1
• Filed: 08/12/2009
• Published: 04/01/2010
• Est. Priority Date: 09/30/2008
• Status: Active Grant

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Epson Imaging Devices Corporation (Seiko Group)
• Inventors: YOSHIDA, Koji, TAKIZAWA, Keiji, HIGA, Masakatsu, TANAKA, Shinichiro, YOSHIDA, Shuhei, NISHIMURA, Joji
• Granted Patent: US 8,310,609 B2
• Time in Patent Office: Days
• US Class Current: 349/40
• CPC Class Codes: G02F 1/133334 Electromagnetic shields
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

Provided is a lateral electric field mode liquid crystal device including: a first substrate; a second substrate; a liquid crystal layer and pixel electrodes and common electrodes. A lateral electric field mode liquid crystal device drives the liquid crystal layer by an electric field generated between the pixel electrodes and the common electrodes, a light shielding layer is formed on a surface of the second substrate disposed close to the liquid crystal layer. A coloring layer is also formed so as to overlap with the pixel electrodes. An overcoat layer protects the coloring layer, and an alignment film is formed. An electrostatic shielding layer is formed of a transparent conductive material on a surface of the overcoat layer.

Claims

1. A lateral electric field mode liquid crystal device comprising:

a first substrate;

a second substrate;

a liquid crystal layer sandwiched between the first substrate and the second substrate; and

pixel electrodes and common electrodes which are formed on a surface of the first substrate disposed close to the liquid crystal layer, the lateral electric field mode liquid crystal device driving the liquid crystal layer by an electric field generated between the pixel electrodes and the common electrodes,

wherein on a surface of the second substrate disposed close to the liquid crystal layer, a light shielding layer which is formed in areas including an area disposed between the pixel electrodes in a plan view and is capable of absorbing at least visible light, a coloring layer which is formed so as to overlap with the pixel electrodes in a plan view and is capable of transmitting light in a particular wavelength range, an overcoat layer for protecting the coloring layer, and an alignment film are formed in this order, and

wherein an electrostatic shielding layer formed of a transparent conductive material is formed on a surface of the overcoat layer disposed close to the second substrate and a surface of the light shielding layer disposed close to the liquid crystal layer.

2. The liquid crystal device according to claim 1, wherein the coloring layer is formed on a surface of the electrostatic shielding layer disposed close to the liquid crystal layer.

3. The liquid crystal device according to claim 1, wherein the coloring layer is formed on a surface of the electrostatic shielding layer disposed close to the second substrate.

4. The liquid crystal device according to claim 2, wherein the electrostatic shielding layer is not formed in at least a portion of an outer edge portion of the second substrate.

5. The liquid crystal device according to claim 4, wherein steps are formed at a boundary portion of the light shielding layer and the coloring layer, and an uneven surface resembling the steps is formed on a top surface of the electrostatic shielding layer.

6. The liquid crystal device according to claim 1,

wherein a driving circuit and drawing lines electrically connected to the driving circuit are formed on the surface of the first substrate disposed close to the liquid crystal layer,

wherein the drawing lines and the electrostatic shielding layer are electrically connected at positions where they overlap with each other in a plan view via a conductive member sandwiched between the first substrate and the second substrate, and

wherein the potential of the electrostatic shielding layer is controlled to be at predetermined potential by the driving circuit.

7. The liquid crystal device according to claim 6, wherein the potential of the electrostatic shielding layer is controlled to be at the same potential as the common electrodes.

8. The liquid crystal device according to claim 6,

wherein the first substrate has an insulating film which covers the drawing lines,

wherein contact holes are formed in the insulating film so as to expose portions of the drawing lines to a bottom portion thereof,

wherein a conductive film is formed in an inner portion of each of the contact holes so as to cover the drawing lines exposed to the bottom portion, and

wherein the electrostatic shielding layer is electrically connected to the drawing lines via the conductive member and the conductive film.

9. The liquid crystal device according to claim 8, wherein the conductive film is formed of conductive metal oxides.

10. The liquid crystal device according to claim 1,

wherein the pixel electrodes and the common electrodes are laminated on the surface of the first substrate disposed close to the liquid crystal layer via the insulating film, and

wherein the common electrodes are disposed closer to the liquid crystal layer than the pixel electrodes.

11. The liquid crystal device according to claim 1,

wherein a sealing member for sealing liquid crystal molecules is provided around the liquid crystal layer,

wherein a display area defined by the plurality of pixel electrodes is formed at an inner side of the area surrounded by the sealing member, and a non-display area is formed between the display area and the sealing member at the inner side of the area surrounded by the sealing member,

wherein electrostatic protection members capable of discharging static electricity entering into the display area are arranged on the non-display area of the first substrate, and

wherein the electrostatic shielding layer is disposed so as to overlap with the electrostatic protection members in a plan view.

12. An electronic apparatus comprising the liquid crystal device according to claim 1.

13. A method of manufacturing a lateral electric field mode liquid crystal device comprising:

a first substrate and a second substrate which are disposed to face each other;

a liquid crystal layer which is sandwiched between the first substrate and the second substrate;

pixel electrodes and common electrodes which are formed on a surface of the first substrate disposed close to the liquid crystal layer;

a light shielding layer which is formed on a surface of the second substrate, in a plan view, disposed close to the liquid crystal layer in areas including an area disposed between the pixel electrodes and is capable of absorbing at least visible light; and

an electrostatic shielding layer which is formed on a surface of the light shielding layer disposed close to the liquid crystal layer and is formed of a transparent conductive material, the lateral electric field mode liquid crystal device driving the liquid crystal layer by an electric field generated between the pixel electrodes and the common electrodes, the method comprising the steps of;

forming a light shielding material layer on one surface of the second substrate;

patterning the light shielding material layer to form openings and alignment marks which correspond to areas including the pixel electrodes in a plan view;

disposing a film forming mask so as to face the one surface to positioning the second substrate and the film forming mask using the alignment marks; and

forming a transparent conductive material layer on the one surface via the film forming mask to form the electrostatic shielding layer.