Liquid crystal display device comprising a transparent pixel electrode connected with a thin film transistor through a contact hole and a transparent counter electrode having multiple slits

• US 9,261,747 B2
• Filed: 09/30/2014
• Issued: 02/16/2016
• Est. Priority Date: 09/04/2007
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Japan Display Incorporated, Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Sasaki, Tohru, Ochiai, Takahiro
• Primary Examiner(s): Lee, Paul
• Application Number:
  US14/502,108
• Publication Number:
  US 20150055044A1
• Time in Patent Office: 504 Days
• Field of Search: 349/38, 349/42, 349/43, 349/139, 349/141, 349/147
• US Class Current: 1/1
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• 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 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/13629 Multilayer wirings
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors

Abstract

To form a sufficiently large storage capacitor, a liquid crystal display device includes a liquid crystal display panel having a first substrate, a second substrate, and a liquid crystal held between the first substrate and the second substrate, the liquid crystal display panel having multiple pixels arranged in matrix. The first substrate has, in a transmissive display area provided in each of the pixels, a laminated structure containing a first transparent electrode, a first insulating film, a second transparent electrode, a second insulating film, and a third transparent electrode which are laminated in this order. The first transparent electrode and the second transparent electrode are electrically insulated from each other and together form a first storage capacitor through the first insulating film, and the second transparent electrode and the third transparent electrode are electrically insulated from each other and together form a second storage capacitor through the second insulating film.

Claims

1. A liquid crystal display device comprising:

a first substrate;

a second substrate; and

a liquid crystal held between the first substrate and the second substrate, wherein the first substrate has

a transparent pixel electrode formed in each pixel;

a second insulating film covering the transparent pixel electrode;

a common metal wiring line formed on an upper side of the second insulating film; and

a transparent counter electrode opposite to the transparent pixel electrode across the second insulating film, the transparent counter electrode being formed on the second insulating film and the common metal wiring line to electrically connect with the common metal wiring line, wherein

the transparent pixel electrode is connected with a thin film transistor formed in each pixel through a contact hole on a layer lower than the transparent pixel electrode,

the transparent counter electrode has multiple slits formed therein and includes a portion located in the contact hole, and

at least one of the multiple slits is formed in the portion of the transparent counter electrode.

2. A liquid crystal display device according to claim 1, wherein

a first insulating film, the transparent pixel electrode, the second insulating film, the common metal wiring line, and the transparent counter electrode are laminated in this order from the first substrate,

the first insulating film has a contact hole formed thereon

a transparent electrode pattern is formed in a same layer as the transparent pixel electrode,

the transparent electrode pattern, the second insulating film, the common metal wiring line, and the transparent counter electrode are laminated around the contact hole.

3. A liquid crystal display device according to claim 1, wherein

the transparent counter electrode extends to cover the common metal wiring line and directly contact with the common metal wiring line.

4. A liquid crystal display device according to claim 2, wherein

the transparent counter electrode extends to cover the common metal wiring line and directly contact with the common metal wiring line.

5. A liquid crystal display device according to claim 3, wherein

the transparent counter electrode has a larger width in a direction along a scanning line than that of the transparent pixel electrode, and

the transparent counter electrode has a larger width in a direction along a signal line than that of the transparent pixel electrode.

6. A liquid crystal display device according to claim 4, wherein

the transparent counter electrode has a larger width in a direction along a scanning line than that of the transparent pixel electrode, and

the transparent counter electrode has a larger width in a direction along a signal line than that of the transparent pixel electrode.