In plane switching liquid crystal displaying apparatus for improved luminance

• US 6,864,939 B2
• Filed: 12/12/2003
• Issued: 03/08/2005
• Est. Priority Date: 10/16/1997
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Masutani, Yuichi, Kobayashi, Kazuhiro, Nakashima, Ken, Niwano, Yasunori, Oodoi, Yuuzou
• Primary Examiner(s): NGO, HUYEN LE
• Application Number:
  US10/733,364
• Publication Number:
  US 20040119928A1
• Time in Patent Office: 452 Days
• Field of Search: 349/141, 349/38, 349/43
• US Class Current: 349/141
• 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 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer

Abstract

An IPS liquid crystal displaying apparatus includes: a TFT array substrate, an opposite substrate opposed to the TFT array substrate and liquid crystal interposed between the TFT array substrate and the opposite substrate, wherein the TFT array substrate is composed of a glass substrate, a gate insulating film formed on the glass substrate, a possivation film formed on the gate insulating film, a plurality of scanning lines for transmitting a scanning signal, a plurality of signal lines for transmitting an image signal, a plurality of pixels arranged in grid like pattern by crossing the plurality of scanning lines with the plurality of signal lines, a plurality of TFTs implementing switching operation of the image signal on the basis of the scanning signals, a plurality of driving electrodes connected with the TFT, a plurality of opposite electrodes arranged in such a manner that each of the plurality of opposite electrodes is opposed to each of the driving electrodes, and a plurality of common lines for mutually connecting each of the opposite electrode of one of the plurality of pixels with the other one of the plurality of pixels, wherein the TFT array substrate is formed on the passivation film, the passivation film being different from a layer provided with the driving electrode and the opposite electrode.

Claims

1. An In Plane Switching (IPS) liquid crystal displaying apparatus, comprising:

a Thin Film Transistor (TFT) array substrate;

an opposite substrate opposed to said TFT array substrate; and

liquid crystal interposed between said TFT array substrate and said opposite substrate,

wherein said TFT array substrate comprises,

a glass substrate,

a gate insulating film formed on said glass substrate,

a passivation film formed on said gate insulating film,

a plurality of scanning lines configured to transmit a plurality of scanning signals and formed on said glass substrate,

a plurality of signal lines configured to transmit a plurality of image signals and formed on said gate insulating film,

a plurality of pixels arranged in a grid like pattern by crossing said plurality of scanning lines with said plurality of signal lines,

a plurality of TFTs implementing a switching operation of said plurality of image signals based on said plurality of scanning signals,

a plurality of driving electrodes formed on said passivation film and connected with said plurality of TFTs,

a plurality of opposite electrodes formed on said passivation film, each of said plurality of opposite electrodes opposing each of said plurality of driving electrodes, and

a plurality of common lines configured to connect each of said plurality of opposite electrodes with each of said plurality of pixels,

wherein said TFT array substrate includes at least one common line of said plurality of common lines and at least one scanning line of said plurality of scanning lines on a same layer, and at least one signal line of said plurality of signal lines provided on said gate insulating film.

2. The IPS liquid crystal displaying apparatus of claim 1, wherein said TFT array substrate is provided with said passivation film, a surface of which is approximately flat in shape.