JP2003222837A - Thin film transistor type liquid crystal display panel - Google Patents
Thin film transistor type liquid crystal display panelInfo
- Publication number
- JP2003222837A JP2003222837A JP2002022213A JP2002022213A JP2003222837A JP 2003222837 A JP2003222837 A JP 2003222837A JP 2002022213 A JP2002022213 A JP 2002022213A JP 2002022213 A JP2002022213 A JP 2002022213A JP 2003222837 A JP2003222837 A JP 2003222837A
- Authority
- JP
- Japan
- Prior art keywords
- liquid crystal
- thin film
- film transistor
- crystal display
- display panel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、薄膜トランジスタ
（以下、薄膜トランジスタをＴＦＴと称す）を用いたＴ
ＦＴ型液晶表示パネルに関するものである。TECHNICAL FIELD The present invention relates to a T using a thin film transistor (hereinafter, the thin film transistor is referred to as a TFT).
The present invention relates to an FT type liquid crystal display panel.
【０００２】[0002]
【従来の技術】図３は従来のパネル構成において、対向
電極基板２上から見た模式斜視図である。３ａ、３ｂは
それぞれＴＦＴ基板１及び対向電極基板２のラビング軸
方位を表し、その軸交角は９０゜である。また、１４は
位相差フィルムを、４ａ、４ｂはそれぞれＴＦＴ基板側
及び対向電極基板側の位相差フィルムの光軸方位を示
す。また、１５は偏光板を、５ａ、５ｂはそれぞれＴＦ
Ｔ基板側及び対向電極基板側の偏光版の吸収軸方位を示
す。ここで、３ａ、４ａ、５ａ及び３ｂ、４ｂ、５ｂは
それぞれ同一方位に配置される。１６は液晶である。2. Description of the Related Art FIG. 3 is a schematic perspective view of a conventional panel structure as viewed from above a counter electrode substrate 2. 3a and 3b represent the rubbing axis directions of the TFT substrate 1 and the counter electrode substrate 2, respectively, and the axis intersecting angle is 90 °. Further, 14 is a retardation film, and 4a and 4b are optical axis directions of the retardation film on the TFT substrate side and the counter electrode substrate side, respectively. Further, 15 is a polarizing plate, 5a and 5b are TF, respectively.
The absorption axis directions of the polarizing plates on the T substrate side and the counter electrode substrate side are shown. Here, 3a, 4a, 5a and 3b, 4b, 5b are arranged in the same direction. Reference numeral 16 is a liquid crystal.
【０００３】図４は、従来のＴＦＴ型液晶表示パネルの
駆動電圧波形を示す。６ａ、１１ｂはそれぞれゲート電
極のＯＮ電圧（ＶｇＨ）及びＯＦＦ電圧（ＶｇＬ）を示
し、７はソース電圧（Ｖｓｉｇ）、８は対向電圧（Ｖｃ
ｏｍ）、９はドレイン電圧（Ｖｐ）及び１０は液晶印加
電圧（Ｖｌｃ）を示す。ここで、９ａは欠陥画素におけ
るドレイン電圧（Ｖｐ-ｄ）を、９ｂは正常画素におけ
るドレイン電圧（Ｖｐ-ｎ）を示す。また、１０ａは欠
陥画素における液晶印可電圧（Ｖｌｃ-ｄ）を、１０ｂ
は正常画素における液晶印可電圧（Ｖｌｃ-ｎ）を示
す。図中の実線は正常画素における電圧波形を、点線は
欠陥画素における電圧波形を表す。FIG. 4 shows a drive voltage waveform of a conventional TFT type liquid crystal display panel. Reference numerals 6a and 11b respectively indicate an ON voltage (VgH) and an OFF voltage (VgL) of the gate electrode, 7 is a source voltage (Vsig), and 8 is a counter voltage (Vc).
om), 9 is the drain voltage (Vp), and 10 is the liquid crystal applied voltage (Vlc). Here, 9a indicates the drain voltage (Vp-d) in the defective pixel, and 9b indicates the drain voltage (Vp-n) in the normal pixel. Further, 10a is the liquid crystal application voltage (Vlc-d) in the defective pixel, which is 10b.
Indicates a liquid crystal application voltage (Vlc-n) in a normal pixel. The solid line in the figure shows the voltage waveform in the normal pixel, and the dotted line shows the voltage waveform in the defective pixel.
【０００４】図５は、従来のＴＦＴ型液晶表示パネル
の、視野角方向のコントラスト分布特性を示す。この場
合、使用する位相差フィルムは、フィルム光軸と平行、
垂直あるいはフィルム膜厚方位における屈折率をそれぞ
れＮｘ、Ｎｙ、Ｎｚ、フィルム膜厚をＤとすると（Ｎｘ
−Ｎｚ）／（Ｎｘ−Ｎｙ）×Ｄ（以下、Ｒｔｈと定義す
る）で表されるリタデーションが、Ｒｔｈ≧１２０ｎｍ
以上のものを用いており、図５に示すような広視野角化
を実現している。FIG. 5 shows the contrast distribution characteristics of the conventional TFT type liquid crystal display panel in the viewing angle direction. In this case, the retardation film used is parallel to the optical axis of the film,
Let Nx, Ny, and Nz be the refractive indices in the vertical direction or the film thickness direction, and D be the film thickness (Nx
The retardation represented by −Nz) / (Nx−Ny) × D (hereinafter, defined as Rth) is Rth ≧ 120 nm.
By using the above components, a wide viewing angle as shown in FIG. 5 is realized.
【０００５】図６は、従来のＴＦＴ型液晶表示パネルの
欠陥画素及び正常画素の上下視角方向における電圧−輝
度特性を示す。ここで、欠陥画素とは、有効表示領域の
画素ピクセルのなかでも、ドレイン電極とそのドレイン
電極を上下に挟んで構成される当段もしくは前段のゲー
ト電極との電気的ショートによって生じる点欠陥を表
す。図６は、正常画素が黒表示状態のときの特性を示し
ている。この結果から明らかなように、黒表示状態では
視角が大きくなるに従い、欠陥画素の輝度が正常画素に
比べて大きく変化してしまうために画像表示上、薄輝点
状に認識されてしまい、高い表示品質を保つことが難し
かった。FIG. 6 shows the voltage-luminance characteristics in the vertical viewing angle direction of defective pixels and normal pixels of a conventional TFT type liquid crystal display panel. Here, the defective pixel means a point defect caused by an electrical short circuit between the drain electrode and the gate electrode at the current stage or the previous stage which is formed by vertically sandwiching the drain electrode among the pixel pixels in the effective display region. . FIG. 6 shows characteristics when normal pixels are in a black display state. As is clear from this result, in the black display state, as the viewing angle becomes larger, the luminance of the defective pixel greatly changes as compared with the normal pixel, so that it is recognized as a thin bright spot on the image display, which is high. It was difficult to maintain the display quality.
【０００６】[0006]
【発明が解決しようとする課題】しかし、近年、液晶デ
ィスプレイ（Ｌｉｑｕｉｄ Ｃｒｙｓｔａｌ Ｄｉｓｐ
ｌａｙ、以下ＬＣＤと略称する）は大型高精細へ加速化
すると同時に、高輝度、高色再現、高速応答技術の向上
からＣＲＴ並の優れた表示性能を実現しつつある。特
に、従来までＬＣＤの最重点課題であった視野角は、新
規な光学材料の開発及びセルプロセス技術の改善によっ
て、もはや実用上問題ないレベルにまで達している。今
後は、デジタル社会を想定した文字動画対応のマルチメ
ディア・ディスプレイとして、表示性能及び更なる高表
示品質が求められるものと期待される。[SUMMARY OF THE INVENTION] However, in recent years, liquid crystal display (L iquid C rystal D isp
(Lay, hereinafter abbreviated as LCD) is accelerating to large size and high definition, and at the same time, it is realizing excellent display performance comparable to that of CRT due to improvement of high brightness, high color reproduction and high speed response technology. In particular, the viewing angle, which has hitherto been the most important issue for LCDs, has reached a level where there is no practical problem due to the development of new optical materials and the improvement of cell process technology. In the future, it is expected that display performance and higher display quality will be required as a multimedia display that supports text and animation for the digital society.
【０００７】一方、ＬＣＤの製造プロセスの都合上、未
だ完全に克服できない課題に画素欠陥（輝点や黒点）が
上げられるが、特に、輝点はＬＣＤの表示品位を著しく
損なうために、画面表示上目立ちにくい黒点化処理にて
回避を図っていた。しかし、ＬＣＤの広視野角化、高コ
ントラスト化が強く望まれるケースでは、ＬＣＤのパネ
ル構成上、光学位相差フィルムが必要となるが、前記の
黒点画素は位相差フィルムとの光学補償が必ずしも成り
立たず、かえって薄輝点状に認識されてしまう問題を生
じていた。On the other hand, due to the LCD manufacturing process, pixel defects (bright spots and black spots) can be raised as a problem that cannot be completely overcome. Especially, since the bright spots significantly impair the display quality of the LCD, the screen display is difficult. I tried to avoid it by making black dots that are not noticeable. However, in the case where a wide viewing angle and a high contrast of the LCD are strongly desired, an optical retardation film is required due to the panel structure of the LCD, but the black dot pixels are not necessarily optically compensated with the retardation film. On the contrary, there was a problem that they were recognized as thin bright spots.
【０００８】そこで、本発明は、ツイストネマチック
（Ｔｗｉｓｔ Ｎｅｍａｔｉｃ）型の液晶表示パネルに
おいて、位相差フィルムによる広視野角化を図りつつ
も、黒点の薄輝点表示の課題を克服することで、画素欠
陥の目立ちにくい高表示品質な液晶表示パネルを提供す
る。[0008] Therefore, the present invention provides a twisted nematic (T wist N ematic) type liquid crystal display panel, even while achieving a wide viewing angle by the retardation film, to overcome the problem of display thin bright spot black spots Provide a liquid crystal display panel with high display quality in which pixel defects are less noticeable.
【０００９】[0009]
【課題を解決するための手段】前記課題を解決するた
め、本発明の薄膜トランジスタ型液晶表示パネルは、薄
膜トランジスタアレイ群を有する薄膜トタンジスタ基板
と透明電極を有する対向電極基板との間で、ネマチック
液晶がツイスト配列を成し、位相差フィルム及びクロス
ニコル偏光板の光学軸を、それぞれ前記薄膜トランジス
ト基板及び前記対向電極基板のラビング方位と同方位と
なるように構成した薄膜トランジスタ型液晶表示パネル
であって、欠陥画素の液晶印加電圧と正常画素の液晶印
加電圧とが等しくなるように、前記欠陥画素と導通する
ゲート電極のオフ電圧を制御することを特徴とする。In order to solve the above problems, a thin film transistor type liquid crystal display panel according to the present invention has a nematic liquid crystal between a thin film transistor substrate having a thin film transistor array group and a counter electrode substrate having a transparent electrode. A thin film transistor type liquid crystal display panel having a twisted array, wherein the optical axes of the retardation film and the crossed Nicols polarizing plate are respectively configured to have the same orientation as the rubbing orientation of the thin film transistor substrate and the counter electrode substrate, It is characterized in that the off-voltage of the gate electrode conducting with the defective pixel is controlled so that the liquid crystal applied voltage of the defective pixel becomes equal to the liquid crystal applied voltage of the normal pixel.
【００１０】また、本発明の薄膜トランジスタ型液晶表
示パネルにおいては、前記位相差フィルムの光学軸と平
行、垂直あるいはフィルム膜厚方位における屈折率をそ
れぞれＮｘ、Ｎｙ、Ｎｚ、前記位相差フィルム膜厚をＤ
としたときに、（Ｎｘ−Ｎｚ）／（Ｎｘ−Ｎｙ）×Ｄで
表される値が１２０ｎｍ以上であることが好ましい。In the thin film transistor type liquid crystal display panel of the present invention, the refractive index in the direction parallel to, perpendicular to, or in the film thickness direction of the retardation film is Nx, Ny, Nz, and the film thickness of the retardation film, respectively. D
Then, the value represented by (Nx-Nz) / (Nx-Ny) * D is preferably 120 nm or more.
【００１１】また、本発明の薄膜トランジスタ型液晶表
示パネルにおいては、前記欠陥画素が、有効表示画素の
ドレイン電極と、該電極と当段もしくは前段のゲート電
極間の電気的ショートによって生じるものであることが
好ましい。Further, in the thin film transistor type liquid crystal display panel of the present invention, the defective pixel is caused by an electric short circuit between the drain electrode of the effective display pixel and the gate electrode of the current stage or the previous stage. Is preferred.
【００１２】すなわち、本発明のＴＦＴ型液晶表示パネ
ルは、有効表示画素におけるドレイン電極とその当段ま
たは前段のゲート電極との電気的ショートで生じる欠陥
画素の液晶印可電圧と、正常画素の液晶印可電圧が等し
くなるように、欠陥画素と導通するゲート電極のＯＦＦ
電圧を調整するとともに、正常画素におけるゲート電極
のＯＦＦ電圧も同電圧に調整される走査駆動を用いたも
のである。本発明によれば、薄膜トランジスタ型液晶表
示パネルの点欠陥画素に対する光学補償ズレを、駆動電
圧で制御することで、画素欠陥の目立ちにくい高表示品
位なＴＦＴ型液晶表示パネルを得られる。That is, in the TFT type liquid crystal display panel of the present invention, the liquid crystal application voltage of the defective pixel and the liquid crystal application of the normal pixel caused by the electrical short circuit between the drain electrode and the gate electrode at the current stage or the previous stage in the effective display pixel. Turn off the gate electrode that conducts with the defective pixel so that the voltages become equal.
The scanning drive is used in which the OFF voltage of the gate electrode in a normal pixel is adjusted to the same voltage as the voltage is adjusted. According to the present invention, a TFT type liquid crystal display panel of high display quality in which pixel defects are less noticeable can be obtained by controlling the optical compensation shift for point defective pixels of the thin film transistor type liquid crystal display panel by the drive voltage.
【００１３】[0013]
【発明の実施の形態】本発明のＴＦＴ型液晶表示パネル
は、ＴＦＴ基板と対向電極基板との間でネマチック液晶
がツイスト配列を成し、両基板のラビング方位と同方位
に光学軸を揃えた位相差フィルム及びクロスニコル偏光
板で構成され、有効表示画素のドレイン電極とその当段
もしくは前段のゲート電極間の電気的ショートによって
生じる欠陥画素に対して、その欠陥画素と導通するゲー
ト電極のＯＦＦ電圧を、その欠陥画素の液晶に印加され
る電圧と正常画素の液晶に印加される電圧とが等しくな
るように調整するとともに、正常画素のゲートＯＦＦ電
圧も同電圧に調整されるようにしたものである。また、
位相差フィルムは、位相差フィルムの光学軸と平行、垂
直あるいは膜厚方位の屈折率をそれぞれＮｘ、Ｎｙ、Ｎ
ｚとし、フィルム膜厚をＤで表した場合、（Ｎｘ−Ｎ
ｚ）／（Ｎｘ−Ｎｙ）×Ｄ値が１２０ｎｍ以上を満足す
るものである。BEST MODE FOR CARRYING OUT THE INVENTION In the TFT type liquid crystal display panel of the present invention, nematic liquid crystal is twisted between the TFT substrate and the counter electrode substrate, and the optical axes are aligned in the same direction as the rubbing direction of both substrates. For a defective pixel that is composed of a retardation film and a crossed Nicols polarizing plate and is caused by an electrical short circuit between the drain electrode of the effective display pixel and the gate electrode at the current stage or the previous stage, the gate electrode that is in conduction with the defective pixel is turned off. The voltage is adjusted so that the voltage applied to the liquid crystal of the defective pixel is equal to the voltage applied to the liquid crystal of the normal pixel, and the gate OFF voltage of the normal pixel is also adjusted to the same voltage. Is. Also,
The retardation film has a refractive index parallel to the optical axis of the retardation film, perpendicular to the optical axis, or in the film thickness direction of Nx, Ny, and N, respectively.
z and the film thickness is represented by D, (Nx-N
z) / (Nx−Ny) × D value satisfies 120 nm or more.
【００１４】この構成によると、黒表示状態において黒
点画素の液晶層と位相差フィルムとの光学補償ズレを回
避することができ、いずれの視野角方向から表示画面を
眺めても正常画素との輝度差が生じないために薄輝点と
なって見えず、良好な画像表示を実現することができ
る。According to this structure, it is possible to avoid the optical compensation shift between the liquid crystal layer of the black dot pixel and the retardation film in the black display state, and the brightness of the normal pixel is observed regardless of the viewing angle direction. Since there is no difference, it does not appear as a bright spot and a good image display can be realized.
【００１５】以下、本発明の実施の形態について説明す
る。Embodiments of the present invention will be described below.
【００１６】（実施の形態１）図１は、本発明のＴＦＴ
型液晶表示パネルの駆動電圧波形を示す。６ａ、６ｂは
それぞれ欠陥画素及び正常画素のゲート電極のＯＮ電圧
（ＶｇＨ）を示す。また、１１ａ、１１ｂはそれぞれ欠
陥画素及び正常画素のゲート電極のＯＦＦ電圧（Ｖｇ
Ｌ）を示す。ここで、欠陥画素の６ａは正常画素の６ｂ
と同電位であってもかまわない。７はソース電圧（Ｖｓ
ｉｇ）、８は対向電圧（Ｖｃｏｍ）を示す。また、１２
ｂは正常画素のドレイン電圧（Ｖｐ-ｎ）、１２ａは欠
陥画素のドレイン電圧（Ｖｐ-ｄ）及び１３ｂは正常画
素の液晶印加電圧（Ｖｌｃ-ｎ）、１３ａは欠陥画素の
液晶印加電圧（Ｖｌｃ-ｄ）を示す。図１に示すよう
に、欠陥画素のドレイン電圧（１２ａ）と対向電圧
（８）との電圧差、すなわち液晶印可電圧（１３ａ）が
正常画素の１３ｂと等しくなるように欠陥画素のゲート
ＯＦＦ電圧（１１ａ）を調整した。また、本発明のＴＦ
Ｔ型液晶表示パネル構成は、従来の液晶表示パネルと同
構成とした。(Embodiment 1) FIG. 1 shows a TFT of the present invention.
7 shows a drive voltage waveform of a liquid crystal display panel of the type. Reference numerals 6a and 6b denote ON voltages (VgH) of the gate electrodes of the defective pixel and the normal pixel, respectively. Further, 11a and 11b are the OFF voltage (Vg) of the gate electrodes of the defective pixel and the normal pixel, respectively.
L) is shown. Here, the defective pixel 6a is a normal pixel 6b.
It does not matter even if it is the same potential as. 7 is the source voltage (Vs
ig) and 8 indicate the counter voltage (Vcom). Also, 12
b is the drain voltage (Vp-n) of the normal pixel, 12a is the drain voltage (Vp-d) of the defective pixel, 13b is the liquid crystal applied voltage (Vlc-n) of the normal pixel, and 13a is the liquid crystal applied voltage (Vlc) of the defective pixel. -d) is shown. As shown in FIG. 1, the gate-off voltage of the defective pixel is set so that the voltage difference between the drain voltage (12a) of the defective pixel and the counter voltage (8), that is, the liquid crystal applied voltage (13a) becomes equal to 13b of the normal pixel. 11a) was prepared. Further, the TF of the present invention
The configuration of the T-type liquid crystal display panel was the same as that of the conventional liquid crystal display panel.
【００１７】図２は、欠陥画素及び正常画素の上下視角
方向での視角−輝度特性を示す。但し、正常画素は黒表
示状態における特性を示している。この結果から明らか
なように、黒表示状態では欠陥画素と正常画素の視角−
輝度特性はほぼ同特性となり、画像表示上両者を識別で
きなくなり、欠陥画素の薄輝点課題を回避できることが
わかる。ここで、欠陥画素の前記特性を、正常画素の黒
表示状態で調整する理由は、階調表示上、最も欠陥画素
が目立ちにくい画像表示とするためであるが、必ずしも
黒表示での階調である必然性はなく、その他の階調レベ
ルで１１ｂの調整を行ってもかまわない。FIG. 2 shows the viewing angle-luminance characteristics of the defective pixel and the normal pixel in the vertical viewing angle direction. However, the normal pixel shows the characteristic in the black display state. As is clear from this result, in the black display state, the viewing angle between the defective pixel and the normal pixel is −
It can be seen that the luminance characteristics are almost the same, the two cannot be distinguished on the image display, and the problem of the thin bright spot of the defective pixel can be avoided. Here, the reason why the characteristic of the defective pixel is adjusted in the black display state of the normal pixel is to make the image display in which the defective pixel is the most inconspicuous in gradation display. There is no necessity, and 11b may be adjusted at other gradation levels.
【００１８】[0018]
【実施例】以下、実施例により本発明を具体的に説明す
る。EXAMPLES The present invention will be specifically described below with reference to examples.
【００１９】（実施例１）液晶パネルの構成は、液晶の
セル厚（ｄ）をｄ＝４．７μｍ、液晶の屈折率異方性
（△ｎ）を△ｎ＝０．０８２（λ＝５５０ｎｍ）、誘電
率異方性（△ε）を△ε＝４．４、弾性定数Ｋ１１＝
９．２ｐＮ、Ｋ２２＝８．９ｐＮ、Ｋ３３＝２１．５ｐ
Ｎとなるものを用いた。また、ラビング処理における液
晶ツイスト角（θ）をθ＝９０゜に調整した。一方、位
相差フィルムは、フィルムの光軸と平行、垂直及び膜厚
方位の屈折率をそれぞれＮｘ、Ｎｙ、Ｎｚとし、フィル
ム膜厚をＤとしたときに、（Ｎｘ−Ｎｚ）／（Ｎｘ−Ｎ
ｙ）×Ｄの値が１２０ｎｍ以上となるものを用いた。ま
た、正常画素の黒表示での液晶印加電圧は約５Ｖとし、
欠陥画素及び正常画素のゲートオフ電圧を約−２．５Ｖ
に設定した。得られたＴＦＴ型液晶表示パネルの表示特
性を図２に示す。(Embodiment 1) The constitution of the liquid crystal panel is as follows. The cell thickness (d) of the liquid crystal is d = 4.7 μm, and the refractive index anisotropy (Δn) of the liquid crystal is Δn = 0.082 (λ = 550 nm). ), Dielectric anisotropy (Δε) is Δε = 4.4, and elastic constant K11 =
9.2pN, K22 = 8.9pN, K33 = 21.5p
The one with N was used. Further, the liquid crystal twist angle (θ) in the rubbing treatment was adjusted to θ = 90 °. On the other hand, the retardation film is (Nx−Nz) / (Nx−), where Nx, Ny, and Nz are the refractive indices in the parallel, vertical, and film thickness directions, respectively, and the film thickness is D. N
The value of y) × D was 120 nm or more. Also, the liquid crystal applied voltage for black display of normal pixels is about 5V,
Gate-off voltage of defective pixel and normal pixel is about -2.5V
Set to. The display characteristics of the obtained TFT type liquid crystal display panel are shown in FIG.
【００２０】図２の結果から明らかなように、欠陥画素
と正常画素とでなんら特性上に違いがなく、従来生じた
欠陥画素部の薄輝点といった問題のない、高品質な画像
表示を提供することができた。As is clear from the results shown in FIG. 2, there is no difference in characteristics between the defective pixel and the normal pixel, and there is provided a high-quality image display without the problem such as the thin bright spot of the defective pixel portion which has been generated conventionally. We were able to.
【００２１】[0021]
【発明の効果】以上のように、本発明のＴＦＴ型液晶表
示パネルによれば、ＴＦＴ基板と対向電極基板からなる
ＴＮ型液晶パネルで、両基板のラビング方位と同方位に
光学軸を揃えた位相差フィルム及びクロスニコル偏光板
より構成されるとともに、画素のドレイン電極とその当
段もしくは前段のゲート電極間で電気的ショートで生じ
る欠陥画素と正常画素の液晶に印可される電圧が等しく
なるように欠陥画素と導通するゲート電極のオフ電圧を
制御するとともに、正常画素のゲートオフ電圧も同電圧
に調整されており、且つ位相差フィルムの厚み方向にお
けるリタデーション（Ｒｔｈ）がＲｔｈ≧１２０ｎｍを
満足するフィルム構成を用いたので、欠陥画素と正常画
素との黒表示状態における光学補償ズレを回避すること
ができ、いずれの視角方向から眺めても両者に透過率差
が生じず、画像表示上コントラスト差となって現れない
ため、広視野角で高品位なえ液晶画像表示を提供するこ
とができる。よって、その工業的価値は大である。As described above, according to the TFT type liquid crystal display panel of the present invention, in the TN type liquid crystal panel comprising the TFT substrate and the counter electrode substrate, the optical axes are aligned in the same direction as the rubbing direction of both substrates. It is composed of a retardation film and a crossed Nicol polarizing plate, and the voltage applied to the liquid crystal of a normal pixel and the defective pixel caused by an electrical short circuit between the drain electrode of the pixel and the gate electrode of the current stage or the previous stage are equalized. In addition to controlling the off-voltage of the gate electrode conducting to the defective pixel, the gate-off voltage of the normal pixel is adjusted to the same voltage, and the retardation (Rth) in the thickness direction of the retardation film satisfies Rth ≧ 120 nm. Since the configuration is used, it is possible to avoid the optical compensation shift in the black display state between the defective pixel and the normal pixel. Transmittance difference does not occur between them even looking from the corner direction, because no appear as image display on the contrast difference, it is possible to provide a high-quality withered liquid crystal image display with a wide viewing angle. Therefore, its industrial value is great.
【図１】本発明の薄膜トランジスタ型液晶表示パネルの
駆動電圧波形図である。FIG. 1 is a drive voltage waveform diagram of a thin film transistor type liquid crystal display panel of the present invention.
【図２】本発明の実施の形態１における視角−輝度特性
図である。FIG. 2 is a view angle-luminance characteristic diagram in the first embodiment of the present invention.
【図３】従来の薄膜トランジスタ型液晶表示パネルの斜
視外観図である。FIG. 3 is a perspective external view of a conventional thin film transistor type liquid crystal display panel.
【図４】従来の薄膜トランジスタ型液晶表示パネルの駆
動電圧波形図である。FIG. 4 is a drive voltage waveform diagram of a conventional thin film transistor type liquid crystal display panel.
【図５】従来の薄膜トランジスタ型液晶表示パネルの視
野角方向のコントラスト分布図である。FIG. 5 is a contrast distribution diagram in the viewing angle direction of a conventional thin film transistor type liquid crystal display panel.
【図６】従来の薄膜トランジスタ型液晶表示パネルの視
角−輝度特性図である。FIG. 6 is a view angle-luminance characteristic diagram of a conventional thin film transistor type liquid crystal display panel.
１ ＴＦＴ基板〔薄膜トランジスタ基板〕 ２ 対向電極基板 ６，１１ ゲート電圧 ７ ソース電圧 ８ 対向電圧 ９，１２ ドレイン電圧 １０，１３ 液晶印加電圧 １４ 位相差フィルム １５ 偏光板 １６ 液晶 1 TFT substrate [thin film transistor substrate] 2 Counter electrode substrate 6,11 Gate voltage 7 Source voltage 8 Opposite voltage 9,12 drain voltage 10, 13 Liquid crystal applied voltage 14 Phase difference film 15 Polarizer 16 liquid crystal
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｇ０９Ｇ 3/20 ６７０ Ｇ０９Ｇ 3/20 ６７０Ａ 3/36 3/36 Ｆターム(参考） 2H091 FA08X FA08Z FA11X FA11Z FD08 FD09 FD10 GA13 HA07 KA02 KA03 LA17 LA19 2H093 NA16 NA79 NB01 NB30 NC34 ND05 ND09 ND13 ND58 NF05 NH01 NH12 5C006 AA01 AA02 AA16 AC11 AF42 AF52 AF75 BB16 BC03 BF42 EB04 FA20 FA22 FA25 FA55 FA56 GA04 5C080 AA10 BB05 DD05 DD28 EE01 EE19 EE29 FF03 FF11 GG08 JJ04 JJ05 JJ06 KK02 KK43─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. 7 Identification code FI theme code (reference) G09G 3/20 670 G09G 3/20 670A 3/36 3/36 F term (reference) 2H091 FA08X FA08Z FA11X FA11Z FD08 FD09 FD10 GA13 HA07 KA02 KA03 LA17 LA19 2H093 NA16 NA79 NB01 NB30 NC34 ND05 ND09 ND13 ND58 NF05 NH01 NH12 5C006 AA01 AA02 AA16 AC11 AF42 AF52 AF75 WD1629 JJ04 JJ05 JJ06 KK02 KK43
Claims (3)
トタンジスタ基板と透明電極を有する対向電極基板との
間で、ネマチック液晶がツイスト配列を成し、位相差フ
ィルム及びクロスニコル偏光板の光学軸を、それぞれ前
記薄膜トランジスト基板及び前記対向電極基板のラビン
グ方位と同方位となるように構成した薄膜トランジスタ
型液晶表示パネルであって、 欠陥画素の液晶印加電圧と正常画素の液晶印加電圧とが
等しくなるように、前記欠陥画素と導通するゲート電極
のオフ電圧を制御することを特徴とする薄膜トランジス
タ型液晶表示パネル。1. A nematic liquid crystal forms a twist arrangement between a thin film transistor substrate having a thin film transistor array group and a counter electrode substrate having a transparent electrode, and the optical axes of a retardation film and a crossed Nicols polarizing plate are respectively defined as described above. A thin film transistor type liquid crystal display panel configured to have the same orientation as the rubbing orientation of a thin film transistor substrate and the counter electrode substrate, wherein the liquid crystal applied voltage of a defective pixel and the liquid crystal applied voltage of a normal pixel are equal to each other. A thin film transistor type liquid crystal display panel characterized by controlling an off-voltage of a gate electrode which is electrically connected to a defective pixel.
直あるいはフィルム膜厚方位における屈折率をそれぞれ
Ｎｘ、Ｎｙ、Ｎｚ、前記位相差フィルム膜厚をＤとした
ときに、（Ｎｘ−Ｎｚ）／（Ｎｘ−Ｎｙ）×Ｄで表され
る値が１２０ｎｍ以上である請求項１に記載の薄膜トラ
ンジスタ型液晶表示パネル。2. When Nx, Ny, and Nz are the refractive indices in parallel, perpendicular to the optical axis of the retardation film, or in the film thickness direction, and D is the retardation film thickness, (Nx-Nz). The thin film transistor type liquid crystal display panel according to claim 1, wherein a value represented by / (Nx-Ny) * D is 120 nm or more.
ン電極と、該電極と当段もしくは前段のゲート電極間の
電気的ショートによって生じるものである請求項１又は
２に記載の薄膜トランジスタ型液晶表示パネル。3. The thin film transistor type liquid crystal display according to claim 1, wherein the defective pixel is caused by an electrical short circuit between the drain electrode of the effective display pixel and the gate electrode at the current stage or the previous stage. panel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002022213A JP2003222837A (en) | 2002-01-30 | 2002-01-30 | Thin film transistor type liquid crystal display panel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002022213A JP2003222837A (en) | 2002-01-30 | 2002-01-30 | Thin film transistor type liquid crystal display panel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003222837A true JP2003222837A (en) | 2003-08-08 |
Family
ID=27745258
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002022213A Withdrawn JP2003222837A (en) | 2002-01-30 | 2002-01-30 | Thin film transistor type liquid crystal display panel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003222837A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102455538A (en) * | 2010-11-04 | 2012-05-16 | 三星移动显示器株式会社 | Liquid crystal display with integrated touch screen panel |
| WO2014203366A1 (en) * | 2013-06-20 | 2014-12-24 | 三菱電機株式会社 | Image processing device, method, and program, and image display device |
-
2002
- 2002-01-30 JP JP2002022213A patent/JP2003222837A/en not_active Withdrawn
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102455538A (en) * | 2010-11-04 | 2012-05-16 | 三星移动显示器株式会社 | Liquid crystal display with integrated touch screen panel |
| WO2014203366A1 (en) * | 2013-06-20 | 2014-12-24 | 三菱電機株式会社 | Image processing device, method, and program, and image display device |
| CN105324808A (en) * | 2013-06-20 | 2016-02-10 | 三菱电机株式会社 | Image processing device, method, and program, and image display device |
| US9779651B2 (en) | 2013-06-20 | 2017-10-03 | Mitsubishi Electric Corporation | Image processing device, method, and program, and image display device |
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