JPS6112786A - Liquid crystal display device - Google Patents
Liquid crystal display deviceInfo
- Publication number
- JPS6112786A JPS6112786A JP13112784A JP13112784A JPS6112786A JP S6112786 A JPS6112786 A JP S6112786A JP 13112784 A JP13112784 A JP 13112784A JP 13112784 A JP13112784 A JP 13112784A JP S6112786 A JPS6112786 A JP S6112786A
- Authority
- JP
- Japan
- Prior art keywords
- liquid crystal
- crystal display
- display device
- dielectric anisotropy
- liquid crystals
- 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.)
- Granted
Links
Landscapes
- Liquid Crystal (AREA)
- Liquid Crystal Substances (AREA)
Abstract
Description
【発明の詳細な説明】 〔発明の技術分野〕 本発明は液晶表示装置の改良に関する。[Detailed description of the invention] [Technical field of invention] The present invention relates to improvements in liquid crystal display devices.
液晶表示装置は対向する対をなす電極基板に液晶を挾持
し、た液晶表示器と、この表示器の電極に電圧を印加す
るための駆動回路とからなり、駆動回路からの電圧によ
り電極間の液晶の配向を変え々の工夫がなされるが、多
種の液晶を混合するのもその一つである。例えば液晶表
示の使用温度範囲を広げるため、表示の応答性をめげる
ため、閾値電圧のコントロール、印加電圧に対テる透過
率の変化の急峻度の向上のため等を目的として正の誘電
異方性を有する単体液晶と負の誘電異方性を有する単体
液晶とをそれぞれ複数種混合した液晶が用いられる。A liquid crystal display device consists of a liquid crystal display device in which a liquid crystal is sandwiched between a pair of electrode substrates facing each other, and a drive circuit for applying voltage to the electrodes of this display device. Various attempts have been made to change the orientation of liquid crystals, one of which is to mix various types of liquid crystals. For example, positive dielectric anisotropy is used to expand the operating temperature range of liquid crystal displays, to reduce display responsiveness, to control threshold voltage, to improve the steepness of changes in transmittance with respect to applied voltage, etc. A liquid crystal obtained by mixing a plurality of types of single liquid crystals having dielectric properties and single liquid crystals having negative dielectric anisotropy is used.
一方、液晶の表示方式にはスタティック方式と時分割駆
動方式があるが、表示容量を多くするためｖｃは時分割
駆動方式が採用される。On the other hand, liquid crystal display methods include a static method and a time-division drive method, but the time-division drive method is adopted for VC in order to increase the display capacity.
時分割駆動方式をＸＹマトリクス表示を例にして説明す
る。複数のＹ％極を走査電極、Ｘｍ極をデータ電極とす
ると、線順次で走査される走査電極の電圧は第８図のよ
うな波形で示される。図においてＡは選択期間、Ｂは非
選択期間で、選択期間にはｂｖｂの電圧、非選択期間に
Ｖｉｖｂの電圧がそれぞれ印加される。ここでｖｂは電
圧平均化法によって求められるバイアス電圧である。The time division driving method will be explained using an XY matrix display as an example. When a plurality of Y% poles are used as scan electrodes and the Xm poles are used as data electrodes, the voltage of the scan electrodes scanned line-sequentially is shown by a waveform as shown in FIG. In the figure, A is a selection period and B is a non-selection period, and the voltage bvb is applied during the selection period, and the voltage Vivb is applied during the non-selection period. Here, vb is a bias voltage determined by the voltage averaging method.
一方データ電極には表示の内容によるデータの信号電圧
が印加される。以上により形成される走査電極波形とデ
ータ電極波形の合成波形が両電極の交点に印加され表示
が行われる。On the other hand, a data signal voltage depending on the display content is applied to the data electrode. A composite waveform of the scanning electrode waveform and the data electrode waveform formed as described above is applied to the intersection of both electrodes to perform display.
さて時分割数が多くなると種々の問題が発生する。発明
者等は時分割数を３２．６４，１２８．・・・・・と増
加するとある種の表示むら現象が生じることを見出した
。Now, when the number of time divisions increases, various problems occur. The inventors set the number of time divisions to 32.64, 128. It has been found that when the value increases, a certain kind of display unevenness phenomenon occurs.
第９図はこの表示むら現象を説明する図である。FIG. 9 is a diagram illustrating this display unevenness phenomenon.
ａはＡ、Ｂ、０の文字表示が行われている領域、ｂは表
示のない領域である。このような表示において時分割数
Ｎを増７１０してぃくと、ａ列の下方で表示のない領域
Ｃの輝度はａ、ａ間ＶＣある表示のない領域すの輝度よ
りも高くなる表示むら現象が生じる。この現象は表示品
位を低下させるものであシ解決しなければならない課題
である。A is an area where characters A, B, and 0 are displayed, and b is an area where no characters are displayed. In such a display, when the number of time divisions N is increased by 710, the brightness of the area C where there is no display below the a column becomes higher than the brightness of the area C where there is no display between a and a. A phenomenon occurs. This phenomenon degrades display quality and is a problem that must be solved.
本発明は上記課題を解決するためになされたもので、時
分割数が増大しても表示むら現象が生じない表示品位の
よい液晶表示装置を提供することを目的とする。The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a liquid crystal display device with good display quality that does not cause display unevenness even when the number of time divisions increases.
発明者等は本課題を解決するために多くの実験を行う中
で、表示むら現象をなくすためには、正の誘電異方性を
有する液晶のうち、駆動回路のバイアス電圧より小さい
閾値電圧を有する単体液晶の比率に関係していることを
見出した。第１図はこの実験結果を説明する図で、横軸
は正の誘電異方性を有する液晶のうち駆動回路のパ・イ
アスミ圧より小ざい閾値電圧を有する単体液晶の混晶混
合物全体に対する重量比で表わした値、縦軸は表示むら
現象の度合い（第９図におけるａの下方の表示のない領
域の輝度と、ｂの領域の輝度の比）を示すもので、実用
面から判断すると破線以上が不」・入
良領域、実線や下が非常によい長域である。本発明はこ
の結果に基づいてなされたものでらる。The inventors conducted many experiments to solve this problem, and found that in order to eliminate the display unevenness phenomenon, a liquid crystal with positive dielectric anisotropy with a threshold voltage lower than the bias voltage of the drive circuit was used. It was found that this is related to the ratio of single liquid crystals. Figure 1 is a diagram explaining the results of this experiment, where the horizontal axis shows the weight of a single liquid crystal with positive dielectric anisotropy, which has a threshold voltage smaller than the piezoelectric pressure of the drive circuit, relative to the entire mixed crystal mixture. The value expressed as a ratio, and the vertical axis indicates the degree of display unevenness (the ratio of the brightness of the area with no display below a in Fig. 9 and the brightness of the area b), and from a practical point of view, the broken line The above is a bad/good range, and the solid line or below is a very good long range. The present invention has been made based on this result.
すなわち本発明は、正の誘電異方性を有する単体液晶を
複数種と、負の誘電異方性を有する単体液晶を複数種混
合した混合液晶を２枚の電極基板間に挾持してなる液晶
表示器と、この液晶表示器を時分割部゛動する駆動回路
とを具備する液晶表示装置において、前記正の誘電異方
性を有する液晶のうち、前記駆動回路のバイアス電圧よ
り小さい閾値電圧を有する単体液晶の比率は、液晶混合
物の２０重量係以下であることを特徴とする液晶表示装
置である。That is, the present invention provides a liquid crystal in which a mixed liquid crystal, which is a mixture of multiple types of single liquid crystals having positive dielectric anisotropy and multiple types of single liquid crystals having negative dielectric anisotropy, is sandwiched between two electrode substrates. In a liquid crystal display device comprising a display device and a drive circuit for driving the liquid crystal display device in a time division manner, a threshold voltage of the liquid crystal having positive dielectric anisotropy that is lower than a bias voltage of the drive circuit is provided. The liquid crystal display device is characterized in that the proportion of the single liquid crystal contained in the liquid crystal mixture is 20% by weight or less of the liquid crystal mixture.
実施例に用いた闇値電圧がバイアス電圧より高い液晶を
混合した混合液晶Ａ及びＢの混合内容を表１に示す。Table 1 shows the contents of mixed liquid crystals A and B used in the examples, in which liquid crystals having a dark value voltage higher than the bias voltage were mixed.
Ａ又はＢに添加混合される正の誘電異方性を有する液晶
であって、バイアス電圧より小ざい閾値電圧を有する単
体液晶ＥＣ，ＣＤ、ＤＰＥ３種類の内容を表２に示す。Table 2 shows the contents of three types of single liquid crystals EC, CD, and DPE, which are liquid crystals having positive dielectric anisotropy and having a threshold voltage smaller than the bias voltage, which are added to A or B.
実施例１〜６においてＡ又はＢにＥＣ，ＣＤ又はＤＰＥ
を混合し、混合量を変えて表示むらの輝度比を測定し
た。このときの時分割数は６４である。In Examples 1 to 6, A or B is EC, CD or DPE.
were mixed, and the brightness ratio of display unevenness was measured by changing the mixing amount. The number of time divisions at this time is 64.
その結果を第２図〜第７図に示す。The results are shown in FIGS. 2 to 7.
図に示す通り閾値電圧の小さい単体液晶の混合比を増や
すと輝度比が高くなっており、混合比は２０重量−以下
が好ましいことがわかる。As shown in the figure, increasing the mixing ratio of single liquid crystals with small threshold voltages increases the brightness ratio, and it can be seen that the mixing ratio is preferably 20% by weight or less.
以上の実施例は時分割数が６４でらったが、時分割数を
３２〜１２８に変えてもほぼ同様な結果であったＯ
（以下余白）
表２In the above example, the number of time divisions was 64, but almost the same results were obtained even if the number of time divisions was changed from 32 to 128.
第１図〜第７図は本発明の詳細な説明する図、第８図は
時分割駆動方法ｒＣおける走査電極の電圧波形を示す図
、第９図は表示むら現象を説明する図である。
代理人 弁理士 則 近 憲 佑（ほか１名）第１図
ρ ｌρ ２’６ ３ρ ４．（％〕
第２図 第３図
Ｖム：１２〜ｒ、ｏｓ
Ｖｂ＝ｏ、ｑ〜／、ｔｔ！。
第４図 第５図
第６図 第７図
Ｖム＝ｔＺ−ｔＱＺ？ 、
Ｖｂ＝ｌｔρ−１，ｔ、ｙ第８図1 to 7 are diagrams explaining the present invention in detail, FIG. 8 is a diagram showing voltage waveforms of scanning electrodes in the time division driving method rC, and FIG. 9 is a diagram explaining display unevenness phenomenon. Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 ρ lρ 2'6 3ρ 4. (%) Figure 2 Figure 3 Vmu: 12~r, os
Vb=o, q~/, tt! . Figure 4 Figure 5 Figure 6 Figure 7 V = tZ - tQZ? ,
Vb=ltρ-1,t,yFigure 8
Claims (1)
誘電異方性を有する単体液晶を複数種混合した混合液晶
を２枚の電極基板間に挾持してなる液晶表示器と、この
液晶表示器を時分割駆動する駆動回路とを具備する液晶
表示装置において、前記正の誘電異方性を有する液晶の
うち、前記駆動回路のバイアス電圧より小さい閾値電圧
を有する単体液晶の比率は、液晶混合物の２０重量％以
下であることを特徴とする液晶表示装置。 ２、時分割数が３２以上であることを特徴とする特許請
求の範囲第１項記載の液晶表示装置。[Claims] 1. A mixed liquid crystal, which is a mixture of multiple types of single liquid crystals having positive dielectric anisotropy and multiple types of single liquid crystals having negative dielectric anisotropy, is sandwiched between two electrode substrates. A liquid crystal display device comprising a liquid crystal display comprising a liquid crystal display and a drive circuit that drives the liquid crystal display in a time division manner, wherein a threshold voltage of the liquid crystal having positive dielectric anisotropy is lower than a bias voltage of the drive circuit. A liquid crystal display device characterized in that the proportion of a single liquid crystal having a liquid crystal composition is 20% by weight or less of a liquid crystal mixture. 2. The liquid crystal display device according to claim 1, wherein the number of time divisions is 32 or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13112784A JPS6112786A (en) | 1984-06-27 | 1984-06-27 | Liquid crystal display device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13112784A JPS6112786A (en) | 1984-06-27 | 1984-06-27 | Liquid crystal display device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6112786A true JPS6112786A (en) | 1986-01-21 |
| JPH0578596B2 JPH0578596B2 (en) | 1993-10-29 |
Family
ID=15050612
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13112784A Granted JPS6112786A (en) | 1984-06-27 | 1984-06-27 | Liquid crystal display device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6112786A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5708046A (en) * | 1995-09-21 | 1998-01-13 | Dow Corning Corporation | Silicone release coating compostions |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5483694A (en) * | 1977-12-16 | 1979-07-03 | Hitachi Ltd | Nematic liquid crystal body for display device |
| JPS578281A (en) * | 1980-06-17 | 1982-01-16 | Mitsubishi Electric Corp | Nematic liquid crystal material for display device |
| JPS6013883A (en) * | 1983-07-04 | 1985-01-24 | Seiko Epson Corp | Liquid crystal composition and liquid crystal display |
-
1984
- 1984-06-27 JP JP13112784A patent/JPS6112786A/en active Granted
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5483694A (en) * | 1977-12-16 | 1979-07-03 | Hitachi Ltd | Nematic liquid crystal body for display device |
| US4372871A (en) * | 1977-12-16 | 1983-02-08 | Dainippon Ink And Chemicals, Inc. | Nematic liquid crystals for display devices |
| JPS578281A (en) * | 1980-06-17 | 1982-01-16 | Mitsubishi Electric Corp | Nematic liquid crystal material for display device |
| JPS6013883A (en) * | 1983-07-04 | 1985-01-24 | Seiko Epson Corp | Liquid crystal composition and liquid crystal display |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5708046A (en) * | 1995-09-21 | 1998-01-13 | Dow Corning Corporation | Silicone release coating compostions |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0578596B2 (en) | 1993-10-29 |
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