JPS6113225A - Liquid crystal light bulb - Google Patents
Liquid crystal light bulbInfo
- Publication number
- JPS6113225A JPS6113225A JP13430784A JP13430784A JPS6113225A JP S6113225 A JPS6113225 A JP S6113225A JP 13430784 A JP13430784 A JP 13430784A JP 13430784 A JP13430784 A JP 13430784A JP S6113225 A JPS6113225 A JP S6113225A
- Authority
- JP
- Japan
- Prior art keywords
- liquid crystal
- liq
- thin layer
- crystal
- electrode
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/141—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent using ferroelectric liquid crystals
Landscapes
- Physics & Mathematics (AREA)
- Liquid Crystal (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Nonlinear Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Liquid Crystal Substances (AREA)
Abstract
Description
【発明の詳細な説明】
（技術分野）
本発明は、レーザ熱書込み方式の液晶ライトパルプに関
する。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a liquid crystal light pulp using a laser thermal writing method.
（従来技術とその問題点）
ある種の液晶物質の薄層に、レーザ光を照射する等の手
段で部分的に加熱し急冷すると、その部分が光を散乱す
る不透明な液晶組織に遷移し、この状態で電界を印加す
ると元の透明な液晶組織に戻る現象が液晶の電気熱光学
効果として知られている。また、このような液晶物質の
薄層を電極を備えた二枚の相対向する基板で挾持した構
造の液晶ライトパルプに、レーザ光を儒択照射して、透
明な液晶組織の中に光散乱状態の液晶組織を作シ出すこ
とによって画像を書込み、この画像を投映用の光学系を
用いて拡大投写する方式の表示装置が知られている。こ
のような液晶の電気熱光学効果を応用した液晶ライトパ
ルプには、従来は実用的にはスメクティック液晶が用い
られていた。また、一方ではスメクティック液晶にコレ
ステリック液晶を混合することによシ、画像書込み速度
が速くなるとの実験報告が公知である（第５回液晶討論
会講演予稿集、第１７２−１７３頁、 １９７９年・１
０月）。しかしながら、この種のコレステリック液晶と
して報告されているものはコレステリルノナノエイトに
代表されるコレステロール誘導体構造の物質に限定され
ている。ところがコレステロール誘導体は製造上、精製
等の手法で純度を上げることが困難であシ、この種の物
質を混合した液晶物質は抵抗値が極端に低下し、液晶ラ
イトバルブに使用すると画像消去用の高電圧を印加した
場合に絶縁破壊によるショートが発生するという問題が
生じて実用化できないのが現状であった。(Prior art and its problems) When a thin layer of a certain type of liquid crystal material is partially heated by irradiating it with laser light and then rapidly cooled, that part transforms into an opaque liquid crystal structure that scatters light. When an electric field is applied in this state, the liquid crystal returns to its original transparent structure, which is known as the electrothermo-optic effect of liquid crystal. In addition, by selectively irradiating a liquid crystal light pulp with a structure in which a thin layer of liquid crystal material is sandwiched between two opposing substrates equipped with electrodes with laser light, light is scattered within the transparent liquid crystal structure. 2. Description of the Related Art A display device is known that writes an image by creating a liquid crystal structure of a state, and enlarges and projects the image using a projection optical system. Conventionally, smectic liquid crystals have been practically used for liquid crystal light pulp that utilizes the electrothermo-optical effect of liquid crystals. On the other hand, there is a known experimental report that the image writing speed increases by mixing cholesteric liquid crystal with smectic liquid crystal (Proceedings of the 5th Liquid Crystal Symposium, pp. 172-173, 1979). 1
(October). However, what has been reported as this type of cholesteric liquid crystal is limited to substances with a cholesterol derivative structure typified by cholesteryl nonanoate. However, it is difficult to increase the purity of cholesterol derivatives through purification and other methods during production, and liquid crystal materials mixed with this kind of substance have extremely low resistance values, and when used in liquid crystal light valves, it is difficult to increase the purity of cholesterol derivatives. The current situation is that when a high voltage is applied, a short circuit occurs due to dielectric breakdown, making it impossible to put it into practical use.
一方、コレステリック物質としてはコレステロール誘導
体の他に、カイラルネマティック材として公知の物質が
ｓｂ、この種の物質は高純度のものが得られることも知
られている。しかしながら、スメクティック液晶にカイ
ラルネマティック材を混合した混合液晶物質は基板に対
する界面配向状態を制御することが極めて困難であシ、
この界面配向状態が制御できないと液晶ライトパルプに
使用しても初期の透明な液晶組織が得られずに画像書込
みができないか、仮にできても表示コントラストが極め
て悪く実用に耐えないものしか得られなかった。このよ
うに、液晶ライトパルプの画像書込み速度を改善するた
めには、液晶物質とじてスメクティック液晶にコレステ
リック液晶を混合した液晶物質を用いると効果的である
ことが原理的には確認されていたものの、実用的には使
用できるコレステリック液晶が見出されずに具現化でき
ていないのが現状であった。しかるに本発明者は数多く
の液晶材料について実験評価し、液晶ライトパルプとし
て実用に耐え得る液晶材料と液晶ライトバルブ構成要件
とを見出して本発明に至ったものである。On the other hand, in addition to cholesterol derivatives, cholesteric substances include sb, a substance known as a chiral nematic material, and it is also known that this type of substance can be obtained with high purity. However, it is extremely difficult to control the interfacial alignment state of a mixed liquid crystal material, which is a mixture of smectic liquid crystal and chiral nematic material, with respect to the substrate.
If this interfacial alignment state cannot be controlled, even when used in liquid crystal light pulp, the initial transparent liquid crystal structure will not be obtained and image writing will not be possible, or even if it is possible, the display contrast will be extremely poor and it will not be practical. There wasn't. Although it has been confirmed in principle that it is effective to use a liquid crystal material that is a mixture of smectic liquid crystal and cholesteric liquid crystal in order to improve the image writing speed of liquid crystal light pulp, However, at present, a cholesteric liquid crystal that can be used practically has not been found and has not been realized. However, the present inventor has conducted experimental evaluations on a number of liquid crystal materials, and has found a liquid crystal material and constituent requirements for a liquid crystal light valve that can be put to practical use as a liquid crystal light pulp, and has thus arrived at the present invention.
（発明の目的）
本発明の目的は、書込み速度が速くてコントラストの高
い画像表示が可能な高信頼性の液晶ライトパルプを提供
することにある。(Object of the Invention) An object of the present invention is to provide a highly reliable liquid crystal light pulp that has a fast writing speed and is capable of displaying images with high contrast.
（発明の構成）
本発明の液晶ライトパルプは、電極を備えた２枚の相対
向する基板の間＠に液晶物質の薄層を挾持した構造の液
晶ライトパルプであシ、前記液晶コレステリック液晶と
を主成分とする液晶物質であシ、かつ該液晶物質の薄層
が１２μｍ以下の厚さである点に特徴がある。(Structure of the Invention) The liquid crystal light pulp of the present invention is a liquid crystal light pulp having a structure in which a thin layer of liquid crystal substance is sandwiched between two opposing substrates provided with electrodes, and the liquid crystal cholesteric liquid crystal and It is characterized in that it is a liquid crystal material whose main component is , and the thin layer of the liquid crystal material has a thickness of 12 μm or less.
（実施例） 以下に図面を参照して本発明の詳細な説明する。(Example) The present invention will be described in detail below with reference to the drawings.
第１図は本発明の液晶ライトパルプの一実施例の構造を
示す図である。第１図において、１は酸化インジウムの
透明電極２を備えたガラス基板、３はアルミ電極４を備
えたガラス基板で１）、ガラス基板３にはアルミ電極４
との間にカドミウムテルル膜５が設けられている。２枚
の基板１および３はその間隙に液晶物質の薄層６を挾持
して周囲をエポキシ接着剤７で固定封止されている。本
実施例で用いた液晶物質はスメクティック液晶ノルマル
オクチルシアノビフェニル、スメクティックされるコレ
ステリック液晶（以下Ｃ１５と記す）を重量比で７６．
８ ：１３．６ ： ９．６で混合した液晶物質であシ
、その薄層６の厚さは７５μｍである。なお、図では繁
雑となるので省略したが、２枚の基板およびその上の電
極の液晶物質と接する面には、酸化ケイ素の斜方蒸着に
よる、いわゆる平行配向処理が施されている。この構造
の液晶ライトパルプを用いて、基板３の側からアルゴン
レーザ光を照射して画像を書込み、この画像を基板１の
側からシュリーレン光学系を用いて白色光を照射して液
晶ライトパルプのアルミ面による反射像を拡大投映した
ところコントラスト１２：１の画像が１画素あたシ１．
２μｓと、コレステリック液晶を含有しない液晶物質を
用い九従来構造の液晶ライトパルプを用いた場合の１画
素あたシ１．５μｓの書込み速度と比べて高速の画像書
込みが行なえた。本実施例の液晶ライトパルプにおける
液晶物質の配向組織を偏光顕微鏡で観察したところ、第
２図（ｂ）に示すようにレーザ光を照射しない初期状態
において極めて均一な配向組織が得られていることが確
認された。比較のために、第１図と同じ構造で液晶物′
質の薄層の厚さだけが異なる液晶ライトパルプを数多く
作成して液晶物質の配向組織を観察したところ、液晶物
質の薄層の厚さが１２μｍ以下の場合には常に均一な配
向組織が得られた。逆に１２μｍを越えた場合には乱れ
た配向組織となシ、このよう々液晶ライトバルブを用、
いても、画像書込みは＃１とんど行なえなかった。液晶
物質の薄層の厚さを３．７μｍ、７．５μｍ、１１．２
μｍ ？ １５．０μｍｔ１８．７μｍ。FIG. 1 is a diagram showing the structure of an embodiment of the liquid crystal light pulp of the present invention. In Fig. 1, 1 is a glass substrate equipped with an indium oxide transparent electrode 2, 3 is a glass substrate equipped with an aluminum electrode 4 (1), and the glass substrate 3 is equipped with an aluminum electrode 4.
A cadmium telluride film 5 is provided between the two. The two substrates 1 and 3 are fixedly sealed around the periphery with an epoxy adhesive 7, with a thin layer 6 of liquid crystal material sandwiched between them. The liquid crystal material used in this example was smectic liquid crystal normal octyl cyanobiphenyl, and smectic cholesteric liquid crystal (hereinafter referred to as C15) at a weight ratio of 76.
8:13.6:9.6 is the liquid crystal material mixed, and the thickness of the thin layer 6 is 75 μm. Although not shown in the figure for the sake of complexity, the surfaces of the two substrates and the electrodes thereon that are in contact with the liquid crystal material are subjected to so-called parallel alignment treatment by oblique vapor deposition of silicon oxide. Using the liquid crystal light pulp with this structure, an image is written by irradiating argon laser light from the substrate 3 side, and this image is written on the liquid crystal light pulp by irradiating white light from the substrate 1 side using a schlieren optical system. When the reflected image from the aluminum surface was enlarged and projected, the image had a contrast of 12:1 and one pixel was 1.
Image writing can be performed at a high speed of 2 μs, compared to the writing speed of 1.5 μs per pixel when a liquid crystal light pulp having a conventional structure is used using a liquid crystal material that does not contain cholesteric liquid crystal. When the alignment structure of the liquid crystal material in the liquid crystal light pulp of this example was observed using a polarizing microscope, it was found that an extremely uniform alignment structure was obtained in the initial state without laser beam irradiation, as shown in FIG. 2(b). was confirmed. For comparison, we used a liquid crystal material with the same structure as in Figure 1.
When we created a number of liquid crystal light pulps that differed only in the thickness of the thin layer and observed the orientation structure of the liquid crystal material, we found that a uniform orientation structure was always obtained when the thickness of the thin layer of the liquid crystal material was 12 μm or less. It was done. On the other hand, if the thickness exceeds 12 μm, the alignment structure will be disordered.
Even though it was, image writing #1 could not be performed at all. The thickness of the thin layer of liquid crystal material is 3.7 μm, 7.5 μm, 11.2
μm? 15.0μmt18.7μm.
２Ｌ５μｍと変えたときの配向組織を観察した結果の例
をそれぞれ第２図（ａ）〜（ｆ）Ｋ示す。なお、液晶物
質の純度はすべての場合充分に高純度でｓｂ、常温での
抵抗率も１０１０Ω１台で絶縁破壊によるショート等の
問題も一切なく、充分な信頼性が確認される物質（以下
ＥＣＮ３と記す。）を用いた以外は第１図の実施例と同
じ構造の液晶ライトパルプを液晶物質の薄層の厚さを３
，７μｍ、７．５μｍ。Examples of the results of observing the oriented structure when the thickness was changed to 2L5 μm are shown in FIGS. 2(a) to 2(f)K, respectively. In all cases, the purity of the liquid crystal material is sufficiently high (sb), and the resistivity at room temperature is 1010 Ω per unit, without any problems such as short circuits due to dielectric breakdown, and the material has been confirmed to have sufficient reliability (hereinafter referred to as ECN3). A liquid crystal light pulp having the same structure as the example shown in Fig.
, 7 μm, 7.5 μm.
１１．３μｍ、、１５．１μｍ ｆ ｉ ＆９μｆｆ、
２２．７μｍと変えて作成し、液晶物質の配向状態を観
察したところ、第３図（＆）〜（ｆ）にそれぞれ例示す
るようにすべての液晶ライトパルプにおいて乱れた配向
組織しか得られず、いずれも画像書込みが行なえ々かっ
た。コレステリック液晶のＣ１５とＥＣＮ３はいずれも
カイラルネマティック材と称される物質、であるが、以
上述べたようにコレステリック液晶としてＣ１５を用い
、その薄層の厚さを１２μｍ以下□とした時にはじめて
均一な配向状態が得られることが見出さて表わされるコ
レステリック液晶を用いた場合等は、液晶相を呈する温
度範囲が狭くなる等の問題が生じて不都合でめった。11.3μm, 15.1μm f i &9μff,
When the liquid crystal light pulp was prepared with a different thickness of 22.7 μm and the orientation state of the liquid crystal material was observed, only a disordered orientation structure was obtained in all liquid crystal light pulps, as illustrated in FIGS. 3(&) to (f), respectively. In both cases, it was difficult to write images. The cholesteric liquid crystals C15 and ECN3 are both substances called chiral nematic materials, but as mentioned above, uniformity is achieved only when C15 is used as the cholesteric liquid crystal and the thickness of the thin layer is set to 12 μm or less. When cholesteric liquid crystals, which have been found to be able to obtain an oriented state, are used, problems such as a narrowing of the temperature range in which the liquid crystal phase is exhibited have resulted in inconvenience and failure.
一方、コレステリック液晶としてＣ１５を用いた場合に
はスメクティック液晶として、上述の実施例で用いた物
質以外にもビフェニル系やシック系の多くの物質を用い
ても同等の効果が得られた。On the other hand, when C15 was used as the cholesteric liquid crystal, similar effects were obtained even when many other substances such as biphenyl and chic types were used as the smectic liquid crystal in addition to the substances used in the above-mentioned examples.
なお、第１図の実施例で用いた材料は液晶物質以外は何
ら本発明を制限するものではなく、またカドミウムテル
ル膜はアル、ボンレーザ光の吸収効率を向上するために
設けたものであり、本発明による効果に対しては本質的
ではない。また、液晶物質に二色性色素を添加してレー
ザ光の吸収効率を改善する等の手法が本発明の液晶ライ
トパルプにおいても有効であることは言うまでもない。It should be noted that the materials used in the embodiment shown in FIG. 1 do not limit the present invention in any way other than the liquid crystal material, and the cadmium tellurium film was provided to improve the absorption efficiency of Al and Bone laser light. This is not essential to the effects of the present invention. It goes without saying that methods such as adding a dichroic dye to the liquid crystal material to improve the absorption efficiency of laser light are also effective in the liquid crystal light pulp of the present invention.
（発明の効果）
以上述べたように、本発明によれば書込み速度が速くて
コントラストの高い画像表示が可能な高信頼性の液晶ラ
イトパルプが得られる。(Effects of the Invention) As described above, according to the present invention, a highly reliable liquid crystal light pulp that has a fast writing speed and can display images with high contrast can be obtained.
第１図は本発明の液晶ライトパルプの一実施例の構造を
示す図であル、第１図において１はガラス基板、２は酸
化インジウムの電極、３はガラス基板、４はアルミの電
極、５はカドミウムテルル膜、６は液晶物質の薄層、７
はエポキシ接着剤である。第２図（ａ）〜（ｆ）および
第３図（ａ）〜（ｆ）は、液晶物質の配向組織を示す偏
光顕微鏡写真である。
代夏人弁理士内原
７１−１ 図FIG. 1 is a diagram showing the structure of an embodiment of the liquid crystal light pulp of the present invention. In FIG. 1, 1 is a glass substrate, 2 is an indium oxide electrode, 3 is a glass substrate, 4 is an aluminum electrode, 5 is a cadmium tellurium film, 6 is a thin layer of liquid crystal material, 7 is a thin layer of liquid crystal material;
is an epoxy adhesive. FIGS. 2(a) to 3(f) and 3(a) to 3(f) are polarized light micrographs showing the alignment structure of the liquid crystal material. Daikato Patent Attorney Uchihara 71-1 Figure
Claims (1)
薄層を挾持した構造の液晶ライトバルブにおいて、前記
液晶物質がスメクティック液晶と構造式▲数式、化学式
、表等があります▼で表わさ れるコレステリック液晶とを主成分とする液晶物質であ
り、かつ該液晶物質の薄層が１２μｍ以下の厚さである
ことを特徴とする熱書み液晶ライトバルブ。[Claims] In a liquid crystal light valve having a structure in which a thin layer of liquid crystal material is sandwiched between two opposing substrates each having an electrode, the liquid crystal material has a smectic liquid crystal and a structural formula ▲ mathematical formula, chemical formula, table A thermal writing liquid crystal light bulb is characterized in that it is a liquid crystal material whose main component is cholesteric liquid crystal represented by ▼, and the thin layer of the liquid crystal material has a thickness of 12 μm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13430784A JPS6113225A (en) | 1984-06-29 | 1984-06-29 | Liquid crystal light bulb |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13430784A JPS6113225A (en) | 1984-06-29 | 1984-06-29 | Liquid crystal light bulb |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6113225A true JPS6113225A (en) | 1986-01-21 |
Family
ID=15125229
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13430784A Pending JPS6113225A (en) | 1984-06-29 | 1984-06-29 | Liquid crystal light bulb |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6113225A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5895039A (en) * | 1981-11-30 | 1983-06-06 | Toshiba Corp | Paper feeder |
| JPS6052439A (en) * | 1983-08-31 | 1985-03-25 | Fuji Xerox Co Ltd | Automatic selecting apparatus for form-sheet size |
| US4792213A (en) * | 1985-08-12 | 1988-12-20 | The General Electric Company, P.L.C. | Thermal imaging device |
-
1984
- 1984-06-29 JP JP13430784A patent/JPS6113225A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5895039A (en) * | 1981-11-30 | 1983-06-06 | Toshiba Corp | Paper feeder |
| JPH0230974B2 (en) * | 1981-11-30 | 1990-07-10 | Tokyo Shibaura Electric Co | |
| JPS6052439A (en) * | 1983-08-31 | 1985-03-25 | Fuji Xerox Co Ltd | Automatic selecting apparatus for form-sheet size |
| US4792213A (en) * | 1985-08-12 | 1988-12-20 | The General Electric Company, P.L.C. | Thermal imaging device |
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