JPH08146417A - Light-diffusing sheet - Google Patents

Light-diffusing sheet

Info

Publication number
JPH08146417A
JPH08146417A JP6289685A JP28968594A JPH08146417A JP H08146417 A JPH08146417 A JP H08146417A JP 6289685 A JP6289685 A JP 6289685A JP 28968594 A JP28968594 A JP 28968594A JP H08146417 A JPH08146417 A JP H08146417A
Authority
JP
Japan
Prior art keywords
light
layer
dispersed
thermoplastic resin
sheet
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
Application number
JP6289685A
Other languages
Japanese (ja)
Inventor
Hirozo Nakamura
浩造 中村
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sekisui Chemical Co Ltd
Original Assignee
Sekisui Chemical Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sekisui Chemical Co Ltd filed Critical Sekisui Chemical Co Ltd
Priority to JP6289685A priority Critical patent/JPH08146417A/en
Publication of JPH08146417A publication Critical patent/JPH08146417A/en
Pending legal-status Critical Current

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  • Optical Elements Other Than Lenses (AREA)
  • Liquid Crystal (AREA)

Abstract

PURPOSE: To prevent appearance of dots and to enable efficient use of light by using anisotropic diffusion of light by forming a layer comprising a thermoplastic resin in which a fibrous material is dispersed parallel to each other and forming a layer in which a bead-type diffusing agent is dispersed. CONSTITUTION: The light-diffusing sheet consists of a layer comprising a thermoplastic resin in which a fibrous material is dispersed parallel to each other and a layer of a thermoplastic resin in which a bead-type diffusing agent is dispersed. From the layer A of the figure, light is emitted in such a manner that a wider visual angle is obtd. in the direction parallel to the fibrous material while a smaller visual angle is obtd. in the direction perpendicular to the fibrous material. In the layer B, light is uniformly diffused. These layers are combined in such a manner that the layer A is used as the upper layer to change the outgoing direction of light while the layer B having a high diffusing function is used as the lower layer to prevent appearance of dots. Thereby, much light can be given to the transverse direction of a liquid crystal screen while less light is given to the vertical direction, and light-emitting characteristics with high front-view luminance can be obtd.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は光拡散シートに関する。FIELD OF THE INVENTION The present invention relates to a light diffusion sheet.

【0002】[0002]

【従来の技術】パーソナルコンピュータや小型ワードプ
ロセッサ等の液晶表示装置を構成する液晶表示素子は、
自家発光性を有しないので、視認性向上の要求を満たす
ため、その背面光源として面状光源装置を用いている。
2. Description of the Related Art A liquid crystal display element that constitutes a liquid crystal display device such as a personal computer or a small word processor is
Since it does not have a self-luminous property, a planar light source device is used as its back light source in order to meet the demand for improved visibility.

【0003】面状光源装置は、開発当初には蛍光ランプ
等の光源を液晶表示素子の背面に直接配置した構造(直
下式)をとっていた。これに対し、近年では、液晶表示
装置全体の厚みを薄くして構造の小型化を図るため、面
状光源装置として導光板を用い、その少なくとも一端面
に蛍光ランプを配置したエッジライト方式という構造を
とることが多い。
At the beginning of development, the planar light source device had a structure (direct type) in which a light source such as a fluorescent lamp was arranged directly on the back surface of a liquid crystal display element. On the other hand, in recent years, in order to reduce the thickness of the entire liquid crystal display device and reduce the size of the structure, a light guide plate is used as a planar light source device, and a structure called an edge light system in which a fluorescent lamp is arranged on at least one end surface thereof is used. Is often taken.

【0004】図6はエッジライト方式の面状光源装置の
基本構造を示す模式図である。図6において、1は液晶
表示素子、2は面状光源装置である。面状光源装置2に
あっては、直線状光源としての蛍光ランプ3を導光板4
の側傍に設けている。導光板4の裏面にはドット印刷さ
れた塗料(光散乱性インキ)5が設けられ、導光板4の
背面には反射板6が配置され、導光板4の前面には光拡
散シート7が設けられている。
FIG. 6 is a schematic diagram showing the basic structure of an edge light type planar light source device. In FIG. 6, 1 is a liquid crystal display element and 2 is a planar light source device. In the planar light source device 2, the fluorescent lamp 3 as the linear light source is provided with the light guide plate 4.
It is provided by the side of. A dot-printed paint (light-scattering ink) 5 is provided on the back surface of the light guide plate 4, a reflection plate 6 is provided on the back surface of the light guide plate 4, and a light diffusion sheet 7 is provided on the front surface of the light guide plate 4. Has been.

【0005】蛍光ランプ3から発せられた光線は、導光
板4の端面から内部に侵入し、導光板4の裏面の塗料5
によって乱反射され、導光板4の表面から放出される。
塗料5は蛍光ランプ3から導光板4に入射した光を、導
光板4の表面のどの位置からも均等に放出させるための
光散乱性インキの印刷パターンであり、疑似光源とも言
えるものである。しかし、このままでは、液晶表示装置
として必要とされる輝度が十分でなく、また導光板4の
裏面の塗料5の印刷パターンが液晶表示素子1の正面か
ら視認されてしまう(ドット見え)。然るに、光拡散シ
ート7は、液晶表示装置の画面を観察する際に、液晶表
示素子1を通して背面の疑似光源、即ち上述の塗料5の
印刷パターンが視認されることなしに、均一発光できる
ように機能するものである。
A light beam emitted from the fluorescent lamp 3 enters inside from the end surface of the light guide plate 4, and paint 5 on the back surface of the light guide plate 4.
Is diffusely reflected by and is emitted from the surface of the light guide plate 4.
The paint 5 is a printed pattern of a light-scattering ink for causing the light entering the light guide plate 4 from the fluorescent lamp 3 to be uniformly emitted from any position on the surface of the light guide plate 4, and can also be called a pseudo light source. However, as it is, the brightness required for the liquid crystal display device is not sufficient, and the printed pattern of the paint 5 on the back surface of the light guide plate 4 is visually recognized from the front surface of the liquid crystal display element 1 (dots visible). Therefore, the light diffusion sheet 7 enables uniform light emission without observing the pseudo light source on the back surface, that is, the above-mentioned coating pattern of the paint 5 through the liquid crystal display element 1 when observing the screen of the liquid crystal display device. It works.

【0006】従来の光拡散シートは2つに大別され、1
つはプラスチックフィルム又はシートに白色顔料を塗布
したり混入させたものであり、他の1つはフィルムやシ
ートの表面に凹凸形状を付けたものである。
The conventional light diffusing sheet is roughly classified into two.
One is a plastic film or sheet coated with or mixed with a white pigment, and the other one is a film or sheet having an uneven surface.

【0007】前者の例としては、ポリエステル、ポリカ
ーボネート等の光透過性のあるフィルムもしくはシート
の片面又は両面に、酸化チタン等の白色顔料やガラス微
粉末等の光拡散材料を含む塗料を塗布したもの(特開昭
63-33703号公報)、及び上記樹脂中に上記光拡散材料を
充填した材料をフィルムもしくはシート状に成形したも
の(特開平1-209402号公報、特開平1-17280 号公報)が
挙げられる。
As an example of the former, one or both surfaces of a light-transmitting film or sheet such as polyester or polycarbonate coated with a paint containing a white pigment such as titanium oxide or a light diffusion material such as glass fine powder. (JP Sho
63-33703), and a material obtained by molding the above-mentioned light-diffusing material in the resin and molding it into a film or sheet (Japanese Patent Laid-Open Nos. 1-209402 and 1-17280).

【0008】後者の例としてはポリエステル、ポリカー
ボネート等の光透過性のある樹脂からなるフィルムもし
くはシートの片面又は両面に任意の凹凸加工を施したも
の(特開平1-13925 号公報)がある。
An example of the latter is a film or sheet made of a resin having a light-transmitting property such as polyester, polycarbonate or the like, which is provided with an arbitrary unevenness processing on one side or both sides (JP-A-1-13925).

【0009】近年では、前者で挙げた光拡散剤(充填
剤)は白色顔料でなくガラスビーズや繊維、又はアクリ
ルビーズなどにかわってきている。
In recent years, the light diffusing agent (filler) mentioned above has been replaced by glass beads, fibers, acrylic beads or the like instead of white pigments.

【0010】単に熱可塑性プラスチックス樹脂中にガラ
ス繊維を混入した従来技術には、特開昭52-11046号公報
に記載のものがあり、また、ガラス繊維の他に炭酸カル
シウムも混入した光拡散シートの従来技術には、特開昭
63-21704号公報に記載のもの、特開平1ー209402号公報に
記載のものがある。更に本発明に重要に関わる、異方的
形状物を樹脂中に平行、且つ分散配置し、拡散方向に異
方性を持たせる従来技術には、特開平4-314522号公報に
記載のものがある。
As a conventional technique in which glass fibers are simply mixed in a thermoplastic resin, there is one described in Japanese Patent Laid-Open No. 52-11046, and light diffusion in which calcium carbonate is mixed in addition to glass fibers. The conventional seat technology is disclosed in
There are those described in JP-A-63-21704 and those disclosed in JP-A-1-209402. Further importantly related to the present invention, the anisotropic shape is parallel to the resin, and dispersed, the prior art to give anisotropy in the diffusion direction, those described in JP-A-4-314522. is there.

【0011】[0011]

【発明が解決しようとする課題】然しながら、特開昭63
-21704号公報や、特開平1-209402号公報に記載の従来技
術では、ガラス繊維が平行でなく、分散配置しているた
め、ほぼ均一な光の分布となっている。
However, Japanese Patent Laid-Open No. Sho 63-63
In the prior arts described in Japanese Patent Publication No. -21704 and Japanese Patent Laid-Open No. 1-209402, the glass fibers are not parallel and are dispersed, so that the light distribution is almost uniform.

【0012】また、特開平4-314522号公報に記載の従来
技術では、繊維状物を平行、且つ分散配置しているた
め、繊維に平行な方向とそれに垂直な方向とで光の分布
に変化を持たせることが可能である。ところが、単にこ
のシートを用いただけでは十分な拡散が得られないため
に、光拡散シート本来のドット見え防止が不十分になっ
たり、繊維長が短いと、異方性拡散を起こさなくなって
しまう。
Further, in the prior art disclosed in Japanese Patent Laid-Open No. 4-314522, since the fibrous materials are arranged in parallel and dispersed, the distribution of light changes in the direction parallel to the fibers and the direction perpendicular thereto. It is possible to have However, since sufficient diffusion cannot be obtained simply by using this sheet, the original dot visibility prevention of the light diffusion sheet becomes insufficient, and if the fiber length is short, anisotropic diffusion does not occur.

【0013】然るに、液晶画面を見るときに、視野角を
広く取る必要のある方向(左右方向)には、視野角を広
げるために光を配し、視野角を広く取る必要のない方向
(上下方向)は、光を圧縮することが望ましい。なぜな
ら、全体として効率の良い光の利用が望めるからであ
る。そこで、拡散剤として繊維状物を平行、且つ分散配
置し、左右方向には光を多く、上下方向には光を少なく
するように光を配する。この様に効率の良い光の利用を
行なう必要があるのであるが、このままでは光の拡散が
不十分で、光拡散シート本来の役割であるドット見えを
防止できない。
However, when viewing the liquid crystal screen, light is arranged to widen the viewing angle in the direction where the viewing angle needs to be wide (horizontal direction). Direction) it is desirable to compress the light. This is because it is possible to expect efficient use of light as a whole. Therefore, fibrous materials are arranged in parallel and dispersed as a diffusing agent, and light is distributed so that light is increased in the left-right direction and light is decreased in the vertical direction. As described above, it is necessary to use light efficiently. However, if it is left as it is, the diffusion of light is insufficient and it is not possible to prevent the appearance of dots, which is the original role of the light diffusion sheet.

【0014】本発明は、光拡散シートにおいて、ドット
見えを防止するとともに、光の異方向性拡散を利用して
光の効率の良い利用を行なうことを目的とする。
It is an object of the present invention to prevent the appearance of dots in a light diffusing sheet and to utilize light in different directions to efficiently use light.

【0015】[0015]

【課題を解決するための手段】請求項1に記載の本発明
の光拡散シートは、熱可塑性プラスチックス樹脂中に繊
維状物を平行、且つ分散配置したA層と、熱可塑性プラ
スチックス樹脂中にビーズ形状の拡散剤を分散配置した
B層とで構成されるようにしたものである。
The light diffusing sheet of the present invention according to claim 1 is a thermoplastic resin containing an A layer in which fibrous materials are arranged in parallel and dispersed, and a thermoplastic resin. And a layer B in which a bead-shaped diffusing agent is dispersed and arranged.

【0016】[0016]

【作用】本発明の光拡散シートを構成するA層とB層は
以下の如くに機能する。 A層:熱可塑性プラスチックス樹脂中に繊維状物を平
行、且つ分散配置したもの。繊維状物に平行な方向には
視野角が広くなるように、光が出射され、繊維状物に垂
直な方向には視野角が狭くなるように光が出射される。
The layers A and B constituting the light diffusing sheet of the present invention function as follows. Layer A: A fibrous material arranged in parallel and dispersed in a thermoplastic resin. Light is emitted so that the viewing angle is wide in the direction parallel to the fibrous material, and light is emitted in the direction perpendicular to the fibrous material so that the viewing angle is narrow.

【0017】B層:熱可塑性プラスチックス樹脂中に拡
散剤(ビーズ)を分散配合し、均一な光の拡散を行なう
もの。
Layer B: A layer in which a diffusing agent (beads) is dispersed and mixed in a thermoplastic resin to diffuse light uniformly.

【0018】A層とB層を何枚か組み合わせて積層し、
1枚の光拡散シートにする(図2)。
A number of layers A and B are combined and laminated,
Use a single light diffusion sheet (Fig. 2).

【0019】基本構成は2層の組み合わせで、上の層に
A層を用いて光の出射方向に変化をつけ、下の層にはド
ット見えを防止するために、拡散機能の高いB層を用い
る。この組み合わせによって、ドット見えを防止すると
ともに光を効率良く利用した出射光特性が得られる。
The basic structure is a combination of two layers. A layer A is used as an upper layer to change the light emission direction, and a layer B having a high diffusion function is provided in the lower layer to prevent the appearance of dots. To use. With this combination, the appearance of dots can be prevented, and emission light characteristics that efficiently use light can be obtained.

【0020】他の組み合わせについても、基本的にA層
を一番上に載せるものとし、下の層でドット見え防止機
能の役目を果たすものとする。
For other combinations, the layer A is basically placed on the top, and the layer below serves as the dot visibility preventing function.

【0021】従って、本発明の拡散シートをエッジライ
ト方式の面状光源装置に使用した場合、ドット見えする
ことなく、液晶画面の左右方向に多くの光を配し、上下
方向に少なく光を配することを実現できる。そのため正
面輝度の高い出射光特性を得ることができる。
Therefore, when the diffusion sheet of the present invention is used in an edge light type planar light source device, a large amount of light is distributed in the left and right directions of the liquid crystal screen and a small amount of light is distributed in the up and down directions without seeing dots. Can be realized. Therefore, it is possible to obtain outgoing light characteristics with high front brightness.

【0022】更に表面に凹凸形状を持つプリズム型シー
トや、ウェーブ型シート等の下に本発明の光拡散シート
を用いると、従来の光拡散シートと凹凸形状を持つシー
トとを組み合わせたとき以上の正面輝度を得ることがで
きる。
Further, when the light diffusing sheet of the present invention is used under a prism type sheet having an uneven surface or a wave type sheet or the like, when the conventional light diffusing sheet and a sheet having an uneven shape are combined, The front brightness can be obtained.

【0023】[0023]

【実施例】液晶表示装置10を構成する液晶表示素子1
1の背面光源として、図5に示す如くの面状光源装置1
2を構成した。
EXAMPLES Liquid crystal display element 1 constituting liquid crystal display device 10
1 as a back light source, a planar light source device 1 as shown in FIG.
Configured 2.

【0024】面状光源装置12は、直線状光源としての
蛍光ランプ13を導光板14の側傍に設けている。導光
板14の裏面にはドット印刷された塗料(光散乱性イン
キ)15が設けられ、導光板14の背面には反射板16
が配置され、導光板14の前面には光拡散シート21が
設けられている。
The planar light source device 12 is provided with a fluorescent lamp 13 as a linear light source near the side of the light guide plate 14. A dot-printed paint (light-scattering ink) 15 is provided on the back surface of the light guide plate 14, and a reflection plate 16 is provided on the back surface of the light guide plate 14.
And a light diffusion sheet 21 is provided on the front surface of the light guide plate 14.

【0025】尚、光拡散シート21の前面に、更に表面
に凹凸形状を持つプリズム型シートや、ウェーブ型シー
トを配置するものであっても良い。
A prism type sheet or a wave type sheet having an uneven surface may be arranged on the front surface of the light diffusion sheet 21.

【0026】然るに、光拡散シート21として、ポリカ
ーボネート等の透明な熱可塑性樹脂中に径1 〜20μm 程
度、長さ50〜 100μm 程度のガラス繊維を互いに平行な
位置関係に分散配合したA層と、ポリカーボネート等の
透明な熱可塑性樹脂中に粒径2μm のアクリルビーズを
分散配合したB層を粘着ラミして積層し、1枚のシート
としたものを用い、以下の評価を行なった(表1)。
However, as the light diffusing sheet 21, a layer A in which glass fibers having a diameter of about 1 to 20 μm and a length of about 50 to 100 μm are dispersed and blended in a parallel positional relationship in a transparent thermoplastic resin such as polycarbonate, The following evaluations were carried out by using a layer B prepared by dispersing acrylic beads having a particle size of 2 μm dispersed and blended in a transparent thermoplastic resin such as polycarbonate as a single sheet to form a sheet (Table 1). .

【0027】同じ厚みのA層だけのもの、B層だけのも
の、A+B層のものを比較すると、A層だけのものは、
図3より異方性拡散の特性を示していることがわかる。
即ち繊維に平行な方向と垂直な方向とで出射光特性が違
うことを特徴としている。更に正面方向の透過率が非常
に高いことも特徴である。しかし、正面から見たときに
バックライトのドットが見えてしまう。
Comparing the A layer only, the B layer only, and the A + B layer having the same thickness, the A layer only
It can be seen from FIG. 3 that the characteristics of anisotropic diffusion are exhibited.
That is, it is characterized in that the emitted light characteristics are different in the direction parallel to the fiber and the direction perpendicular to the fiber. Another characteristic is that the transmittance in the front direction is very high. However, the dots of the backlight are visible when viewed from the front.

【0028】B層だけのものは、図4から均一な拡散
(完全拡散)の出射光特性を示していることがわかる。
均一な拡散を示すと、光を出射する必要のない方向にも
光を出射してしまうため、光の有効利用(効率)を考え
ると大きなロスをしていることになる。しかし、B層だ
けのものは、拡散能力が高い(図4より広い範囲で光強
度が高い)ので他のシートに比べバックライトのドット
が見え難いのが特徴である。
It can be seen from FIG. 4 that only the B layer exhibits uniform diffused (completely diffused) outgoing light characteristics.
If the uniform diffusion is shown, the light is emitted also in the direction in which it is not necessary to emit the light, so that a significant loss occurs when the effective use (efficiency) of the light is considered. However, the layer B alone has a high diffusing ability (higher light intensity in a wider range than FIG. 4), so that the dots of the backlight are less visible than other sheets.

【0029】一方A+B層を組み合わせたシート(A層
を上、B層を下として使用)は両方の良いところを取り
入れるものとなる。B層のドット見え防止効果と、A層
の異方性拡散の出射光特性である。このため液晶表示画
面を見るとき、A層によって左右方向には広い範囲で明
るく、それだけ視野角が広くとれ、上下方向には余り拡
散しないので視野角を狭くする。このため光を有効に使
い、且つ液晶画面を見たときにB層によってドット見え
がしないものとなる。A層のみ、B層のみ、A+B層の
性能評価を表1に示す。
On the other hand, a sheet in which layers A + B are combined (A layer is used as the upper side and B layer is used as the lower side) incorporates both advantages. These are the dot visibility prevention effect of the B layer and the emission light characteristics of the anisotropic diffusion of the A layer. Therefore, when viewing the liquid crystal display screen, the layer A is bright in a wide range in the left-right direction, the viewing angle can be widened accordingly, and the viewing angle is narrowed because it does not diffuse much in the vertical direction. For this reason, the light is effectively used, and when the liquid crystal screen is viewed, the dots are not visible due to the layer B. Table 1 shows the performance evaluation of the A layer only, the B layer only, and the A + B layer.

【表1】 [Table 1]

【0030】尚、本発明の実施において、A層の熱可塑
性プラステック樹脂中に平行配置される繊維状物は、互
いに交わらなければ平面視で交差しているかに見えるも
のであっても良いが、互いに同一方向を指して並置され
るとき、本発明の効果は更に良い。
In the practice of the present invention, the fibrous materials arranged in parallel in the thermoplastic resin of layer A may appear as if they intersect in plan view if they do not intersect with each other. The effects of the present invention are even better when they are juxtaposed in the same direction.

【0031】[0031]

【発明の効果】以上のように本発明によれば、光拡散シ
ートにおいて、ドット見えを防止するとともに、光の異
方向性拡散を利用して光の効率の良い利用を行なうこと
ができる。
As described above, according to the present invention, it is possible to prevent the appearance of dots in the light diffusing sheet and to use the light in different directions to efficiently use the light.

【図面の簡単な説明】[Brief description of drawings]

【図1】図1は本発明の一実施例に係る液晶表示装置を
示す模式図である。
FIG. 1 is a schematic view showing a liquid crystal display device according to an embodiment of the present invention.

【図2】図2は光拡散シートの構成を示す模式図であ
る。
FIG. 2 is a schematic diagram showing a configuration of a light diffusion sheet.

【図3】図3はA層の出射光特性を示す線図である。FIG. 3 is a diagram showing emission light characteristics of an A layer.

【図4】図4はB層の出射光特性を示す線図である。FIG. 4 is a diagram showing emission light characteristics of a B layer.

【図5】図5はA+B層の出射光特性を示す線図であ
る。
FIG. 5 is a diagram showing emission light characteristics of A + B layers.

【図6】図6は従来例を示す模式図である。FIG. 6 is a schematic view showing a conventional example.

【符号の説明】[Explanation of symbols]

10 液晶表示装置 11 液晶表示素子 12 面状光源装置 13 蛍光ランプ(光源) 14 導光板 21 光拡散シート 10 liquid crystal display device 11 liquid crystal display element 12 planar light source device 13 fluorescent lamp (light source) 14 light guide plate 21 light diffusion sheet

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 熱可塑性プラスチックス樹脂中に繊維状
物を平行、且つ分散配置したA層と、熱可塑性プラスチ
ックス樹脂中にビーズ形状の拡散剤を分散配置したB層
とで構成される光拡散シート。
1. A light comprising a layer A in which fibrous materials are arranged in parallel and dispersed in a thermoplastic resin, and a layer B in which a bead-shaped diffusing agent is dispersed in the thermoplastic resin. Diffusion sheet.
JP6289685A 1994-11-24 1994-11-24 Light-diffusing sheet Pending JPH08146417A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6289685A JPH08146417A (en) 1994-11-24 1994-11-24 Light-diffusing sheet

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6289685A JPH08146417A (en) 1994-11-24 1994-11-24 Light-diffusing sheet

Publications (1)

Publication Number Publication Date
JPH08146417A true JPH08146417A (en) 1996-06-07

Family

ID=17746425

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6289685A Pending JPH08146417A (en) 1994-11-24 1994-11-24 Light-diffusing sheet

Country Status (1)

Country Link
JP (1) JPH08146417A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1156359A1 (en) * 1999-11-24 2001-11-21 Citizen Watch Co. Ltd. Liquid crystal display unit
WO2002033450A1 (en) 2000-10-19 2002-04-25 Daicel Chemical Industries, Ltd. Anisotropic scattering sheet and its use
JP2002214409A (en) * 2001-01-16 2002-07-31 Toppan Printing Co Ltd Light diffusing body and liquid crystal display device
JP2003004912A (en) * 2001-06-20 2003-01-08 Keiwa Inc Optical sheet and backlight unit using the same
US6606133B1 (en) 1999-02-04 2003-08-12 Keiwa Inc. Light diffusing sheet with direction-dependent diffusing ability
JP2004086145A (en) * 2002-06-24 2004-03-18 Seiko Epson Corp Display device and electronic apparatus provided with same
DE10129967B4 (en) * 2000-06-22 2012-02-02 Daicel Chemical Industries, Ltd. laminate film

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6606133B1 (en) 1999-02-04 2003-08-12 Keiwa Inc. Light diffusing sheet with direction-dependent diffusing ability
EP1156359A1 (en) * 1999-11-24 2001-11-21 Citizen Watch Co. Ltd. Liquid crystal display unit
EP1156359A4 (en) * 1999-11-24 2004-03-31 Citizen Watch Co Ltd Liquid crystal display unit
US6933994B1 (en) 1999-11-24 2005-08-23 Citizen Watch Co., Ltd. Liquid crystal display including an anisotropic scattering layer
DE10129967B4 (en) * 2000-06-22 2012-02-02 Daicel Chemical Industries, Ltd. laminate film
WO2002033450A1 (en) 2000-10-19 2002-04-25 Daicel Chemical Industries, Ltd. Anisotropic scattering sheet and its use
US6909480B2 (en) 2000-10-19 2005-06-21 Daicel Chemical Industries, Ltd. Anisotropic scattering sheet and its use
JP2002214409A (en) * 2001-01-16 2002-07-31 Toppan Printing Co Ltd Light diffusing body and liquid crystal display device
JP2003004912A (en) * 2001-06-20 2003-01-08 Keiwa Inc Optical sheet and backlight unit using the same
JP2004086145A (en) * 2002-06-24 2004-03-18 Seiko Epson Corp Display device and electronic apparatus provided with same

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