JPH05127159A - Back light - Google Patents
Back lightInfo
- Publication number
- JPH05127159A JPH05127159A JP3275022A JP27502291A JPH05127159A JP H05127159 A JPH05127159 A JP H05127159A JP 3275022 A JP3275022 A JP 3275022A JP 27502291 A JP27502291 A JP 27502291A JP H05127159 A JPH05127159 A JP H05127159A
- Authority
- JP
- Japan
- Prior art keywords
- light
- backlight
- guide plate
- sheet
- light guide
- 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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、透過型又は、半透過型
パネルを背面より照射するパネル用バックライトに関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight for a panel which illuminates a transmissive or semi-transmissive panel from the back side.
【０００２】[0002]
【従来の技術】近時、ラップトップ型又は、ブック型の
ワ−ドプロセッサ−やコンピュ−タ等の表示装置とし
て、薄型でしかも見易いバックライト機構を有する液晶
表示装置が用いられている。このようなバックライトに
は、図１に示すように透光性の導光板の一端部に、蛍光
管のような線状光源を併設する１灯型エッジライト方
式、図３に示すように透光性の導光板の対向する二端部
に、蛍光管のような線状光源を併設する２灯型エッジラ
イト方式、がよく用いられる。このエッジライト方式の
場合、図２又図４はに示すように、導光板の一方の面に
この導光板材料よりも屈折率が大きい光拡散物質を部分
的に被覆し、その面のほぼ全面を光拡散反射板で覆うよ
うに配置されたものが多い。2. Description of the Related Art Recently, a liquid crystal display device having a thin and easy-to-read backlight mechanism has been used as a display device for a laptop or book type word processor, a computer or the like. For such a backlight, a one-lamp type edge light system in which a linear light source such as a fluorescent tube is provided at one end of a light-transmitting light guide plate as shown in FIG. 1, and as shown in FIG. A two-lamp type edge light system in which a linear light source such as a fluorescent tube is provided at two opposite ends of a light guide plate is often used. In the case of this edge light system, as shown in FIG. 2 or 4, one surface of the light guide plate is partially covered with a light diffusing substance having a refractive index larger than that of the material of the light guide plate, and almost the entire surface thereof is covered. Many are arranged so as to be covered with a light diffusion reflector.
【０００３】特に近時、バックライトがバッテリー駆動
されるようになり消費電力−輝度変換効率のより一層の
向上が望まれており、線状光源を覆う光反射器に反射率
の高い反射板を配したり、導光板の光拡散物質を部分的
に被覆した面に反射率の高い反射板を配したりすること
が提案されている。Particularly, in recent years, since the backlight is driven by a battery, further improvement of power consumption-luminance conversion efficiency is desired, and a light reflector for covering the linear light source is provided with a reflector having a high reflectance. It has been proposed to dispose the light guide plate or to dispose a reflection plate having a high reflectance on the surface of the light guide plate that is partially covered with the light diffusing substance.
【０００４】しかし、前記したいづれの方法において
も、消費電力−輝度変換効率は向上するものの、未だ充
分でなく、更により一層の向上が望まれている。However, although the power consumption-luminance conversion efficiency is improved by any of the above-mentioned methods, it is still not sufficient, and further improvement is desired.
【０００５】[0005]
【発明が解決しようとする課題】本発明の目的は、消費
電力−輝度変換効率が高く、かつ高輝度が得られるバッ
クライトを提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a backlight which has high power consumption-luminance conversion efficiency and high luminance.
【０００６】[0006]
【課題を解決するための手段】本発明者等は、上述の点
につき種々の検討を行った結果、光拡散物質を部分的に
被覆した透光性材料の出光面側に、直線状頂稜を多数有
する透光性プリズムシ−トを配したが、光の指向性がよ
り強くなり、実質的に出光面に降ろした法線方向近傍に
対しては前記した消費電力−輝度変換効率の高いバック
ライトとなることを見出した。As a result of various investigations on the above points, the inventors of the present invention have found that a linear top edge is formed on the light emitting surface side of a translucent material partially covered with a light diffusing substance. Although a light-transmitting prism sheet having a large number of is arranged, the directivity of light becomes stronger, and the power consumption-brightness conversion efficiency described above is substantially high in the vicinity of the normal direction dropped to the light exit surface. I found it to be a light.
【０００７】即ち本発明は、透光性材料からなる導光板
の一方の広い面に、該導光板材料よりも屈折率が大きい
光拡散物質を部分的に被覆し、その面を鏡面ないし光反
射板で覆い、前記導光板の少なくとも一側面端部にこれ
に近接した線状光源を有するパネル用バックライトに於
いて、導光板の出光面側に、同一面に微細な間隔で直線
状頂稜を持つプリズムが、頂稜がほぼ平行となる状態で
多数有する透光性材料からなるシ−トを、頂稜面が外側
になるように、出光面側に１枚以上配置したパネル用バ
ックライト次に本発明を図面に基づいて詳述する。図５
は、導光板の一端部に光源を持つエッジライト方式の一
実施態様の斜視図であり、図６はその断面図である。同
様に図７は、導光板の二端部に光源を持つエッジライト
方式の一実施態様の斜視図であり、図８はその断面図で
ある。That is, according to the present invention, one wide surface of a light guide plate made of a translucent material is partially covered with a light diffusing substance having a refractive index higher than that of the light guide plate material, and the surface is mirror-finished or light-reflecting. In a backlight for a panel, which is covered with a plate and has a linear light source near at least one side surface end of the light guide plate, a straight top edge is formed on the same surface of the light guide plate at a minute interval on the light emitting surface side. A back light for a panel in which one or more sheets of translucent material having a plurality of prisms each having an apex that are substantially parallel to each other are arranged on the light emitting surface side so that the apex surface is on the outside. Next, the present invention will be described in detail with reference to the drawings. Figure 5
FIG. 6 is a perspective view of an embodiment of an edge light system having a light source at one end of a light guide plate, and FIG. 6 is a sectional view thereof. Similarly, FIG. 7 is a perspective view of an embodiment of an edge light system having light sources at two ends of the light guide plate, and FIG. 8 is a sectional view thereof.
【０００８】図中１は導光板であり、光を効率よく通過
させる物質であればよく、石英、ガラス、透光性の天然
又は合成樹脂、例えばアクリル系樹脂等である。導光板
に施す光拡散物質（図中６）は、導光板の材質に比較し
て高屈折率を持ち、かつ拡散反射率が大きい顔料、例え
ばチタンホワイトを含んだ塗料、印刷インキ等である。
これらをスクリ−ン印刷等の方法で導光板面上にドット
状に印刷する。In the figure, reference numeral 1 denotes a light guide plate, which may be any substance that allows light to pass efficiently, and is made of quartz, glass, translucent natural or synthetic resin such as acrylic resin. The light diffusing substance (6 in the figure) applied to the light guide plate is a pigment having a high refractive index and a large diffuse reflectance as compared with the material of the light guide plate, for example, paint containing titanium white, printing ink or the like.
These are printed in dots on the surface of the light guide plate by a method such as screen printing.
【０００９】４は線状光源で、好ましい態様としては、
導光板の端部に光が入光するための間隙（スリット）を
有する光反射器５で、線状光源の光源面とある幅の間隙
をもたせた状態で覆われており、導光板の少なくとも一
端面部に近接してその中心軸が導光板の端面とほぼ平行
となるように設置される。前記線状光源は、蛍光管、タ
ングステン白熱管、オプティカルロッド、ＬＥＤを配列
した物等があるが、蛍光管が好ましく、省電力の面か
ら、電極部を除く均一発光部の長さが、近接する導光板
の端部の長さとほぼ等しいことが好ましい。Reference numeral 4 is a linear light source, and in a preferred embodiment,
A light reflector 5 having a gap (slit) for allowing light to enter the end of the light guide plate is covered with a gap of a certain width from the light source surface of the linear light source, and at least the light guide plate is covered. It is installed close to the one end face so that its central axis is substantially parallel to the end face of the light guide plate. Examples of the linear light source include a fluorescent tube, a tungsten incandescent tube, an optical rod, an LED array, and the like. However, a fluorescent tube is preferable, and from the viewpoint of power saving, the length of the uniform light emitting portion excluding the electrode portion is close to each other. It is preferable that the length of the end portion of the light guide plate is substantially equal.
【００１０】鏡面ないし光拡散反射板（図中３）は光拡
散物質を被覆した導光板の面のほぼ全面を覆うように配
置するが、導光板の線状光源を近接させていない残りの
端面部のほぼ全面を覆うように配置すると光の利用効率
及び均一な面状発光を得る点で更に良い。The mirror surface or the light diffusing / reflecting plate (3 in the figure) is arranged so as to cover almost the entire surface of the light guiding plate coated with the light diffusing substance, but the remaining end surface of the light guiding plate which is not in close proximity to the linear light source. It is more preferable to dispose so as to cover almost the entire surface of the portion in terms of light utilization efficiency and uniform planar light emission.
【００１１】２は透光性材料からなるシ−ト（以下単に
シートと称する）で、同一面に微細な間隔で互いに平行
な直線状頂稜を多数有するもので、頂稜面が外側（導光
板と相対する面と反対側）になるように配置することに
より、バックライトの出光面より出光した光の指向性を
変化させ、出光面に降ろした法線方向近傍に対する指向
性をより強くさせるものである。前記直線状頂稜部が線
状光源の中心軸と平行になるように配置しても良いし、
直角になるように配置しても良い。A sheet 2 made of a translucent material (hereinafter simply referred to as a sheet) 2 has a large number of straight apexes parallel to each other on the same surface at fine intervals. By arranging it so that it is on the side opposite to the surface facing the light plate), the directivity of the light emitted from the light emitting surface of the backlight is changed, and the directivity in the vicinity of the normal direction dropped on the light emitting surface is made stronger. It is a thing. It may be arranged such that the linear apex portion is parallel to the central axis of the linear light source,
You may arrange so that it may become a right angle.
【００１２】本発明ではこのシ−トを１枚又は複数枚用
いるが、例えば２枚用いる場合には、互いの直線状頂稜
部が直交するように２枚とも頂稜面が外側になるように
重ね合わせれば、本発明の効果は更に増加する。尚、導
光板面上に印刷されたドット状の光拡散物質（図中６）
のドット状のパタ−ンの識別が不可能となるように、必
要に応じて、前記シ−トと前記導光板との間に光拡散板
（図中２）を配置しても良い。In the present invention, one sheet or a plurality of sheets are used. When, for example, two sheets are used, both apical ridges are located outside so that their linear apical ridges are orthogonal to each other. The effect of the present invention is further increased by superimposing the above. In addition, dot-shaped light diffusion material printed on the surface of the light guide plate (6 in the figure)
If necessary, a light diffusing plate (2 in the figure) may be arranged between the sheet and the light guide plate so that the dot-shaped pattern of FIG.
【００１３】本発明は、前記したように、バックライト
の出光面側に、ある条件を満足する形状を持つ透光性材
料からなるシ−トを配置することが特徴である。As described above, the present invention is characterized in that a sheet made of a translucent material having a shape satisfying a certain condition is arranged on the light emitting surface side of the backlight.
【００１４】本発明における前記条件を更に詳述する
と、前記したシ−ト（図中７）は透光性材料からなるも
のであれば特に限定されないが、例えばメタクリル酸エ
ステル、ポリカ−ボネイト、ポリ塩化ビニル、ポリスチ
レン、ポリアミド、ポリエステル、ポリエチレン、ポリ
プロピレン、繊維素系樹脂ガラス等である。The conditions in the present invention will be described in more detail. The sheet (7 in the figure) is not particularly limited as long as it is made of a translucent material. For example, methacrylic acid ester, polycarbonate, and polycarbonate. Examples thereof include vinyl chloride, polystyrene, polyamide, polyester, polyethylene, polypropylene, and fiber-based resin glass.
【００１５】本発明で用いるシ−トの、出光面側に形成
する互いに平行な直線状頂稜を有するプリズムの形状は
図９に示したように、光学的平面を２つ以上持ついわゆ
るプリズム状のもので、前記２つの光学的平面が交わる
頂稜（図中８）は直線状で、同一面内には微細な間隔
（図中Ｐ）で互いに平行な多数の直線状プリズムが存在
する状態である。シートに形成するこれら頂稜の頂角は
実質的に同じ形状の部分を持つもので、このことは、頂
点を中心として同一の条件で裁断した際にその頂角が実
質的に同じ角度を持つことを意味する。As shown in FIG. 9, the sheet used in the present invention has prisms having straight apexes that are parallel to each other and are formed on the light output surface side. As shown in FIG. 9, the prism has two or more optical planes. The apex edge (8 in the figure) where the two optical planes intersect is linear, and a large number of linear prisms parallel to each other are present in the same plane at minute intervals (P in the figure). Is. The apex angles of these apexes formed on the sheet have portions of substantially the same shape, which means that the apex angles have substantially the same angle when cut under the same conditions centering on the apex. Means that.
【００１６】本発明に於いては、前記したシ−トの頂稜
の頂角（図中９）は７０〜１５０度であることが好まし
い。前記頂角のより好ましい角度範囲は用いるシ−トの
材料の屈折率および用いる面状発光体の配光特性に依存
する。例えば屈折率の大なる材料（ポリカ−ボネート、
屈折率ｎ＝１．５９）を用いた場合は、頂角は７０度よ
りも９０度、９０度よりも１２０度のほうが好ましく１
５０度以上になると本発明の効果は減少し、配光特性、
例えば面状発光体から出光する光が出光面に降ろした法
線方向から４５度以内に実質的に集中している場合は、
頂角は１００度〜１４０度が良い。In the present invention, it is preferable that the apex angle (9 in the figure) of the apex of the sheet is 70 to 150 degrees. The more preferable range of the apex angle depends on the refractive index of the sheet material used and the light distribution characteristics of the planar light emitter used. For example, a material with a large refractive index (polycarbonate,
When the refractive index n = 1.59) is used, the apex angle is preferably 90 degrees rather than 70 degrees and 120 degrees rather than 90 degrees.
When the temperature exceeds 50 degrees, the effect of the present invention decreases, and the light distribution characteristics,
For example, when the light emitted from the planar light-emitting body is substantially concentrated within 45 degrees from the normal direction dropped on the light-emitting surface,
The vertical angle is preferably 100 to 140 degrees.
【００１７】又、前記したシ−トのプリズムの、頂点か
らのそれぞれの斜辺の長さが実質的に等しいものを用い
ることが、本発明の効果を向上させる上で特に好まし
い。又、シートに形成した多数の直線状プリズムの分布
状態は、表面から出光される光によって直線状プリズム
の間隔が視認されにくくする上で、互いに平行で隣り合
った直線状プリズムの頂稜と頂稜の間隔は１０〜１００
０μｍであることが好ましい。そして前記シ−トの直線
状プリズム部の厚さ（図中ｔ２）は前記した頂稜の頂角
及び頂稜と頂稜の間隔で決まるが、多数の直線状プリズ
ムを微細な間隔で互いに平行な位置関係に維持するため
の厚さ（図中ｔ１）が必要で、このｔ１は光線透過率及
びバックライトの薄型化のためには薄い方が良いが、前
記シ−トの製造上の理由及び強度の点から、前記シ−ト
の総厚（図中Ｔ）は１０〜３０００μｍ、好ましくは５
０〜１０００μｍが良い。また、同一面に形成する直線
状プリズムは、より効果的には同一形状のものが良い。Further, it is particularly preferable to use the above-mentioned sheet prism in which the lengths of the respective hypotenuses from the apex are substantially equal in order to improve the effect of the present invention. In addition, the distribution state of a large number of linear prisms formed on the sheet makes it difficult for the light emitted from the surface to visually recognize the interval between the linear prisms. The ridge spacing is 10-100
It is preferably 0 μm. The thickness (t2 in the figure) of the linear prism portion of the sheet is determined by the apex angle of the apex ridge and the interval between the apex ridges described above. It is necessary to have a thickness (t1 in the figure) to maintain such a positional relationship, and this t1 is preferably thin in order to reduce the light transmittance and the thickness of the backlight. From the viewpoint of strength, the total thickness (T in the figure) of the sheet is 10 to 3000 μm, preferably 5
0 to 1000 μm is preferable. Further, the linear prisms formed on the same surface should have the same shape more effectively.
【００１８】本発明で用いるシートを成形する方法は特
に限定されるものではなく、例えば熱プレスによる金型
成型加工、エンボス加工、鋳型加工、化学処理等の方法
で実質的に同形の直線状プリズムを微細な間隔で互いに
平行な状態で多数有するように成形可能な方法であれば
良い。尚、製造上の理由から頂稜には若干のだれが生じ
るが、本発明の効果が認められる範囲であれば良い。The method of molding the sheet used in the present invention is not particularly limited, and for example, a linear prism of substantially the same shape can be formed by a method such as die molding by hot pressing, embossing, casting, or chemical treatment. Any method can be used as long as it can be molded so as to have a large number of fine particles in parallel with each other. It should be noted that although a slight sag occurs at the apex for manufacturing reasons, it may be within the range in which the effects of the present invention are recognized.
【００１９】液晶ディスプレイは、その表示面に降ろし
た法線方向から視認する角度が大きくなる程コントラス
トが低くなるため、実用上、前記法線方向近傍での輝度
が重視される。更に、ビュ−ファインダ−に至ってはそ
の表示面に降ろした法線方向からしか見ないため、実用
上、前記法線方向近傍での輝度が重視される。In a liquid crystal display, the contrast becomes lower as the viewing angle from the direction of the normal drawn to the display surface becomes larger. Therefore, practically, the brightness in the vicinity of the direction of the normal is important. Further, since the viewfinder can be seen only from the normal direction dropped on the display surface, practically, the brightness in the vicinity of the normal direction is important.
【００２０】本発明で、前記したように、出光面側が微
細な間隔で互いに平行な多数の直線状プリズムを有する
シ−トを、前記バックライトの出光面に配すると、光の
指向性が現われる。即ち、実質的に出光面に降ろした法
線方向でその面より出光した光の輝度を測定した場合、
前記シ−トを配さない場合に比較して、輝度が増加され
ること、前記出光面に降ろした法線に対してある角度、
例えば４０度の方向から同様に測定した輝度が、実質的
に法線方向で測定した時の輝度よりその減少割合が大と
なる（例えば、法線方向で測定した時の輝度のほぼ５０
％まで減少する）こと等から、前記した光の指向性が現
れていることが判る。In the present invention, as described above, when a sheet having a large number of linear prisms whose light emitting surface side is parallel to each other at fine intervals is arranged on the light emitting surface of the backlight, the directivity of light appears. .. That is, when the brightness of the light emitted from the surface is measured in the direction of the normal line lowered to the light emitting surface,
Compared to the case where the sheet is not provided, the brightness is increased, an angle with respect to the normal line lowered to the light exit surface,
For example, the luminance measured similarly from the direction of 40 degrees has a larger reduction rate than the luminance measured in the normal direction (for example, almost 50% of the luminance measured in the normal direction).
It is understood that the above-mentioned light directivity appears.
【００２１】次に、本発明における作用を図面に基づい
て更に詳述する。図１０は本発明で、直線状プリズムを
有するシートを用いた場合の、シ−トの任意のプリズム
の断面に任意の点から入射する光線を光線追跡した一例
の図である。Next, the operation of the present invention will be described in more detail with reference to the drawings. FIG. 10 is a diagram showing an example of ray tracing of a ray incident from an arbitrary point on the cross section of an arbitrary prism of the sheet in the case of using a sheet having a linear prism in the present invention.
【００２２】プリズムの頂角を２α（度）とし、透光性
材料からなるシ−トの屈折率をｎ、空気の屈折率を１と
すると、臨界角θｃ（度）は θｃ＝ｓｉｎ−１（１／ｎ） １）光線が角度θ１（度）で入射し、角度θ６（度）で
出射する場合（図１０） ｓｉｎθ１＝ｎ×ｓｉｎθ２ θ３＝９０°−α−θ２ ｎ×ｓｉｎθ３＝ｓｉｎθ４ （ただしθ３≦θｃのと
き） θ５＝９０°−α−θ４ θ６＝θ５ ２）光線が角度θ１（度）で入射し、角度θ８（度）で
出射する場合（図１１） ｓｉｎθ１＝ｎ×ｓｉｎθ２ θ３＝９０°−α−θ２ θ４＝θ３ （ただしθ３＞θｃのとき） θ５＝２α−θ４ ｎ×ｓｉｎθ５＝ｓｉｎθ６ （ただしθ５≦θｃのと
き） θ７＝９０°−α−θ６ θ８＝−θ７ このような計算を行うことによって、透光性材料からな
るシ−トに用いる材料の屈折率、プリズムの頂角がわか
れば、バックライトの出光面から出光する光線の透光性
材料からなるシ−トへの入射角から出射角を求めること
が出来る。尚、図１０には示さなかったが、前記条件に
よっては、入射光線はプリズム内部を２回以上反射する
場合もあるし、バックライトの出光面に戻る場合もあ
る。When the apex angle of the prism is 2α (degrees), the refractive index of the sheet made of a translucent material is n, and the refractive index of air is 1, the critical angle θc (degrees) is θc = sin −1. (1 / n) 1) beam is incident at an angle theta 1 (degrees), when emitted at the angle theta 6 (degrees) (Fig. 10) sinθ 1 = n × sinθ 2 θ 3 = 90 ° -α-θ 2 n × sin θ 3 = sin θ 4 (where θ 3 ≦ θc) θ 5 = 90 ° −α−θ 4 θ 6 = θ 5 2) A light beam is incident at an angle θ 1 (degrees) and an angle θ 8 (degrees). ) (FIG. 11) sin θ 1 = n × sin θ 2 θ 3 = 90 ° −α−θ 2 θ 4 = θ 3 (when θ 3 > θc) θ 5 = 2α−θ 4 n × sin θ 5 = sin [theta by 6 (provided that when θ 5 ≦ θc) by performing θ 7 = 90 ° -α-θ 6 θ 8 = -θ 7 such calculations, translucent If the refractive index of the material used for the sheet made of material and the apex angle of the prism are known, the exit angle can be obtained from the incident angle of the light beam emitted from the light emitting surface of the backlight to the sheet made of the translucent material. Can be done. Although not shown in FIG. 10, depending on the above conditions, the incident light beam may be reflected twice or more inside the prism or may return to the light emitting surface of the backlight.
【００２３】例えば、図１２に示したように前記シ−ト
をポリカ−ボネート（屈折率ｎ＝１．５９）で作り、プ
リズムの頂角を９０度にした場合に於いては、入射角０
度で前記シ−トに入射した光線はプリズム内部で全反射
し、バックライトへ戻される。バックライトへ戻された
光線はバックライト内部で一部は吸収され、一部は反射
し再びバックライトの出光面より出光する。For example, as shown in FIG. 12, when the sheet is made of polycarbonate (refractive index n = 1.59) and the apex angle of the prism is 90 degrees, the incident angle is 0.
The light beam incident on the sheet at a time is totally reflected inside the prism and returned to the backlight. The light rays returned to the backlight are partially absorbed inside the backlight, partially reflected, and emitted again from the light emitting surface of the backlight.
【００２４】従って、この様にバックライトから出光し
た光が前記シ−トのプリズム内部で全反射して再びバッ
クライトへ戻される場合には、バックライト内部での光
の吸収が少ない程、またバックライト内部での光の反射
率が高い程すなわちバックライトの出光面以外の面が反
射率の高い反射板で覆われている程、効率の良いバック
ライトになる。Therefore, when the light emitted from the backlight is totally reflected inside the prism of the sheet and returned to the backlight again, the less light is absorbed inside the backlight, The higher the reflectance of light inside the backlight, that is, the surface of the backlight other than the light emitting surface is covered with a reflector having a high reflectance, the more efficient the backlight becomes.
【００２５】また、入射角３０度で前記シ−トに入射し
た光線は出射角０．５度で前記シ−トより出光し、入射
角６０度で前記シ−トに入射した光線は出射角２５．７
度で前記シ−トより出光する。そして、この場合のバッ
クライトの出光面から出光する光は実質的に前記出光面
に降ろした法線方向からの角度がほぼ４０度以内に最も
集中し、その結果、前記法線方向から測定した輝度が、
前記シ−トを配さない場合に比較して増加する。A light ray incident on the sheet at an incident angle of 30 degrees is emitted from the sheet at an emission angle of 0.5 degree, and a light ray incident on the sheet at an incident angle of 60 degrees is emitted at an emission angle. 25.7
Light is emitted from the sheet at a certain degree. Then, in this case, the light emitted from the light emitting surface of the backlight is substantially most concentrated within an angle of about 40 degrees from the normal direction dropped onto the light emitting surface, and as a result, the light is measured from the normal direction. The brightness is
The number is increased as compared with the case where the sheet is not provided.
【００２６】同様に、図１３に示したように前記シ−ト
をポリカ−ボネートで作り、プリズムの頂角を１２０度
にした場合に於いては、入射角０度で前記シ−トに入射
した光線は出射角２２．７度で前記シ−トより出光し、
入射角３０度で前記シ−トに入射した光線は出射角１
１．２度で前記シ−トより出光し、入射角６０度で前記
シ−トに入射した光線は出射角３４．８度で前記シ−ト
より出光する。そして、この場合のバックライトの出光
面から出光する光は実質的に前記出光面に降ろした法線
方向からの角度がほぼ４４度以内に最も集中し、その結
果、前記法線方向から測定した輝度が、前記シ−トを配
さない場合に比較して増加する。Similarly, when the sheet is made of polycarbonate as shown in FIG. 13 and the apex angle of the prism is 120 degrees, the sheet is incident on the sheet at an incident angle of 0 degree. The emitted light is emitted from the sheet at an emission angle of 22.7 degrees,
A light ray that enters the sheet at an incident angle of 30 degrees has an exit angle of 1
A light beam emitted from the sheet at 1.2 degrees and a light beam incident on the sheet at an incident angle of 60 degrees exits from the sheet at an emission angle of 34.8 degrees. Then, in this case, the light emitted from the light emitting surface of the backlight is substantially most concentrated within an angle of about 44 degrees from the normal direction dropped onto the light emitting surface, and as a result, it is measured from the normal direction. The brightness increases as compared with the case where the sheet is not provided.
【００２７】この様に、前記シ−トのプリズムの頂角を
コントロ−ルすることによって、面状発光体の出光面か
ら出光する光の指向性を制御することが出来る。As described above, by controlling the apex angle of the sheet prism, it is possible to control the directivity of the light emitted from the light emitting surface of the planar light emitting body.
【００２８】[0028]
【発明の効果】本発明は比較的小型で、充分な輝度を得
られ、出光面に降ろした法線方向に対しては消費電力−
輝度変換効率が大なバックライトとして使用できる。EFFECTS OF THE INVENTION The present invention is comparatively small in size, can obtain sufficient brightness, and consumes less power in the direction normal to the light exit surface.
It can be used as a backlight with high luminance conversion efficiency.
【００２９】[0029]
【実施例】次に比較例及び実施例で本発明を更に詳述す
る。図５に示すような厚さ２．０ｍｍの長方形導光板
（２２５ｍｍ×１２７ｍｍ）の短手の端部に、直径４．
８ｍｍの太さの冷陰極蛍光管（ハリソン電機株式会社製
ノ−マル管）を配置し、導光板に接する部分に２ｍｍの
スリットを持つ筒型アルミ反射器の内面に光拡散フィル
ムをラミネ−トしたもので覆い、スリットから出光した
光が導光板の端部から導光板に入光するように配置し
た。一方、導光板面上に被覆する光拡散物質（チタンホ
ワイトを含む塗料）は、円形のドットパタ−ンを１．２
ｍｍピッチでスクリ−ン印刷したものであり下記の条件
で作成して用いた。光拡散物質の被覆率が、最小の地点
（冷陰極蛍光管側）で６％、最大の地点で８０％、その
中間ではこれらの比率を順次増加した値となるように作
図した。EXAMPLES Next, the present invention will be described in more detail with reference to Comparative Examples and Examples. A rectangular light guide plate (225 mm × 127 mm) having a thickness of 2.0 mm as shown in FIG.
A cold-cathode fluorescent tube (Normal tube manufactured by Harrison Electric Co., Ltd.) having a thickness of 8 mm is arranged, and a light diffusion film is laminated on the inner surface of a cylindrical aluminum reflector having a 2 mm slit in a portion in contact with the light guide plate. It was arranged so that the light emitted from the slit would enter the light guide plate from the end portion of the light guide plate. On the other hand, the light-diffusing substance (paint containing titanium white) coated on the surface of the light guide plate has a circular dot pattern of 1.2.
The screen was printed at a mm pitch, and was prepared and used under the following conditions. It was plotted so that the coverage of the light diffusing substance was 6% at the minimum point (cold cathode fluorescent tube side), 80% at the maximum point, and these ratios were sequentially increased in the middle.
【００３０】さらに、導光板の出光面側に光拡散フィル
ム（辻本電機製作所Ｄ−２０４）を１枚配置した。冷陰
極管に、インバ−タより３０ＫＨｚの交番電圧をかけて
一定電流で駆動させたときの面輝度を、輝度計（トプコ
ンＢＭ−７）により視野角２度、出光面に降ろした法線
方向に対して、出光面から輝度計までの距離４０ｃｍで
測定したところ１９２ｃｄ／ｍ２であった（比較例
１）。Further, one light diffusion film (Tsujimoto Denki Seisakusho D-204) was arranged on the light emitting surface side of the light guide plate. The surface luminance when an alternating voltage of 30 KHz is applied from the inverter to the cold-cathode tube and driven at a constant current, the viewing angle is 2 degrees with the luminance meter (Topcon BM-7), and the normal direction is lowered to the light emitting surface. On the other hand, when measured at a distance of 40 cm from the light emitting surface to the luminance meter, it was 192 cd / m 2 (Comparative Example 1).
【００３１】前記光拡散フィルムの上に、市販の、ポリ
カ−ボネートからなる頂角が９０度の互いに平行な直線
状プリズムを多数有する、直線状プリズムの隣り合った
頂稜と頂稜との間隔が３５０μｍの間隔になるように加
工した厚さ３６０μｍのシ−トを直線状プリズムが外側
になるようにバックライトの出光面側に１枚配置した以
外は比較例１と同一の装置、条件、で操作し、測定した
輝度は３０７ｃｄ／ｍ２であった（実施例１）。On the light-diffusing film, there are a large number of commercially available linear prisms made of polycarbonate and having parallel apex angles of 90 degrees, and the distance between adjacent apexes of the linear prisms. With the same apparatus and conditions as in Comparative Example 1 except that one sheet having a thickness of 360 μm processed to have an interval of 350 μm is arranged on the light emitting surface side of the backlight so that the linear prism is on the outside. The brightness measured according to Example 1 was 307 cd / m 2 (Example 1).
【００３２】更に直線状プリズムが内側になるようにバ
ックライトの出光面側に１枚配置した以外は以外は実施
例１と同一の装置、条件、で操作し、測定した輝度は１
５ｃｄ／ｍ２であった（比較例２）。更にプリズム状の
突起の頂角を７０度にした直線状プリズムを用いた以外
は実施例１と同一の装置、条件、で操作し、測定した輝
度は２４５ｃｄ／ｍ２であった（実施例２）。更にプリ
ズム状の突起の頂角を１２０度にした以外は実施例１と
同一の装置、条件、で操作し、測定した輝度は３３０ｃ
ｄ／ｍ２であった（実施例３）。Further, the brightness was measured by operating under the same apparatus and conditions as in Example 1 except that one linear prism was arranged on the light emitting surface side of the backlight so that the prism was inside.
It was 5 cd / m 2 (Comparative Example 2). Furthermore, the brightness was 245 cd / m 2 as measured by operating under the same apparatus and conditions as in Example 1 except that a linear prism in which the apex angle of the prismatic projection was 70 degrees was used (Example 2 ). Further, the brightness measured at the same apparatus and conditions as in Example 1 was 330c except that the apex angle of the prismatic protrusion was 120 degrees.
It was d / m 2 (Example 3).
【００３３】次に、バックライトの配光特性を調べるた
めに、比較例１、実施例１、実施例２、について、冷陰
極管に、インバ−タより３０ＫＨｚの交番電圧をかけて
一定電流で駆動させたときの面輝度を、輝度計（トプコ
ンＢＭ−７）により視野角２度で、図１４に示すように
出光面に降ろした法線方向に対しての角度を０度から７
０度まで変化させ、出光面から輝度計までの距離４０cm
で測定したときの輝度の値を図１５に示した。この図か
ら、本発明のバックライトを用いると輝度が増加し、光
の指向性が顕著であることが判る。Next, in order to investigate the light distribution characteristics of the backlight, in Comparative Example 1, Example 1 and Example 2, an alternating voltage of 30 KHz was applied from the inverter to the cold cathode tube at a constant current. With respect to the surface luminance when driven, a luminance meter (Topcon BM-7) has a viewing angle of 2 degrees, and an angle with respect to the normal direction lowered to the light emitting surface from 0 degree to 7 degrees as shown in FIG.
The distance from the light emitting surface to the luminance meter is 40 cm
The value of the brightness when measured in FIG. From this figure, it can be seen that when the backlight of the present invention is used, the brightness is increased and the directivity of light is remarkable.
【図１】１灯型エッジライト方式のバックライトの一例
を示す斜視図FIG. 1 is a perspective view showing an example of a one-light type edge light type backlight.
【図２】１灯型エッジライト方式のバックライトの一例
を示す断面図FIG. 2 is a cross-sectional view showing an example of a one-light type edge light type backlight.
【図３】２灯型エッジライト方式のバックライトの一例
を示す斜視図FIG. 3 is a perspective view showing an example of a two-light type edge light type backlight.
【図４】１灯型エッジライト方式のバックライトの一例
を示す断面図FIG. 4 is a cross-sectional view showing an example of a one-light edge-light type backlight.
【図５】本発明の一実施態様の斜視図FIG. 5 is a perspective view of an embodiment of the present invention.
【図６】本発明の一実施態様の断面図FIG. 6 is a cross-sectional view of one embodiment of the present invention.
【図７】本発明の一実施態様の斜視図FIG. 7 is a perspective view of an embodiment of the present invention.
【図８】本発明の一実施態様の断面図FIG. 8 is a cross-sectional view of one embodiment of the present invention.
【図９】本発明で用いるシ−トの斜視図FIG. 9 is a perspective view of a sheet used in the present invention.
【図１０】光線追跡の一例を示す図FIG. 10 is a diagram showing an example of ray tracing.
【図１１】光線追跡の一例を示す図FIG. 11 is a diagram showing an example of ray tracing.
【図１２】プリズム頂角９０度の場合の例を示す図FIG. 12 is a diagram showing an example in which the prism vertical angle is 90 degrees.
【図１３】プリズム頂角１２０度の場合の例を示す図FIG. 13 is a diagram showing an example in which the prism vertical angle is 120 degrees.
【図１４】本発明で用いた測定方法の概念図FIG. 14 is a conceptual diagram of a measuring method used in the present invention.
【図１５】出射光輝度の角度分布を示す図FIG. 15 is a diagram showing an angular distribution of emitted light brightness.
１：導光板 ２：光拡散板 ３：反射板 ４：線状光源 ５：反射器 ６：光拡散物質 ７：直線状プリズムを持つシ−ト ８：直線状頂稜 ９：プリズムの頂角 １０：バックライト １１：輝度計 １２：出光面に降ろした法線方向に対しての角度 １３：出光面に降ろした法線 1: Light guide plate 2: Light diffusing plate 3: Reflecting plate 4: Linear light source 5: Reflector 6: Light diffusing material 7: Sheet with linear prism 8: Linear apex edge 9: Vertical angle of prism 10 : Backlight 11: Luminance meter 12: Angle with respect to the direction of the normal line lowered to the light emitting surface 13: Normal line lowered to the light emitting surface
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成３年１０月２９日[Submission date] October 29, 1991
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００７[Correction target item name] 0007
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００７】即ち本発明は、透光性材料からなる導光板
の一方の広い面に、該導光板材料よりも屈折率が大きい
光拡散物質を部分的に被覆し、その面を鏡面ないし光反
射板で覆い、前記導光板の少なくとも一側面端部にこれ
に近接した線状光源を有するパネル用バックライトに於
いて、導光板の出光面側に、同一面に微細な間隔で直線
状頂稜を持つプリズムが、頂稜がほぼ平行となる状態で
多数有する透光性材料からなるシートを、頂稜面が外側
になるように、出光面側に１枚以上配置したパネル用バ
ックライトに関するものである。 次に本発明を図面に
基づいて詳述する。図５は、導光板の一端部に光源を持
つエッジライト方式の一実施態様の斜視図であり、図６
はその断面図である。同様に図７は、導光板の二端部に
光源を持つエッジライト方式の一実施態様の斜視図であ
り、図８はその断面図である。That is, according to the present invention, one wide surface of a light guide plate made of a translucent material is partially covered with a light diffusing substance having a refractive index higher than that of the light guide plate material, and the surface is mirror-finished or light-reflecting. In a backlight for a panel, which is covered with a plate and has a linear light source near at least one side surface end of the light guide plate, a straight top edge is formed on the same surface of the light guide plate at a minute interval on the light emitting surface side. Related to a panel backlight in which one or more sheets of translucent material having a plurality of prisms having a substantially parallel top edge are arranged on the light emitting surface side so that the top edge surface is on the outside. Is. Next, the present invention will be described in detail with reference to the drawings. FIG. 5 is a perspective view of an embodiment of an edge light system having a light source at one end of a light guide plate.
Is a sectional view thereof. Similarly, FIG. 7 is a perspective view of an embodiment of an edge light system having light sources at two ends of the light guide plate, and FIG. 8 is a sectional view thereof.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１４[Correction target item name] 0014
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１４】本発明における前記条件を更に詳述する
と、前記したシート（図中７）は透光性材料からなるも
のであれば特に限定されないが、例えばメタクリル酸エ
ステル、ポリカーボネイト、ポリ塩化ビニル、ポリスチ
レン、ポリアミド、ポリエチレンテレフタレート（ＰＥ
Ｔ）などのポリエステル、ポリエチレン、ポリプロピレ
ン、繊維素系樹脂ガラス等である。The above-mentioned conditions in the present invention will be described in more detail. The above-mentioned sheet (7 in the figure) is not particularly limited as long as it is made of a translucent material. For example, methacrylic acid ester, polycarbonate, polyvinyl chloride, polystyrene. , Polyamide, polyethylene terephthalate (PE
T) and other polyesters, polyethylene, polypropylene, fiber-based resin glass, and the like.
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１８[Correction target item name] 0018
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１８】本発明で用いるシートを成形する方法は特
に限定されるものではなく、例えば熱プレスによる金型
成型加工、エンボス加工、鋳型加工、化学処理等の方法
で実質的に同形の直線状プリズムを微細な間隔で互いに
平行な状態で多数有するように成形可能な方法であれば
良い。尚、製造上の理由から頂稜には若干のだれが生じ
るが、本発明の効果が認められる範囲であれば良い。
又、前記した透光性フィルム（ベースフィルム）の上に
ベースフィルムとは同一材質か、又は、異質の透光性材
質（例えばアクリル系樹脂などの紫外線硬化樹脂等）を
印刷等の方法によって直線状凸型を微細な間隔で多数有
するように成形しても良い。The method of molding the sheet used in the present invention is not particularly limited, and for example, a linear prism of substantially the same shape can be formed by a method such as die molding by hot pressing, embossing, casting, or chemical treatment. Any method can be used as long as it can be molded so as to have a large number of fine particles in parallel with each other. It should be noted that although a slight sag occurs at the apex for manufacturing reasons, it may be within the range in which the effect of the present invention can be recognized.
In addition, the same material as the base film or a different light-transmitting material (for example, an ultraviolet curable resin such as an acrylic resin) is linearly printed on the above-mentioned light-transmitting film (base film) by a method such as printing. You may shape | mold so that it may have many convex protrusions with a minute space | interval.
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００３２[Name of item to be corrected] 0032
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００３２】更に直線状プリズムが内側になるようにバ
ックライトの出光面側に１枚配置した以外は以外は実施
例１と同一の装置、条件、で操作し、測定した輝度は１
５ｃｄ／ｍ２であった（比較例２）。更にプリズム状の
突起の頂角を７０度にした直線状プリズムを用いた以外
は実施例１と同一の装置、条件、で操作し、測定した輝
度は２４５ｃｄ／ｍ２であった（実施例２）。更にプリ
ズム状の突起の頂角を１２０度にした以外は実施例１と
同一の装置、条件、で操作し、測定した輝度は３３０ｃ
ｄ／ｍ２であった（実施例３）。前記光拡散フィルムの
上に、厚さ５０μｍのＰＥＴのベースフィルムの上に印
刷法によって紫外線硬化樹脂（アクリル系樹脂）で多数
の直線状凸部を、凸部の底面の直径が５０μｍ、底面か
ら凸部までの高さが２５μｍ、凸部と凸部の間隔が５０
μｍになるように形成したシートを直線状凸部が外側に
なるようにバックライトの出光面側に１枚配置した以外
は比較例１と同一の装置、条件、で操作し、測定した揮
度は２３５ｃｄ／ｍ２であった（実施例４）。Further, the brightness was measured by operating under the same apparatus and conditions as in Example 1 except that one linear prism was arranged on the light emitting surface side of the backlight so that the prism was inside.
It was 5 cd / m 2 (Comparative Example 2). Furthermore, the brightness was 245 cd / m 2 as measured by operating under the same apparatus and conditions as in Example 1 except that a linear prism in which the apex angle of the prismatic projection was 70 degrees was used (Example 2 ). Further, the brightness measured at the same apparatus and conditions as in Example 1 was 330c except that the apex angle of the prismatic protrusion was 120 degrees.
It was d / m 2 (Example 3). On the light-diffusing film, a large number of linear convex portions made of a UV curable resin (acrylic resin) were formed on a PET base film having a thickness of 50 μm by a printing method, and the diameter of the bottom surface of the convex portion was 50 μm. The height to the convex part is 25 μm, and the space between the convex parts is 50 μm.
Volatility measured by operating under the same apparatus and conditions as in Comparative Example 1 except that one sheet formed so as to have a thickness of μm was arranged on the light emitting surface side of the backlight so that the linear convex portion was on the outside. Was 235 cd / m 2 (Example 4).
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】図 ４[Name of item to be corrected] Figure 4
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図４】２灯型エッジライト方式のバックライトの一例
を示す断面図 ─────────────────────────────────────────────────────
FIG. 4 is a cross-sectional view showing an example of a backlight of a two-lamp type edge light system ──────────────────────────────── ──────────────────────
【手続補正書】[Procedure amendment]
【提出日】平成４年１月１７日[Submission date] January 17, 1992
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００２[Name of item to be corrected] 0002
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００２】[0002]
【従来の技術】近時、ラップトップ型又は、ブック型の
ワードプロセッサーやコンピュータ等の表示装置とし
て、薄型でしかも見易いバックライト機構を有する液晶
表示装置が用いられている。このようなバックライトに
は、図１に示すように透光性の導光板の一端部に、蛍光
管のような線状光源を併設する１灯型エッジライト方
式、図３に示すように透光性の導光板の対向する二端部
に、蛍光管のような線状光源を併設する２灯型エッジラ
イト方式、がよく用いられる。このエッジライト方式の
場合、図２又は図４に示すように、導光板の一方の面に
この導光板材料よりも屈折率が大きい光拡散物質を部分
的に被覆し、その面のほぼ全面を光拡散反射板で覆うよ
うに配置されたものが多い。2. Description of the Related Art Recently, a liquid crystal display device having a thin and easy-to-read backlight mechanism has been used as a display device for a laptop or book type word processor, a computer or the like. For such a backlight, a one-lamp type edge light system in which a linear light source such as a fluorescent tube is provided at one end of a light-transmitting light guide plate as shown in FIG. 1, and as shown in FIG. A two-lamp type edge light system in which a linear light source such as a fluorescent tube is provided at two opposite ends of a light guide plate is often used. For this edge light system, as shown in FIG. 2 or FIG. 4, a light diffusing material having a refractive index greater than the light guide plate material on one surface of the light guide plate is partially coated, substantially the entire surface of the surface Many are arranged so as to be covered with a light diffusion reflector.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１０[Correction target item name] 0010
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１０】鏡面ないし光反射板、例えば、光拡散反射
板（図中３）は光拡散物質を被覆した導光板の面のほぼ
全面を覆うように配置するが、導光板の線状光源を近接
させていない残りの端面部のほぼ全面を覆うように配置
すると光の利用効率及び均一な面状発光を得る点で更に
良い。A mirror surface or a light reflecting plate, for example, a light diffusing reflecting plate (3 in the figure) is arranged so as to cover almost the entire surface of the light guiding plate coated with the light diffusing substance, but the linear light source of the light guiding plate is close to It is more preferable to dispose so as to cover almost the entire surface of the remaining end face portion which has not been performed in terms of light utilization efficiency and uniform planar light emission.
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１１[Correction target item name] 0011
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１１】７は透光性材料からなるシート（以下単に
シートと称する）で、同一面に微細な間隔で互いに平行
な直線状頂稜を多数有するもので、頂稜面が外側（導光
板と相対する面と反対側）になるように配置することに
より、バックライトの出光面より出光した光の指向性を
変化させ、出光面に降ろした法線方向近傍に対する指向
性をより強くさせるものである。前記直線状頂稜部が線
状光源の中心軸と平行になるように配置しても良いし、
直角になるように配置しても良い。Reference numeral 7 denotes a sheet made of a translucent material (hereinafter, simply referred to as a sheet), which has a large number of linear apexes parallel to each other on the same surface at fine intervals. By arranging it so that it is on the side opposite to the facing surface), the directivity of the light emitted from the light emitting surface of the backlight is changed, and the directivity in the vicinity of the normal direction dropped on the light emitting surface is made stronger. is there. It may be arranged such that the linear apex portion is parallel to the central axis of the linear light source,
You may arrange so that it may become a right angle.
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２９[Name of item to be corrected] 0029
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００２９】[0029]
【実施例】次に比較例及び実施例で本発明を更に詳述す
る。図５又は６に示すような厚さ２．０ｍｍの長方形導
光板（２２５ｍｍ×１２７ｍｍ）（図中１）の短手の端
部に、直径４．８ｍｍの太さの冷陰極蛍光管（ハリソン
電機株式会社製ノーマル管）（図中４）を配置し、導光
板に接する部分に２ｍｍのスリットを持つ筒型アルミ反
射器の内面に光拡散フィルムをラミネートしたもので覆
い、スリットから出光した光が導光板の端部から導光板
に入光するように配置した。一方、導光板面上に被覆す
る光拡散物質（チタンホワイトを含む塗料）（図中６）
は、円形のドットパターンを１．２ｍｍピッチでスクリ
ーン印刷したものであり下記の条件で作成して用いた。
光拡散物質の被覆率が、最小の地点（冷陰極蛍光管側）
で６％、最大の地点で８０％、その中間ではこれらの比
率を順次増加した値となるように作図した。EXAMPLES Next, the present invention will be described in more detail with reference to Comparative Examples and Examples. At the short end of a rectangular light guide plate (225 mm x 127 mm) ( 225 mm x 127 mm) (1 in the figure ) with a thickness of 2.0 mm as shown in Fig. 5 or 6 , a cold cathode fluorescent tube with a thickness of 4.8 mm (Harrison Electric) ( Normal tube manufactured by Co., Ltd.) (4 in the figure) is placed, and a light diffusion film is laminated on the inner surface of a cylindrical aluminum reflector that has a slit of 2 mm in the part in contact with the light guide plate. The light guide plate is arranged so that light enters the light guide plate from the end thereof. On the other hand, a light diffusing substance (paint containing titanium white) covering the surface of the light guide plate (6 in the figure)
Is a circular dot pattern screen-printed at a pitch of 1.2 mm, and was prepared and used under the following conditions.
Point where the light diffusing substance coverage is the minimum (cold cathode fluorescent tube side)
6% at the maximum, 80% at the maximum point, and in the middle of them, these ratios were sequentially increased.
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００３０[Name of item to be corrected] 0030
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００３０】さらに、導光板の出光面側に光拡散フィル
ム（辻本電機製作所Ｄ−２０４）（図中２）を１枚配置
した。又、導光板の光拡散物質を被覆した面側に光拡散
反射板（図中３）を配置した。冷陰極管に、インバータ
より３０ＫＨｚの交番電圧をかけて一定電流で駆動させ
たときの面輝度を、輝度計（トプコンＢＭ−７）により
視野角２度、出光面に降ろした法線方向に対して、出光
面から輝度計までの距離４０ｃｍで測定したところ１９
２ｃｄ／ｍ２であった（比較例１）。Further, one light diffusion film (Tsujimoto Denki Seisakusho D-204) (2 in the figure) was arranged on the light emitting surface side of the light guide plate. In addition, light is diffused to the side of the light guide plate that is coated with the light diffusing substance.
A reflector (3 in the figure) was placed. The surface luminance of the cold-cathode tube when driven at a constant current by applying an alternating voltage of 30 KHz from the inverter was measured with a luminance meter (Topcon BM-7) at a viewing angle of 2 degrees, with respect to the normal direction lowered to the light emitting surface. And measured at a distance of 40 cm from the light emitting surface to the luminance meter, 19
It was 2 cd / m 2 (Comparative Example 1).
Claims (3)
に、該導光板材料よりも屈折率が大きい光拡散物質を部
分的に被覆し、その面を鏡面ないし光反射板で覆い、前
記導光板の少なくとも一側面端部にこれに近接した線状
光源を有するパネル用バックライトに於いて、導光板の
出光面側に、同一面に微細な間隔で直線状頂稜を持つプ
リズムが、頂稜がほぼ平行となる状態で多数有する透光
性材料からなるシ−トを、頂稜面が外側になるように、
出光面側に１枚以上配置したパネル用バックライト。1. A wide surface of a light guide plate made of a translucent material is partially covered with a light diffusing substance having a refractive index higher than that of the light guide plate material, and the surface is covered with a mirror surface or a light reflecting plate. In a backlight for a panel having a linear light source adjacent to at least one side surface end portion of the light guide plate, a prism having linear vertexes on the same surface on the light exit surface side of the light guide plate at fine intervals However, a sheet made of a translucent material having a large number of apexes in a state where the apexes are substantially parallel to each other so that the apex faces are on the outside.
A backlight for panels that is arranged on the light emitting surface side.
トを用いる請求項１記載のパネル用バックライト。2. A seam having an apex with an apex angle of 70 to 150 degrees.
The backlight for a panel according to claim 1, wherein a backlight is used.
１０００μｍであるシ−トを用いる請求項１又は２記載
のパネル用バックライト。3. The distance between adjacent apexes is 10 to 10.
The backlight for a panel according to claim 1, wherein a sheet having a thickness of 1000 μm is used.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3275022A JP3030792B2 (en) | 1991-09-27 | 1991-09-27 | Backlight |
| DE69220870T DE69220870T2 (en) | 1991-08-22 | 1992-08-21 | Rear lighting device |
| EP92114326A EP0534140B1 (en) | 1991-08-22 | 1992-08-21 | Backlighting device |
| US07/933,208 US5442523A (en) | 1991-08-22 | 1992-08-21 | Backlighting device |
| US08/466,747 US5730518A (en) | 1991-08-22 | 1995-06-06 | Backlighting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3275022A JP3030792B2 (en) | 1991-09-27 | 1991-09-27 | Backlight |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7140544A Division JPH08111106A (en) | 1995-06-07 | 1995-06-07 | Backlight |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05127159A true JPH05127159A (en) | 1993-05-25 |
| JP3030792B2 JP3030792B2 (en) | 2000-04-10 |
Family
ID=17549787
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3275022A Expired - Fee Related JP3030792B2 (en) | 1991-08-22 | 1991-09-27 | Backlight |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3030792B2 (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05203947A (en) * | 1992-01-24 | 1993-08-13 | Stanley Electric Co Ltd | Plane luminous body device |
| JPH05203950A (en) * | 1992-01-27 | 1993-08-13 | Sekisui Chem Co Ltd | Condenser sheet and panel light emitting device |
| JPH07239467A (en) * | 1994-02-28 | 1995-09-12 | Nec Corp | Transmission type liquid crystal display device |
| JPH08111106A (en) * | 1995-06-07 | 1996-04-30 | Tosoh Corp | Backlight |
| US5521725A (en) * | 1993-11-05 | 1996-05-28 | Alliedsignal Inc. | Illumination system employing an array of microprisms |
| US5555329A (en) * | 1993-11-05 | 1996-09-10 | Alliesignal Inc. | Light directing optical structure |
| KR19980021185A (en) * | 1996-09-13 | 1998-06-25 | 김광호 | Backlight of liquid crystal display |
| US5980054A (en) * | 1996-05-09 | 1999-11-09 | Matsushita Electric Industrial Co., Ltd. | Panel-form illuminating system |
| US5986727A (en) * | 1996-04-05 | 1999-11-16 | Matsushita Electric Industrial Co., Ltd. | Back light illuminator for liquid crystal display apparatus |
| US6129439A (en) * | 1993-11-05 | 2000-10-10 | Alliedsignal Inc. | Illumination system employing an array of multi-faceted microprisms |
| US6312787B1 (en) | 1995-06-14 | 2001-11-06 | Mitsubishi Rayon Co., Ltd. | Resin sheet, process and apparatus for producing same, surface light source element and laminate |
| JP2008528755A (en) * | 2005-01-27 | 2008-07-31 | コーロン インダストリーズ インコーポレイテッド／コリア | Prism layer forming composition and prism film produced therefrom |
| US7543973B2 (en) | 2006-04-17 | 2009-06-09 | Citizen Electronics Co., Ltd. | Light guide plate, method of manufacturing light guide plate and backlight with the light guide plate |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5357068A (en) * | 1976-11-02 | 1978-05-24 | Eko Kk | Photoconductive plate for liquid crystal clock |
| JPS58109786U (en) * | 1982-01-20 | 1983-07-26 | カルソニックカンセイ株式会社 | Display panel lighting device |
| JPH01245220A (en) * | 1988-03-28 | 1989-09-29 | Tosoh Corp | Liquid crystal display device |
| JP3069184U (en) * | 1999-11-24 | 2000-06-06 | 株式会社金城興業 | Construction machine combined type crusher |
-
1991
- 1991-09-27 JP JP3275022A patent/JP3030792B2/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5357068A (en) * | 1976-11-02 | 1978-05-24 | Eko Kk | Photoconductive plate for liquid crystal clock |
| JPS58109786U (en) * | 1982-01-20 | 1983-07-26 | カルソニックカンセイ株式会社 | Display panel lighting device |
| JPH01245220A (en) * | 1988-03-28 | 1989-09-29 | Tosoh Corp | Liquid crystal display device |
| JP3069184U (en) * | 1999-11-24 | 2000-06-06 | 株式会社金城興業 | Construction machine combined type crusher |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05203947A (en) * | 1992-01-24 | 1993-08-13 | Stanley Electric Co Ltd | Plane luminous body device |
| JPH05203950A (en) * | 1992-01-27 | 1993-08-13 | Sekisui Chem Co Ltd | Condenser sheet and panel light emitting device |
| US5521725A (en) * | 1993-11-05 | 1996-05-28 | Alliedsignal Inc. | Illumination system employing an array of microprisms |
| US5555329A (en) * | 1993-11-05 | 1996-09-10 | Alliesignal Inc. | Light directing optical structure |
| US6129439A (en) * | 1993-11-05 | 2000-10-10 | Alliedsignal Inc. | Illumination system employing an array of multi-faceted microprisms |
| JPH07239467A (en) * | 1994-02-28 | 1995-09-12 | Nec Corp | Transmission type liquid crystal display device |
| JPH08111106A (en) * | 1995-06-07 | 1996-04-30 | Tosoh Corp | Backlight |
| US6312787B1 (en) | 1995-06-14 | 2001-11-06 | Mitsubishi Rayon Co., Ltd. | Resin sheet, process and apparatus for producing same, surface light source element and laminate |
| US5986727A (en) * | 1996-04-05 | 1999-11-16 | Matsushita Electric Industrial Co., Ltd. | Back light illuminator for liquid crystal display apparatus |
| US6068382A (en) * | 1996-05-09 | 2000-05-30 | Matsushita Electric Industrial Co., Ltd. | Panel-form illuminating system |
| US5980054A (en) * | 1996-05-09 | 1999-11-09 | Matsushita Electric Industrial Co., Ltd. | Panel-form illuminating system |
| KR19980021185A (en) * | 1996-09-13 | 1998-06-25 | 김광호 | Backlight of liquid crystal display |
| JP2008528755A (en) * | 2005-01-27 | 2008-07-31 | コーロン インダストリーズ インコーポレイテッド／コリア | Prism layer forming composition and prism film produced therefrom |
| JP4688109B2 (en) * | 2005-01-27 | 2011-05-25 | コーロン インダストリーズ インク | Prism layer forming composition and prism film produced therefrom |
| US7543973B2 (en) | 2006-04-17 | 2009-06-09 | Citizen Electronics Co., Ltd. | Light guide plate, method of manufacturing light guide plate and backlight with the light guide plate |
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| Publication number | Publication date |
|---|---|
| JP3030792B2 (en) | 2000-04-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |