JPH06331985A - Surface light source - Google Patents
Surface light sourceInfo
- Publication number
- JPH06331985A JPH06331985A JP5143060A JP14306093A JPH06331985A JP H06331985 A JPH06331985 A JP H06331985A JP 5143060 A JP5143060 A JP 5143060A JP 14306093 A JP14306093 A JP 14306093A JP H06331985 A JPH06331985 A JP H06331985A
- Authority
- JP
- Japan
- Prior art keywords
- light source
- guide plate
- light guide
- light
- curved surface
- 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.)
- Withdrawn
Links
Landscapes
- Light Guides In General And Applications Therefor (AREA)
- Liquid Crystal (AREA)
- Planar Illumination Modules (AREA)
Abstract
(57)【要約】
【目的】 線光源からの光を効率よく利用して、高輝度
の面光源を得ることのできる面光源装置を提供する。
【構成】 下面に光拡散透過部の設けられた透明な平板
の一側面の上面縁が面取りされて凹曲面を呈するととも
に下面縁が面取りされて凸曲面を呈する導光板１と、導
光板１の凹曲面全面と密着するように配置された線光源
２とからなる面光源ユニットを備え、導光板１の凹曲面
の弧の長さが線光源２の円周の１／４〜１／２であり、
凹曲面の上端点Ａと下端点Ｂとを結ぶ弦ＡＢと導光板１
上面の延長線との間になす角度が30〜60°である。
(57) [Summary] [Object] To provide a surface light source device capable of obtaining a high brightness surface light source by efficiently utilizing light from a linear light source. A light guide plate (1) having a concave curved surface with a chamfered upper surface edge of one side surface of a transparent flat plate having a light diffusing and transmitting portion on a lower surface, and a convex curved surface with a chamfered lower surface edge. A surface light source unit including a linear light source 2 arranged in close contact with the entire concave curved surface is provided, and the arc length of the concave curved surface of the light guide plate 1 is 1/4 to 1/2 of the circumference of the linear light source 2. Yes,
The string AB connecting the upper end point A and the lower end point B of the concave curved surface and the light guide plate 1
The angle formed between the extension line of the upper surface is 30 to 60 °.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、液晶ディスプレイなど
に使用される薄型の面光源装置に関するものであり、と
くに高輝度の面光源の得られるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin surface light source device used in a liquid crystal display or the like, and particularly to a surface light source having high brightness.
【０００２】[0002]
【従来の技術】従来より、透明な導光板１の一側面に線
光源２を配置し、導光板１の下面に光拡散透過部を設け
た面光源装置があった（図５参照）。また、特開平2-27
2486号公報には、下面に拡散透過部を有する導光板１を
拡散板５と反射板６との間に挟持し、導光板１の上面を
略Ｖ字状の凹面となして拡散板５への出射面となし、導
光板１の少なくとも一方の端部側に線光源２を配置し、
線光源２に対応する導光板１の端面を線光源２を部分的
に取り囲む曲面となすと共に、この曲面と共に線光源２
を取り囲み反射膜４を内側に形成したホルダ３を拡散板
５に固定し、導光板１の曲面とホルダ３の反射面とで線
光源２を収容する部分を形成した面光源装置が開示され
ている（図６参照）。2. Description of the Related Art Conventionally, there is a surface light source device in which a linear light source 2 is arranged on one side surface of a transparent light guide plate 1 and a light diffusion / transmission part is provided on the lower surface of the light guide plate 1 (see FIG. 5). In addition, JP-A-2-27
In Japanese Patent No. 2486, a light guide plate 1 having a diffusing and transmitting portion on its lower surface is sandwiched between a diffuser plate 5 and a reflecting plate 6, and the upper surface of the light guide plate 1 is formed into a substantially V-shaped concave surface to the diffuser plate 5. And the line light source 2 is arranged on at least one end side of the light guide plate 1.
The end surface of the light guide plate 1 corresponding to the linear light source 2 is formed as a curved surface that partially surrounds the linear light source 2, and the linear light source 2 is formed together with this curved surface.
A surface light source device is disclosed in which a holder 3 having a reflective film 4 formed inside is fixed to a diffusion plate 5 and a curved surface of the light guide plate 1 and a reflection surface of the holder 3 form a portion for accommodating the linear light source 2. (See Figure 6).
【０００３】[0003]
【発明が解決しようとする課題】しかし、これらの面光
源装置では、導光板の側面と線光源との間に空気層が介
在して線光源から発した光の導光板内への入射量が制限
されるため、面発光の効率が悪く、輝度も低いという問
題があった。また、特開平2−272486号公報に開示され
た面光源装置では、次の問題点もあった。すなわち、特
開平2−272486号公報に開示された面光源装置では、導
光板の両端面がＬ字型断面に形成されており、そのコー
ナー部のみが略四半円形状の曲面を持つように形成され
ている。したがって、導光板内に入射した光のうち導光
板の下面に対して垂直に近い角度で入射した光が全反射
を行わずに、そのまま導光板下面から出射してしまうこ
とになり、面発光の効率が悪く、輝度も低いという問題
があった。However, in these surface light source devices, there is an air layer between the side surface of the light guide plate and the line light source, and the amount of light emitted from the line light source entering the light guide plate is small. Because of the limitation, there are problems that the efficiency of surface emission is low and the brightness is low. Further, the surface light source device disclosed in Japanese Patent Laid-Open No. 2-272486 has the following problems. That is, in the surface light source device disclosed in Japanese Unexamined Patent Publication No. 2-272486, both end surfaces of the light guide plate are formed in an L-shaped cross section, and only the corners thereof are formed so as to have a substantially semicircular curved surface. Has been done. Therefore, of the light that has entered the light guide plate, the light that has entered the light guide plate at an angle that is nearly perpendicular to the lower surface of the light guide plate is not totally reflected and is directly emitted from the lower surface of the light guide plate. There were problems of low efficiency and low brightness.
【０００４】したがって、本発明は、上記の問題点を解
決し、線光源からの光を効率よく利用して、高輝度の面
光源を得ることのできる面光源装置を提供することを目
的とする。Therefore, an object of the present invention is to solve the above problems and to provide a surface light source device capable of obtaining a high brightness surface light source by efficiently utilizing light from a linear light source. .
【０００５】[0005]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明の面光源装置は、下面に光拡散透過部の設
けられた透明な平板の一側面の上面縁が面取りされて凹
曲面を呈するとともに下面縁が面取りされて凸曲面を呈
する導光板と、導光板の凹曲面全面と密着するように配
置された線光源とからなる面光源ユニットを備え、導光
板の凹曲面の弧の長さが線光源の円周の１／４〜１／２
であり、凹曲面の上端点Ａと下端点Ｂとを結ぶ弦ＡＢと
導光板上面の延長線との間になす角度が30〜60°である
ように構成した。In order to achieve the above object, the surface light source device of the present invention is such that one side surface of a transparent flat plate having a light diffusing and transmitting portion on its lower surface is chamfered to form a concave surface. The light guide plate having a curved surface and a convex curved surface with a chamfered lower edge, and a surface light source unit including a line light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate are provided. Is 1/4 to 1/2 of the circumference of the line light source
The angle between the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the extension line of the upper surface of the light guide plate is 30 to 60 °.
【０００６】また、本発明の面光源装置は、下面に光拡
散透過部の設けられた透明な平板の対向する二側面の上
面縁が面取りされて凹曲面を呈するとともに下面縁が面
取りされて凸曲面を呈する導光板と、導光板の凹曲面全
面と密着するようにそれぞれ配置された線光源とからな
る面光源ユニットを備え、導光板の凹曲面の弧の長さが
線光源の円周の１／４〜１／２であり、凹曲面の上端点
Ａと下端点Ｂとを結ぶ弦ＡＢと導光板上面の延長線との
間になす角度が30〜60°であるように構成することもで
きる。Further, in the surface light source device of the present invention, the upper surface edges of two opposing side surfaces of the transparent flat plate having the light diffusing and transmitting portion on the lower surface are chamfered to form a concave curved surface and the lower surface edges are chamfered to be convex. A surface light source unit including a light guide plate having a curved surface and a linear light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate is provided, and the arc length of the concave curved surface of the light guide plate is equal to the circumference of the linear light source. The angle is 1/4 to 1/2, and the angle formed between the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the extension line of the upper surface of the light guide plate is 30 to 60 °. You can also
【０００７】また、本発明の面光源装置は、下面に光拡
散透過部の設けられた透明な平板の一側面の上面縁が面
取りされて凹曲面を呈するとともに下面縁が面取りされ
て凸曲面を呈し且つ前記一側面に対向する他側面と上面
との間になす角度が５〜45°である導光板と、導光板の
凹曲面全面と密着するように配置された線光源とからな
る二個の面光源ユニットが、線光源側が両端となるよう
にして並設され、導光板の凹曲面の弧の長さが線光源の
円周の１／４〜１／２であり、凹曲面の上端点Ａと下端
点Ｂとを結ぶ弦ＡＢと導光板上面の延長線との間になす
角度が30〜60°であるように構成することもできる。Further, in the surface light source device of the present invention, the upper surface edge of one side of the transparent flat plate having the light diffusing and transmitting portion on the lower surface is chamfered to form a concave curved surface, and the lower surface edge is chamfered to form a convex curved surface. Two of a light guide plate, which is present and has an angle of 5 to 45 ° between the other side surface facing the one side surface and the upper surface, and a line light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate. Surface light source units are arranged side by side so that the linear light source side is at both ends, and the arc length of the concave curved surface of the light guide plate is 1/4 to 1/2 of the circumference of the linear light source. The angle between the chord AB connecting the end point A and the lower end point B and the extension line of the upper surface of the light guide plate may be 30 to 60 °.
【０００８】以下、本発明の面光源装置を図を用いてさ
らに詳しく説明する。図１は本発明の面光源装置の一実
施例を示す部分拡大断面図、図２は本発明の面光源装置
の一実施例を示す断面図、図３は本発明の面光源装置の
一実施例を示す断面図、図４は本発明の面光源装置の一
実施例を示す断面図である。１は導光板、２は線光源を
それぞれ示す。Hereinafter, the surface light source device of the present invention will be described in more detail with reference to the drawings. 1 is a partially enlarged sectional view showing an embodiment of a surface light source device of the present invention, FIG. 2 is a sectional view showing an embodiment of a surface light source device of the present invention, and FIG. 3 is an embodiment of the surface light source device of the present invention. FIG. 4 is a sectional view showing an example, and FIG. 4 is a sectional view showing an embodiment of the surface light source device of the present invention. Reference numeral 1 is a light guide plate, and 2 is a linear light source.
【０００９】導光板１の形状は、透明な平板の一側面の
上面縁が面取りされて凹曲面を呈するとともに下面縁が
面取りされて凸曲面を呈するものを用いる（図２参
照）。導光板１の凹曲面は、線光源２の外形の一部と一
致させることにより、その全面を線光源２と密着させる
ことができる。また、透明な平板の対向する２側面に面
取りをしたものを用いることもできる（図３参照）。As the shape of the light guide plate 1, a transparent flat plate having one side surface with a chamfered upper surface edge to form a concave curved surface and a lower surface edge to a chamfered surface to form a convex curved surface is used (see FIG. 2). The concave curved surface of the light guide plate 1 can be brought into close contact with the linear light source 2 by matching a part of the outer shape of the linear light source 2. It is also possible to use a transparent flat plate having two opposite side surfaces chamfered (see FIG. 3).
【００１０】また、凹曲面の弧の長さは線光源の円周の
１／４〜１／２であり、凹曲面の上端点Ａと下端点Ｂと
を結ぶ弦ＡＢと導光板１上面の延長線との間になす角度
（以下θ1とする。）は30〜60°である（図１参照）。
弧の長さが１／２以上になると、弧の両端付近から導光
板１内に入射した光の角度が導光板１の上面や線光源２
側の側面に対して垂直に近くなるので、全反射を行わず
にそのまま導光板１の外に出射してしまう。また、導光
板１を加工することも難しくなる。一方、弧の長さが１
／４以下だと、線光源２と導光板１とが密着する面積が
小さくなるので、入射する光の量が少なくなり充分な輝
度が得られない。また、角度θ1が60°以上になると、
導光板１内に入射した光の一部が全反射を行わずに直線
的に奥に進ので、線光源２の配置された側と反対側の側
面から光が出射する光が増える。一方、角度θ1が30°
以下になると、導光板１内に入射した光の一部が全反射
を行わずに直線的に下方に進むので、下面から出射する
光が増えてしまい効率が悪い。The arc length of the concave curved surface is 1/4 to 1/2 of the circumference of the linear light source, and the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the upper surface of the light guide plate 1 are formed. The angle formed with the extension line (hereinafter referred to as θ 1 ) is 30 to 60 ° (see FIG. 1).
When the length of the arc becomes 1/2 or more, the angle of the light entering the light guide plate 1 from the vicinity of both ends of the arc is such that the upper surface of the light guide plate 1 and the line light source 2
Since it is close to being perpendicular to the side surface on the side, the light is directly emitted to the outside of the light guide plate 1 without being totally reflected. Further, it becomes difficult to process the light guide plate 1. On the other hand, the length of the arc is 1
If it is / 4 or less, the area where the linear light source 2 and the light guide plate 1 are in close contact with each other becomes small, so that the amount of incident light becomes small and sufficient brightness cannot be obtained. Also, when the angle θ 1 becomes 60 ° or more,
Since a part of the light that has entered the light guide plate 1 travels straight inward without being totally reflected, the light emitted from the side surface opposite to the side where the linear light source 2 is arranged increases. On the other hand, the angle θ 1 is 30 °
In the following cases, a part of the light that has entered the light guide plate 1 linearly proceeds downward without being totally reflected, so that the light emitted from the lower surface increases and the efficiency is poor.
【００１１】また、上面および下面の縁が面取りされた
側面に対向する他側面を、上面との間に５〜45°の角度
（以下θ2とする。）をなすようにしてもよい。角度θ2
を５〜45°とすることによって、この側面から光が出射
することを防ぐことができる。角度θ2は45°以上にな
ると側面より光が出射してしまい、５°以下になると導
光板１を加工することが難しくなる。Further, the other side surface facing the chamfered side surface of the upper and lower surfaces may form an angle of 5 to 45 ° (hereinafter referred to as θ 2 ) with the upper surface. Angle θ 2
By setting 5 to 45 °, it is possible to prevent light from being emitted from this side surface. When the angle θ 2 is 45 ° or more, light is emitted from the side surface, and when it is 5 ° or less, it becomes difficult to process the light guide plate 1.
【００１２】また、導光板１の厚さおよび材質は、用途
に応じて適宜選択して用いられる。たとえば、液晶表示
装置のバックライトに適用される導光板１の場合には、
厚さ３〜５mm程度のものがとくに好ましく、アクリル樹
脂、ポリカーボネート樹脂、ポリ塩化ビニル樹脂または
ガラスなどの材質からなるものを用いるとよい。The thickness and material of the light guide plate 1 are appropriately selected and used according to the application. For example, in the case of the light guide plate 1 applied to the backlight of a liquid crystal display device,
Those having a thickness of about 3 to 5 mm are particularly preferable, and those made of a material such as acrylic resin, polycarbonate resin, polyvinyl chloride resin or glass may be used.
【００１３】線光源２としては、熱陰極線管や冷陰極線
管などの陰極線管が用いられ、直径はとくに２〜４mm程
度のものが好ましい。また、線光源２の導光板１と密着
していない残りの部分を覆うように反射シートを配置し
て、その内面の鏡面により線光源２からの光を導光板１
側に反射して効率よく利用できるようにしてもよい。A cathode ray tube such as a hot cathode ray tube or a cold cathode ray tube is used as the line light source 2, and a diameter of 2 to 4 mm is particularly preferable. Further, a reflection sheet is arranged so as to cover the remaining portion of the linear light source 2 that is not in close contact with the light guide plate 1, and the light from the linear light source 2 is reflected by the inner surface of the reflection sheet.
It may be reflected to the side so that it can be used efficiently.
【００１４】導光板１の下面には、線光源２からの光を
均一に配分する目的で、グラデーションパターンの光拡
散透過部（図示せず）が形成される。光拡散透過部の面
積率の変化には、たとえば、線光源２より遠ざかるにつ
れて面積率が大きくなるようなものがある。また、導光
板１の線光源２側から特定位置までは線光源２より遠ざ
かるにつれて面積率が大きくなり、特定位置からは面積
率が一定となるようなものもある。また、グラデーショ
ンパターンには、ドット状パターンで形成されるものや
ストライプ状パターンで形成されるものがある。光拡散
透過部としては、散乱物質を含有するインキを用いて、
スクリーン印刷することにより設けることができる。A light diffusion / transmission part (not shown) having a gradation pattern is formed on the lower surface of the light guide plate 1 for the purpose of uniformly distributing the light from the linear light source 2. The change of the area ratio of the light diffusion / transmission part may be such that the area ratio increases as the distance from the linear light source 2 increases. In addition, there is a type in which the area ratio increases from the linear light source 2 side of the light guide plate 1 to the specific position as the distance from the linear light source 2 increases, and the area ratio becomes constant from the specific position. In addition, the gradation pattern may be a dot pattern or a stripe pattern. As the light diffusion / transmission part, an ink containing a scattering substance is used,
It can be provided by screen printing.
【００１５】以上のような導光板１と線光源２とからな
る面光源ユニットが本願発明の面光源装置に組み込まれ
る。なお、二灯タイプの面光源ユニットは一灯タイプに
比べると光源が１つ多いので高輝度が得られるが、一方
の線光源２から導光板１内に入射した光の中の一部が、
他方の線光源２が配置された側面より出射して光のロス
が生ずる。そこで前記した角度θ2が５〜45°である一
灯タイプの面光源ユニットを二個一組として線光源２側
が両端となるように隣接させて面光源装置に組み込むこ
とによって、より高輝度でしかも効率のよい面発光を得
ることができる（図４参照）。The surface light source unit comprising the light guide plate 1 and the linear light source 2 as described above is incorporated in the surface light source device of the present invention. The two-lamp type surface light source unit has more light sources than the one-lamp type, so that high brightness can be obtained. However, a part of the light incident on the light guide plate 1 from one of the linear light sources 2 is
Light is emitted from the side surface on which the other linear light source 2 is arranged, and light loss occurs. Therefore, a set of two single-lamp type surface light source units having the above-mentioned angle θ 2 of 5 to 45 ° are installed in the surface light source device so as to be adjacent to each other so that the line light source 2 side is at both ends. Moreover, efficient surface emission can be obtained (see FIG. 4).
【００１６】本願発明の面光源装置では、上記の面光源
ユニットの他に、導光板１の上面側に拡散板を配置して
もよいし、導光板１の下面に反射板を配置してもよい
（図示せず）。In the surface light source device of the present invention, in addition to the above surface light source unit, a diffusion plate may be arranged on the upper surface side of the light guide plate 1, or a reflection plate may be arranged on the lower surface of the light guide plate 1. Good (not shown).
【００１７】[0017]
【作用】本発明の面光源装置は、上記のように構成され
るので、次の作用が得られる。すなわち、（１）線光源
と凹曲面を呈する導光板とが特定の位置関係で隙間なく
密着して配置されているため、線光源から導光体内への
光の入射が容易になる。（２）また、導光板の線光源が
配置された側面の下面縁が面取りされて凸曲面を呈する
ため、導光板内に入射した光のうち導光板の下面に対し
て垂直に近い角度で入射した光が導光板の中央方向に全
反射する。Since the surface light source device of the present invention is constructed as described above, the following effects can be obtained. That is, (1) the linear light source and the light guide plate having a concave curved surface are arranged in close contact with each other in a specific positional relationship without a gap, so that it becomes easy for light to enter the light guide body from the linear light source. (2) Since the lower edge of the side surface of the light guide plate on which the linear light source is arranged is chamfered to form a convex curved surface, the light entering the light guide plate is incident at an angle almost perpendicular to the lower surface of the light guide plate. The reflected light is totally reflected toward the center of the light guide plate.
【００１８】[0018]
【実施例】以下、本発明の面光源装置の実施例を示す。
線光源として、直径3.5mmの冷陰極線管を使用した。導
光板として、縦220mm、横160mm、厚さ４mmのアクリル樹
脂からなる透明な平板で、その一側面の上面縁が面取り
されて凹曲面を呈するとともに下面縁が面取りされて凸
曲面を呈し、対向する他側面と上面との間になす角度θ
2が10°であるものを使用した。凹曲面は、弧の長さが
上記線光源の円周の１／３で、その上端点Ａと下端点Ｂ
とを結ぶ弦ＡＢと導光板上面の延長線との間になす角度
θ１が50°であり、線光源と全面で密着するものであっ
た。導光板の下面には、散乱物質を含有したインキを用
いて、凹曲面より遠ざかるにつれてその面積率が大きく
なるドット状のグラデーションパターンで光拡散透過部
をスクリーン印刷にて設けた。以上のような導光板とそ
の凹曲面全面と密着するように配置された線光源とから
なる二個の面光源ユニットを、線光源側が両端となるよ
うに隣接させて面光源装置とした。このようにして得ら
れた面光源装置は、同じ線光源を用いた従来の面光源装
置に比べて高輝度の値が得られた。Embodiments of the surface light source device of the present invention will be described below.
A cold cathode ray tube with a diameter of 3.5 mm was used as a linear light source. The light guide plate is a transparent flat plate made of acrylic resin with a length of 220 mm, a width of 160 mm, and a thickness of 4 mm. One side surface of the transparent plate is chamfered to form a concave curved surface and the lower surface edge is chamfered to form a convex curved surface. Angle θ between the other side and the top
2 was 10 ° was used. The concave curved surface has an arc length of 1/3 of the circumference of the line light source, and the upper end point A and the lower end point B thereof.
The angle θ1 formed between the string AB connecting to and the extended line on the upper surface of the light guide plate was 50 °, and the surface was in close contact with the linear light source. On the lower surface of the light guide plate, an ink containing a scattering substance was used, and a light diffusion / transmission part was provided by screen printing in a dot-like gradation pattern whose area ratio increased as the distance from the concave curved surface increased. Two surface light source units composed of the above light guide plate and a linear light source arranged so as to be in close contact with the entire surface of the concave curved surface were adjacent to each other with both ends on the side of the linear light source to form a surface light source device. The surface light source device thus obtained has a higher brightness value than the conventional surface light source device using the same linear light source.
【００１９】[0019]
【発明の効果】本発明の面光源装置は、以上のような構
成および作用からなるので、次の効果が得られる。すな
わち、線光源から導光体内への光の入射が容易になり、
導光板内に入射した光のうち導光板の下面に対して垂直
に近い角度で入射した光が導光板の中央方向に全反射す
るので、線光源からの光を効率よく利用して、高輝度の
面光源を得ることができる。Since the surface light source device of the present invention has the above-described structure and operation, the following effects can be obtained. That is, it becomes easy for light to enter the light guide from the linear light source,
Of the light that has entered the light guide plate, the light that has entered the light guide plate at an angle that is nearly perpendicular to the bottom surface is totally reflected in the central direction of the light guide plate, so the light from the linear light source is used efficiently and high brightness is achieved. The surface light source can be obtained.
【図１】本発明に係る面光源装置の一実施例を示す部分
拡大断面図である。FIG. 1 is a partially enlarged sectional view showing an embodiment of a surface light source device according to the present invention.
【図２】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 2 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図３】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 3 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図４】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 4 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図５】従来品に係る面光源装置の一実施例を示す断面
図である。FIG. 5 is a cross-sectional view showing an example of a surface light source device according to a conventional product.
【図６】従来品に係る面光源装置の一実施例を示す断面
図である。FIG. 6 is a cross-sectional view showing an example of a surface light source device according to a conventional product.
１ 導光板 ２ 線光源 ３ ホルダ ４ 反射膜 ５ 拡散板 ６ 反射板 1 Light guide plate 2 Line light source 3 Holder 4 Reflective film 5 Diffuser plate 6 Reflector plate
【手続補正書】[Procedure amendment]
【提出日】平成６年２月３日[Submission date] February 3, 1994
【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】全文[Correction target item name] Full text
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【書類名】 明細書[Document name] Statement
【発明の名称】 面光源装置Title: Surface light source device
【特許請求の範囲】[Claims]
【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、液晶ディスプレイなど
に使用される薄型の面光源装置に関するものであり、と
くに高輝度の面光源の得られるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin surface light source device used in a liquid crystal display or the like, and particularly to a surface light source having high brightness.
【０００２】[0002]
【従来の技術】従来より、透明な導光板１の一側面に線
光源２を配置し、導光板１の下面に光拡散透過部を設け
た面光源装置があった（図５参照）。また、特開平２−
２７２４８６号公報には、下面に拡散透過部を有する導
光板１を拡散板５と反射板６との間に挟持し、導光板１
の上面を略Ｖ字状の凹面となして拡散板５への出射面と
なし、導光板１の少なくとも一方の端部側に線光源２を
配置し、線光源２に対応する導光板１の端面を線光源２
を部分的に取り囲む曲面となすと共に、この曲面と共に
線光源２を取り囲み反射膜４を内側に形成したホルダ３
を拡散板５に固定し、導光板１の曲面とホルダ３の反射
面とで線光源２を収容する部分を形成した面光源装置が
開示されている（図６参照）。2. Description of the Related Art Conventionally, there is a surface light source device in which a linear light source 2 is arranged on one side surface of a transparent light guide plate 1 and a light diffusion / transmission part is provided on the lower surface of the light guide plate 1 (see FIG. 5). In addition, JP-A-2-
In Japanese Patent No. 272486, a light guide plate 1 having a diffusion / transmission part on the lower surface is sandwiched between a diffusion plate 5 and a reflection plate 6, and
Of the light guide plate 1 corresponding to the line light source 2 is provided on at least one end side of the light guide plate 1 by forming a concave surface having a substantially V shape as an emission surface to the diffusion plate 5. Line source 2
And a curved surface that partially surrounds the linear light source 2 and the curved surface that surrounds the linear light source 2 and the reflective film 4 is formed inside.
Is fixed to the diffusion plate 5, and a surface light source device is disclosed in which the curved surface of the light guide plate 1 and the reflection surface of the holder 3 form a portion for housing the linear light source 2 (see FIG. 6).
【０００３】[0003]
【発明が解決しようとする課題】しかし、これらの面光
源装置では、導光板の側面と線光源との間に空気層が介
在して線光源から発した光の導光板内への入射量が制限
されるため、面発光の効率が悪く、輝度も低いという問
題があった。また、特開平２−２７２４８６号公報に開
示された面光源装置では、次の問題点もあった。すなわ
ち、特開平２−２７２４８６号公報に開示された面光源
装置では、導光板の両端面がＬ字型断面に形成されてお
り、そのコーナー部のみが略四半円形状の曲面を持つよ
うに形成されている。したがって、導光板内に入射した
光のうち導光板の下面に対して垂直に近い角度で入射し
た光が全反射を行わずに、そのまま導光板下面から出射
してしまうことになり、面発光の効率が悪く、輝度も低
いという問題があった。However, in these surface light source devices, there is an air layer between the side surface of the light guide plate and the line light source, and the amount of light emitted from the line light source entering the light guide plate is small. Because of the limitation, there are problems that the efficiency of surface emission is low and the brightness is low. Further, the surface light source device disclosed in JP-A-2-272486 has the following problems. That is, in the surface light source device disclosed in Japanese Patent Application Laid-Open No. 2-272486, both end surfaces of the light guide plate are formed in an L-shaped cross section, and only the corners thereof are formed so as to have a substantially quadrilateral curved surface. Has been done. Therefore, of the light that has entered the light guide plate, the light that has entered the light guide plate at an angle that is nearly perpendicular to the lower surface of the light guide plate is not totally reflected and is directly emitted from the lower surface of the light guide plate. There were problems of low efficiency and low brightness.
【０００４】したがって、本発明は、上記の問題点を解
決し、線光源からの光を効率よく利用して、高輝度の面
光源を得ることのできる面光源装置を提供することを目
的とする。Therefore, an object of the present invention is to solve the above problems and to provide a surface light source device capable of obtaining a high brightness surface light source by efficiently utilizing light from a linear light source. .
【０００５】[0005]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明の面光源装置は、下面に光拡散透過部の設
けられた透明な平板の一側面の上面縁が面取りされて凹
曲面を呈するとともに下面縁が面取りされて凸曲面を呈
する導光板と、導光板の凹曲面全面と密着するように配
置された線光源とからなる面光源ユニットを備え、導光
板の凹曲面の弧の長さが線光源の円周の１／４〜１／２
であり、凹曲面の上端点Ａと下端点Ｂとを結ぶ弦ＡＢと
導光板上面の延長線との間になす角度が３０〜６０°で
あるように構成した。In order to achieve the above object, the surface light source device of the present invention is such that one side surface of a transparent flat plate having a light diffusing and transmitting portion on its lower surface is chamfered to form a concave surface. The light guide plate having a curved surface and a convex curved surface with a chamfered lower edge, and a surface light source unit including a line light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate are provided. Is 1/4 to 1/2 of the circumference of the line light source
The angle between the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the extension line of the upper surface of the light guide plate is 30 to 60 °.
【０００６】また、本発明の面光源装置は、下面に光拡
散透過部の設けられた透明な平板の対向する二側面の上
面縁が面取りされて凹曲面を呈するとともに下面縁が面
取りされて凸曲面を呈する導光板と、導光板の凹曲面全
面と密着するようにそれぞれ配置された線光源とからな
る面光源ユニットを備え、導光板の凹曲面の弧の長さが
線光源の円周の１／４〜１／２であり、凹曲面の上端点
Ａと下端点Ｂとを結ぶ弦ＡＢと導光板上面の延長線との
間になす角度が３０〜６０°であるように構成すること
もできる。Further, in the surface light source device of the present invention, the upper surface edges of two opposing side surfaces of the transparent flat plate having the light diffusing and transmitting portion on the lower surface are chamfered to form a concave curved surface and the lower surface edges are chamfered to be convex. A surface light source unit including a light guide plate having a curved surface and a linear light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate is provided, and the arc length of the concave curved surface of the light guide plate is equal to the circumference of the linear light source. The angle is 1/4 to 1/2, and the angle formed between the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the extension line of the upper surface of the light guide plate is 30 to 60 °. You can also
【０００７】また、本発明の面光源装置は、下面に光拡
散透過部の設けられた透明な平板の一側面の上面縁が面
取りされて凹曲面を呈するとともに下面縁が面取りされ
て凸曲面を呈し且つ前記一側面に対向する他側面と上面
との間になす角度が５〜４５°である導光板と、導光板
の凹曲面全面と密着するように配置された線光源とから
なる二個の面光源ユニットが、線光源側が両端となるよ
うにして並設され、導光板の凹曲面の弧の長さが線光源
の円周の１／４〜１／２であり、凹曲面の上端点Ａと下
端点Ｂとを結ぶ弦ＡＢと導光板上面の延長線との間にな
す角度が３０〜６０°であるように構成することもでき
る。Further, in the surface light source device of the present invention, the upper surface edge of one side of the transparent flat plate having the light diffusing and transmitting portion on the lower surface is chamfered to form a concave curved surface, and the lower surface edge is chamfered to form a convex curved surface. Two of a light guide plate that is present and has an angle of 5 to 45 ° between the other side surface facing the one side surface and the upper surface, and a line light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate. Surface light source units are arranged side by side so that the linear light source side is at both ends, and the arc length of the concave curved surface of the light guide plate is 1/4 to 1/2 of the circumference of the linear light source. The angle between the chord AB connecting the end point A and the lower end point B and the extension line of the upper surface of the light guide plate may be 30 to 60 °.
【０００８】以下、本発明の面光源装置を図を用いてさ
らに詳しく説明する。Hereinafter, the surface light source device of the present invention will be described in more detail with reference to the drawings.
【０００９】図１は本発明の面光源装置の一実施例を示
す部分拡大断面図、図２は本発明の面光源装置の一実施
例を示す断面図、図３は本発明の面光源装置の一実施例
を示す断面図、図４は本発明の面光源装置の一実施例を
示す断面図である。１は導光板、２は線光源をそれぞれ
示す。FIG. 1 is a partially enlarged sectional view showing an embodiment of the surface light source device of the present invention, FIG. 2 is a sectional view showing an embodiment of the surface light source device of the present invention, and FIG. 3 is a surface light source device of the present invention. 4 is a sectional view showing an embodiment of the present invention, and FIG. 4 is a sectional view showing an embodiment of the surface light source device of the present invention. Reference numeral 1 is a light guide plate, and 2 is a linear light source.
【００１０】導光板１の形状は、透明な平板の一側面の
上面縁が面取りされて凹曲面を呈するとともに下面縁が
面取りされて凸曲面を呈するものを用いる（図２参
照）。導光板１の凹曲面は、線光源２の外形の一部と一
致させることにより、その全面を線光源２と密着させる
ことができる。また、透明な平板の対向する２側面に面
取りをしたものを用いることもできる（図３参照）。The shape of the light guide plate 1 is such that one side surface of the transparent flat plate is chamfered at the upper surface edge to form a concave curved surface and the lower surface edge is chamfered to form a convex curved surface (see FIG. 2). The concave curved surface of the light guide plate 1 can be brought into close contact with the linear light source 2 by matching a part of the outer shape of the linear light source 2. It is also possible to use a transparent flat plate having two opposite side surfaces chamfered (see FIG. 3).
【００１１】また、凹曲面の弧の長さは線光源の円周の
１／４〜１／２であり、凹曲面の上端点Ａと下端点Ｂと
を結ぶ弦ＡＢと導光板１上面の延長線との間になす角度
（以下θ１とする。）は３０〜６０°である（図１参
照）。弧の長さが１／２以上になると、弧の両端付近か
ら導光板１内に入射した光の角度が導光板１の上面や線
光源２側の側面に対して垂直に近くなるので、全反射を
行わずにそのまま導光板１の外に出射してしまう。ま
た、導光板１を加工することも難しくなる。一方、弧の
長さが１／４以下だと、線光板２と導光板１とが密着す
る面積が小さくなるので、入射する光の量が少なくなり
充分な輝度が得られない。また、角度θ１が６０°以上
になると、導光板１内に入射した光の一部が全反射を行
わずに直線的に奥に進むので、線光源２の配置された側
と反対側の側面から光が出射する光が増える。一方、角
度θ１が３０°以下になると、導光板１内に入射した光
の一部が全反射を行わずに直線的に下方に進むので、下
面から出射する光が増えてしまい効率が悪い。The arc length of the concave curved surface is 1/4 to 1/2 of the circumference of the linear light source, and the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the upper surface of the light guide plate 1 are formed. The angle formed with the extension line (hereinafter referred to as θ 1 ) is 30 to 60 ° (see FIG. 1). When the length of the arc becomes 1/2 or more, the angle of the light that has entered the light guide plate 1 from the vicinity of both ends of the arc becomes nearly perpendicular to the upper surface of the light guide plate 1 and the side surface on the side of the linear light source 2. The light is directly emitted from the light guide plate 1 without being reflected. Further, it becomes difficult to process the light guide plate 1. On the other hand, if the length of the arc is ¼ or less, the area where the linear light plate 2 and the light guide plate 1 are in close contact with each other becomes small, so that the amount of incident light becomes small and sufficient brightness cannot be obtained. Further, when the angle θ 1 is 60 ° or more, a part of the light that has entered the light guide plate 1 travels straight inward without being totally reflected, so that the light on the side opposite to the side on which the linear light source 2 is arranged is located. Light emitted from the side surface increases. On the other hand, when the angle θ 1 is 30 ° or less, a part of the light that has entered the light guide plate 1 proceeds straight downward without being totally reflected, so that the light emitted from the lower surface increases and the efficiency is poor. .
【００１２】また、上面および下面の縁が面取りされた
側面に対向する他側面を、上面との間に５〜４５°の角
度（以下θ２する。）をなすようにしてもよい。角度θ
２を５〜４５°とすることによって、この側面から光が
出射することを防ぐことができる。角度θ２は４５°以
上になると側面より光が出射してしまい、５°以下にな
ると導光板１を加工することが難しくなる。Further, the other side surface, which faces the chamfered side surface of the upper and lower surfaces, may form an angle (hereinafter referred to as θ 2 ) of 5 to 45 ° with the upper surface. Angle θ
By setting 2 to 5 to 45 °, it is possible to prevent light from being emitted from this side surface. When the angle θ 2 is 45 ° or more, light is emitted from the side surface, and when it is 5 ° or less, it becomes difficult to process the light guide plate 1.
【００１３】また、導光板１の厚さおよび材質は、用途
に応じて適宜選択して用いられる。たとえば、液晶表示
装置のバックライトに適用される導光板１の場合には、
厚さ３〜５ｍｍ程度のものがとくに好ましく、アクリル
樹脂、ポリカーボネート樹脂、ポリ塩化ビニル樹脂また
はガラスなどの材質からなるものを用いるとよい。The thickness and material of the light guide plate 1 are appropriately selected and used according to the application. For example, in the case of the light guide plate 1 applied to the backlight of a liquid crystal display device,
Those having a thickness of about 3 to 5 mm are particularly preferable, and those made of a material such as acrylic resin, polycarbonate resin, polyvinyl chloride resin, or glass may be used.
【００１４】線光源２としては、熱陰極線管や冷陰極線
管などの陰極線管が用いられ、直径はとくに２〜４ｍｍ
程度のものが好ましい。また、線光源２の導光板１と密
着していない残りの部分を覆うように反射シートを配置
して、その内面の鏡面により線光源２からの光を導光板
１側に反射して効率よく利用できるようにしてもよい。As the line light source 2, a cathode ray tube such as a hot cathode ray tube or a cold cathode ray tube is used, and its diameter is particularly 2 to 4 mm.
Something is preferable. Further, a reflection sheet is arranged so as to cover the remaining part of the linear light source 2 that is not in close contact with the light guide plate 1, and the light from the linear light source 2 is reflected to the light guide plate 1 side efficiently by the mirror surface of the inner surface thereof. You may make it available.
【００１５】導光板１の下面には、線光源２からの光を
均一に配分する目的で、グラデーションパターンの光拡
散透過部（図示せず）が形成される。光拡散透過部の面
積率の変化には、たとえば、線光源２より遠ざかるにつ
れて面積率が大きくなるようなものがある。また、導光
板１の線光源２側から特定位置までは線光源２より遠ざ
かるにつれて面積率が大きくなり、特定位置からは面積
率が一定となるようなものもある。また、グラデーショ
ンパターンには、ドット状パターンで形成されるものや
ストライプ状パターンで形成されるものがある。光拡散
透過部としては、散乱物質を含有するインキを用いて、
スクリーン印刷することにより設けることができる。A light diffusion / transmission part (not shown) having a gradation pattern is formed on the lower surface of the light guide plate 1 for the purpose of uniformly distributing the light from the linear light source 2. The change of the area ratio of the light diffusion / transmission part may be such that the area ratio increases as the distance from the linear light source 2 increases. In addition, there is a type in which the area ratio increases from the linear light source 2 side of the light guide plate 1 to the specific position as the distance from the linear light source 2 increases, and the area ratio becomes constant from the specific position. In addition, the gradation pattern may be a dot pattern or a stripe pattern. As the light diffusion / transmission part, an ink containing a scattering substance is used,
It can be provided by screen printing.
【００１６】以上のような導光板１と線光源２とからな
る面光源ユニットが本願発明の面光源装置に組み込まれ
る。なお、二灯タイプの面光源ユニットは一灯タイプに
比べると光源が１つ多いので高輝度が得られるが、一方
の線光源２から導光板１内に入射した光の中の一部が、
他方の線光源２が配置された側面より出射して光のロス
が生ずる。そこで前記した角度θ２が５〜４５°である
一灯タイプの面光源ユニットを二個一組として線光源２
側が両端となるように隣接させて面光源装置に組み込む
ことによって、より高輝度でしかも効率のよい面発光を
得ることができる（図４参照）。The surface light source unit including the light guide plate 1 and the linear light source 2 as described above is incorporated in the surface light source device of the present invention. The two-lamp type surface light source unit has more light sources than the one-lamp type, so that high brightness can be obtained. However, a part of the light incident on the light guide plate 1 from one of the linear light sources 2 is
Light is emitted from the side surface on which the other linear light source 2 is arranged, and light loss occurs. Therefore, the line light source 2 includes two single-lamp type surface light source units each having an angle θ 2 of 5 to 45 °.
By incorporating them in the surface light source device so that the sides are adjacent to each other, it is possible to obtain more efficient and more efficient surface emission (see FIG. 4).
【００１７】本願発明の面光源装置では、上記の面光源
ユニットの他に、導光板１の上面側に拡散板を配置して
もよいし、導光板１の下面に反射板を配置してもよい
（図示せず）。In the surface light source device of the present invention, in addition to the above surface light source unit, a diffusion plate may be arranged on the upper surface side of the light guide plate 1, or a reflection plate may be arranged on the lower surface of the light guide plate 1. Good (not shown).
【００１８】[0018]
【作用】本発明の面光源装置は、上記のように構成され
るので、次の作用が得られる。Since the surface light source device of the present invention is constructed as described above, the following effects can be obtained.
【００１９】すなわち、（１）線光源と凹曲面を呈する
導光板とが特定の位置関係で隙間なく密着して配置され
ているため、線光源から導光体内への光の入射が容易に
なる。（２）また、導光板の線光源が配置された側面の
下面縁が面取りされて凸曲面を呈するため、導光板内に
入射した光のうち導光板の下面に対して垂直に近い角度
で入射した光が導光板の中央方向に全反射する。That is, (1) since the linear light source and the light guide plate having a concave curved surface are arranged in close contact with each other in a specific positional relationship without any gap, it becomes easy for light to enter the light guide body from the linear light source. . (2) Since the lower edge of the side surface of the light guide plate on which the linear light source is arranged is chamfered to form a convex curved surface, the light entering the light guide plate is incident at an angle almost perpendicular to the lower surface of the light guide plate. The reflected light is totally reflected toward the center of the light guide plate.
【００２０】[0020]
【実施例】以下、本発明の面光源装置の実施例を示す。Embodiments of the surface light source device of the present invention will be described below.
【００２１】線光源として、直径３．５ｍｍの冷陰極線
管を使用した。A cold cathode ray tube having a diameter of 3.5 mm was used as a linear light source.
【００２２】導光板として、縦２２０ｍｍ、横１６０ｍ
ｍ、厚さ４ｍｍのアクリル樹脂からなる透明な平板で、
その一側面の上面縁が面取りされて凹曲面を呈するとと
もに下面縁が面取りされて凸曲面を呈し、対向する他側
面と上面との間になす角度θ２が１０°であるものを使
用した。凹曲面は、弧の長さが上記線光源の円周の１／
３で、その上端点Ａと下端点Ｂとを結ぶ弦ＡＢと導光板
上面の延長線との間になす角度θ１が５０°であり、線
光源と全面で密着するものであった。220 mm long and 160 m wide as a light guide plate
It is a transparent flat plate made of acrylic resin with a thickness of 4 mm
An upper surface edge of one side surface thereof was chamfered to form a concave curved surface, a lower surface edge thereof was chamfered to form a convex curved surface, and an angle θ 2 formed between the other side surface and the upper surface facing each other was 10 °. The concave curved surface has an arc length of 1 / the circumference of the line light source.
In Example 3, the angle θ 1 formed between the chord AB connecting the upper end point A and the lower end point B and the extension line of the upper surface of the light guide plate was 50 °, which was in close contact with the linear light source over the entire surface.
【００２３】導光板の下面には、散乱物質を含有したイ
ンキを用いて、凹曲面より遠ざかるにつれてその面積率
が大きくなるドット状のグラデーションパターンで光拡
散透過部をスクリーン印刷にて設けた。On the lower surface of the light guide plate, an ink containing a scattering substance was used, and a light diffusion / transmission portion was provided by screen printing in a dot-like gradation pattern whose area ratio increases with distance from the concave curved surface.
【００２４】以上のような導光板とその凹曲面全面と密
着するように配置された線光源とからなる二個の面光源
ユニットを、線光源側が両端となるように隣接させて面
光源装置とした。Two surface light source units composed of the light guide plate and the linear light source arranged so as to be in close contact with the entire surface of the concave curved surface are adjacent to each other so that the linear light source side is at both ends, and the surface light source device is provided. did.
【００２５】このようにして得られた面光源装置は、同
じ線光源を用いた従来の面光源装置に比べて高輝度の値
が得られた。The surface light source device thus obtained has a higher brightness value than the conventional surface light source device using the same line light source.
【００２６】[0026]
【発明の効果】本発明の面光源装置は、以上のような構
成および作用からなるので、次の効果が得られる。Since the surface light source device of the present invention has the above-described structure and operation, the following effects can be obtained.
【００２７】すなわち、線光源から導光体内への光の入
射が容易になり、導光板内に入射した光のうち導光板の
下面に対して垂直に近い角度で入射した光が導光板の中
央方向に全反射するので、線光源からの光を効率よく利
用して、高輝度の面光源を得ることができる。That is, it becomes easier for light to enter the light guide from the linear light source, and of the light that has entered the light guide plate, the light that has entered the light guide plate at an angle nearly perpendicular to the lower surface of the light guide plate is at the center of the light guide plate. Since the light is totally reflected in the direction, it is possible to efficiently use the light from the linear light source and obtain a surface light source with high brightness.
【図面の簡単な説明】[Brief description of drawings]
【図１】本発明に係る面光源装置の一実施例を示す部分
拡大断面図である。FIG. 1 is a partially enlarged sectional view showing an embodiment of a surface light source device according to the present invention.
【図２】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 2 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図３】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 3 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図４】本発明に係る面光源装置の一実施例を示す断面
図である。FIG. 4 is a sectional view showing an embodiment of a surface light source device according to the present invention.
【図５】従来品に係る面光源装置の一実施例を示す断面
図である。FIG. 5 is a cross-sectional view showing an example of a surface light source device according to a conventional product.
【図６】従来品に係る面光源装置の一実施例を示す断面
図である。FIG. 6 is a cross-sectional view showing an example of a surface light source device according to a conventional product.
【符号の説明】 １ 導光板 ２ 線光源 ３ ホルダ ４ 反射膜 ５ 拡散板 ６ 反射板[Explanation of reference numerals] 1 light guide plate 2 line light source 3 holder 4 reflection film 5 diffusion plate 6 reflection plate
Claims (3)
平板の一側面の上面縁が面取りされて凹曲面を呈すると
ともに下面縁が面取りされて凸曲面を呈する導光板と、
導光板の凹曲面全面と密着するように配置された線光源
とからなる面光源ユニットを備え、導光板の凹曲面の弧
の長さが線光源の円周の１／４〜１／２であり、凹曲面
の上端点Ａと下端点Ｂとを結ぶ弦ＡＢと導光板上面の延
長線との間になす角度が30〜60°であることを特徴とす
る面光源装置。1. A light guide plate in which a top surface edge of one side surface of a transparent flat plate having a light diffusing and transmitting portion on its bottom surface is chamfered to present a concave curved surface, and a bottom surface edge is chamfered to present a convex curved surface.
A surface light source unit including a linear light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate is provided, and the arc length of the concave curved surface of the light guide plate is 1/4 to 1/2 of the circumference of the linear light source. The surface light source device is characterized in that the angle between the chord AB connecting the upper end point A and the lower end point B of the concave curved surface and the extension line of the upper surface of the light guide plate is 30 to 60 °.
平板の対向する二側面の上面縁が面取りされて凹曲面を
呈するとともに下面縁が面取りされて凸曲面を呈する導
光板と、導光板の凹曲面全面と密着するようにそれぞれ
配置された線光源とからなる面光源ユニットを備え、導
光板の凹曲面の弧の長さが線光源の円周の１／４〜１／
２であり、凹曲面の上端点Ａと下端点Ｂとを結ぶ弦ＡＢ
と導光板上面の延長線との間になす角度が30〜60°であ
ることを特徴とする面光源装置。2. A light guide plate having a concave curved surface with chamfered upper surface edges of two opposing side surfaces of a transparent flat plate having a light diffusing and transmitting portion on the lower surface, and a light guide plate having a convex curved surface. A surface light source unit including a linear light source arranged so as to be in close contact with the entire concave curved surface of the light plate is provided, and the arc length of the concave curved surface of the light guide plate is 1/4 to 1 / the circumference of the linear light source.
2 and chord AB connecting the upper end point A and the lower end point B of the concave curved surface
The surface light source device is characterized in that an angle formed between the light guide plate and the extension line of the light guide plate is 30 to 60 °.
平板の一側面の上面縁が面取りされて凹曲面を呈すると
ともに下面縁が面取りされて凸曲面を呈し且つ前記一側
面に対向する他側面と上面との間になす角度が５〜45°
である導光板と、導光板の凹曲面全面と密着するように
配置された線光源とからなる二個の面光源ユニットが、
線光源側が両端となるようにして並設され、導光板の凹
曲面の弧の長さが線光源の円周の１／４〜１／２であ
り、凹曲面の上端点Ａと下端点Ｂとを結ぶ弦ＡＢと導光
板上面の延長線との間になす角度が30〜60°であること
を特徴とする面光源装置。3. A transparent flat plate having a light diffusing and transmitting portion on its lower surface is chamfered at one side surface to form a concave curved surface, and at the same time, a lower surface edge is chamfered to form a convex curved surface and faces the one side surface. The angle between the other side and the top is 5 to 45 °
, And two surface light source units consisting of a line light source arranged so as to be in close contact with the entire concave curved surface of the light guide plate,
The line light source side is arranged side by side so that the arc length of the concave curved surface of the light guide plate is 1/4 to 1/2 of the circumference of the line light source, and the upper end point A and the lower end point B of the concave curved surface are The surface light source device is characterized in that an angle formed between a string AB connecting with and an extension line of the upper surface of the light guide plate is 30 to 60 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5143060A JPH06331985A (en) | 1993-05-20 | 1993-05-20 | Surface light source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5143060A JPH06331985A (en) | 1993-05-20 | 1993-05-20 | Surface light source |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06331985A true JPH06331985A (en) | 1994-12-02 |
Family
ID=15329983
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5143060A Withdrawn JPH06331985A (en) | 1993-05-20 | 1993-05-20 | Surface light source |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06331985A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100508236B1 (en) * | 1998-04-27 | 2005-11-03 | 엘지.필립스 엘시디 주식회사 | Back light unit with side tilt |
-
1993
- 1993-05-20 JP JP5143060A patent/JPH06331985A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100508236B1 (en) * | 1998-04-27 | 2005-11-03 | 엘지.필립스 엘시디 주식회사 | Back light unit with side tilt |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20000801 |