JP3670639B2

JP3670639B2 - Light guide

Info

Publication number: JP3670639B2
Application number: JP2002318167A
Authority: JP
Inventors: カリルカランタル
Original assignee: 日本ライツ株式会社
Priority date: 2002-10-31
Filing date: 2002-10-31
Publication date: 2005-07-13
Anticipated expiration: 2022-10-31
Also published as: JP2004151511A

Description

【０００１】
【発明の属する技術分野】
本発明は、液晶表示装置を多数用いた大型のディスプレやマルチ画像ならびにＲＧＢのＬＥＤ光源等を利用した平面光源を用いた大型のディスプレやマルチ画像の各単位を構成する平面光源の各隣り合った部分の境目に設けられる導光体に関し、互いに隣り合う平面光源の縁からの出射光を導き、互いに隣り合う平面光源を跨いだ位置の１つの出射面から出射して各隣り合った部分の境目を目立たなくすることができる導光体に関する。
【０００２】
【従来の技術】
従来、液晶表示装置を多数、左右や上下またはマトリックス状につなぎ合わせた大型の液晶表示ディスプレやマルチ画像等は知られている。
【０００３】
また、液晶表示装置を多数用いた大型のディスプレやマルチ画像等の光源として平面光源を用いた場合には、平面光源自身の大きさに限界がある。このため、大型のディスプレやマルチ画像用に平面光源を左右や上下またはマトリックス状につなぎ合わせて大型の平面光源を構成したものが知られている。
【０００４】
さらに、赤色、緑色、青色（ＲＧＢ）の半導体発光素子等の光源をマトリックス状に配置した大型のディスプレやマルチ画像が知られている。
【０００５】
また、大型化平面光源として液晶表示装置等の裏面側に線状光源を複数並べて上方に出射する直下型平面照明装置も知られている。
【０００６】
【発明が解決しようとする課題】
従来の大型液晶表示ディスプレやマルチ画像等で、液晶表示装置を多数、左右や上下またはマトリックス状につなぎ合わせて大型化したものでは、個々の液晶表示装置のつなぎ目が目立ってしまう。このため、見栄えが悪く、常に格子越しから観たように格子状の線を見ないようにさせることができなかった。
【０００７】
また、液晶表示装置を多数用いた大型のディスプレやマルチ画像等の光源として平面光源を用いた場合には、平面光源自身の大きさに限界がある。このため、大型のディスプレやマルチ画像用に平面光源を左右や上下またはマトリックス状につなぎ合わせた大型の平面光源を採用している。しかし、この大型の平面光源では、平面光源をつなぎ合わせたつなぎ目の部分の輝度が異常に低く液晶表示の輝度に斑を発生させてしまう課題がある。また、最悪の場合には、平面光源のつなぎ目が格子状の暗線として現れてしまう課題がある。
【０００８】
さらに、赤色、緑色、青色（ＲＧＢ）の半導体発光素子等の光源をマトリックス状にした大型のディスプレやマルチ画像にした場合でも、個々の半導体発光素子等の光源のつなぎ目が目立ってしまう。このため、見栄えが悪く、常に格子越しから観たように格子状の線を見ないようにさせることができなかった。
【０００９】
また、従来の大型平面光源として液晶表示装置等の裏面側に線状光源を複数並べて上方に出射する直下型平面照明装置では、複数の線状光源が互いに隣に作用してしまう。このため、全体としての輝度分布や装置の大型化ならびに装置の重量等に課題がある。
【００１０】
この発明は、このような課題を解決するためなされたもので、その目的は液晶表示装置をマトリックス状に多数用いた大型液晶ディスプレやマルチ画像等やこれら液晶表示装置用に平面光源をつなぎ合わせた大型の平面光源および赤色、緑色、青色（ＲＧＢ）の半導体発光素子等の光源をマトリックス状にした大型のディスプレやマルチ画像に対して、これら大型化するため多数をつなぎ合わせたつなぎ目に、各液晶表示装置や平面光源および半導体発光素子等の光源からの隣り合った出射光を一度導光体の入射端面部に取り込み、各隣り合っている境目の位置に設けた出射面から出射して、つなぎ目を隠してつなぎ目の存在認識をなくすとともに見栄えを良くすることもできる導光体を提供することにある。
【００１１】
【課題を解決するための手段】
上記課題を解決するため請求項１に係る導光体は、細長い矩形状の平坦面をなす出射面と、出射面に対向した位置または出射面よりも外側に対向した位置に出射面よりも幅が狭く細長い矩形状を有する２つの入射端面部と、出射面の長辺と入射端面部の外側長辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い矩形状の平坦面をなす裏面部と、裏面部の長辺と入射端面部の内側長辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する２つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面の長辺と外側側面部または外側傾斜面部とが接続する部分または／および裏面部の長辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有することを特徴とする。
【００１２】
請求項１に係る導光体は、細長い矩形状の平坦面をなす出射面と、出射面に対向した位置または出射面よりも外側に対向した位置に出射面よりも幅が狭く細長い矩形状を有する２つの入射端面部と、出射面の長辺と入射端面部の外側長辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い矩形状の平坦面をなす裏面部と、裏面部の長辺と入射端面部の内側長辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する２つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面の長辺と外側側面部または外側傾斜面部とが接続する部分または／および裏面部の長辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有するので、互いに隣り合う平面光源の境目を目立たなくすることができる。
左右や上下に設けた平面光源や液晶表示装置の境目の存在をなくし見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。
導光体自身による境目を無くし導光体の存在認識が出来ないようにする。
【００１３】
また、請求項２に係る導光体は、十形状の平坦面をなす出射面と、出射面に対向した位置または出射面よりも外側に対向した位置にＬ形状を有する４つの入射端面部と、出射面の４分の１のＬ形状辺と入射端面部の外側Ｌ形状辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い十形状の平坦面をなす裏面部と、裏面部のＬ形状辺と入射端面部の内側Ｌ形状辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する４つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面Ｌ形状辺と外側側面部または外側傾斜面部とが接続する部分または／および入射端面部の内側Ｌ形状辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有することを特徴とする。
【００１４】
請求項２に係る導光体は、十形状の平坦面をなす出射面と、出射面に対向した位置または出射面よりも外側に対向した位置にＬ形状を有する４つの入射端面部と、出射面の４分の１のＬ形状辺と入射端面部の外側Ｌ形状辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い十形状の平坦面をなす裏面部と、裏面部のＬ形状辺と入射端面部の内側Ｌ形状辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する４つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面Ｌ形状辺と外側側面部または外側傾斜面部とが接続する部分または／および入射端面部の内側Ｌ形状辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有するので、互いに隣り合う平面光源の境目を目立たなくすることができる。
左右や上下にマトリックス状に設けた平面光源や液晶表示装置の境目の存在をなくし見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。
導光体自身による境目を無くし導光体の存在認識が出来ないようにする。
【００１５】
さらに、請求項３に係る導光体は、光偏向素子が、凸形状または／および凹形状の球および楕円球の一部ならびに三角錘、円錐、四角錐、三角柱、四角柱、円柱から成ることを特徴とする。
【００１６】
請求項３に係る導光体は、光偏向素子が、凸形状または／および凹形状の球および楕円球の一部ならびに三角錘、円錐、四角錐、三角柱、四角柱、円柱から成るので、出射面からの必要な出射光の方向、輝度等およびこれらの組合せ等を選択することが出来る。
【００２３】
【発明の実施の形態】
以下、本発明の実施の形態を添付図面に基づき説明する。
なお、本発明は、従来の大型マルチ画像面や大型液晶画像および大型平面光源では一般的な液晶画面や平面光源を上下、左右およびマトリックス状につないで大型化するために、これら液晶画面や平面光源をつなぎ合わせた、つなぎ目の部分が目立って見づらかったり、部分的な輝度の低下や斑の発生、線状や格子状の暗線の発生を解消するための導光体を提供することにある。
【００２４】
このため、本発明の導光体は、液晶画面や平面光源が互いに隣り合う縁部分からの出射光を取り込む複数（２つまたは４つ）の入射端面部と、この入射端面部から入射した光を出射する細長い矩形状や十形状の出射面と、この出射面の長辺または出射面の４分の１のＬ形状辺と入射端面部の外側長辺または外側Ｌ形状辺とに接続する外側側面部と、出射面よりも幅の狭い裏面部と、この裏面部の長辺またはＬ形状辺と入射端面部の長辺または内側Ｌ形状辺とが接続する内側側面部と、これら出射面と入射端面部と裏面部と外側側面部と内側側面部とが接続する２つまたは４つの端側面部とを有した構成となっている。
【００２５】
また、光を屈折または／および全反射する球および楕円球の一部ならびに三角錐、円錐、四角錐、三角柱、四角柱、円柱の何れかから成る光偏向素子を出射面、裏面部、外側側面部、内側側面部に設けている。
【００２６】
これにより、入射端面部から入射した光を出射面方向に導いて出射面から光を出射させ、個々の光源のつなぎ目の線状や格子状の線の目立ちをなくし、見栄え良く完全に１つの大型ディスプレやマルチ画像を得ることができ、しかも容易に自由な大きさの大型のディスプレやマルチ画像を再現することができる導光体を提供している。
【００２７】
図１（ａ）は本発明に係る導光体の概略構成を示す斜視図、図１（ｂ）は図１（ａ）の導光体を入射端面部側（裏側）から見た図、図２（ａ）は本発明に係る導光体の他の構成の概略を示す斜視図、図２（ｂ）は図２（ａ）の導光体を入射端面部側（裏側）から見た図、図３および図４は本発明に係る導光体の断面図であって、光の軌跡を説明するための図、図５乃至図７は本発明に係る導光体を液晶表示装置や平面光源等の表面に載置する場合の実際の使用例を示す概略図である。
【００２８】
図１（ａ），（ｂ）の導光体１（１Ａ）は、平坦面をなす細長い矩形状の出射面２と、出射面２に対向した位置または出射面２よりも外側に対向した位置に出射面２よりも幅が狭く細長い矩形状の平坦面をなす２つの入射端面部３（３ａ，３ｂ）と、出射面２の長辺と入射端面部３の外側長辺とが接続する矩形状の外側側面部４（または外側傾斜面部４）と、出射面２よりも幅が狭く出射面２の反対面に位置する矩形状の平坦面をなす裏面部５と、裏面部５の長辺と入射端面部３の内側長辺とが接続する矩形状の内側側面部６（または内側傾斜面部６）と、これら出射面２と入射端面部３と裏面部５と外側側面部４（または外側傾斜面部４）と内側側面部６（または内側傾斜面部６）とが接続する矩形状の２つの端側面部７とから構成されている。
【００２９】
図２（ａ），（ｂ）の導光体１（１Ｂ）は、平坦面をなす十形状の出射面２と、出射面２に対向した位置または出射面２よりも外側に対向した位置にＬ形状の平坦面をなす４つの入射端面部３と、出射面２の４分の１のＬ形状辺と入射端面部３の外側Ｌ形状辺３４とが接続する外側側面部４（または外側傾斜面部４）と、出射面２よりも幅が狭く出射面２の反対面に位置する十形状の平坦面をなす裏面部５と、裏面部５のＬ形状辺と入射端面部３の内側Ｌ形状辺３６とが接続するＬ形状の内側側面部６（または内側傾斜面部６）と、これら出射面２と入射端面部３と裏面部５と外側側面部４（または外側傾斜面部４）と内側側面部６（または内側傾斜面部６）とが接続する矩形状の４つの端側面部７とからなる。
【００３０】
なお、図１および図２の例では、外側側面部４および内側側面部６を傾斜面とする外側傾斜面部４および内側傾斜面部６として図示している。
【００３１】
導光体１（１Ａ，１Ｂ）は、屈折率が１．４〜１．７程度の透明なアクリル樹脂（ＰＭＭＡ）やポリカーボネート（ＰＣ）等で形成されている。
【００３２】
また、導光体１（１Ａ，１Ｂ）における出射面２および外側側面部４（または外側傾斜面部４）および内側側面部６（または内側傾斜面部６）には、光を屈折または／および全反射する光偏向素子８が設けられている。
【００３３】
尚、外側側面部４（または外側傾斜面部４）と内側側面部６（または内側傾斜面部６）は、導光体１（１Ａ，１Ｂ）の大きさや図示しない液晶表示装置や平面光源等の出射光によって図３に示すような外側側面部４や内側側面部６の真直な面または図４に示すような外側傾斜面部４や内側傾斜面部６の傾斜面にするものである。
【００３４】
上述した導光体１（１Ａ，１Ｂ）において、入射端面部３から入射した光は、０≦｜γ｜≦ｓｉｎ^-1（１／ｎ）の式を満たす屈折角γの範囲γ＝０°〜±４２°で導光体１（１Ａ，１Ｂ）内を進む。また、導光体１（１Ａ，１Ｂ）と空気層（屈折率ｎ＝１）との境界面では、ｓｉｎθ＝（１／ｎ）の式で臨界角α＝４２°となる。このため、入射角が臨界角よりも大きい場合には全反射し、臨界角を破らない限り導光体１（１Ａ，１Ｂ）内に閉じ込められ、導光体１（１Ａ，１Ｂ）内から脱出できない。
【００３５】
ここで、図３の導光体１（１Ａ，１Ｂ）の断面図に基づいて光の軌跡を説明する。
図３の例では、出射面２に対して直角な真直な面を有する外側側面部４や内側側面部６としている。図３において、入射端面部３から入射した光線は、屈折角γの範囲γ＝０°〜±４２°で導光体１（１Ａ，１Ｂ）内を進む。そして、真直ぐな光線Ｌ１は、屈折せずに真直ぐ進み、出射面２から直接出射光Ｌ０１として出射する。
【００３６】
また、入射端面部３（３ａ）で屈折した±４２°程度の光線Ｌｒは、外側側面部４や内側側面部６で全反射をしながら進み、さらに出射面２でも全反射を繰り返す。ここで、出射面２に設けた光偏向素子８に達した光線は、光偏向素子８（ここでは凸形状）によって屈折して出射面２から光線Ｌｒ１を出射する。
【００３７】
同様に、入射端面部３（３ｂ）で屈折した±４２°程度の光線Ｌｒは、外側側面部４や内側側面部６で全反射しながら進み、さらに出射面２でも全反射を繰り返す。ここで、裏面部５に設けた光偏向素子８に達した光線は、光偏向素子８（ここでは凹形状）によって全反射して裏面部５から出射面２方向に進み、出射面２から光線Ｌｒ２を出射する。
【００３８】
尚、光偏向素子８は、球および楕円球の一部ならびに三角錐、円錐、四角錐、三角柱、四角柱、円柱等の内から出射面２から最適な光が出射するように選択する。
【００３９】
例えば、出射面２に設けた光偏向素子８の位置が図３の導光体１の左寄りにある場合で、もっと導光体１（１Ａ，１Ｂ）の出射面２の中心方向に出射しなければならない時には、凸形状の球の一部の円弧状面よりも屈折する出射面と成る面の角度が小さい三角錐や四角錐を用いて出射面２に沿った出射光を得た方が良い。
【００４０】
このように、光偏向素子８は出射面２からの必要な出射光の方向、輝度等およびこれらの組み合わせ等を選択をし、導光体１（１Ａ，１Ｂ）の入射端面部３からの直進光による出射面２からの出射光と、全反射等で伝播した光を屈折させて偏向して導光体１の中央方向からの出射光とによって導光体１（１Ａ，１Ｂ）の出射面２全体から均一に出射することができる。
【００４１】
次に、図４の導光体１（１Ａ，１Ｂ）の断面図に基づいて光の軌跡を説明する。
図４の例では、出射面２に対して所定角度の傾斜面を有する外側傾斜面部４や内側傾斜面部６としている。図４において、入射端面部３から入射した光線は、屈折角γの範囲γ＝０°〜±４２°で導光体１（１Ａ，１Ｂ）内を進む。そして、真直ぐな光線Ｌ１は、外側傾斜面部４に進み、外側傾斜面部４で全反射を行い、さらに出射面２方向に進む。ここで、出射面２に設けた光偏向素子８に達した光線は、光偏向素子８（ここでは凸形状）によって屈折して出射面２から光線Ｌｍｒ１を出射する。
【００４２】
また、入射端面部３（３ａ，３ｂ）から入射して真直ぐに進んだ光線Ｌ１の内で、外側傾斜面部４に設けた光偏向素子８（ここでは凸形状）に進んだ光線Ｌ１は、光偏向素子８で屈折して外側傾斜面部４から光線Ｌ０ｍ１を出射する。
【００４３】
さらに、入射端面部３（３ｂ）で屈折した±４２°程度の光線Ｌｒは、外側傾斜面部４や内側傾斜面部６で全反射しながら進む。ここで、出射面２に達して出射面２に設けた光偏向素子８に達した光線は、光偏向素子８（ここでは凸形状）によって屈折して出射面２から光線Ｌｍｒ２を出射する。
【００４４】
なお、図示はしないが、図３でも説明したように、入射端面部３で屈折した±４２°程度の光線Ｌｒは、外側側面部４や内側側面部６で全反射をしながら進み、さらに出射面２でも全反射を繰り返す。ここで、裏面部５に設けた光偏向素子８に達した光線は、光偏向素子８によって全反射して裏面部５から出射面２方向に進み出射面２から光線を出射する。
なお、図４での光偏向素子８についての説明は、図３で説明した場合と同様に作用するので、ここでは省略する。
【００４５】
ところで、導光体１（１Ａ，１Ｂ）は、図１（ａ）や図２（ａ）に示すように、出射面２の長辺および出射面２のＬ形状辺と外側側面部４（または外側傾斜面部４）とが接続する部分または／および裏面部５の長辺および入射端面部３の内側Ｌ形状辺と内側側面部６（または内側傾斜面部６）とが接続する部分に所定曲率の丸みを有するようにしても良い。
【００４６】
また、導光体１（１Ａ，１Ｂ）は、出射面２の縁部分に所定曲率の丸みをもたせるのが好ましい。これにより、導光体１（１Ａ，１Ｂ）自身による出射面２と外側側面部４や外側傾斜面部４との境目を無くして入射端面部３から入射した光線による接続する稜線からの出射や外光による反射光による導光体１の存在認識が出来ないようにすることができる。
【００４７】
同様に、裏面部５の縁部分にも所定曲率の丸みをもたせるのが好ましい。これにより、導光体１自身による裏面部５と内側側面部６や内側傾斜面部６との境目を無くして入射端面部３から入射した光線による接続する谷線からの出射による反射光による導光体１（１Ａ，１Ｂ）の存在認識が出来ないようにすることができる。
【００４８】
図５は複数の平面光源１０や液晶表示装置１０を左右や上下に設けた平面光源１０や液晶表示装置１０の境目１２位置上に本発明の導光体１（１Ａ）を設けた略断面図である。
【００４９】
また、図６（ａ），（ｂ）は複数の平面光源１０や液晶表示装置１０を左右や上下またはマトリックス状に設けた平面光源１０や液晶表示装置１０の境目１２位置上に本発明の導光体１（１Ａ，１Ｂ）を設けた略平面図である。
【００５０】
図５や図６（ａ）に示すように、複数の平面光源１０や液晶表示装置１０を左右や上下に設けた場合には、図１に示す本発明の導光体１Ａを用いる。そして、隣り合う平面光源１０や液晶表示装置１０の境目１２（破線）の位置に互いの２つの平面光源１０や液晶表示装置１０を跨ぐ様に導光体１Ａを載置する。これにより、平面光源１０や液晶表示装置１０の縁から出射される光を導光体１Ａの入射端面部３から導光板１Ａ内に導き、導光体１Ａの存在が認識されないように導光体１Ａの出射面２から光を出射する。
【００５１】
すなわち、従来の大型液晶表示ディスプレやマルチ画像等の平面光源や液晶表示装置を多数、左右や上下につなぎ合わせて大型化したものでは、個々の平面光源や液晶表示装置のつなぎ目１２が目立ってしまい、見栄えが悪かった。しかも、平面光源をつなぎ合わせたつなぎ目１２の部分の輝度が異常に低く、液晶表示の輝度に斑を発生させたり、平面光源のつなぎ目１２に暗線として現われる。しかし、上述した図５や図６（ａ）の例のように、本例の導光板１Ａを採用することにより、上記問題を回避して、左右や上下に設けた平面光源や液晶表示装置の境目１２の存在をなくし、見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。
【００５２】
また、図６（ｂ）に示すように、複数の平面光源１０や液晶表示装置１０をマトリックス状に設けた場合には、図２に示す本発明の導光体１Ｂを用いる。そして、隣り合う平面光源１０や液晶表示装置１０の境目１２の位置に互いの４つの平面光源１０や液晶表示装置１０を跨ぐ様に導光体１Ｂを載置する。これにより、平面光源１０や液晶表示装置１０の縁から出射される光を導光体１の入射端面部３から導光体１Ｂ内に導き、導光体１Ｂの存在が認識されないように導光体１Ｂの出射面２から光を出射する。
【００５３】
さらに、図７に示すように、超大型の液晶表示ディスプレや、マルチ画像および平面光源等がマトリックス状につなぎ合わせて用いる場合には、２種類の導光体１Ａ，１Ｂを組み合わせて使用することで制限なく大型化することができる。例えば、網目状になるマトリックスの結合点には出射面２が十形状をした導光体１Ｂを載置し、これら導光体１Ｂの結合点間には、出射面２が直線状をした導光体１Ａを載置する。これにより、境目１２の存在をなくし見やすく見栄えの良い完全に１つの超大型表示装置を得ることができる。
【００５４】
すなわち、従来の大型液晶表示ディスプレやマルチ画像等の平面光源や液晶装置を多数、マトリックス状につなぎ合わせて大型化したものでは、個々の平面光源や液晶表示装置のつなぎ目１２が目立ってしまい、見栄えが悪かった。しかも、常に格子越しから観たように格子状の線１２を認識してしまい、平面光源をつなぎ合わせたつなぎ目１２の部分の輝度が異常に低く、液晶表示の輝度に斑を発生させたり、平面光源のつなぎ目１２が格子状１２の暗線として現われる。しかし、上述した図６（ｂ）や図７の例のように、本例の導光体１Ａ，１Ｂを採用することにより、上記問題を回避して、マトリックス状に設けた平面光源や液晶表示装置の境目１２の存在をなくし、見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。
【００５５】
また、これら平面光源や液晶表示装置だけでなく、赤色、緑色、青色（ＲＧＢ）の半導体発光素子等の光源（例えば、半導体発光素子を矩形形状のパッケージにして、矩形形状の開口部から出射する。）をマトリックス状にした大型のディスプレやマルチ画像にした場合でも、個々の光源のつなぎ目が目立ってしまい、見栄えが悪く、常に格子越しから観たような格子状の線を認識してしまう。しかし、本例の導光体１を採用することにより、マトリックス状に設けた光源の境目の存在をなくし、見やすく見栄えの良い完全に１つの大型のディスプレやマルチ画像を得ることができる。
【００５６】
このように、従来、複数の平面光源や液晶表示装置等を上下、左右およびマトリックス状に用いて大型した場合、平面光源や液晶表示装置等を互いにつなぎ合わせるために、つなぎ目が目立ってしまったり、輝度の斑が目立ってしまうという問題があった。
【００５７】
そこで、本発明では、各平面光源や液晶表示装置等のつなぎ目の位置に平面光源や液晶表示装置等を跨ぐように導光体を配置する。これにより、平面光源や液晶表示装置等の縁に対応した導光体の２つまたは４つの入射端面部から平面光源や液晶表示装置等からの出射光を導き、これら入射端面部に対向し、各平面光源や液晶表示装置等のつなぎ目の位置に１つの出射部から導光体内に導いた光を出射する。その結果、個々の光源のつなぎ目の線状や格子状の線の目立ちをなくし、見栄え良く完全に１つの大型のディスプレやマルチ画像を得ることができる。しかも、容易に自由な大きさの大型のディスプレやマルチ画像を再現することができる。
【００５８】
【発明の効果】
以上のように、請求項１に係る導光体は、細長い矩形状の出射面と、出射面に対向した位置または出射面よりも外側に対向した位置に出射面よりも幅が狭く細長い矩形状を有する２つの入射端面部と、出射面の長辺と入射端面部の外側長辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い矩形状の平坦面をなす裏面部と、裏面部の長辺と入射端面部の内側長辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する２つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面の長辺と外側側面部または外側傾斜面部とが接続する部分または／および裏面部の長辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有するので、互いに隣り合う平面光源の境目を目立たなくすることができる。これにより、見やすく見栄えの良い大型画面やマルチ画像面を得ることができる。
また、左右や上下に設けた平面光源や液晶表示装置の境目の存在をなくし見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。しかも、平面光源や液晶表示装置の数にとらわれずに大型化が容易にすることができるように自由に設計することができる。
さらに、導光体自身による境目を無くし導光体の存在認識が出来ないようにする。このため、導光体の異物感が無く平面光源や液晶表示装置からの出射光と導光体からの出射光が、完全に一体化することができる。
【００５９】
また、請求項２に係る導光体は、十形状の平坦面をなす出射面と、出射面に対向した位置または出射面よりも外側に対向した位置にＬ形状を有する４つの入射端面部と、出射面の４分の１のＬ形状辺と入射端面部の外側Ｌ形状辺とが接続する外側側面部または外側傾斜面部と、出射面よりも幅の狭い十形状の平坦面をなす裏面部と、裏面部のＬ形状辺と入射端面部の内側Ｌ形状辺とが接続する内側側面部または内側傾斜面部と、これら出射面と入射端面部と裏面部と外側側面部または外側傾斜面部と内側側面部または内側傾斜面部とが接続する４つの端側面部とからなり、
出射面および裏面部および外側側面部または外側傾斜面部および内側側面部または内側傾斜面部には、光を屈折または／および全反射する光偏向素子を設け、
さらに出射面Ｌ形状辺と外側側面部または外側傾斜面部とが接続する部分または／および入射端面部の内側Ｌ形状辺と内側側面部または内側傾斜面部とが接続する部分は、丸みを有するので、互いに隣り合う平面光源の境目を目立たなくすることができる。これにより、見やすく見栄えの良い大型画面やマルチ画像面を得ることができる。
また、左右や上下にマトリックス状に設けた平面光源や液晶表示装置の境目の存在をなくし見やすく見栄えの良い完全に１つの大型表示装置を得ることができる。しかも、平面光源や液晶表示装置の数にとらわれずに大型化が容易にすることができるように自由に設計することができる。
さらに、導光体自身による境目を無くし導光体の存在認識が出来ないようにする。このため、導光体の異物感が無く平面光源や液晶表示装置からの出射光と導光体からの出射光が、完全に一体化することができる。
【００６０】
さらに、請求項３に係る導光体は、光偏向素子が、凸形状または／および凹形状の球および楕円球の一部ならびに三角錘、円錐、四角錐、三角柱、四角柱、円柱から成るので、出射面からの必要な出射光の方向、輝度等およびこれらの組合せ等を選択することが出来る。このため、導光体の入射端面部からの直進光による出射面からの出射光と全反射等で伝播した光を屈折させて偏向し、平面光源や液晶表示装置等の境目に対向した位置にある出射面からの出射光とが均一に出射することができる。
【図面の簡単な説明】
【図１】（ａ）本発明に係る導光体の概略構成を示す斜視図
（ｂ）（ａ）の導光体を入射端面部側（裏側）から見た図
【図２】（ａ）本発明に係る導光体の他の構成による概略を示す斜視図
（ｂ）（ａ）の導光体を入射端面部側（裏側）から見た図
【図３】本発明に係る導光体の断面図
【図４】本発明に係る導光体の他の例の断面図
【図５】本発明に係る導光体の実施断面図
【図６】本発明に係る導光体の他の実施略平面図
【図７】本発明に係る導光体の他の実施略平面図
【符号の説明】
１（１Ａ，１Ｂ）…導光体、２…出射面、３（３ａ，３ｂ）…入射端面部、４…外側側面部，外側傾斜面部、５…裏面部、６…内側側面部，内側傾斜面部、７…端側面部、８…光偏向素子、１０…液晶表示装置または平面光源、１２…つなぎ目，境目，格子状、３４…外側Ｌ形状辺、３６…内側Ｌ形状辺、Ｌ１，Ｌ０１，Ｌｒ，Ｌｒ１，Ｌｒ２，Ｌ０ｍ１，Ｌｍｒ１，Ｌｍｒ２…光線。[0001]
BACKGROUND OF THE INVENTION
The present invention is such that a large display using a large number of liquid crystal display devices and a multi-image, and a large-sized display using a planar light source using an RGB LED light source, etc. With respect to the light guide provided at the boundary between the portions, the light emitted from the edges of the adjacent planar light sources is guided and emitted from one emitting surface at a position straddling the adjacent planar light sources, and the boundary between the adjacent portions It is related with the light guide which can make it inconspicuous.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, large-sized liquid crystal display displays, multi-images, and the like in which a large number of liquid crystal display devices are connected in the left, right, up, down, or matrix form are known.
[0003]
Further, when a flat light source is used as a light source for a large display or a multi-image using a large number of liquid crystal display devices, the size of the flat light source itself is limited. For this reason, there is known a large planar light source configured by connecting planar light sources to the left, right, up, down, or in a matrix for a large display or multi-image.
[0004]
Furthermore, large displays and multi-images in which light sources such as red, green and blue (RGB) semiconductor light emitting elements are arranged in a matrix are known.
[0005]
In addition, a direct-type planar illumination device that emits a plurality of linear light sources on the back side of a liquid crystal display device or the like as a large planar light source is also known.
[0006]
[Problems to be solved by the invention]
In a conventional large-sized liquid crystal display, multi-images, etc., in which a large number of liquid crystal display devices are joined together in the left, right, top, bottom, or matrix form, the joints between the individual liquid crystal display devices become conspicuous. For this reason, it did not look good, and it was not always possible to hide the grid-like lines as seen from the grid.
[0007]
Further, when a flat light source is used as a light source for a large display or a multi-image using a large number of liquid crystal display devices, the size of the flat light source itself is limited. For this reason, a large planar light source in which planar light sources are connected to the left, right, top, bottom, or matrix is used for large displays and multi-images. However, in this large planar light source, there is a problem that the luminance of the joint portion where the planar light sources are joined is abnormally low, causing unevenness in the luminance of the liquid crystal display. In the worst case, there is a problem that the joint of the planar light source appears as a grid-like dark line.
[0008]
Furthermore, even when the light source such as red, green, and blue (RGB) semiconductor light emitting elements is made into a large display or multi-image in a matrix shape, the connection of the light sources such as individual semiconductor light emitting elements becomes conspicuous. For this reason, it did not look good, and it was not always possible to hide the grid-like lines as seen from the grid.
[0009]
Further, in a direct type planar illumination device that emits a plurality of linear light sources on the back side of a liquid crystal display device or the like as a conventional large planar light source, the plurality of linear light sources act next to each other. For this reason, there are problems in the luminance distribution as a whole, the enlargement of the apparatus, the weight of the apparatus, and the like.
[0010]
The present invention has been made to solve such a problem, and its purpose is to connect a large-sized liquid crystal display or a multi-image using a large number of liquid crystal display devices in a matrix, or a planar light source for these liquid crystal display devices. For large displays and multi-images in which large planar light sources and light sources such as red, green and blue (RGB) semiconductor light emitting elements are arranged in a matrix, each liquid crystal is connected to a joint where many are connected to increase the size. Adjacent outgoing light from a light source such as a display device, a flat light source, and a semiconductor light emitting element is once taken into the incident end face portion of the light guide, and emitted from the outgoing surface provided at the position of each adjacent boundary. It is to provide a light guide body that can hide the joint and eliminate the presence of the joint and improve the appearance.
[0011]
[Means for Solving the Problems]
 In order to solve the above problem, a light guide according to claim 1 is provided.An outgoing surface forming an elongated rectangular flat surface, two incident end face portions having an elongated rectangular shape narrower than the outgoing surface at a position facing the outgoing surface or a position facing the outer side of the outgoing surface, and an outgoing surface The outer side and the outer inclined side of the incident end surface, the back surface forming a rectangular flat surface narrower than the exit surface, the long side of the back surface and the incident end surface The inner side surface or inner inclined surface portion to which the inner long side of the portion is connected, and the two exit surfaces, the incident end surface portion, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion are connected. It consists of an end side part,
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Further, the portion where the long side of the emission surface is connected to the outer side surface portion or the outer inclined surface portion or / and the portion where the long side of the back surface portion is connected to the inner side surface portion or the inner inclined surface portion are rounded.It is characterized by that.
[0012]
 The light guide according to claim 1 is:An outgoing surface forming an elongated rectangular flat surface, two incident end face portions having an elongated rectangular shape narrower than the outgoing surface at a position facing the outgoing surface or a position facing the outer side of the outgoing surface, and an outgoing surface The outer side and the outer inclined side of the incident end surface, the back surface forming a rectangular flat surface narrower than the exit surface, the long side of the back surface and the incident end surface The inner side surface or inner inclined surface portion to which the inner long side of the portion is connected, and the two exit surfaces, the incident end surface portion, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion are connected. It consists of an end side part,
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Further, the portion where the long side of the emission surface is connected to the outer side surface portion or the outer inclined surface portion or / and the portion where the long side of the back surface portion is connected to the inner side surface portion or the inner inclined surface portion are rounded.Therefore, the boundary between the planar light sources adjacent to each other can be made inconspicuous.
 It is possible to obtain a completely large display device that is easy to see and has a good appearance by eliminating the presence of the boundary between the planar light source and the liquid crystal display device provided on the left and right and the top and bottom.
 The boundary between the light guide itself is eliminated so that the existence of the light guide cannot be recognized.
[0013]
 Moreover, the light guide according to claim 2 is:A ten-shaped flat surface, four incident end surfaces having an L shape at a position facing the light emitting surface or a position facing outside the light emitting surface, and a quarter of the L-shaped side of the light emitting surface An outer side surface portion or an outer inclined surface portion that connects the outer L-shaped side of the incident end surface portion, a rear surface portion that forms a ten-shaped flat surface that is narrower than the exit surface, and an L-shaped side and incident end surface portion of the rear surface portion The inner side surface portion or the inner inclined surface portion to which the inner L-shaped side of each other is connected, the emission surface, the incident end surface portion, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion are connected. It consists of an end side part,
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Further, a portion where the exit surface L-shaped side and the outer side surface portion or the outer inclined surface portion are connected or / and a portion where the inner L-shaped side of the incident end surface portion and the inner side surface portion or the inner inclined surface portion are connected have roundness.It is characterized by that.
[0014]
 The light guide according to claim 2 is:A ten-shaped flat surface, four incident end surfaces having an L shape at a position facing the light emitting surface or a position facing outside the light emitting surface, and a quarter of the L-shaped side of the light emitting surface An outer side surface portion or an outer inclined surface portion that connects the outer L-shaped side of the incident end surface portion, a rear surface portion that forms a ten-shaped flat surface that is narrower than the exit surface, and an L-shaped side and incident end surface portion of the rear surface portion The inner side surface portion or the inner inclined surface portion to which the inner L-shaped side of each other is connected, the emission surface, the incident end surface portion, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion are connected. It consists of an end side part,
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Further, a portion where the exit surface L-shaped side and the outer side surface portion or the outer inclined surface portion are connected or / and a portion where the inner L-shaped side of the incident end surface portion and the inner side surface portion or the inner inclined surface portion are connected have roundness.Therefore, the boundary between the planar light sources adjacent to each other can be made inconspicuous.
 It is possible to obtain a completely large display device that is easy to see and has a good appearance by eliminating the boundary between the flat light source and the liquid crystal display device provided in a matrix form on the left and right and top and bottom.
 The boundary between the light guide itself is eliminated so that the existence of the light guide cannot be recognized.
[0015]
 Furthermore, the light guide according to claim 3 is:The light deflecting element is composed of a convex or / and concave concave sphere and a part of an elliptical sphere, a triangular pyramid, a cone, a quadrangular pyramid, a triangular prism, a quadrangular prism, and a cylinder.It is characterized by that.
[0016]
 The light guide according to claim 3 is:The light deflecting element is composed of a convex or / and concave concave sphere and a part of an elliptical sphere, a triangular pyramid, a cone, a quadrangular pyramid, a triangular prism, a quadrangular prism, and a cylinder.SoIt is possible to select a necessary direction of emitted light from the emission surface, luminance, a combination thereof, and the like.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
In the present invention, the conventional large multi-image surface, large liquid crystal image, and large flat light source are connected to a common liquid crystal screen or flat light source in the form of a vertical, left, right, and matrix to increase the size. It is an object of the present invention to provide a light guide body for eliminating a conspicuous portion of a joint where light sources are joined together, a partial decrease in luminance, generation of spots, and generation of linear and grid-like dark lines.
[0024]
For this reason, the light guide of the present invention includes a plurality of (two or four) incident end face portions that take in emitted light from adjacent edge portions of a liquid crystal screen or a flat light source, and light incident from the incident end face portions. An elongated rectangular or ten-shaped exit surface that emits light, an outer side connected to the long side of the exit surface or an L-shaped side that is a quarter of the exit surface, and the outer long side or the outer L-shaped side of the incident end surface portion A side surface, a back surface narrower than the exit surface, an inner side surface connecting the long side or L-shaped side of the back surface and the long side or inside L-shaped side of the incident end surface, and the exit surface; It has a configuration having two or four end side surfaces to which the incident end surface portion, the back surface portion, the outer side surface portion, and the inner side surface portion are connected.
[0025]
Further, a part of a sphere that refracts or / and totally reflects light and a part of an elliptical sphere, and a light deflecting element composed of any one of a triangular pyramid, a cone, a quadrangular pyramid, a triangular prism, a quadrangular prism, and a cylinder are used as an emission surface, a back surface portion, an outer side surface And the inner side surface.
[0026]
As a result, the light incident from the incident end face portion is guided in the direction of the exit surface, and the light is emitted from the exit surface, thereby eliminating the conspicuous lines and grid lines of each light source. There is provided a light guide that can obtain a display and a multi-image and can easily reproduce a large-sized display and a multi-image having a free size.
[0027]
1A is a perspective view showing a schematic configuration of a light guide according to the present invention, FIG. 1B is a view of the light guide of FIG. 1A viewed from the incident end face side (back side), and FIG. 2 (a) is a perspective view schematically showing another configuration of the light guide according to the present invention, and FIG. 2 (b) is a view of the light guide shown in FIG. 2 (a) as viewed from the incident end face side (back side). 3 and 4 are sectional views of the light guide according to the present invention, and are diagrams for explaining the trajectory of light. FIGS. 5 to 7 illustrate the light guide according to the present invention as a liquid crystal display device or a plane. It is the schematic which shows the actual usage example in the case of mounting on surfaces, such as a light source.
[0028]
 A light guide 1 (1A) in FIGS. 1A and 1B has a flat and elongated rectangular emission surface 2, and a position facing the emission surface 2 or a position facing the outside of the emission surface 2. The two incident end face portions 3 (3a, 3b) forming a rectangular flat surface that is narrower and narrower than the exit surface 2 are connected to the long side of the exit surface 2 and the outer long side of the entrance end face portion 3. The outer side surface portion 4 (or the outer inclined surface portion 4) having a shape and a rectangular shape which is narrower than the emission surface 2 and located on the opposite surface of the emission surface 2Make a flat surfaceThe back surface 5, the rectangular inner side surface 6 (or the inner inclined surface 6) that connects the long side of the back 5 and the inner long side of the incident end surface 3, the exit surface 2, and the incident end surface 3 The back surface portion 5, the outer side surface portion 4 (or the outer inclined surface portion 4), and the inner side surface portion 6 (or the inner inclined surface portion 6) are connected to each other and two rectangular end side surface portions 7.
[0029]
2 (a) and 2 (b), the light guide 1 (1B) has a flat-shaped ten-shaped emission surface 2 and a position facing the emission surface 2 or a position facing the outside of the emission surface 2. The outer side surface portion 4 (or the outer inclined surface) where the four incident end surface portions 3 forming an L-shaped flat surface, the quarter L-shaped side of the output surface 2 and the outer L-shaped side 34 of the incident end surface portion 3 are connected. The surface portion 4) and a tens shape which is narrower than the exit surface 2 and located on the opposite surface of the exit surface 2Make a flat surfaceThe back surface 5, the L-shaped inner side surface portion 6 (or the inner inclined surface portion 6) where the L-shaped side of the back surface portion 5 and the inner L-shaped side 36 of the incident end surface portion 3 are connected, and the exit surface 2 and the incident end surface It consists of four end side surface portions 7 having a rectangular shape to which the portion 3, the back surface portion 5, the outer side surface portion 4 (or the outer inclined surface portion 4) and the inner side surface portion 6 (or the inner inclined surface portion 6) are connected.
[0030]
In the example of FIGS. 1 and 2, the outer side surface portion 4 and the inner side surface portion 6 are illustrated as the outer inclined surface portion 4 and the inner inclined surface portion 6 which are inclined surfaces.
[0031]
The light guide 1 (1A, 1B) is formed of transparent acrylic resin (PMMA), polycarbonate (PC), or the like having a refractive index of about 1.4 to 1.7.
[0032]
Further, light is refracted or / and totally reflected by the light exit surface 2, the outer side surface portion 4 (or the outer inclined surface portion 4), and the inner side surface portion 6 (or the inner inclined surface portion 6) of the light guide 1 (1A, 1B). An optical deflection element 8 is provided.
[0033]
The outer side surface portion 4 (or the outer inclined surface portion 4) and the inner side surface portion 6 (or the inner inclined surface portion 6) have a size of the light guide 1 (1A, 1B), a liquid crystal display device (not shown), a flat light source, or the like. The straight surface of the outer side surface portion 4 and the inner side surface portion 6 as shown in FIG. 3 or the inclined surface of the outer inclined surface portion 4 and the inner inclined surface portion 6 as shown in FIG.
[0034]
In the light guide 1 (1A, 1B) described above, the light incident from the incident end face 3 is 0 ≦ | γ | ≦ sin.^-1The light guide 1 (1A, 1B) travels within a range γ = 0 ° to ± 42 ° of the refraction angle γ satisfying the expression (1 / n). Further, at the boundary surface between the light guide 1 (1A, 1B) and the air layer (refractive index n = 1), the critical angle α = 42 ° in the equation of sin θ = (1 / n). For this reason, when the incident angle is larger than the critical angle, the light is totally reflected, is confined in the light guide 1 (1A, 1B) unless it breaks the critical angle, and escapes from the light guide 1 (1A, 1B). Can not.
[0035]
Here, the locus of light will be described based on the cross-sectional view of the light guide 1 (1A, 1B) in FIG.
In the example of FIG. 3, the outer side surface portion 4 and the inner side surface portion 6 have straight surfaces perpendicular to the emission surface 2. In FIG. 3, the light beam incident from the incident end face part 3 travels in the light guide 1 (1A, 1B) in the range γ = 0 ° to ± 42 ° of the refraction angle γ. The straight light beam L1 travels straight without being refracted, and is emitted directly from the emission surface 2 as emitted light L01.
[0036]
Further, the light beam Lr of about ± 42 ° refracted at the incident end surface portion 3 (3a) travels while being totally reflected at the outer side surface portion 4 and the inner side surface portion 6, and further repeats total reflection at the exit surface 2. Here, the light beam that has reached the light deflection element 8 provided on the emission surface 2 is refracted by the light deflection element 8 (in this case, a convex shape) and is emitted from the emission surface 2 as a light beam Lr1.
[0037]
Similarly, a light ray Lr of about ± 42 ° refracted at the incident end surface portion 3 (3b) travels while being totally reflected by the outer side surface portion 4 and the inner side surface portion 6, and further repeats total reflection at the exit surface 2. Here, the light beam that has reached the light deflection element 8 provided on the back surface part 5 is totally reflected by the light deflection element 8 (here, concave shape) and travels from the back surface part 5 in the direction of the exit surface 2, and the light beam from the exit surface 2. Lr2 is emitted.
[0038]
The light deflection element 8 is selected so that optimum light is emitted from the emission surface 2 from a part of a sphere and an elliptical sphere, a triangular pyramid, a cone, a quadrangular pyramid, a triangular prism, a quadrangular prism, and a cylinder.
[0039]
For example, in the case where the position of the light deflection element 8 provided on the emission surface 2 is on the left side of the light guide 1 in FIG. 3, the light should be emitted more toward the center of the emission surface 2 of the light guide 1 (1A, 1B). When it is necessary, it is better to obtain outgoing light along the outgoing surface 2 using a triangular pyramid or a quadrangular pyramid with a smaller angle of the surface to be refracted than a part of the arcuate surface of the convex sphere. .
[0040]
In this way, the light deflection element 8 selects the necessary direction of emitted light from the exit surface 2, the brightness, etc., and combinations thereof, and goes straight from the entrance end face 3 of the light guide 1 (1 A, 1 B). The exit surface of the light guide 1 (1A, 1B) by the light exiting from the exit surface 2 and the light emitted from the central direction of the light guide 1 by refracting and deflecting the light propagated by total reflection or the like. 2 can be emitted uniformly from the whole.
[0041]
Next, the locus of light will be described based on the cross-sectional view of the light guide 1 (1A, 1B) in FIG.
In the example of FIG. 4, the outer inclined surface portion 4 and the inner inclined surface portion 6 each having an inclined surface with a predetermined angle with respect to the emission surface 2 are used. In FIG. 4, the light beam incident from the incident end face part 3 travels in the light guide 1 (1 A, 1 B) in the refraction angle γ range γ = 0 ° to ± 42 °. Then, the straight light ray L1 proceeds to the outer inclined surface portion 4, performs total reflection at the outer inclined surface portion 4, and further proceeds in the direction of the exit surface 2. Here, the light beam reaching the light deflection element 8 provided on the emission surface 2 is refracted by the light deflection element 8 (in this case, a convex shape) and is emitted from the emission surface 2 as a light beam Lmr1.
[0042]
In addition, among the light rays L1 that have entered from the incident end surface portion 3 (3a, 3b) and proceed straight, the light beam L1 that has traveled to the light deflection element 8 (here, convex shape) provided on the outer inclined surface portion 4 The light beam L0m1 is refracted by the deflecting element 8 and emitted from the outer inclined surface portion 4.
[0043]
Further, the light ray Lr of about ± 42 ° refracted by the incident end face part 3 (3b) travels while being totally reflected by the outer inclined face part 4 and the inner inclined face part 6. Here, the light beam reaching the light exit surface 2 and reaching the light deflection element 8 provided on the light exit surface 2 is refracted by the light deflection element 8 (in this case, a convex shape) and is emitted from the light exit surface 2 as a light beam Lmr2.
[0044]
Although not shown, as described with reference to FIG. 3, the light beam Lr refracted by the incident end surface portion 3 travels while being totally reflected by the outer side surface portion 4 and the inner side surface portion 6 and is further emitted. Surface 2 also repeats total reflection. Here, the light beam that has reached the light deflection element 8 provided on the back surface part 5 is totally reflected by the light deflection element 8, travels from the back surface part 5 in the direction of the emission surface 2, and is emitted from the emission surface 2.
Note that the description of the light deflection element 8 in FIG. 4 operates in the same manner as in the case described with reference to FIG.
[0045]
By the way, as shown in FIG. 1A and FIG. 2A, the light guide 1 (1A, 1B) includes the long side of the emission surface 2 and the L-shaped side of the emission surface 2 and the outer side surface portion 4 (or A portion having a predetermined curvature is connected to a portion where the outer inclined surface portion 4) is connected or / and a portion where the long side of the back surface portion 5 and the inner L-shaped side of the incident end surface portion 3 are connected to the inner side surface portion 6 (or the inner inclined surface portion 6). You may make it have roundness.
[0046]
Moreover, it is preferable that the light guide 1 (1A, 1B) has a predetermined curvature rounded on the edge portion of the emission surface 2. As a result, the light guide 1 (1A, 1B) itself emits light from the connecting ridge line by the light incident from the incident end face 3 without any boundary between the outgoing face 2 and the outer side face 4 or the outer inclined face 4 or outside. It is possible to prevent the presence of the light guide 1 from being reflected by reflected light.
[0047]
Similarly, it is preferable that the edge portion of the back surface portion 5 is rounded with a predetermined curvature. Thereby, the light guide 1 itself eliminates the boundary between the back surface portion 5 and the inner side surface portion 6 or the inner inclined surface portion 6, and is guided by the reflected light emitted from the connecting valley line by the light incident from the incident end surface portion 3. It is possible to prevent the body 1 (1A, 1B) from being recognized.
[0048]
FIG. 5 is a schematic cross-sectional view in which the light guide 1 (1A) of the present invention is provided on the boundary 12 of the flat light source 10 and the liquid crystal display device 10 provided with a plurality of flat light sources 10 and the liquid crystal display device 10 on the left and right and top and bottom. It is.
[0049]
6 (a) and 6 (b) show the present invention on the boundary 12 position of the flat light source 10 and the liquid crystal display device 10 in which a plurality of flat light sources 10 and the liquid crystal display device 10 are provided in the left, right, up and down or matrix form. It is the schematic plan view which provided the light body 1 (1A, 1B).
[0050]
As shown in FIG. 5 and FIG. 6A, when a plurality of planar light sources 10 and liquid crystal display devices 10 are provided on the left and right and top and bottom, the light guide 1A of the present invention shown in FIG. 1 is used. Then, the light guide 1 A is placed so as to straddle the two planar light sources 10 and the liquid crystal display device 10 at the position of the boundary 12 (broken line) between the adjacent planar light sources 10 and the liquid crystal display device 10. Thereby, the light emitted from the edge of the flat light source 10 or the liquid crystal display device 10 is guided from the incident end face 3 of the light guide 1A into the light guide plate 1A, and the light guide so that the presence of the light guide 1A is not recognized. Light is emitted from the exit surface 2 of 1A.
[0051]
That is, when a large number of conventional flat light sources and liquid crystal display devices such as large liquid crystal display displays and multi-images are connected to the left and right or up and down, the joints 12 of the individual flat light sources and liquid crystal display devices become conspicuous. It looked bad. In addition, the brightness of the joint 12 where the planar light sources are joined is abnormally low, causing spots in the brightness of the liquid crystal display, or appearing as dark lines in the joint 12 of the planar light source. However, as in the examples of FIG. 5 and FIG. 6A described above, by adopting the light guide plate 1A of this example, the above problems can be avoided, and the planar light sources and liquid crystal display devices provided on the left, right, and top and bottom can be avoided. The presence of the boundary 12 can be eliminated, and a completely large display device that is easy to see and has a good appearance can be obtained.
[0052]
Further, as shown in FIG. 6B, when a plurality of planar light sources 10 and liquid crystal display devices 10 are provided in a matrix, the light guide 1B of the present invention shown in FIG. 2 is used. And the light guide 1B is mounted in the position of the boundary 12 of the adjacent flat light source 10 or the liquid crystal display device 10 so that the four flat light sources 10 and the liquid crystal display device 10 may be straddled. Thereby, the light emitted from the edge of the planar light source 10 or the liquid crystal display device 10 is guided from the incident end surface portion 3 of the light guide 1 into the light guide 1B, and is guided so that the presence of the light guide 1B is not recognized. Light is emitted from the emission surface 2 of the body 1B.
[0053]
Furthermore, as shown in FIG. 7, when an ultra-large liquid crystal display, a multi-image, a flat light source, or the like is used in a matrix form, two types of light guides 1A and 1B should be used in combination. Can be enlarged without limitation. For example, a light guide 1B having a radiating surface 2 having a dozen shape is placed at the coupling point of the matrix that becomes a mesh, and the light emitting surface 2 has a linear shape between the coupling points of the light guides 1B. The light body 1A is placed. This eliminates the presence of the boundary 12 and makes it possible to obtain a single ultra-large display device that is easy to see and has a good appearance.
[0054]
That is, when a large number of conventional flat light sources and liquid crystal devices such as large liquid crystal display displays and multi-images are connected in a matrix, the joints 12 of the individual flat light sources and liquid crystal display devices become conspicuous and look good. Was bad. Moreover, the grid-like lines 12 are always recognized as viewed from across the grid, the brightness of the joint 12 where the planar light sources are joined together is abnormally low, causing spots in the brightness of the liquid crystal display, The light source joint 12 appears as a grid 12 dark line. However, by adopting the light guides 1A and 1B of this example as in the above-described examples of FIG. 6B and FIG. The presence of the boundary 12 of the device can be eliminated, and a single large display device that is easy to see and has a good appearance can be obtained.
[0055]
In addition to these flat light sources and liquid crystal display devices, light sources such as red, green, and blue (RGB) semiconductor light emitting elements (for example, semiconductor light emitting elements are formed into a rectangular package and emitted from a rectangular opening. .) Is a matrix-like large display or multi-image, the joints between the individual light sources are conspicuous, the appearance is poor, and the grid-like lines as seen from the grid are always recognized. However, by employing the light guide 1 of this example, it is possible to eliminate the boundary between the light sources provided in a matrix, and to obtain a single large display or multi-image that is easy to see and looks good.
[0056]
In this way, when a large number of flat light sources, liquid crystal display devices, etc. are conventionally used in a vertical, horizontal, and matrix form, the joints are conspicuous in order to connect the flat light sources, liquid crystal display devices, etc. There was a problem that the unevenness of brightness became conspicuous.
[0057]
Therefore, in the present invention, the light guide is disposed so as to straddle the planar light source, the liquid crystal display device, and the like at the joint position of each planar light source, the liquid crystal display device, and the like. Thereby, the light emitted from the flat light source or the liquid crystal display device or the like is guided from the two or four incident end surface portions of the light guide corresponding to the edge of the flat light source or the liquid crystal display device, and opposed to the incident end surface portions. Light guided into the light guide from one light emitting unit is emitted to the position of a joint between each planar light source and liquid crystal display device. As a result, the lines and grid lines of individual light sources are not noticeable, and one large display or a multi-image can be obtained completely with good appearance. Moreover, it is possible to easily reproduce a large display or multi-image having a free size.
[0058]
【The invention's effect】
 As described above, the light guide according to claim 1 is:An elongated rectangular exit surface, two incident end face portions having an elongated rectangular shape narrower than the exit surface at a position facing the exit surface or facing outside the exit surface, and a long side of the exit surface; The outer side surface or outer inclined surface portion connected to the outer long side of the incident end surface portion, the back surface portion forming a rectangular flat surface narrower than the output surface, the long side of the rear surface portion, and the inner length of the incident end surface portion An inner side surface portion or an inner inclined surface portion to which the side is connected, and two emission side surfaces, an incident end surface portion, a back surface portion, an outer side surface portion or an outer inclined surface portion, and two end side surface portions to which the inner side surface portion or the inner inclined surface portion is connected. Consists of
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Further, the portion where the long side of the emission surface is connected to the outer side surface portion or the outer inclined surface portion or / and the portion where the long side of the back surface portion is connected to the inner side surface portion or the inner inclined surface portion are rounded and are adjacent to each other. The boundary of the planar light source can be made inconspicuous. Thereby, it is possible to obtain a large screen and a multi-image surface that are easy to see and have a good appearance.
 In addition, it is possible to obtain a completely large display device that is easy to see and looks good by eliminating the presence of the boundary between the planar light source and the liquid crystal display device provided on the left and right and top and bottom. Moreover, it can be designed freely so that it can be easily increased in size without being limited by the number of flat light sources and liquid crystal display devices.
 Further, the boundary between the light guide itself is eliminated so that the presence of the light guide cannot be recognized. For this reason, there is no foreign material feeling of a light guide, and the emitted light from a flat light source or a liquid crystal display device and the emitted light from a light guide can be integrated completely.
[0059]
 Moreover, the light guide according to claim 2 is:A ten-shaped flat surface, four incident end surfaces having an L shape at a position facing the light emitting surface or a position facing outside the light emitting surface, and a quarter of the L-shaped side of the light emitting surface An outer side surface portion or an outer inclined surface portion that connects the outer L-shaped side of the incident end surface portion, a rear surface portion that forms a ten-shaped flat surface that is narrower than the exit surface, and an L-shaped side and incident end surface portion of the rear surface portion The inner side surface portion or the inner inclined surface portion to which the inner L-shaped side of each other is connected, the emission surface, the incident end surface portion, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion are connected. It consists of an end side part,
 A light deflecting element that refracts or / and totally reflects light is provided on the emission surface, the back surface portion, the outer side surface portion or the outer inclined surface portion, and the inner side surface portion or the inner inclined surface portion,
 Furthermore, the portion where the emission surface L-shaped side and the outer side surface portion or the outer inclined surface portion are connected or / and the portion where the inner L-shaped side of the incident end surface portion and the inner side surface portion or the inner inclined surface portion are connected have roundness. The boundary between adjacent planar light sources can be made inconspicuous. Thereby, it is possible to obtain a large screen and a multi-image surface that are easy to see and have a good appearance.
 In addition, it is possible to obtain a completely large display device that is easy to see and has a good appearance by eliminating the presence of a boundary between a planar light source and a liquid crystal display device provided in a matrix form on the left and right and top and bottom. Moreover, it can be designed freely so that it can be easily increased in size without being limited by the number of flat light sources and liquid crystal display devices.
 Further, the boundary between the light guide itself is eliminated so that the presence of the light guide cannot be recognized. For this reason, there is no foreign material feeling of a light guide, and the emitted light from a flat light source or a liquid crystal display device and the emitted light from a light guide can be integrated completely.
[0060]
 Furthermore, the light guide according to claim 3 is:The light deflecting element is composed of a convex or / and concave concave sphere and a part of an elliptical sphere, a triangular pyramid, a cone, a quadrangular pyramid, a triangular prism, a quadrangular prism, and a cylinder.SoIt is possible to select a necessary direction of emitted light from the emission surface, luminance, a combination thereof, and the like. For this reason, the light emitted from the exit surface due to the straight light from the incident end surface portion of the light guide and the light propagated by total reflection and the like are refracted and deflected, and are positioned at positions facing the boundary of the flat light source, the liquid crystal display device, etc. Emission light from a certain emission surface can be emitted uniformly.
[Brief description of the drawings]
FIG. 1A is a perspective view showing a schematic configuration of a light guide according to the present invention.
(B) View of the light guide of (a) as seen from the incident end face side (back side)
FIG. 2A is a perspective view schematically showing another configuration of the light guide according to the present invention.
(B) View of the light guide body of (a) as seen from the incident end face side (back side)
FIG. 3 is a cross-sectional view of a light guide according to the present invention.
FIG. 4 is a cross-sectional view of another example of a light guide according to the present invention.
FIG. 5 is a cross-sectional view of the light guide according to the present invention.
FIG. 6 is a schematic plan view of another embodiment of the light guide according to the present invention.
FIG. 7 is a schematic plan view of another embodiment of the light guide according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 (1A, 1B) ... Light guide, 2 ... Outgoing surface, 3 (3a, 3b) ... Incident end surface part, 4 ... Outer side surface part, Outer inclined surface part, 5 ... Back surface part, 6 ... Inner side surface part, Inner side inclination Surface portion 7... End side surface portion 8... Light deflecting element 10... Liquid crystal display device or flat light source 12 .. Joint, border, lattice shape, 34 ... Outer L-shaped side, 36 ... Inner L-shaped side, L1, L01, Lr, Lr1, Lr2, L0m1, Lmr1, Lmr2,.

Claims

A plurality of incident end face portions that take in emitted light from the edge portions of the planar light sources at positions adjacent to each other of the planar light sources constituting each unit of a large planar light source such as a multi-image surface or a plurality of liquid crystal screens, and these A light guide that emits light from a plurality of incident end face portions from one exit surface across the planar light sources adjacent to each other ,
The light guide has an emission surface that forms an elongated rectangular flat surface, and an elongated rectangular shape having a narrower width than the emission surface at a position facing the emission surface or a position facing the outside of the emission surface. Two incident end surface portions, an outer side surface portion or an outer inclined surface portion connecting the long side of the output end surface and the outer long side of the incident end surface portion, and a rectangular flat surface having a narrower width than the output surface. A back surface portion formed, an inner side surface portion or an inner inclined surface portion connecting a long side of the back surface portion and an inner long side of the incident end surface portion, the exit surface, the incident end surface portion, the back surface portion, and the outer side surface. Part or the outer inclined surface portion and the two inner side surface portions or the inner inclined surface portion are connected to the two end side surface portions,
Provided on the exit surface, the back surface portion, the outer side surface portion or the outer inclined surface portion and the inner side surface portion or the inner inclined surface portion are light deflecting elements that refract light or / and totally reflect light,
Further, the portion where the long side of the emission surface and the outer side surface portion or the outer inclined surface portion are connected or / and the portion where the long side of the back surface portion and the inner side surface portion or the inner inclined surface portion are connected are rounded. A light guide characterized by comprising.

A plurality of incident end face portions that take in emitted light from the edge portions of the planar light sources at positions adjacent to each other of the planar light sources constituting each unit of a large planar light source such as a multi-image surface or a plurality of liquid crystal screens, and these A light guide that emits light from a plurality of incident end face portions from one exit surface across the planar light sources adjacent to each other,
The light guide includes a light emitting surface having a ten-shaped flat surface, four incident end surface portions having an L shape at a position facing the light emitting surface or a position facing the outside of the light emitting surface, and the light emitting surface. An outer side surface portion or an outer inclined surface portion connecting an L-shaped side of a quarter of the surface and an outer L-shaped side of the incident end surface portion, and a back surface portion forming a ten-shaped flat surface narrower than the emission surface And an inner side surface portion or an inner inclined surface portion connecting the L-shaped side of the back surface portion and the inner L-shaped side of the incident end surface portion, the exit surface, the incident end surface portion, the back surface portion, and the outer side surface portion. Or consisting of four end side surfaces to which the outer inclined surface portion and the inner side surface portion or the inner inclined surface portion are connected,
Provided on the exit surface, the back surface portion, the outer side surface portion or the outer inclined surface portion and the inner side surface portion or the inner inclined surface portion are light deflecting elements that refract light or / and totally reflect light,
Further, the portion where the exit surface L-shaped side and the outer side surface portion or the outer inclined surface portion are connected or / and the portion where the inner L-shaped side of the incident end surface portion and the inner side surface portion or the inner inclined surface portion are connected are as follows: , light guide it characterized by having a rounded.

The light deflection element, convex or / and some well triangular pyramid of concave spherical and ellipsoid, conical, quadrangular pyramid, triangular prism, quadrangular prism, according to claim 1, wherein in that it consists of a cylinder Light guide.