JP3729012B2

JP3729012B2 - LED module

Info

Publication number: JP3729012B2
Application number: JP2000046951A
Authority: JP
Inventors: 達清内田; 昌男山口
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 2000-02-24
Filing date: 2000-02-24
Publication date: 2005-12-21
Anticipated expiration: 2020-02-24
Also published as: JP2001237463A

Description

【０００１】
【発明の属する技術分野】
この発明は、足元灯、表示灯、スポットライト、ウォールウォッシャ、建築化照明、スタンド、車内灯などの照明器具や、信号灯、視線誘導灯などに用いられるＬＥＤモジュールに関するものである。
【０００２】
【従来の技術】
従来、この種のＬＥＤモジュールとして実開平４−９２６６０（従来例１）や特開平６１−１８８８０３（従来例２）に示すものがあった。図１８は従来例１のＬＥＤモジュールの断面図、図１９は従来例２のＬＥＤ光源の断面図である。図１８では、ＬＥＤチップ５０を反射枠５１で囲みかつ透明樹脂によるレンズ５２で封止されている。また図１９では、ディスクリートＬＥＤ５３にレンズ５４を取付けている。
【０００３】
【発明が解決しようとする課題】
しかしながら、従来例１では反射枠５１で制御された光は前面のレンズ５２で屈折して出射するため、光源（ＬＥＤチップ）５０の発する光線のうち多くの部分が正面以外の方向に拡散してしまうという問題があった。
【０００４】
従来例２では光源の発する光を効率良く平行光に制御できるが、レンズ形状が複雑で製作し難い。またレンズ５４の長さが大きくなり、ＬＥＤ光源のサイズが大きくなってしまうという問題があった。
【０００５】
したがって、この発明の目的は、上記課題を解決し、必要最小限の立体角に効率良く光を反射する挟角配光のＬＥＤモジュールを提供することである。
【０００６】
【課題を解決するための手段】
上記課題を解決するためにこの発明の請求項１記載のＬＥＤモジュールは、光学系の軸ｃに配置されたＬＥＤ光源を反射面で囲みかつ封止物質で封止された配光部を備えたＬＥＤモジュールにおいて、封止物質のレンズ面Ｌｐが光学系の軸ｃを中心とする平面からなり、反射面が光学系の軸ｃに対して対称に配置されたそれぞれ凹曲面からなる内側の反射面Ｒｌと外側の反射面Ｒｕを持ち、レンズ面Ｌｐに沿った径方向の線分ｌｐは光学系の軸ｃと直交する直線上の線分であり、内側の反射面Ｒｌに沿った径方向の放物線ｒｌはその焦点が光源上の点ｐ０に位置し、放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は光源の設置に必要なスペースの半径以上で、放物線ｒｌの他方の端点ｐ２は、線分ｌｐを対称軸として光源上の点ｐ０と線対称の位置にある点をｐ０′、光源上の点ｐ０を起点とし光学系の軸ｃに対する臨界角θ′の角度で延びる直線と線分ｌｐとの交点をｐ５として、点ｐ０′と点ｐ５を結んで延長した直線上の点で線分ｌｐより光源側にあり、外側の反射面Ｒｕに沿った径方向の放物線ｒｕはその焦点が点ｐ０′に位置し、放物線ｒｕの一方の端点ｐ３は、点ｐ０′と点ｐ５を結んで延長した直線より光源側で、かつ放物線ｒｌより外側に位置し、放物線ｒｕの他方の端点ｐ４は線分ｌｐと放物線ｒｕの交点である。
【０００７】
上記の構成により、光源を発した光は２通りの経路を経て光学系の軸ｃに平行な光に制御される。まず、光源から反射面Ｒｌ方向に進む光は、反射面Ｒｌが光源上に焦点を持つ曲面であるため、反射により平行光に制御される。反射面Ｒｌで反射した光は、レンズ面Ｌｐに対しほぼ垂直に入射し、平行光のまま出射する。また、光源から反射面Ｒｌと点ｐ５の間に進む光は、まずレンズ面Ｌｐで全反射する。反射面Ｒｕは、その焦点がレンズ面Ｌｐでの反射による光源の虚像上に位置するように構成されているので、レンズ面Ｌｐで全反射された光は反射面Ｒｕにより平行光に制御される。反射面Ｒｕで反射した光は、レンズ面Ｌｐに対しほぼ垂直に入射するため、屈折による偏向はほとんどないまま平行光として出射する。これにより、点ｐ５の方向から反射面Ｒｌの端点ｐ１方向にいたるまでの範囲のほとんど光を、レンズなしで平行光に制御して出射させることが可能である。
【０００９】
請求項２記載のＬＥＤモジュールは、請求項１において、放物線ｒｌの端点ｐ１の光学系の軸ｃからの距離が、ＬＥＤ光源の設置に必要なスペースの半径に等しく、放物線ｒｕの一方の端点ｐ４の光学系の軸ｃからの距離は、光源上の点ｐ０と放物線ｒｌの端点ｐ２を結んで延長した直線と線分ｌｐの交点をｐ４′として、点ｐ４′の光学系の軸ｃからの距離以上とした。
【００１０】
これにより、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに入射する成分がなくなる。このため、光源から直接反射面Ｒｕに到達する光が存在する場合に、反射面Ｒｕはｐ０′方向から入射光のみ平行光に制御する機能を持つため、直接光源方向から入射した光は平行光に変換されないということがなくなる。
【００１１】
請求項３記載のＬＥＤモジュールは、光学系の軸ｃに配置されたＬＥＤ光源を反射面で囲みかつ封止物質で封止された配光部を備えたＬＥＤモジュールにおいて、前記封止物質のレンズ面が光学系の軸ｃを中心とする凸曲面からなる内側のレンズ面ＬＥと平面からなる外側のレンズ面Ｌｐを持ち、前記反射面が光学系の軸ｃに対して対称に配置されたそれぞれ凹曲面からなる内側の反射面Ｒｌと外側の反射面Ｒｕを持ち、内側のレンズ面ＬＥに沿った径方向の曲線ｌＥはその端点ｐ５′が前記光源上の点ｐ０を起点とし光学系の軸ｃに対する臨界角θ′の角度で延びる直線より外側にあり、外側のレンズ面Ｌｐに沿った径方向の線分ｌｐは点ｐ５′を通り光学系の軸ｃに直交する直線上の線分であり、内側の反射面Ｒｌに沿った径方向の放物線ｒｌはその焦点が前記光源上の点ｐ０に位置し、放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は曲線ｌＥの端点ｐ５′の光学系の軸ｃからの距離以上で、放物線ｒｌの他方の端点ｐ２は、線分ｌｐを対称軸として前記光源上の点ｐ０と線対称の位置にある点をｐ０′として、点ｐ０′と点ｐ５′を結んで延長した直線と放物線ｒｌの交点に位置し、外側の反射面Ｒｕに沿った径方向の放物線ｒｕはその焦点が点ｐ０′に位置し、放物線ｒｕの一方の端点ｐ３は、点ｐ０′と点ｐ５′を結んで延長した直線より前記光源側で、かつ放物線ｒｌより外側に位置し、放物線ｒｕの他方の端点ｐ４は線分ｌｐと放物線ｒｕの交点である。
【００１２】
このように、光源から点ｐ５の範囲を覆うレンズ面ＬＥを加えたので、この光学系では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが凸レンズをなしているため、光学系の軸ｃに集光される方向に屈折される。このため、光源から点ｐ５と光学系の軸に照射された光を平行光に制御する要素を与えていない場合に、この範囲に照射された光が平行光にならないうえに、レンズ面Ｌｐにおいて拡散する方向に屈折してしまうということがなくなる。
【００１３】
請求項４記載のＬＥＤモジュールは、請求項３において、曲線ｌＥは楕円の一部で長径ａＥと短径ｂＥの比が、ｎ′をレンズの媒質の屈折率、ｎを空気の屈折率として、ｂＥ／ａＥ＝（ｎ′^２−ｎ^２）^１ ^/ ^２／ｎ′を満たし、楕円の一方の焦点がＬＥＤ光源上の点ｐ０に位置し、楕円の中心は光学系の軸ｃ上で点ｐ０より照射方向側にあり、曲線ｌＥの端点ｐ５′は楕円とその短径ｂＥの交点である。
【００１４】
このようなレンズ面ＬＥの楕円レンズは焦点上から発した光を平行光に制御する性質があることが知られている。この光学系では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが上記のような性質を持つ楕円レンズであるため、平行光に制御される。このため、光学系の軸ｃから反射面Ｒｌの端点ｐ１方向にいたるまでの範囲の光をほとんど平行光に制御して出射させることが可能である。
【００１６】
請求項５記載のＬＥＤモジュールは、請求項４において、放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は、曲線ｌＥの端点ｐ５′の光学系の軸ｃからの距離と等しく、放物線ｒｕの一方の端点ｐ４の光学系の軸ｃからの距離は、ＬＥＤ光源上の点ｐ０と放物線ｒｌの端点ｐ２を結んで延長した直線と線分ｌｐの交点をｐ４′として、ｐ４′の光学系の軸ｃからの距離以上である。
【００１７】
これにより、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに入射する成分がなくなる。このため、光源から直接反射面Ｒｕに到達する光が存在する場合に、反射面Ｒｕはｐ０′方向から入射光のみ平行光に制御する機能を持つため、直接光源方向から入射した光は平行光に変換されないということがなくなる。
【００１８】
【発明の実施の形態】
この発明の第１の実施の形態のＬＥＤモジュールを図１ないし図３に基づいて説明する。図１はこの発明の第１の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図、図２（ａ）はこの発明の第１の実施の形態のＬＥＤモジュールを用いた信号灯の全体図、（ｂ）はランプ部の拡大図、（ｃ）は（ｂ）のＡ−Ａ′断面図、図３はこの発明の第１の実施の形態の作用説明図である。
【００１９】
図２（ａ）に示すように、この実施の形態では信号灯のランプ部１がＬＥＤモジュールで構成されている。ＬＥＤモジュールは、図２（ｂ）に示すように多数の配光部２を備え、その１つの構成を図２（ｃ）に示す。図２（ｃ）において、３はプリント基板、４はＬＥＤチップ、５は樹脂製反射枠、６はアルミニウム蒸着面、７はエポキシ樹脂である。ＬＥＤチップ４はＬＥＤ光源として用いられ、アルミニウム蒸着面６等で形成された反射面で囲まれ、エポキシ樹脂７等の封止物質で封止されている。
【００２０】
上記ＬＥＤモジュールの配光部２は、図１に示すように、封止物質のレンズ面Ｌｐが光学系の軸ｃを中心とする平面からなり、反射面が光学系の軸ｃに対して対称に配置されたそれぞれ凹曲面からなる内側の反射面Ｒｌと外側の反射面Ｒｕを持つ。この場合、封止物質は以下の条件を全て満たす線分ｌｐを、光学系の軸ｃを中心に回転させたレンズ面Ｌｐを持つ。ここで光学系の軸ｃとは、光源を通り光学系の照射方向へ延びる直線である。
【００２１】
（１）線分ｌｐは、光学系の軸ｃと直交する直線上の線分である。
【００２２】
（２）線分ｌｐの端点ｐ４は、線分ｌｐと放物線ｒｕの交点である。
【００２３】
（３）線分ｌｐの端点ｐ６は、線分ｌｐと光学系の軸ｃの交点である。
【００２４】
反射面は以下の条件を全て満たす放物線ｒｌを、光学系の軸ｃを中心に回転させた反射面Ｒｌを持つ。なおここでは、放物線ｒｌ，ｒｕとは、放物線の両端点を結んだ直線と放物線の間を通り、放物線の曲折と逆方向の曲折を持たない直線あるいは曲線とする放物線の近似線を含むものとする。
【００２５】
（１）放物線ｒｌの焦点が光源上の点ｐ０に位置する。
【００２６】
（２）放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は、光源の設置に必要な半径と等しいかより長い。
【００２７】
（３）放物線ｒｌの一方の端点ｐ２は、点ｐ０′とｐ５を結んで延長した直線上の点で、線分ｌｐより光源側にある。ここでｐ０′とｐ５は以下の条件を満たす点である。点ｐ０′は線分ｌｐを対称軸として、光源上のｐ０と線対称の位置にある点であり、平面Ｌｐによる光源の虚像上の点である。点ｐ５は、光源上の点ｐ０を起点とし、光学系の軸ｃに対して式１で与えられる臨界角θ′の角度で延びる直線と、線分ｌｐの交点である。なおここで、ｎ′はレンズの媒質の屈折率、ｎは空気の屈折率である。
【００２８】
θ′＝ｓｉｎ^-1（ｎ／ｎ′） …（式１）
また、反射面は以下の条件を全て満たす放物線ｒｕを、光学系の軸ｃを中心に回転させた反射面Ｒｕを持つ。
【００２９】
（１）放物線ｒｕの焦点が、平面Ｌｐによる光源の虚像上の点ｐ０′に位置する。
【００３０】
（２）放物線ｒｕの一方の端点ｐ３は、点ｐ０′とｐ５を結んで延長した直線より光源側で、なおかつ放物線ｒｌより外側（光源と反対側）に位置する。
【００３１】
（３）放物線ｒｕの一方の端点ｐ４は、線分ｌｐと放物線ｒｕの交点である。
【００３２】
次に上記構成の作用について説明する。図３に示すように、光源を発した光は２通りの経路をへて光学系の軸ｃに平行な光に制御される。まず、光源から反射面Ｒｌ方向に進む光は、反射面Ｒｌが光源上に焦点を持つ曲面であるため、反射により平行光に制御される。反射面Ｒｌで反射した光は、レンズ面Ｌｐに対しほぼ垂直に入射し、平行光のまま出射する（図３のＡの光線）。また、光源から反射面Ｒｌと点ｐ５の間に進む光は、まずレンズ面Ｌｐで全反射する。反射面Ｒｕは、その焦点がレンズ面Ｌｐでの反射による光源の虚像上に位置するように構成されているので、レンズ面Ｌｐで全反射された光は反射面Ｒｕにより平行光に制御される。反射面Ｒｕで反射した光は、レンズ面Ｌｐに対しほぼ垂直に入射するため、屈折による偏向はほとんどないまま平行光として出射する（図３のＢの光線）。この光学系では、光源からｐ５と光学系の軸ｃの間に照射された光は、特に制御しない。
【００３３】
以上のように、点ｐ５の方向から反射面Ｒｌの端点ｐ１方向にいたるまでの範囲のほとんど光を、レンズなしで平行光に制御して出射させることが可能である。このため、照明用光源として用いた場合、狭い範囲に光を照射できるため、照明効率の高い器具を実現できる。また、信号用として用いた場合、光学系正面の観察者から見ると反射面全域が発光しているように見え、輝度の高い信号灯を実現できる。
【００３４】
この発明の参考例を図４および図５に基づいて説明する。図４（ａ）はこの発明の参考例のＬＥＤモジュールを用いたダウンライト照明器具の全体図、（ｂ）はそのＡ−Ａ′断面図、図５はこの発明の参考例のＬＥＤモジュールの幾何学的構成を示す断面図である。
【００３５】
図４（ａ）に示すように、この参考例ではダウンライト照明器具がＬＥＤモジュールで構成されている。ＬＥＤモジュールは、多数の配光部２ａを備え、その１つの構成を図２（ｂ）に示す。図４（ｂ）において、３はプリント基板、４はＬＥＤチップ、５ａは樹脂製反射枠、６ａはアルミニウム蒸着面、７はエポキシ樹脂である。
【００３６】
上記ＬＥＤモジュールの配光部２ａは、図５に示すように、第１の実施の形態の条件に加えて、放物線ｒｕの一方の端点ｐ３が、点ｐ０′とｐ５を結んで延長した直線と、放物線ｒｌの交点に位置する。これにより、光学系は第１の実施の形態の範囲内で最も直径が小さくなる。
【００３７】
この発明の第２の実施の形態を図６および図７に基づいて説明する。図６（ａ）はこの発明の第３の実施の形態のＬＥＤモジュールを用いたフットライト照明器具の全体図、（ｂ）はそのＡ−Ａ′断面図、図７はこの発明の第２の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【００３８】
図６（ａ）に示すように、この実施の形態ではフットライト照明器具がＬＥＤモジュールで構成されている。ＬＥＤモジュールは、多数の配光部２ｂを備え、その１つの構成を図６（ｂ）に示す。図６（ｂ）において、３はプリント基板、４はＬＥＤチップ、５ｂは樹脂製反射枠、１１は銀蒸着面、７はエポキシ樹脂である。
【００３９】
上記ＬＥＤモジュールの配光部２ｂは、図７に示すように、第１の実施の形態の条件に加えて、放物線ｒｌの端点ｐ１の光学系の軸ｃからの距離が、光源の設置に必要な半径に等しい。また、放物線ｒｕの一方の端点ｐ４の光学系の軸ｃからの距離は、ｐ４′の光学系の軸ｃからの距離と等しいかより長い。ただしｐ４′は、光源上の点ｐ０と放物線ｒｌの端点ｐ２を結んで延長した直線と、直線ｌｐの交点である。
【００４０】
これにより、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに入射する成分がなくなる。このため、光源から直接反射面Ｒｕに到達する光が存在する場合に、反射面Ｒｕはｐ０′方向から入射光のみ平行光に制御する機能を持つため、直接光源方向から入射した光は平行光に変換されないということがなくなる。
【００４１】
この発明の第３の実施の形態のＬＥＤモジュールを図８ないし図１０に基づいて説明する。図８（ａ）はこの発明の第３の実施の形態のＬＥＤモジュールを用いた視線誘導灯の全体図、（ｂ）はそのＡ−Ａ′断面図、図９はこの発明の第３の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図、図１０はこの発明の第３の実施の形態の作用説明図である。
【００４２】
図８（ａ）に示すように、この実施の形態では視線誘導灯がＬＥＤモジュールで構成されている。ＬＥＤモジュールは、多数の配光部２ｃを備え、その１つの構成を図８（ｂ）に示す。図８（ｂ）において、３はプリント基板、４はＬＥＤチップ、１０はアルミニウム製反射枠、７ａはエポキシ樹脂である。
【００４３】
上記ＬＥＤモジュールの配光部２ｃは、図９に示すように、封止物質のレンズ面が光学系の軸ｃを中心とする凸曲面からなる内側のレンズ面ＬＥと平面からなる外側のレンズ面Ｌｐを持ち、反射面が光学系の軸ｃに対して対称に配置されたそれぞれ凹曲面からるな内側の反射面Ｒｌと外側の反射面Ｒｕを持つ。この場合、封止物質は以下の条件を全て満たす曲線ｌＥを、光学系の軸ｃを中心として回転させたレンズ面ＬＥを持つ。
【００４４】
（１）曲線ｌＥの端点ｐ５′は、光源上の点ｐ０を起点とし、光学系の軸ｃに対して第１の実施の形態の式１で与えられる臨界角θ′の角度で延びる直線より外側（光学系の軸ｃの反対側）に存在する。
【００４５】
（２）曲線ｌＥの端点ｐ６は光学系の軸ｃ上の点で、もう一方の端点ｐ５′から光学系の軸ｃ上におろした垂線と光学系の軸ｃとの交点より、光源からの距離が長い。
【００４６】
（３）曲線ｌＥは、点ｐ５′とｐ６を結んだ直線より、光源と反対側に凸な曲線である。
【００４７】
また、封止樹脂は以下の条件を全て満たす線分ｌｐを、光学系の軸ｃを中心に回転させたレンズ面Ｌｐを持つ。
【００４８】
（１）線分ｌｐは、点ｐ５′を通り光学系の軸ｃに直交する直線上の線分である。
【００４９】
（２）線分ｌｐの一方の端点は点ｐ５である。
【００５０】
（３）線分ｌｐの端点ｐ４は放物線ｒｕとの交点である。
【００５１】
反射面は以下の条件を全て満たす放物線ｒｌを、光学系の軸ｃを中心に回転させた反射面Ｒｌを持つ。
【００５２】
（１）放物線ｒｌの焦点が光源上の点ｐ０に位置する。
【００５３】
（２）放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は、曲線ｌＥの端点ｐ５′の光学系の軸ｃからの距離と、等しいかより長い。
【００５４】
（３）放物線ｒｌの一方の端点ｐ２は、点ｐ０′とｐ５を結んで延長した直線と放物線ｒｌの交点に位置する。ただし、点ｐ０′は線分ｌｐを含む直線を挟んで光源上の点ｐ０と線対称の位置にある点であり、平面Ｌｐによる光源の虚像上の点である。
【００５５】
また、反射面は以下の条件を全て満たす放物線ｒｕを、光学系の軸ｃを中心に回転させた反射面Ｒｕを持つ。
【００５６】
（１）放物線ｒｕの焦点が、平面Ｌｐによる光源の虚像上の点ｐ０′に位置する。
【００５７】
（２）放物線ｒｕの一方の端点ｐ３は、点ｐ０′とｐ５′を結んで延長した直線より光源側で、なおかつ放物線ｒｌより外側（光源と反対側）に位置する。
【００５８】
（３）放物線ｒｕの一方の端点ｐ４は、線分ｌｐと放物線ｒｕの交点である。
【００５９】
次に上記構成の作用について説明する。図１０に示すように、光源から点ｐ５の範囲を覆うレンズ面ＬＥを加えたので、この光学系では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが凸レンズをなしているため、光学系の軸ｃに集光される方向に屈折される（図１０のＣの光）。このため、光源から点ｐ５と光学系の軸ｃに照射された光を平行光に制御する要素を与えていない場合に、この範囲に照射された光が平行光にならないうえに、レンズ面Ｌｐにおいて拡散する方向に屈折してしまうということがなくなる。このため、照明用光源として用いた場合、狭い範囲に光を照射でき、周辺にはあまり光を漏らさないため、照明効率の高い器具を実現できる。また、信号用光源として用いた場合、光学系正面の観察者から見ると反射面全域が発光していて輝度が高く、なおかつそれ以外の方向にいる観察者からはあまり発光して見えない信号灯を実現できる。Ａ，Ｂの光の説明は第１の実施の形態と同様である。
【００６０】
この発明の第４の実施の形態を図１１ないし図１３に基づいて説明する。図１１（ａ）はこの発明の第４の実施の形態のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図、図１２はこの発明の第４の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図、図１３はこの発明の第４の実施の形態の作用説明図である。
【００６１】
図１１（ａ）に示すように、ＬＥＤモジュールは、多数の配光部２ｄを備え、その１つの構成を図１１（ｂ）に示す。図１１（ｂ）において、３はプリント基板、４はＬＥＤチップ、５は樹脂製反射枠、６はアルミニウム蒸着面、７ｂはエポキシ樹脂である。
【００６２】
上記ＬＥＤモジュールの配光部２ｄは、図１２に示すように、第３の実施の形態の条件に加えて、曲線ｌＥが、以下の条件を全て満たす楕円の一部である。
【００６３】
（１）楕円の長径ａＥと短径ｂＥの比が、ほぼ式２で求められる値を満たす。ここで、ｎ′はレンズの媒質の屈折率、ｎは空気の屈折率である。
【００６４】
ｂＥ／ａＥ＝（ｎ′²−ｎ²）^1/2／ｎ′ …（式２）
（２）楕円の一方の焦点がＬＥＤ光源上の点ｐ０に位置する。
【００６５】
（３）楕円の中心は、光学系の軸ｃ上で点ｐ０より照射方向側にある。
【００６６】
（４）曲線ｌＥの端点ｐ６は、楕円と光学系の軸ｃの２つの交点のうち、点ｐ０より照射方向側の点である。
【００６７】
（５）曲線ｌＥの端点ｐ５′は、楕円とその端径ｂＥの交点のうちの一方である。
【００６８】
次に上記構成の作用について説明する。図１３に示すように、このようなレンズ面ＬＥの楕円レンズは焦点上から発した光を平行光に制御する性質があることが知られている。この光学系では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが上記のような性質を持つ楕円レンズであるため、平行光に制御される（図１３のＣの光）。このため、光学系の軸ｃから反射面Ｒｌの端点ｐ１方向にいたるまでの範囲の光をほとんど平行光に制御して出射させることが可能である。Ａ，Ｂの光の説明は第１の実施の形態と同様である。
【００６９】
この発明の参考例を図１４および図１５に基づいて説明する。図１４（ａ）はこの発明の参考例のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図、図１５はこの発明の参考例のＬＥＤモジュールの幾何学的構成を示す断面図である。
【００７０】
図１４（ａ）に示すように、ＬＥＤモジュールは、多数の配光部２ｅを備え、その１つの構成を図１４（ｂ）に示す。図１４（ｂ）において、３はプリント基板、４はＬＥＤチップ、５ａは樹脂製反射枠、６ａはアルミニウム蒸着面、７ｂはエポキシ樹脂である。
【００７１】
上記ＬＥＤモジュールの配光部２ｅは、図１５に示すように、第４の実施の形態の条件に加えて、放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は、曲線ｌＥの端点ｐ５′の光学系の軸ｃからの距離と等しい。また、放物線ｒｕの一方の端点ｐ３が、点ｐ０′と点ｐ５′を結んで延長した直線と、放物線ｒｌの交点に位置する。これにより、光学系は第４の実施の形態の範囲内で最も直径が小さくなる。
【００７２】
この発明の第５の実施の形態を図１６および図１７に基づいて説明する。図１６（ａ）はこの発明の第５の実施の形態のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図、図１７はこの発明の第５の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【００７３】
図１６（ａ）に示すように、ＬＥＤモジュールは、配光部２ｆを備え、その構成を図１６（ｂ）に示す。図１６（ｂ）において、３はプリント基板、４はＬＥＤチップ、５ｂは樹脂製反射枠、６ｂはアルミニウム蒸着面、７ｂはエポキシ樹脂である。
【００７４】
上記ＬＥＤモジュールの配光部２ｆは、図１７に示すように、放物線ｒｌの一方の端点ｐ１の光学系の軸ｃからの距離は、曲線ｌＥの端点ｐ５′の光学系の軸ｃからの距離と等しい。また、放物線ｒｕの一方の端点ｐ４の光学系の軸ｃからの距離は、ｐ４′の光学系の軸ｃからの距離と等しいかより長い。ただしｐ４′は、光源上の点ｐ０と放物線ｒｌの端点ｐ２を結んで延長した直線と、線分ｌｐの交点である。
【００７５】
これにより、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに入射する成分がなくなる。このため、光源から直接反射面Ｒｕに到達する光が存在する場合に、反射面Ｒｕはｐ０′方向から入射光のみ平行光に制御する機能を持つため、直接光源方向から入射した光は平行光に変換されないということがなくなる。
【００７６】
なお、上記構成のＬＥＤモジュールは、実施の形態で示した照明器具以外の照明器具にも適用できる。また、反射枠は樹脂製の他に金属製でもよく、レンズはエポキシ樹脂以外の樹脂等でもよい。
【００７７】
【発明の効果】
この発明の請求項１記載のＬＥＤモジュールによれば、光源を発した光は２通りの経路を経て光学系の軸ｃに平行な光に制御される。これにより、点ｐ５の方向から反射面Ｒｌの端点ｐ１方向にいたるまでの範囲のほとんど光を、レンズなしで平行光に制御して出射させることが可能である。このため、照明用光源として用いた場合、狭い範囲に光を照射できるため、照明効率の高い器具を実現できる。また、信号用として用いた場合、光学系正面の観察者から見ると反射面全域が発光しているように見え、輝度の高い信号灯を実現できる。
【００７８】
また、レンズ表面で全反射するほとんどの光を、反射面による１回の反射で出射できるため、反射を繰り返すことによる光の損失が少なく、器具効率が良い。また、凸レンズを全く構成しないため、薄型の照明器具や信号灯を実現でき、製作が容易である。
【００８０】
請求項２では、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに到達する光束がなくなるので、より効率的に平行光に制御できる。また、反射面Ｒｌが光源に最も近いため、光源から反射面Ｒｌを見たときの立体角が最も大きくなり、より広い範囲の光束を平行光に制御できる。
【００８１】
この発明の請求項３記載のＬＥＤモジュールによれば、光源から点ｐ５の範囲を覆うレンズ面ＬＥを加えたので、この光学系では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが凸レンズをなしているため、光学系の軸ｃに集光される方向に屈折され、レンズ表面に到達して拡散していた光を集光できる。このため、照明用光源として用いた場合、狭い範囲に光を照射でき、周辺にはあまり光を漏らさないため、照明効率の高い器具を実現できる。また、信号用光源として用いた場合、光学系正面の観察者から見ると反射面全域が発光していて輝度が高く、なおかつそれ以外の方向にいる観察者からはあまり発光して見えない信号灯を実現できる。
【００８２】
また、レンズ表面で全反射するほとんどの光を、反射面による１回の反射で出射できるため、反射を繰り返すことによる光の損失が少なく、器具効率が良い。また、従来例２に比較してレンズ形状が単純であるため、製作が容易である。
【００８３】
請求項４では、光源から反射面Ｒｌの端点ｐ１と点ｐ５′の間に照射される光については、請求項１と同様の仕組みで平行光に制御される。それに加えて、レンズ面ＬＥの方向に照射された光については、レンズ面ＬＥが焦点上から発した光を平行光に制御する性質を持つ楕円レンズであるため、平行光に制御される。このため、光学系の軸ｃから反射面Ｒｌの端点ｐ１方向にいたるまでの範囲の光をほとんど平行光に制御して出射させることが可能である。
【００８５】
請求項５では、光源から見た場合に反射面Ｒｕは反射面Ｒｌの影に隠れ、光源から直接反射面Ｒｕに到達する光束がなくなるので、光源から発する光をより効率的に平行光に制御できる。また、反射面Ｒｌが光源に最も近いため、光源から反射面Ｒｌを見たときの立体角が最も大きくなり、より広い範囲の光束を平行光に制御できる。
【図面の簡単な説明】
【図１】この発明の第１の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図２】（ａ）はこの発明の第１の実施の形態のＬＥＤモジュールを用いた信号灯の全体図、（ｂ）はランプ部の拡大図、（ｃ）は（ｂ）のＡ−Ａ′断面図である。
【図３】この発明の第１の実施の形態の作用説明図である。
【図４】（ａ）はこの発明の参考例のＬＥＤモジュールを用いたダウンライト照明器具の全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図５】この発明の参考例のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図６】この発明の第２の実施の形態のＬＥＤモジュールを用いたフットライト照明器具の全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図７】この発明の第２の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図８】（ａ）はこの発明の第３の実施の形態のＬＥＤモジュールを用いた視線誘導灯の全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図９】この発明の第３の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図１０】この発明の第３の実施の形態の作用説明図である。
【図１１】（ａ）はこの発明の第４の実施の形態のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図１２】この発明の第４の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図１３】この発明の第４の実施の形態の作用説明図である。
【図１４】（ａ）はこの発明の参考例のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図１５】この発明の参考例のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図１６】（ａ）はこの発明の第５の実施の形態のＬＥＤモジュールの全体図、（ｂ）はそのＡ−Ａ′断面図である。
【図１７】この発明の第５の実施の形態のＬＥＤモジュールの幾何学的構成を示す断面図である。
【図１８】従来例１のＬＥＤモジュールの断面図である。
【図１９】従来例２のＬＥＤ光源の断面図である。
【符号の説明】
４ＬＥＤチップ
５樹脂製反射枠
６アルミニウム蒸着面
７エポキシ樹脂
ｃ光学系の軸
Ｌｐレンズ面
ｌｐ線分
Ｒｌ反射面
ｒｌ放物線
Ｒｕ反射面
ｒｕ放物線
θ′ 臨界角[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lighting device such as a foot lamp, an indicator lamp, a spotlight, a wall washer, an architectural lamp, a stand, an interior lamp, an LED module used for a signal lamp, a line-of-sight guide lamp, and the like.
[0002]
[Prior art]
Conventionally, as this type of LED module, there are those shown in Japanese Utility Model Laid-Open No. 4-92660 (Conventional Example 1) and Japanese Patent Laid-Open No. 61-188803 (Conventional Example 2). 18 is a cross-sectional view of the LED module of Conventional Example 1, and FIG. 19 is a cross-sectional view of the LED light source of Conventional Example 2. In FIG. 18, the LED chip 50 is surrounded by a reflective frame 51 and sealed with a lens 52 made of a transparent resin. In FIG. 19, a lens 54 is attached to the discrete LED 53.
[0003]
[Problems to be solved by the invention]
However, in Conventional Example 1, the light controlled by the reflection frame 51 is refracted and emitted by the front lens 52, so that many parts of the light emitted from the light source (LED chip) 50 are diffused in directions other than the front. There was a problem that.
[0004]
In Conventional Example 2, the light emitted from the light source can be efficiently controlled to parallel light, but the lens shape is complicated and difficult to manufacture. Further, there is a problem that the length of the lens 54 is increased and the size of the LED light source is increased.
[0005]
Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a narrow-angle light distribution LED module that efficiently reflects light to the minimum required solid angle.
[0006]
[Means for Solving the Problems]
  In order to solve the above-described problem, an LED module according to claim 1 of the present invention includes a light distribution unit that surrounds an LED light source disposed on an axis c of an optical system with a reflecting surface and is sealed with a sealing material. In the LED module, the lens surface Lp of the sealing material is a flat surface centered on the axis c of the optical system, and the reflective surfaces are inner reflective surfaces each having a concave curved surface arranged symmetrically with respect to the axis c of the optical system. R1 and the outer reflecting surface Ru, and the radial line segment lp along the lens surface Lp is a straight line segment orthogonal to the axis c of the optical system, and the radial line segment lp along the inner reflecting surface Rl. The focal point of the parabola rl is located at a point p0 on the light source, and the distance from one end point p1 of the parabola rl to the axis c of the optical system is necessary for installing the light source.Of spaceThe other end point p2 of the parabola rl is equal to or greater than the radius, and the point c0 ′ on the light source is symmetrical to the point p0 on the light source with the line segment lp as the axis of symmetry, and the axis c of the optical system starting from the point p0 on the light source. An intersection of a straight line extending at a critical angle θ ′ with respect to the line segment lp and p5 is a point on a straight line extending from the point p0 ′ and the point p5 and extending from the line segment lp to the light source side. The radial parabola ru along Ru is positioned at the point p0 ′, and one end point p3 of the parabola ru is closer to the light source than the straight line connecting the points p0 ′ and p5 and from the parabola rl. Located on the outside, the other end point p4 of the parabola ru is the intersection of the line segment lp and the parabola ru.
[0007]
With the above configuration, light emitted from the light source is controlled to light parallel to the axis c of the optical system through two paths. First, light traveling from the light source in the direction of the reflection surface Rl is controlled to be parallel light by reflection because the reflection surface Rl is a curved surface having a focal point on the light source. The light reflected by the reflecting surface Rl is incident substantially perpendicular to the lens surface Lp and is emitted as parallel light. Further, the light traveling between the reflection surface Rl and the point p5 from the light source is first totally reflected by the lens surface Lp. Since the reflecting surface Ru is configured such that its focal point is positioned on the virtual image of the light source reflected by the lens surface Lp, the light totally reflected by the lens surface Lp is controlled to be parallel light by the reflecting surface Ru. . Since the light reflected by the reflecting surface Ru is incident substantially perpendicular to the lens surface Lp, it is emitted as parallel light with almost no deflection due to refraction. As a result, it is possible to emit almost all the light in the range from the direction of the point p5 to the direction of the end point p1 of the reflecting surface Rl as parallel light without a lens.
[0009]
  Claim2The LED module according to claim1, The distance from the optical system axis c of the end point p1 of the parabola rl is equal to the radius of the space necessary for installing the LED light source, and the distance from the optical system axis c of one end point p4 of the parabola ru The intersection of the straight line lp extending from the upper point p0 and the end point p2 of the parabola rl and the line segment lp is defined as p4 ', and the distance from the point c4' to the axis c of the optical system is equal to or greater.
[0010]
Thereby, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl, and the component that directly enters the reflection surface Ru from the light source is eliminated. For this reason, when there is light that directly reaches the reflection surface Ru from the light source, the reflection surface Ru has a function of controlling only incident light from the p0 ′ direction to parallel light, and thus light incident directly from the light source direction is parallel light. It is no longer converted to.
[0011]
  Claim3The LED module described includes an LED module that includes a light distribution unit that surrounds an LED light source disposed on an axis c of an optical system with a reflective surface and is sealed with a sealing material, and the lens surface of the sealing material is optical. Each lens has an inner lens surface LE formed of a convex curved surface centered on the system axis c and an outer lens surface Lp formed of a flat surface, and the reflecting surfaces are symmetrically arranged with respect to the axis c of the optical system. The radial curve lE along the inner lens surface LE has a critical point with respect to the axis c of the optical system starting from the point p0 on the light source. The line segment lp in the radial direction along the outer lens surface Lp that is outside the straight line extending at the angle θ ′ is a straight line segment that passes through the point p5 ′ and is orthogonal to the axis c of the optical system. The radial parabola rl along the reflective surface Rl of Is located at a point p0 on the light source, and the distance from the optical system axis c of one end point p1 of the parabola rl is equal to or greater than the distance from the optical system axis c of the end point p5 'of the curve lE. The other end point p2 is a straight line extending from the point p0 'to the point p5' and a parabola rl with the point symmetric with respect to the point p0 on the light source as a point p0 'with the line segment lp as the axis of symmetry. The parabola ru in the radial direction along the outer reflecting surface Ru is located at the intersection point, the focal point thereof is located at the point p0 ′, and one end point p3 of the parabola ru extends by connecting the points p0 ′ and p5 ′. The other end point p4 of the parabola ru is located at the light source side of the straight line and outside the parabola rl, and is the intersection of the line segment lp and the parabola ru.
[0012]
Thus, since the lens surface LE covering the range of the point p5 from the light source is added, in this optical system, the light irradiated between the end point p1 and the point p5 ′ of the reflection surface Rl from the light source is claimed in claim 1. It is controlled to parallel light by the same mechanism. In addition, the light irradiated in the direction of the lens surface LE is refracted in the direction of focusing on the axis c of the optical system because the lens surface LE forms a convex lens. For this reason, when the element which controls the light irradiated to the point p5 and the axis | shaft of an optical system from a light source to the parallel light is not given, the light irradiated to this range does not turn into a parallel light, but in the lens surface Lp. There will be no refraction in the direction of diffusion.
[0013]
  Claim 4The LED module according to claim3The curve lE is a part of an ellipse, and the ratio of the major axis aE to the minor axis bE is nE is the refractive index of the lens medium and n is the refractive index of the air, and bE / aE = (n ′²-N²)¹ ^/ ²/ N ′, one focus of the ellipse is located at the point p0 on the LED light source, the center of the ellipse is on the irradiation direction side from the point p0 on the axis c of the optical system, and the end point p5 ′ of the curve lE is the ellipse And its minor axis bE.
[0014]
It is known that such an elliptic lens having a lens surface LE has a property of controlling light emitted from the focal point to parallel light. In this optical system, light emitted from the light source between the end points p1 and p5 ′ of the reflecting surface Rl is controlled to parallel light by the same mechanism as in the first aspect. In addition, the light irradiated in the direction of the lens surface LE is controlled to be parallel light because the lens surface LE is an elliptic lens having the above properties. For this reason, light in a range from the axis c of the optical system to the direction of the end point p1 of the reflection surface Rl can be controlled to be almost parallel light and emitted.
[0016]
  Claim5The LED module according to claim4, The distance from one end point p1 of the parabola rl from the axis c of the optical system is equal to the distance from the axis c of the end point p5 ′ of the curve lE to the axis of the optical system at one end point p4 of the parabola ru. The distance from c is equal to or greater than the distance from the axis c of the optical system of p4 ′, where p4 ′ is the intersection of a straight line extending from the point p0 on the LED light source and the end point p2 of the parabola rl and the line segment lp.
[0017]
Thereby, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl, and the component that directly enters the reflection surface Ru from the light source is eliminated. For this reason, when there is light that directly reaches the reflection surface Ru from the light source, the reflection surface Ru has a function of controlling only incident light from the p0 ′ direction to parallel light, and thus light incident directly from the light source direction is parallel light. It is no longer converted to.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
An LED module according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view showing a geometric configuration of an LED module according to the first embodiment of the present invention. FIG. 2A is an overall view of a signal lamp using the LED module according to the first embodiment of the present invention. (B) is an enlarged view of a lamp part, (c) is AA 'sectional drawing of (b), FIG. 3 is operation | movement explanatory drawing of 1st Embodiment of this invention.
[0019]
As shown to Fig.2 (a), in this embodiment, the lamp | ramp part 1 of a signal lamp is comprised with the LED module. The LED module includes a large number of light distribution units 2 as shown in FIG. 2B, and one configuration thereof is shown in FIG. In FIG. 2C, 3 is a printed circuit board, 4 is an LED chip, 5 is a resin reflecting frame, 6 is an aluminum vapor deposition surface, and 7 is an epoxy resin. The LED chip 4 is used as an LED light source, is surrounded by a reflective surface formed by an aluminum vapor deposition surface 6 or the like, and is sealed with a sealing material such as an epoxy resin 7 or the like.
[0020]
As shown in FIG. 1, the light distribution part 2 of the LED module has a lens surface Lp of a sealing material having a plane centered on the axis c of the optical system, and the reflection surface is symmetric with respect to the axis c of the optical system Each having an inner reflection surface Rl and an outer reflection surface Ru each formed of a concave curved surface. In this case, the sealing material has a lens surface Lp obtained by rotating a line segment lp satisfying all the following conditions around the axis c of the optical system. Here, the axis c of the optical system is a straight line that passes through the light source and extends in the irradiation direction of the optical system.
[0021]
(1) The line segment lp is a line segment on a straight line orthogonal to the axis c of the optical system.
[0022]
(2) The end point p4 of the line segment lp is an intersection of the line segment lp and the parabola ru.
[0023]
(3) The end point p6 of the line segment lp is an intersection of the line segment lp and the axis c of the optical system.
[0024]
The reflecting surface has a reflecting surface Rl obtained by rotating a parabola rl that satisfies all of the following conditions around the axis c of the optical system. Here, the parabolas rl and ru include an approximate line of a parabola that is a straight line or a curve that passes between a parabola and a straight line that connects both end points of the parabola and does not have a reverse bending to the parabola.
[0025]
(1) The focal point of the parabola rl is located at the point p0 on the light source.
[0026]
(2) The distance of one end point p1 of the parabola rl from the axis c of the optical system is equal to or longer than the radius necessary for installing the light source.
[0027]
(3) One end point p2 of the parabola rl is a point on a straight line extending from the points p0 ′ and p5 and is closer to the light source than the line segment lp. Here, p0 ′ and p5 are points that satisfy the following conditions. The point p0 ′ is a point on the light source in a line symmetric position with respect to p0 with the line segment lp as the symmetry axis, and is a point on the virtual image of the light source by the plane Lp. Point p5 is the intersection of a line segment lp and a straight line starting from point p0 on the light source and extending at an angle of critical angle θ ′ given by equation 1 with respect to axis c of the optical system. Here, n ′ is the refractive index of the lens medium, and n is the refractive index of air.
[0028]
θ ′ = sin^-1(N / n ′) (Formula 1)
The reflecting surface has a reflecting surface Ru obtained by rotating a parabola ru that satisfies all of the following conditions about the axis c of the optical system.
[0029]
(1) The focal point of the parabola ru is located at a point p0 ′ on the virtual image of the light source by the plane Lp.
[0030]
(2) One end point p3 of the parabola ru is located on the light source side from the straight line extending from the points p0 'and p5 and outside the parabola rl (opposite the light source).
[0031]
(3) One end point p4 of the parabola ru is an intersection of the line segment lp and the parabola ru.
[0032]
Next, the operation of the above configuration will be described. As shown in FIG. 3, the light emitted from the light source is controlled to light parallel to the axis c of the optical system through two paths. First, light traveling from the light source in the direction of the reflection surface Rl is controlled to be parallel light by reflection because the reflection surface Rl is a curved surface having a focal point on the light source. The light reflected by the reflecting surface Rl is incident substantially perpendicular to the lens surface Lp and is emitted as parallel light (the light beam A in FIG. 3). Further, the light traveling between the reflection surface Rl and the point p5 from the light source is first totally reflected by the lens surface Lp. Since the reflecting surface Ru is configured such that its focal point is positioned on the virtual image of the light source reflected by the lens surface Lp, the light totally reflected by the lens surface Lp is controlled to be parallel light by the reflecting surface Ru. . Since the light reflected by the reflecting surface Ru is incident substantially perpendicular to the lens surface Lp, it is emitted as parallel light with almost no deflection due to refraction (the light beam B in FIG. 3). In this optical system, the light emitted from the light source between p5 and the axis c of the optical system is not particularly controlled.
[0033]
As described above, almost all light in the range from the direction of the point p5 to the direction of the end point p1 of the reflecting surface Rl can be controlled and emitted as parallel light without a lens. For this reason, since it can irradiate light to a narrow range when used as a light source for illumination, an instrument with high illumination efficiency can be realized. In addition, when used as a signal, when viewed from an observer in front of the optical system, the entire reflecting surface appears to emit light, and a high-intensity signal lamp can be realized.
[0034]
  Of this inventionReference exampleWill be described with reference to FIGS. FIG. 4 (a) shows the present invention.Reference example(B) is a sectional view taken along the line AA ′ of FIG. 5, and FIG.Reference exampleIt is sectional drawing which shows the geometrical structure of LED module.
[0035]
  As shown in FIG.Reference exampleThen, the downlight lighting fixture is comprised with the LED module. The LED module includes a large number of light distribution units 2a, and one configuration thereof is shown in FIG. In FIG. 4B, 3 is a printed circuit board, 4 is an LED chip, 5a is a resin reflecting frame, 6a is an aluminum vapor deposition surface, and 7 is an epoxy resin.
[0036]
As shown in FIG. 5, in addition to the conditions of the first embodiment, the light distribution unit 2a of the LED module includes a straight line in which one end point p3 of the parabola ru extends between points p0 ′ and p5. , Located at the intersection of parabola rl. As a result, the optical system has the smallest diameter within the range of the first embodiment.
[0037]
  First of this invention2The embodiment will be described with reference to FIGS. FIG. 6A is an overall view of a footlight illuminator using the LED module of the third embodiment of the present invention, FIG. 6B is a sectional view taken along the line AA ′, and FIG.2It is sectional drawing which shows the geometric structure of the LED module of embodiment.
[0038]
As shown to Fig.6 (a), in this embodiment, the footlight lighting fixture is comprised with the LED module. The LED module includes a large number of light distribution portions 2b, and one configuration thereof is shown in FIG. In FIG. 6B, 3 is a printed circuit board, 4 is an LED chip, 5b is a resin reflecting frame, 11 is a silver vapor deposition surface, and 7 is an epoxy resin.
[0039]
As shown in FIG. 7, the light distribution unit 2b of the LED module needs a distance from the axis c of the optical system at the end point p1 of the parabola rl in addition to the conditions of the first embodiment. Equal to the radius. Further, the distance from one end point p4 of the parabola ru to the axis c of the optical system is equal to or longer than the distance of p4 ′ from the axis c of the optical system. However, p4 'is an intersection of a straight line lp and a straight line extending by connecting the point p0 on the light source and the end point p2 of the parabola rl.
[0040]
Thereby, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl, and the component that directly enters the reflection surface Ru from the light source is eliminated. For this reason, when there is light that directly reaches the reflection surface Ru from the light source, the reflection surface Ru has a function of controlling only incident light from the p0 ′ direction to parallel light, and thus light incident directly from the light source direction is parallel light. It is no longer converted to.
[0041]
  First of this invention3The LED module of this embodiment will be described with reference to FIGS. FIG. 8 (a) shows the first aspect of the present invention.3FIG. 9 is an overall view of a line-of-sight guide lamp using the LED module of the embodiment, FIG.3Sectional drawing which shows the geometrical structure of the LED module of embodiment of FIG., FIG.3It is operation | movement explanatory drawing of this embodiment.
[0042]
As shown in FIG. 8A, in this embodiment, the line-of-sight guide lamp is formed of an LED module. The LED module includes a large number of light distribution portions 2c, and one configuration thereof is shown in FIG. In FIG. 8B, 3 is a printed circuit board, 4 is an LED chip, 10 is an aluminum reflecting frame, and 7a is an epoxy resin.
[0043]
As shown in FIG. 9, the light distribution part 2c of the LED module includes an inner lens surface LE that is a convex curved surface centered on the axis c of the optical system, and an outer lens surface that is a plane. Each of the reflecting surfaces has an inner reflecting surface Rl and an outer reflecting surface Ru, each of which is made up of a concave curved surface, which has Lp and the reflecting surfaces are arranged symmetrically with respect to the axis c of the optical system. In this case, the sealing material has a lens surface LE obtained by rotating a curve lE that satisfies all the following conditions about the axis c of the optical system.
[0044]
(1) The end point p5 ′ of the curve lE starts from the point p0 on the light source and extends from the straight line extending at an angle of the critical angle θ ′ given by the expression 1 of the first embodiment with respect to the axis c of the optical system. It exists on the outside (opposite side of the axis c of the optical system).
[0045]
(2) The end point p6 of the curve lE is a point on the axis c of the optical system. From the intersection of the perpendicular line drawn on the axis c of the optical system from the other end point p5 'and the axis c of the optical system, Long distance.
[0046]
(3) The curve lE is a curve that is convex to the opposite side of the light source from the straight line connecting the points p5 ′ and p6.
[0047]
The sealing resin has a lens surface Lp obtained by rotating a line segment lp satisfying all the following conditions around the axis c of the optical system.
[0048]
(1) The line segment lp is a line segment on a straight line passing through the point p5 'and orthogonal to the axis c of the optical system.
[0049]
(2) One end point of the line segment lp is a point p5.
[0050]
(3) The end point p4 of the line segment lp is an intersection with the parabola ru.
[0051]
The reflecting surface has a reflecting surface Rl obtained by rotating a parabola rl satisfying all of the following conditions around the axis c of the optical system.
[0052]
(1) The focal point of the parabola rl is located at the point p0 on the light source.
[0053]
(2) The distance of one end point p1 of the parabola rl from the axis c of the optical system is equal to or longer than the distance of the end point p5 ′ of the curve lE from the axis c of the optical system.
[0054]
(3) One end point p2 of the parabola rl is located at the intersection of a straight line extending from the points p0 'and p5 and the parabola rl. However, the point p0 ′ is a point on the light source with respect to the point p0 on the light source across the straight line including the line segment lp, and is a point on the virtual image of the light source by the plane Lp.
[0055]
The reflecting surface has a reflecting surface Ru obtained by rotating a parabola ru that satisfies all of the following conditions about the axis c of the optical system.
[0056]
(1) The focal point of the parabola ru is located at a point p0 ′ on the virtual image of the light source by the plane Lp.
[0057]
(2) One end point p3 of the parabola ru is located on the light source side with respect to the straight line extending from the points p0 'and p5' and outside the parabola rl (on the opposite side to the light source).
[0058]
(3) One end point p4 of the parabola ru is an intersection of the line segment lp and the parabola ru.
[0059]
Next, the operation of the above configuration will be described. As shown in FIG. 10, since the lens surface LE covering the range of the point p5 from the light source is added, in this optical system, the light irradiated between the end point p1 and the point p5 ′ of the reflection surface Rl from the light source is It is controlled to parallel light by the same mechanism as in the first aspect. In addition, the light irradiated in the direction of the lens surface LE is refracted in the direction of focusing on the axis c of the optical system because the lens surface LE forms a convex lens (the light of C in FIG. 10). ). For this reason, when the element which controls the light irradiated from the light source to the point p5 and the axis c of the optical system to parallel light is not given, the light irradiated to this range does not become parallel light, and the lens surface Lp. Refracting in the diffusing direction is eliminated. For this reason, when it is used as a light source for illumination, it is possible to irradiate light in a narrow range and does not leak much light to the periphery, so that an instrument with high illumination efficiency can be realized. In addition, when used as a signal light source, when viewed from an observer in front of the optical system, a signal lamp that emits light from the entire reflecting surface and has high brightness, and is not visible by an observer in other directions. realizable. The description of A and B light is the same as in the first embodiment.
[0060]
  First of this invention4The embodiment will be described with reference to FIGS. FIG. 11 (a) shows the first aspect of the present invention.4FIG. 12 is an overall view of the LED module according to the embodiment of the present invention, FIG.4Sectional drawing which shows the geometrical structure of the LED module of embodiment of FIG. 13, FIG.4It is operation | movement explanatory drawing of this embodiment.
[0061]
As shown in FIG. 11 (a), the LED module includes a number of light distribution units 2d, and one configuration thereof is shown in FIG. 11 (b). In FIG. 11B, 3 is a printed circuit board, 4 is an LED chip, 5 is a resin reflecting frame, 6 is an aluminum vapor deposition surface, and 7b is an epoxy resin.
[0062]
  As shown in FIG. 12, the light distribution part 2d of the LED module3In addition to the conditions of the embodiment, the curve lE is a part of an ellipse that satisfies all of the following conditions.
[0063]
(1) The ratio of the major axis aE to the minor axis bE of the ellipse almost satisfies the value obtained by Equation 2. Here, n ′ is the refractive index of the lens medium, and n is the refractive index of air.
[0064]
bE / aE = (n ′²-N²)^1/2/ N '(Formula 2)
(2) One focal point of the ellipse is located at a point p0 on the LED light source.
[0065]
(3) The center of the ellipse is on the irradiation direction side of the point p0 on the axis c of the optical system.
[0066]
(4) The end point p6 of the curve lE is a point closer to the irradiation direction than the point p0 among the two intersections of the ellipse and the axis c of the optical system.
[0067]
(5) The end point p5 'of the curve lE is one of the intersections of the ellipse and its end diameter bE.
[0068]
Next, the operation of the above configuration will be described. As shown in FIG. 13, it is known that such an elliptical lens having a lens surface LE has a property of controlling light emitted from the focal point to parallel light. In this optical system, light emitted from the light source between the end points p1 and p5 ′ of the reflecting surface Rl is controlled to parallel light by the same mechanism as in the first aspect. In addition, the light irradiated in the direction of the lens surface LE is controlled to be parallel light because the lens surface LE is an elliptic lens having the above-described properties (light C in FIG. 13). For this reason, light in a range from the axis c of the optical system to the direction of the end point p1 of the reflection surface Rl can be controlled to be almost parallel light and emitted. The description of A and B light is the same as in the first embodiment.
[0069]
  Of this inventionReference exampleWill be described with reference to FIGS. 14 and 15. FIG. 14 (a) shows the present invention.Reference example(B) is a cross-sectional view taken along the line AA 'of FIG. 15, and FIG.Reference exampleIt is sectional drawing which shows the geometrical structure of LED module.
[0070]
As shown to Fig.14 (a), an LED module is provided with many light distribution parts 2e, and the structure of one is shown in FIG.14 (b). In FIG. 14B, 3 is a printed circuit board, 4 is an LED chip, 5a is a resin reflective frame, 6a is an aluminum vapor deposition surface, and 7b is an epoxy resin.
[0071]
  As shown in FIG. 15, the light distribution part 2e of the LED module4In addition to the conditions of the embodiment, the distance from the optical system axis c of one end point p1 of the parabola rl is equal to the distance from the optical system axis c of the end point p5 ′ of the curve lE. In addition, one end point p3 of the parabola ru is located at the intersection of the parabola rl and a straight line connecting the points p0 ′ and p5 ′. This allows the optical system to4The diameter becomes the smallest within the range of the embodiment.
[0072]
  First of this invention5The embodiment will be described with reference to FIGS. 16 and 17. FIG. FIG. 16 (a) shows the first aspect of the present invention.5FIG. 17 is an overall view of the LED module according to the embodiment, FIG.5It is sectional drawing which shows the geometric structure of the LED module of embodiment.
[0073]
As shown in FIG. 16A, the LED module includes a light distribution unit 2f, and the configuration thereof is shown in FIG. In FIG. 16B, 3 is a printed circuit board, 4 is an LED chip, 5b is a resin reflective frame, 6b is an aluminum vapor deposition surface, and 7b is an epoxy resin.
[0074]
As shown in FIG. 17, the light distribution unit 2f of the LED module has a distance from one end point p1 of the parabola rl from the axis c of the optical system to a distance from the axis c of the end point p5 ′ of the curve lE. Is equal to Further, the distance from one end point p4 of the parabola ru to the axis c of the optical system is equal to or longer than the distance of p4 ′ from the axis c of the optical system. However, p4 'is an intersection of a line segment lp and a straight line extending by connecting the point p0 on the light source and the end point p2 of the parabola rl.
[0075]
Thereby, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl, and the component that directly enters the reflection surface Ru from the light source is eliminated. For this reason, when there is light that directly reaches the reflection surface Ru from the light source, the reflection surface Ru has a function of controlling only incident light from the p0 ′ direction to parallel light, and thus light incident directly from the light source direction is parallel light. It is no longer converted to.
[0076]
Note that the LED module having the above configuration can be applied to lighting fixtures other than the lighting fixtures described in the embodiment. The reflection frame may be made of metal in addition to resin, and the lens may be made of resin other than epoxy resin.
[0077]
【The invention's effect】
According to the LED module of the first aspect of the present invention, the light emitted from the light source is controlled to light parallel to the axis c of the optical system through two paths. As a result, it is possible to emit almost all the light in the range from the direction of the point p5 to the direction of the end point p1 of the reflecting surface Rl as parallel light without a lens. For this reason, since it can irradiate light to a narrow range when used as a light source for illumination, an instrument with high illumination efficiency can be realized. In addition, when used as a signal, when viewed from an observer in front of the optical system, the entire reflecting surface appears to emit light, and a high-intensity signal lamp can be realized.
[0078]
Further, since most of the light totally reflected on the lens surface can be emitted by one reflection by the reflecting surface, there is little loss of light due to repeated reflection, and the instrument efficiency is good. Moreover, since a convex lens is not comprised at all, a thin lighting fixture and a signal lamp can be realized, and manufacture is easy.
[0080]
  Claim2Then, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl, and there is no light beam that reaches the reflection surface Ru directly from the light source, so that the parallel light can be controlled more efficiently. Further, since the reflection surface Rl is closest to the light source, the solid angle when the reflection surface Rl is viewed from the light source is the largest, and a wider range of light flux can be controlled to parallel light.
[0081]
  Claims of the invention3According to the described LED module, since the lens surface LE covering the range of the point p5 from the light source is added, in this optical system, the light irradiated between the end point p1 and the point p5 ′ of the reflection surface Rl from the light source is The parallel light is controlled by a mechanism similar to that of the first aspect. In addition, the light irradiated in the direction of the lens surface LE is refracted in the direction of focusing on the axis c of the optical system and diffuses by reaching the lens surface because the lens surface LE forms a convex lens. The light that has been used can be collected. For this reason, when it is used as a light source for illumination, it is possible to irradiate light in a narrow range and does not leak much light to the periphery, so that an instrument with high illumination efficiency can be realized. In addition, when used as a signal light source, when viewed from an observer in front of the optical system, a signal lamp that emits light from the entire reflecting surface and has high brightness, and is not visible by an observer in other directions. realizable.
[0082]
Further, since most of the light totally reflected on the lens surface can be emitted by one reflection by the reflecting surface, there is little loss of light due to repeated reflection, and the instrument efficiency is good. In addition, since the lens shape is simple compared to the conventional example 2, it is easy to manufacture.
[0083]
  Claim 4Then, the light emitted from the light source between the end point p1 and the point p5 ′ of the reflection surface Rl is controlled to be parallel light by the same mechanism as in the first aspect. In addition, the light irradiated in the direction of the lens surface LE is controlled to be parallel light because the lens surface LE is an elliptical lens having the property of controlling light emitted from the focal point to parallel light. For this reason, light in a range from the axis c of the optical system to the direction of the end point p1 of the reflection surface Rl can be controlled to be almost parallel light and emitted.
[0085]
  Claim5Then, when viewed from the light source, the reflection surface Ru is hidden by the shadow of the reflection surface Rl and there is no light beam that reaches the reflection surface Ru directly from the light source, so that the light emitted from the light source can be more efficiently controlled to parallel light. Further, since the reflection surface Rl is closest to the light source, the solid angle when the reflection surface Rl is viewed from the light source is the largest, and a wider range of light flux can be controlled to parallel light.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a geometric configuration of an LED module according to a first embodiment of the present invention.
2A is an overall view of a signal lamp using the LED module according to the first embodiment of the present invention, FIG. 2B is an enlarged view of a lamp portion, and FIG. 2C is an AA ′ view of FIG. It is sectional drawing.
FIG. 3 is an operation explanatory diagram of the first embodiment of the present invention.
FIG. 4 (a) shows the present invention.Reference exampleThe whole figure of a downlight lighting fixture using the LED module of (b) is the AA 'sectional view.
FIG. 5 of the present inventionReference exampleIt is sectional drawing which shows the geometrical structure of LED module.
FIG. 6 shows the first aspect of the present invention.2The whole figure of the footlight lighting fixture using the LED module of embodiment of this, (b) is the AA 'sectional drawing.
FIG. 7 shows the first of the present invention.2It is sectional drawing which shows the geometric structure of the LED module of embodiment.
FIG. 8 (a) is the first of the present invention.3The whole line-of-sight guide light using the LED module of embodiment of this, (b) is the AA 'sectional drawing.
FIG. 9 shows the first aspect of the present invention.3It is sectional drawing which shows the geometric structure of the LED module of embodiment.
FIG. 10 shows the first of the present invention.3It is operation | movement explanatory drawing of this embodiment.
FIG. 11 (a) is the first of the present invention.4The whole LED module of embodiment of this, (b) is the AA 'sectional drawing.
FIG. 12 shows the first aspect of the present invention.4It is sectional drawing which shows the geometric structure of the LED module of embodiment.
FIG. 13 shows the first aspect of the present invention.4It is operation | movement explanatory drawing of this embodiment.
FIG. 14 (a) shows the present invention.Reference example(B) is an AA ′ sectional view of the LED module of FIG.
FIG. 15 shows the present invention.Reference exampleIt is sectional drawing which shows the geometrical structure of LED module.
FIG. 16 (a) is the first of the present invention.5The whole LED module of embodiment of this, (b) is the AA 'sectional drawing.
FIG. 17 shows the first of the present invention.5It is sectional drawing which shows the geometric structure of the LED module of embodiment.
18 is a cross-sectional view of an LED module of Conventional Example 1. FIG.
FIG. 19 is a cross-sectional view of an LED light source of Conventional Example 2.
[Explanation of symbols]
4 LED chips
5 Resin reflective frame
6 Aluminum deposition surface
7 Epoxy resin
c Optical system axis
Lp Lens surface
lp line segment
Rl reflecting surface
rl parabola
Ru reflecting surface
ru parabola
θ ′ critical angle

Claims

In an LED module including a light distribution unit which is surrounded by a reflective surface and is sealed with a sealing material, the LED light source disposed on the optical system axis c, and the lens surface Lp of the sealing material is connected to the optical system axis c. An inner reflecting surface Rl and an outer reflecting surface Ru, each of which is a concave curved surface, the reflecting surface being symmetrically arranged with respect to the axis c of the optical system.
A radial line segment lp along the lens surface Lp is a line segment on a straight line orthogonal to the axis c of the optical system,
The parabola rl in the radial direction along the inner reflection surface Rl has its focal point located at the point p0 on the light source, and the distance from one end point p1 of the parabola rl from the axis c of the optical system is necessary for the installation of the light source. The other end point p2 of the parabola rl is greater than or equal to the radius of the space, and the point p0 'is a point symmetrical to the point p0 on the light source with the line segment lp as the axis of symmetry, and the point p0 on the light source is the starting point. An intersection of a straight line extending at an angle of the critical angle θ ′ with respect to the axis c of the optical system and the line segment lp is p5, and a point on the straight line extending from the point p0 ′ and the point p5 to the light source side from the line segment lp. Yes,
The parabola ru in the radial direction along the outer reflective surface Ru has a focal point located at the point p0 ', and one end point p3 of the parabola ru is closer to the light source than a straight line extending between the points p0' and p5. The LED module is located outside the parabola rl, and the other end point p4 of the parabola ru is an intersection of the line segment lp and the parabola ru.

The distance from the axis c of the optical system at the end point p1 of the parabola rl is equal to the radius of the space necessary for installing the LED light source, and the distance from the axis c of the optical system at one end point p4 of the parabola ru 2. The LED module according to claim 1, wherein an intersection of a straight line extending from the point p0 and the end point p2 of the parabola rl and the line segment lp is defined as p4 ′ and the distance from the axis c of the optical system at the point p4 ′ is equal to or greater than the distance .

In an LED module including a light distribution portion that is surrounded by a reflecting surface and is sealed with a sealing material, the lens surface of the sealing material is centered on the axis c of the optical system. An inner lens surface LE made of a convex curved surface and an outer lens surface Lp made of a flat surface, and the inner reflective surface Rl made of a concave curved surface in which the reflecting surface is arranged symmetrically with respect to the axis c of the optical system. And the outer reflective surface Ru,
The radial curve lE along the inner lens surface LE is outside the straight line whose end point p5 'starts from the point p0 on the light source and extends at an angle of the critical angle θ' with respect to the axis c of the optical system,
A radial line segment lp along the outer lens surface Lp is a line segment on a straight line passing through the point p5 ′ and orthogonal to the axis c of the optical system,
The radial parabola rl along the inner reflection surface Rl has its focal point located at the point p0 on the light source, and the distance from one end point p1 of the parabola rl to the axis c of the optical system is the end point p5 ′ of the curve lE. The other end point p2 of the parabola rl is a point p0 ′ with a point symmetric with respect to the point p0 on the light source with the line segment lp as the axis of symmetry, p0 ′. Is located at the intersection of a straight line extending from the point p5 'and the parabola rl,
The radial parabola ru along the outer reflecting surface Ru has its focal point located at the point p0 ', and one end point p3 of the parabola ru is closer to the light source side than the straight line connecting the points p0' and p5 '. The LED module is located outside the parabola rl, and the other end point p4 of the parabola ru is an intersection of the line segment lp and the parabola ru .

A curve lE is a part of an ellipse, where the ratio of the major axis aE to the minor axis bE is nE is the refractive index of the lens medium and n is the refractive index of the air, bE / aE = (n ′ ² −n ² ) ^{1 / 2} / n ′, one focal point of the ellipse is located at the point p0 on the LED light source, the center of the ellipse is on the irradiation direction side of the point p0 on the axis c of the optical system, and the end point p5 ′ of the curve lE is 4. The LED module according to claim 3, wherein the LED module is an intersection of an ellipse and a short diameter bE thereof .

The distance from the optical system axis c of one end point p1 of the parabola rl is equal to the distance from the optical system axis c of the end point p5 'of the curve lE, and from the optical system axis c of the one end point p4 of the parabola ru. 5 is equal to or greater than the distance from the axis c of the optical system of p4 ′, where p4 ′ is an intersection of a straight line extending from the point p0 on the LED light source and the end point p2 of the parabola rl and the line segment lp. The LED module described .