JP3788685B2

JP3788685B2 - Water drop detection sensor with transmission / reception function

Info

Publication number: JP3788685B2
Application number: JP09180198A
Authority: JP
Inventors: 修平田中
Original assignee: Niles Co Ltd
Current assignee: Niles Co Ltd
Priority date: 1998-04-03
Filing date: 1998-04-03
Publication date: 2006-06-21
Anticipated expiration: 2018-04-03
Also published as: JPH11287752A

Description

【０００１】
【発明の属する技術分野】
本発明は、自動車用ウインドガラスに付着する水滴を検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサに関する。
【０００２】
【従来の技術】
自動車のフロントガラスに雨滴が付着したことを検知して、ワイパーを自動的に動作させる試みが従来から行なわれており、このような検知機能を備えた基板として、図７に示す構造のものがある。
【０００３】
即ち、ガラス板等の透明基板１００の表面にプリズム１０１，１０２を貼着し、プリズム１０１を介して光源１０３からの光を全反射する角度で透明基板１００内に導入する。そして、水などの液体が透明基板１００の表面に存在すると全反射が起こらないように入射角度を設定しておくと、ガラス表面の全反射点における液体の有無により全反射の光量が変化するので、この変化量を受光素子１０４などにより検知することにより、液体の存在を知ることができるというものである。
【０００４】
そして、特開昭６０−２１６２４５号公報には、上記の検知方式のように、光源からの光をガラス板面で全反射させ、これをプリズムを介して受光素子に入射させていたのでは、検知感度が悪いので、ガラス面に水滴が付着した時にのみ、当該水滴からの反射光を受光素子に入射するようにプリズムの角度を設定した内容が開示されている。
【０００５】
また、特開昭６２−１６３９４９号公報には、２つの光源を用意し、一方の光源からの光束の検出面における入射角を全反射の臨界角以上とし、他方の光源からの光束の検出面における入射角を全反射の臨界角以下とし、水以外の付着物との識別ができるようにした構成が開示されている。
【０００６】
更に、特開平８−２６１９７４号公報には、ガラス板の内部に櫛形の透明電極を配置し、ガラス板表面に水滴が付着したことによって生じる櫛形の透明電極間の静電容量の変化を検出し、これに応じて窓の開閉やヒータの制御を行なうようにした構成が開示されている。
【０００７】
また、特表平６−５０９６５２号公報には、ウインドシールドの外側表面の水滴を検知し、水滴に対応してウインドシールド用ワイパの動作を制御するために、ウインドシールドの内側表面に、プリズムなどからなる感知ユニットを２つの粘着性の面を備えた中間層で接着した構成が開示されている。
【０００８】
【発明が解決しようとする課題】
従来の光学式検知機能を備えた透明基板にあっては、ガラス中に全反射光を導入するためにプリズムが必須要件であると共に、このプリズムをガラス面に密着させる必要があり、取付作業に手間がかかる。特に、自動車のウインドシールドガラスなどは湾曲したデザインが多く採用されており、密着させることが困難である。
また、プリズムとガラス表面との界面での不要な反射をさけるために、屈折率をできるだけ近づける必要がある（屈折率マッチング）。このためにマッチング層を設けることも考えられるが、工程が増加し、コスト面で不利が生じる。
【０００９】
一方、特開平８−２６１９７４号公報のように、電極間の電気抵抗の変化、電気容量の変化などを検知して行う方式は、耐久性、感度の面で光学式に劣り、特に自動車用のフロントガラスにあっては、運転者あるいは同乗者の視認性に追随した信号であることが重要であり、光学式のセンサが望ましい。
【００１０】
本発明は、従来の技術が有するこのような問題点に鑑みてなされたものであり、その目的とするところは、プリズムが不要で、且つ構造が簡単で、自動車用ウインドガラスに付着した水滴を確実に検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサを提供しようとするものである。
【００１１】
【課題を解決するための手段】
上記課題を解決すべく請求項１に係る発明は、検出用光の反射光量の変化でウインドガラスに付着した水滴を検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサであって、前記検出用光を前記ウインドガラスに入射させる発光手段と前記検出用光のうち前記ウインドガラス内を全反射した光を検出する受光手段を前記ウインドガラスの室内側面に設けると共に、外部と送受信する送受信手段を前記検出用光の反射点部を避けた前記ウインドガラスの室内側面に設けたものである。
【００１２】
請求項２に係る発明は、検出用光の反射光量の変化で中間膜を有するウインドガラスに付着した水滴を検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサであって、前記検出用光を前記ウインドガラスに入射させる発光手段と前記検出用光のうち前記ウインドガラス内を全反射した光を検出する受光手段を前記ウインドガラスの室内側面に設けると共に、外部と送受信する送受信手段を前記検出用光の反射点部を避けた前記ウインドガラスの室内側面に設け、前記中間膜のうち前記受光手段に対向する部分を反射膜としたものである。
【００１３】
請求項３に係る発明は、検出用光の反射光量の変化で中間膜を有するウインドガラスに付着した水滴を検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサであって、前記検出用光を前記ウインドガラスに入射させる発光手段と前記検出用光のうち前記ウインドガラス内を全反射した光を検出する受光手段を前記ウインドガラスの室内側面であって黒色セラミックスの不塗布部に設けると共に、前記検出用光の反射点部を黒色セラミックスの不塗布部とし、この不塗布部に空気層を介して外部と送受信する送受信手段を設けたものである。
【００１４】
請求項４に係る発明は、検出用光の反射光量の変化で中間膜を有するウインドガラスに付着した水滴を検出すると共に、外部と送受信を行う送受信機能付き水滴検出センサであって、前記検出用光を前記ウインドガラスに入射させる発光手段と前記検出用光のうち前記ウインドガラス内を全反射した光を検出する受光手段を前記ウインドガラスの室内側面であって黒色セラミックスの不塗布部に設け、前記検出用光の反射点部を黒色セラミックスの不塗布部とすると共に、外部と送受信する送受信手段を前記反射点部を避けた黒色セラミックスの不塗布部に設けたものである。
【００１５】
請求項５に係る発明は、請求項１、２、３又は４記載の送受信機能付き水滴検出センサにおいて、前記送受信手段を光で送受信を行う光送受信手段としたものである。
【００１６】
請求項６に係る発明は、請求項１、２、３又は４記載の送受信機能付き水滴検出センサにおいて、前記送受信手段を音波で送受信を行う音波送受信手段としたものである。
【００１７】
【発明の実施の形態】
以下に本発明の実施の形態を添付図面に基づいて説明する。ここで、図１は本発明に係る送受信機能付き水滴検出センサを装着した自動車前部の斜視図、図２は本発明の第１の実施の形態に係る送受信機能付き水滴検出センサの構成説明図、図３は本発明に係る送受信機能付き水滴検出センサをワイパ制御と自動料金収受システムに適用した構成図、図４乃至図６は本発明の第２乃至第４の実施の形態に係る送受信機能付き水滴検出センサの構成説明図である。
【００１８】
図１に示すように、送受信機能付き水滴検出センサ１，…は、自動車のウインドシールド２の室内側面であって、外側面を払拭するワイパ３の払拭領域に対向する部位に接着部材４で取付けられている。
なお、ウインドシールド２には、ＳｉＯ₂を主成分とする５ｍｍ厚のソーダライムガラス基板を用いている。
【００１９】
本発明の第１の実施の形態に係る送受信機能付き水滴検出センサ１は、図２に示すように、検出用光を出射する発光手段５と、その検出用光を検出する受光手段６と、外部と光で情報の送受信を行う光送受信手段９を備えている。そして、発光手段５と受光手段６は、ウインドシールド２の室内側面で所定の間隔を設け、ともに発光面５ａ又は受光面６ａをウインドシールド２に対向させて接着部材４で固定されている。
なお、送受信手段として光で送受信を行う光送受信手段９としたが、音波で送受信を行う音波送受信手段とすることもできる。
【００２０】
所定の間隔を設けて発光手段５と受光手段６をウインドシールド２の室内側面に固定するのは、発光手段５から受光手段６に至る光路長をなるべく短くして発光手段５から出射した検出用光の損失を所定レベル以下に維持しつつ、所定の検出面積（全反射点数）をウインドシールド２の外側面に確保するためである。
【００２１】
また、光送受信手段９は、発光手段５と受光手段６の間で、発光手段５と受光手段６を結ぶ線上又はその線上を外した近傍に、受光手段６と同様に送受信面９ａをウインドシールド２に対向させて接着部材４で固定されている。
【００２２】
接着部材４としては、エポキシ接着部材や紫外線硬化性のエポキシ接着部材など、ウインドシールド２の屈折率（１．４８）とほぼ等しい屈折率を有するものを選定している。また、発光手段５及び受光手段６をシリコン系透明接着シートでウインドシールド２の室内側面に固着させた後に、接着部材４に発光手段５及び受光手段６を埋設するように固定することもできる。
【００２３】
また、発光手段５及び受光手段６をウインドシールド２に固定するために盛った接着部材４を覆う遮光部材７，８を設けている。
遮光部材７，８は、接着部材４を光学的に遮蔽するための樹脂であり、一方の遮光部材７は発光手段５から不要な方向に光が漏れるのを防ぐ役割を果たし、他方の遮光部材８は外部光などが直接受光手段６に入るのを防ぐ役割を果たす。
従って、発光手段５から洩れる光がウインドシールド２の内部を伝播せずに、直接受光手段６に入ることはない。
【００２４】
また、遮光部材７，８の接着部材４との接触面、即ち発光手段５及び受光手段６と対向する遮光部材７，８の面に反射性能を持たせるとよい。
また、遮光部材７，８の接着部材４との接触面、即ち発光手段５及び受光手段６と対向する遮光部材７，８の面を凹鏡面に形成することもできる。
【００２５】
このように遮光部材７，８の接着部材４との接触面に反射性能を持たせたり、接触面を凹鏡面に形成することにより、発光手段５から後方に出射した光を集めてウインドシールド２の方向へ進ませて検出用光として利用できる。更に、ウインドシールド２の内部を伝播してきたものの受光手段６に直接入射できなかった検出用光を遮光部材８に反射させて受光手段６に入射させることもでき、光の有効利用が図れる。
【００２６】
発光手段５は、図３に示すように、発光ダイオード（ＬＥＤ）やレーザダイオード（ＬＤ）などの発光素子１０と、発光素子１０から所定周波数で変調した光を出力させる駆動回路１１と、発光素子１０の出力レベルをモニタするフォトダイオード（ＰＤ）などの受光素子１２と、受光素子１２の出力信号から変調成分に対応する信号を取り出し駆動回路１１にフィードバックする検出回路１３などからなる。駆動回路１１では、検出回路１３の出力信号が所望の出力レベルを維持するように発光素子１０に流す駆動電流を制御している。
【００２７】
受光手段６は、図３に示すように、検出用光及び外部光を電気信号に変換するＰＤなどの受光素子１４と、受光素子１４の出力信号から発光素子１０の駆動回路１１による変調成分に対応する信号を取り出す検出回路１５と、検出回路１５の出力信号を増幅や演算処理する増幅回路１６を備えている。
そして、増幅回路１６の出力信号は、ワイパ駆動部１９へ入力されてワイパ制御に使用される。
【００２８】
光送受信手段９は、発光素子、受光素子及び変復調回路などからなり、車載機器２０に接続されている。光送受信手段９と車載機器２０は、自動料金収受システムなどに使用され、例えば高速道路側に設置された光ビーコン（入口ビーコン、予告ビーコン、料金所ビーコンなど）と光通信を行い、高速道路の入口及び出口料金所情報、車種情報などの情報交換を通して料金収受処理を行う。
【００２９】
なお、発光手段５を、発光素子１０のみで、又は発光素子１０とモニタ用の受光素子１２で構成し、駆動回路１１や検出回路１３などを別の場所に配置してもよい。また、受光手段６を、受光素子１４のみで構成し、検出回路１５や増幅回路１６などを別の場所に配置してもよい。また、光送受信手段９を、発光素子と受光素子のみで構成し、変復調回路などを別の場所に配置してもよい。
【００３０】
以上のように構成した送受信機能付き水滴検出センサ１の作用について説明する。
発光手段５から出射した光は、発光素子１０がＬＥＤの場合には、ほぼ四方八方に放射され、発光素子１０がＬＤの場合には、ほぼ一方向に放射される。
これらの光は、接着部材４を通してウインドシールド２の内部に入る。接着部材４として、ウインドシールド２の屈折率とほぼ等しい屈折率のものを選定したので、発光手段５から出射した光は接着部材４とウインドシールド２との界面で屈折することなく直進する。
【００３１】
そして、図２に示すように、ウインドシールド２の内部に臨界角未満の入射角で入った光は、ウインドシールド２を通過して外部に抜ける。
一方、ウインドシールド２の内部に臨界角以上の入射角で入った光は、ウインドシールド２の外側面と空気との界面及びウインドシールド２の室内側面と空気との界面を交互に全反射しながらウインドシールド２の内部を伝播する。
そして、ウインドシールド２の内部で全反射した光は、受光手段６に入射する。
【００３２】
ここで、空気とガラスとの界面で全反射が始まるときの入射角、即ち臨界角を求めるには、スネルの法則を用いて以下の計算を行う。
スネルの法則の一般式は、以下に示す数式（１）のようになる。但し、α及びα₀は、屈折率ｎの物質と屈折率ｎ₀の物質との界面の法線に対する角度である（α：入射角、α₀：屈折角）。
【００３３】
ｎ₀・ｓｉｎα₀＝ｎ・ｓｉｎα （１）
【００３４】
ガラスの屈折率ｎをｎ＝１．４８とし、空気の屈折率ｎ₀をｎ₀＝１とした場合、空気とガラスとの界面であってガラス内部で全反射するための入射角αの条件は、屈折角α₀が、α₀≧９０°となればよいので、その時の入射角αは、数式（１）より、α≧４２．５°となる。
従って、入射角αが、臨界角（４２．５°）以上であれば、ガラス媒質中での全反射が起こる。
【００３５】
一方、水がガラス面に付着した場合でも、水とガラスとの界面であってガラス内部で全反射するための入射角αの条件は、水の屈折率をｎ₀＝１．３３として、同様の計算を行うと、α≧６４．０°となる。
従って、入射角αが、臨界角（６４．０°）以上であれば、ガラス媒質中での全反射が起こる。
【００３６】
従って、入射角αが、４２．５°から６４．０°の範囲（４２．５°≦α≦６４．０°）であれば、水がガラスに付着してないときはガラス内部で全反射し、水が付着すると全反射しなくなり、光はガラス内部から水を介して外部に洩れることになる。
【００３７】
このような反射を起こさせるために、発光手段５を固着する位置を調整して入射角αの条件（４２．５°≦α≦６４．０°）を満たすように、発光手段５から出射する光の入射角を設定した。また、受光手段６に反射光が入る入射角も発光手段５の場合と対称の関係になるので、反射光を漏れなく受光するように受光手段６を固着する位置を調整した。
【００３８】
従って、ウインドシールド２の外側面又は室内側面のいずれか又は両面に水滴Ｗが付着している場合には、伝播途中の光は水滴Ｗを通してウインドシールド２の外部に抜けてしまい、受光手段６に到達する光量が減少する。
そこで、この光量の減少分を検出回路１５で検出し、増幅回路１６で演算処理すると、水滴Ｗの付着の程度が分かる。
【００３９】
本発明では、入射角αの条件（４２．５°≦α≦６４．０°）を満たす範囲で入射する光を全て利用するため、ウインドシールド２の面に付着する水滴Ｗを離散的な光の反射点ではなく、多数の反射点の集合である面に付着する水滴Ｗを検出するので、離散的な反射点に付着する水滴Ｗを検出する場合に比べ、ウインドシールド２の面に付着する水滴Ｗの検出確度が向上する。
【００４０】
そして、図３に示すように、受光手段６は、水滴Ｗの付着量に相当する出力信号を、ワイパ駆動部１９へ入力する。
すると、ワイパ駆動部１９では、検出された水滴Ｗの付着量が設定値以上の場合には、水滴Ｗの付着量に応じた間隔でワイパ３を作動状態にし、一方検出された水滴Ｗの付着量が設定値未満になった場合には、ワイパ３を停止状態にする。
【００４１】
また、自動車が有料道路を利用する場合には、光送受信手段９が、高速道路側に設置された光ビーコン（入口ビーコン、予告ビーコン、料金所ビーコンなど）と光通信を行い、入口及び出口料金所情報、車種情報などの情報交換を通して車載機器２０と共に料金収受処理を行う。
【００４２】
図４に示すように、本発明の第２の実施の形態に係る送受信機能付き水滴検出センサ２１は、中間膜２２を有するウインドシールド２に発光手段５と受光手段６と光送受信手段９を固着し、中間膜２２のうち発光手段５の発光面５ａ及び受光手段６の受光面６ａと対向する部分を反射膜２３，２４とした。
なお、送受信手段として光で送受信を行う光送受信手段９としたが、音波で送受信を行う音波送受信手段とすることもできる。他の構成については、図２に示す送受信機能付き水滴検出センサ１と同様である。
【００４３】
一方の反射膜２３は、発光手段５から出射した光のうちウインドシールド２の内部を全反射しない光が外部に洩れるのを防ぐために設けられている。
他方の反射膜２４は、ウインドシールド２の内部を全反射してくる光が受光手段６に入射するのを遮らない範囲で、外部光が必要以上受光手段６に入射するのを防ぐために設けられている。
【００４４】
以上のように構成した送受信機能付き水滴検出センサ２１の作用については、中間膜２２の一部を反射膜２３，２４としたこと以外は、図２に示す水滴及び光量検出センサ１と同様である。
【００４５】
図５に示すように、本発明の第３の実施の形態に係る送受信機能付き水滴検出センサ３１は、ウインドシールド２の室内側面の周辺部に、黒色セラミックス３２が帯状に塗布され、そのなかに黒色セラミックス３２の不塗布部３２ａが形成され、それらの不塗布部３２ａに発光手段５と受光手段６が接着部材４で固定されている。
【００４６】
また、発光手段５から出射する検出用光が全反射するウインドシールド２の室内側面の各部も、ウインドシールド２の外側面と同様に空気との界面を形成して同一条件で全反射するようにするため、黒色セラミックス３２の不塗布部３２ａが形成されている。
【００４７】
そして、不塗布部３２ａの一箇所には、空気層３３を介して光送受信手段９が、その送受信面９ａをウインドシールド２の室内側面に対向させて接着部材４で固定されている。空気層３３は、ウインドシールド２の外側面と同じ全反射の条件にするために設けるものである。
なお、送受信手段として光で送受信を行う光送受信手段９としたが、音波で送受信を行う音波送受信手段とすることもできる。
【００４８】
更に、発光手段５と受光手段６と光送受信手段９は、ガラス、樹脂、セラミックス又は金属製のケース３４により覆われている。ケース３４は、シール部材としても機能する接着部材３５により黒色セラミックス３２に固定され、ケース３４とウインドシールド２で密閉空間を形成している。
【００４９】
また、ウインドシールド２の室内側面と光送受信手段９との間に形成される空気層３３には、反射点である黒色セラミックス３２の不塗布部３２ａにおける結露を防止するため、モレキューラーシーブ等の脱水剤又は乾燥空気が封入されている。更に、ケース３４とウインドシールド２で形成される密閉空間には、モレキューラーシーブ等の脱水剤３６又は乾燥空気が封入されている。
なお、その他の構成については、図４に示す送受信機能付き水滴検出センサ２１と同様である。
【００５０】
ケース３４が固定される黒色セラミックス３２が塗布される場所は、室内ミラーを取り付ける場所でもあり、室内ミラーの取付ベースとケース３４を共用化することにより、省取付スペース化が図れる。
なお、ケース３４の黒色セラミックス３２への固定方法は、上述の接着機能を有するシール部材３５で固着する他に、黒色セラミックス３２に止め材を接着剤で固着した後に、ケース３４に形成したフランジ部をねじで止め材に固定することもできる。
【００５１】
以上のように構成した送受信機能付き水滴検出センサ３１の作用については、ウインドシールド２の室内側面の周辺部であって、黒色セラミックス３２が帯状に塗布される部分に発光手段５と受光手段６と光送受信手段９を固定することによる作用以外は、図４に示す送受信機能付き水滴検出センサ２１と同様である。
【００５２】
図６に示すように、本発明の第４の実施の形態に係る送受信機能付き水滴検出センサ４１は、光送受信手段９を検出用光が全反射するウインドシールド２の室内側面の各部を避けて黒色セラミックス３２の不塗布部３２ａに接着部材４で固着した以外は、図５に示す送受信機能付き水滴検出センサ３１と構成が同様である。
なお、送受信手段として光で送受信を行う光送受信手段９としたが、音波で送受信を行う音波送受信手段とすることもできる。
【００５３】
検出用光が全反射するウインドシールド２の室内側面の各部を避けて光送受信手段９を設けることにより、外側面と同じ全反射の条件にするための空気層３３を形成する必要がなく、更に発光手段５や受光手段６と同様に、ウインドシールド２の室内側面に直接光送受信手段９を固着することができる。
【００５４】
以上のように構成した送受信機能付き水滴検出センサ４１の作用については、光送受信手段９を検出用光が全反射するウインドシールド２の室内側面の各部を避けたことによる作用以外は、図５に示す送受信機能付き水滴検出センサ３１と同様である。
【００５５】
【発明の効果】
以上説明したように請求項１に係る発明によれば、プリズムが不要且つ構造が簡単になる。また、離散的な光の反射点ではなく、多数の反射点の集合である面に付着する水滴を検出するので、離散的な反射点に付着する水滴のみ検出する場合に比べ、検出確度が向上する。
更に、車外と送受信ができる送受信手段を設けたので、センサとしての応用範囲が広がる。
【００５６】
請求項２に係る発明によれば、中間膜のうち発光手段の発光面及び受光手段の受光面と対向する部分を反射膜としたので、発光手段から出射した光のうちウインドガラスの内部を全反射しない光が外部に洩れるのを防ぎ、且つ外部光が受光手段に入射するのを防ぐことができる。
また、車外と送受信ができる送受信手段を設けたことにより、センサとしての応用範囲が広がる。
【００５７】
請求項３に係る発明によれば、ウインドガラスの室内側面の周辺部であって、黒色セラミックスが帯状に塗布される部分に発光手段と受光手段と光ビーコン送受信手段を固定するので、室内ミラーの取付ベースなどと取付スペースを共用化でき、省取付スペース化に寄与できる。
また、車外と送受信ができる送受信手段を設けたことにより、センサとしての応用範囲が広がる。
【００５８】
請求項４に係る発明によれば、送受信手段を検出用光が全反射するウインドガラスの室内側面の各部を避けて固定するので、ウインドガラスの室内側面に空気層を介することなく、直接固着することができ、取付けが容易となる。
また、車外と送受信ができる送受信手段を設けたことにより、センサとしての応用範囲が広がる。
【００５９】
請求項５に係る発明によれば、送受信手段を、光で送受信を行う光送受信手段としたことにより、センサとしての応用範囲が広がる。
【００６０】
請求項６に係る発明によれば、送受信手段を、音波で送受信を行う音波送受信手段としたことにより、センサとしての応用範囲が広がる。
【図面の簡単な説明】
【図１】本発明に係る送受信機能付き水滴検出センサを装着した自動車前部の斜視図
【図２】本発明の第１の実施の形態に係る送受信機能付き水滴検出センサの構成説明図
【図３】本発明に係る送受信機能付き水滴検出センサをワイパ制御と自動料金収受システムに適用した構成図
【図４】本発明の第２の実施の形態に係る送受信機能付き水滴検出センサの構成説明図
【図５】本発明の第３の実施の形態に係る送受信機能付き水滴検出センサの構成説明図で、（ａ）は断面図、（ｂ）は背面図
【図６】本発明の第４の実施の形態に係る送受信機能付き水滴検出センサの構成説明図で、（ａ）は断面図、（ｂ）は背面図
【図７】従来の水滴検出センサの構成図
【符号の説明】
１，２１，３１，４１…送受信機能付き水滴検出センサ、２…ウインドシールド（ウインドガラス）、３…ワイパ、４…接着部材、５…発光手段、５ａ…発光面、６…受光手段、６ａ…受光面、７，８…遮光部材、９…光送受信手段、９ａ…送受信面、２２…中間膜、２３，２４…反射膜、３２…黒色セラミックス、３２ａ…黒色セラミックスの不塗布部、３３…空気層、３４…ケース、Ｗ…水滴。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water droplet detection sensor with a transmission / reception function that detects water droplets adhering to an automobile window glass and performs transmission / reception with the outside.
[0002]
[Prior art]
Attempts have been made to automatically operate the wiper by detecting that raindrops have adhered to the windshield of an automobile. A substrate having such a detection function has a structure shown in FIG. is there.
[0003]
That is, the prisms 101 and 102 are attached to the surface of the transparent substrate 100 such as a glass plate, and the light from the light source 103 is introduced into the transparent substrate 100 through the prism 101 at an angle at which the light is totally reflected. If the incident angle is set so that total reflection does not occur when a liquid such as water is present on the surface of the transparent substrate 100, the amount of total reflection changes depending on the presence or absence of liquid at the total reflection point on the glass surface. By detecting this change amount by the light receiving element 104 or the like, the presence of the liquid can be known.
[0004]
In JP-A-60-216245, as in the detection method described above, the light from the light source is totally reflected on the glass plate surface and is incident on the light receiving element via the prism. Since the detection sensitivity is poor, there is disclosed a content in which the angle of the prism is set so that the reflected light from the water droplet enters the light receiving element only when the water droplet adheres to the glass surface.
[0005]
Japanese Patent Application Laid-Open No. 62-163949 provides two light sources, the incident angle on the detection surface of the light beam from one light source is set to be equal to or greater than the critical angle of total reflection, and the detection surface of the light beam from the other light source. An arrangement is disclosed in which the incident angle at is less than the critical angle of total reflection so that it can be distinguished from deposits other than water.
[0006]
Further, in Japanese Patent Laid-Open No. 8-261974, a comb-shaped transparent electrode is disposed inside a glass plate, and a change in capacitance between the comb-shaped transparent electrodes caused by water droplets adhering to the glass plate surface is detected. In response to this, a configuration is disclosed in which the opening and closing of the window and the control of the heater are performed.
[0007]
Also, Japanese Patent Publication No. 6-509652 discloses a prism or the like on the inner surface of the windshield in order to detect water drops on the outer surface of the windshield and control the operation of the windshield wiper in response to the water drops. A structure is disclosed in which a sensing unit consisting of is bonded with an intermediate layer having two sticky surfaces.
[0008]
[Problems to be solved by the invention]
In the case of a transparent substrate having a conventional optical detection function, a prism is an essential requirement for introducing totally reflected light into the glass, and it is necessary to make this prism adhere to the glass surface. It takes time and effort. In particular, windshield glass for automobiles has many curved designs and is difficult to adhere.
Moreover, in order to avoid unnecessary reflection at the interface between the prism and the glass surface, it is necessary to make the refractive index as close as possible (refractive index matching). For this reason, it is conceivable to provide a matching layer, but the number of processes increases, resulting in a disadvantage in cost.
[0009]
On the other hand, as disclosed in Japanese Patent Application Laid-Open No. 8-261974, a method for detecting changes in electrical resistance between electrodes, changes in capacitance, etc. is inferior to an optical method in terms of durability and sensitivity, and particularly for automobiles. In the windshield, it is important that the signal follows the driver's or passenger's visibility, and an optical sensor is desirable.
[0010]
The present invention has been made in view of such problems of the prior art, and the object of the present invention is to eliminate the need for a prism, a simple structure, and water droplets adhering to an automotive window glass. An object of the present invention is to provide a water drop detection sensor with a transmission / reception function for reliably detecting and transmitting / receiving to / from the outside.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is a water droplet detection sensor with a transmission / reception function that detects a water droplet attached to the window glass by a change in the amount of reflected light of the detection light and transmits / receives to / from the outside, A light emitting means for making detection light incident on the window glass and a light receiving means for detecting light totally reflected in the window glass out of the detection light are provided on the indoor side surface of the window glass, and transmission / reception means for transmitting and receiving to the outside Is provided on the indoor side surface of the window glass while avoiding the reflection point portion of the detection light.
[0012]
The invention according to claim 2 is a water droplet detection sensor with a transmission / reception function for detecting water droplets attached to a window glass having an intermediate film by a change in reflected light amount of detection light and transmitting / receiving to / from the outside. A light emitting means for making light incident on the window glass and a light receiving means for detecting light totally reflected in the window glass out of the detection light are provided on the indoor side surface of the window glass, and a transmission / reception means for transmitting / receiving to / from the outside is provided. It is provided on the indoor side surface of the window glass that avoids the reflection point portion of the detection light, and the portion of the intermediate film that faces the light receiving means is a reflective film.
[0013]
The invention according to claim 3 is a water droplet detection sensor with a transmission / reception function for detecting water droplets attached to the window glass having an intermediate film by a change in the amount of reflected light of detection light and transmitting / receiving to / from the outside. A light emitting means for making light incident on the window glass and a light receiving means for detecting light that has been totally reflected in the window glass out of the detection light are provided on the interior side surface of the window glass on an uncoated portion of the black ceramic. The reflection point portion of the detection light is an uncoated portion of black ceramics, and transmitting / receiving means for transmitting / receiving to / from the outside through an air layer is provided on the uncoated portion.
[0014]
The invention according to claim 4 is a water droplet detection sensor with a transmission / reception function for detecting water droplets adhering to the window glass having an intermediate film by a change in the amount of reflected light of the detection light and transmitting / receiving to / from the outside. A light emitting means for making light incident on the window glass and a light receiving means for detecting light totally reflected in the window glass out of the detection light are provided on a non-coated portion of the black ceramic on the indoor side surface of the window glass; The reflection point portion of the detection light is an uncoated portion of black ceramics, and transmitting / receiving means for transmitting / receiving to / from the outside is provided in the uncoated portion of black ceramics avoiding the reflection point portion.
[0015]
According to a fifth aspect of the present invention, in the water drop detection sensor with a transmission / reception function according to the first, second, third, or fourth aspect, the transmission / reception means is an optical transmission / reception means for transmitting / receiving light.
[0016]
According to a sixth aspect of the present invention, in the water drop detection sensor with a transmission / reception function according to the first, second, third, or fourth aspect, the transmission / reception means is a sound wave transmission / reception means for transmitting / receiving sound waves.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a perspective view of a front part of a vehicle equipped with a water drop detection sensor with a transmission / reception function according to the present invention, and FIG. 2 is an explanatory diagram of the configuration of the water drop detection sensor with a transmission / reception function according to the first embodiment of the present invention. FIG. 3 is a configuration diagram in which a water droplet detection sensor with a transmission / reception function according to the present invention is applied to a wiper control and an automatic toll collection system, and FIGS. 4 to 6 are transmission / reception functions according to second to fourth embodiments of the present invention. It is a configuration explanatory view of the attached water droplet detection sensor.
[0018]
As shown in FIG. 1, the water drop detection sensors 1 with transmission / reception functions are attached to the interior side surface of the windshield 2 of the automobile by an adhesive member 4 at a position facing the wiping area of the wiper 3 for wiping the outer side surface. It has been.
The windshield 2 uses a 5 mm thick soda lime glass substrate mainly composed of SiO ₂ .
[0019]
As shown in FIG. 2, the water drop detection sensor 1 with a transmission / reception function according to the first embodiment of the present invention includes a light emitting means 5 for emitting detection light, a light receiving means 6 for detecting the detection light, Optical transmission / reception means 9 for transmitting / receiving information to / from the outside by light is provided. The light emitting means 5 and the light receiving means 6 are fixed by an adhesive member 4 with a predetermined interval provided on the indoor side surface of the windshield 2 and with the light emitting surface 5 a or the light receiving surface 6 a facing the windshield 2.
In addition, although it was set as the optical transmission / reception means 9 which transmits / receives with light as a transmission / reception means, it can also be set as the sound wave transmission / reception means which transmits / receives with a sound wave.
[0020]
The reason why the light emitting means 5 and the light receiving means 6 are fixed to the interior side surface of the windshield 2 with a predetermined interval is to detect the light emitted from the light emitting means 5 by shortening the optical path length from the light emitting means 5 to the light receiving means 6 as much as possible. This is because a predetermined detection area (total number of reflection points) is secured on the outer surface of the windshield 2 while maintaining the light loss below a predetermined level.
[0021]
Further, the optical transmission / reception means 9 windshields the transmission / reception surface 9a between the light emission means 5 and the light reception means 6 on the line connecting the light emission means 5 and the light reception means 6 or in the vicinity where the line is removed. 2 and fixed by an adhesive member 4.
[0022]
As the adhesive member 4, an adhesive member having a refractive index substantially equal to the refractive index (1.48) of the windshield 2 such as an epoxy adhesive member or an ultraviolet curable epoxy adhesive member is selected. Alternatively, the light emitting means 5 and the light receiving means 6 may be fixed to the adhesive member 4 so that the light emitting means 5 and the light receiving means 6 are buried after the light emitting means 5 and the light receiving means 6 are fixed to the indoor side surface of the windshield 2 with a silicon-based transparent adhesive sheet.
[0023]
Further, light-shielding members 7 and 8 are provided to cover the adhesive member 4 that is stacked to fix the light-emitting means 5 and the light-receiving means 6 to the windshield 2.
The light shielding members 7 and 8 are resins for optically shielding the adhesive member 4. One light shielding member 7 serves to prevent light from leaking from the light emitting means 5 in an unnecessary direction, and the other light shielding member. 8 serves to prevent external light or the like from directly entering the light receiving means 6.
Therefore, light leaking from the light emitting means 5 does not propagate through the windshield 2 and does not enter the light receiving means 6 directly.
[0024]
Further, the contact surfaces of the light shielding members 7 and 8 with the adhesive member 4, that is, the surfaces of the light shielding members 7 and 8 facing the light emitting means 5 and the light receiving means 6 may be provided with reflection performance.
In addition, the contact surfaces of the light shielding members 7 and 8 with the adhesive member 4, that is, the surfaces of the light shielding members 7 and 8 facing the light emitting means 5 and the light receiving means 6 can be formed as concave mirror surfaces.
[0025]
In this way, the light shielding members 7 and 8 are provided with reflective performance on the contact surfaces of the light shielding members 7 and 8 or the contact surfaces are formed as concave mirror surfaces, thereby collecting the light emitted rearward from the light emitting means 5 and the windshield 2. It can be used as detection light. Furthermore, the detection light that has propagated through the inside of the windshield 2 but could not be directly incident on the light receiving means 6 can be reflected by the light shielding member 8 and incident on the light receiving means 6, so that the light can be used effectively.
[0026]
As shown in FIG. 3, the light emitting means 5 includes a light emitting element 10 such as a light emitting diode (LED) or a laser diode (LD), a drive circuit 11 for outputting light modulated at a predetermined frequency from the light emitting element 10, and a light emitting element. 10 includes a light receiving element 12 such as a photodiode (PD) for monitoring the output level, a detection circuit 13 for extracting a signal corresponding to the modulation component from the output signal of the light receiving element 12 and feeding it back to the drive circuit 11. In the drive circuit 11, the drive current that flows to the light emitting element 10 is controlled so that the output signal of the detection circuit 13 maintains a desired output level.
[0027]
As shown in FIG. 3, the light receiving means 6 includes a light receiving element 14 such as a PD that converts detection light and external light into an electrical signal, and converts the output signal of the light receiving element 14 into a modulation component by the drive circuit 11 of the light emitting element 10. A detection circuit 15 for extracting a corresponding signal, and an amplification circuit 16 for amplifying and calculating the output signal of the detection circuit 15 are provided.
The output signal of the amplifier circuit 16 is input to the wiper driving unit 19 and used for wiper control.
[0028]
The optical transmission / reception means 9 includes a light emitting element, a light receiving element, a modulation / demodulation circuit, and the like, and is connected to the in-vehicle device 20. The optical transmission / reception means 9 and the in-vehicle device 20 are used in an automatic toll collection system, and perform optical communication with, for example, an optical beacon (an entrance beacon, a warning beacon, a toll gate beacon, etc.) installed on the highway side, Toll collection processing is performed through information exchange such as entrance and exit tollgate information and vehicle type information.
[0029]
Note that the light emitting means 5 may be composed of only the light emitting element 10 or the light emitting element 10 and the light receiving element 12 for monitoring, and the drive circuit 11 and the detection circuit 13 may be arranged in another place. Further, the light receiving means 6 may be constituted by only the light receiving element 14, and the detection circuit 15, the amplifier circuit 16 and the like may be arranged in another place. Further, the optical transmission / reception means 9 may be constituted by only a light emitting element and a light receiving element, and a modulation / demodulation circuit or the like may be arranged at another place.
[0030]
The operation of the water droplet detection sensor 1 with a transmission / reception function configured as described above will be described.
The light emitted from the light emitting means 5 is emitted in almost all directions when the light emitting element 10 is an LED, and is emitted in almost one direction when the light emitting element 10 is an LD.
These lights enter the inside of the windshield 2 through the adhesive member 4. Since the adhesive member 4 having a refractive index substantially equal to the refractive index of the windshield 2 is selected, the light emitted from the light emitting means 5 travels straight without being refracted at the interface between the adhesive member 4 and the windshield 2.
[0031]
Then, as shown in FIG. 2, light that enters the inside of the windshield 2 at an incident angle less than the critical angle passes through the windshield 2 and escapes to the outside.
On the other hand, light that enters the inside of the windshield 2 at an incident angle greater than the critical angle is totally totally reflected on the interface between the outer surface of the windshield 2 and air and the interface between the indoor side surface of the windshield 2 and air. Propagates inside the windshield 2.
The light totally reflected inside the windshield 2 enters the light receiving means 6.
[0032]
Here, in order to obtain the incident angle when the total reflection starts at the interface between air and glass, that is, the critical angle, the following calculation is performed using Snell's law.
The general formula of Snell's law is as shown in the following formula (1). Here, α and α ₀ are angles with respect to the normal line of the interface between the material having the refractive index n and the material having the refractive index n ₀ (α: incidence angle, α ₀ : refraction angle).
[0033]
n ₀ · sin α ₀ = n · sin α (1)
[0034]
When the refractive index n of the glass is n = 1.48 and the refractive index n _{0 of the} air is n ₀ = 1, the condition of the incident angle α for the total reflection inside the glass at the interface between the air and the glass Since the refraction angle α ₀ only needs to satisfy α ₀ ≧ 90 °, the incident angle α at that time is α ≧ 42.5 ° according to Equation (1).
Therefore, if the incident angle α is not less than the critical angle (42.5 °), total reflection in the glass medium occurs.
[0035]
On the other hand, even when water adheres to the glass surface, the condition of the incident angle α for total reflection inside the glass at the interface between water and glass is the same, assuming that the refractive index of water is n ₀ = 1.33. When α is calculated, α ≧ 64.0 °.
Therefore, if the incident angle α is greater than or equal to the critical angle (64.0 °), total reflection occurs in the glass medium.
[0036]
Therefore, if the incident angle α is in the range of 42.5 ° to 64.0 ° (42.5 ° ≦ α ≦ 64.0 °), total reflection is performed inside the glass when water is not attached to the glass. However, when water adheres, it is not totally reflected, and light leaks from the inside of the glass to the outside through the water.
[0037]
In order to cause such reflection, the position where the light emitting means 5 is fixed is adjusted to emit from the light emitting means 5 so as to satisfy the condition of the incident angle α (42.5 ° ≦ α ≦ 64.0 °). The incident angle of light was set. Further, since the incident angle at which the reflected light enters the light receiving means 6 is also symmetrical with the light emitting means 5, the position where the light receiving means 6 is fixed is adjusted so that the reflected light is received without omission.
[0038]
Therefore, when water droplets W are attached to either or both of the outer surface and the indoor side surface of the windshield 2, the light that is being propagated passes through the water droplets W to the outside of the windshield 2, and enters the light receiving means 6. The amount of light that reaches it decreases.
Therefore, when the amount of decrease in the amount of light is detected by the detection circuit 15 and arithmetic processing is performed by the amplification circuit 16, the degree of adhesion of the water droplets W can be known.
[0039]
In the present invention, since all the incident light is used in a range satisfying the condition of the incident angle α (42.5 ° ≦ α ≦ 64.0 °), the water droplets W adhering to the surface of the windshield 2 are separated into discrete light. Since the water droplets W adhering to the surface which is a set of a large number of reflection points are detected instead of the reflection points, the water droplets W adhering to the surface of the windshield 2 are detected as compared with the case of detecting the water droplets W adhering to the discrete reflection points. The detection accuracy of the water droplet W is improved.
[0040]
As shown in FIG. 3, the light receiving means 6 inputs an output signal corresponding to the amount of water droplets W to the wiper driving unit 19.
Then, in the wiper drive unit 19, when the detected amount of water droplets W is greater than or equal to the set value, the wiper 3 is activated at intervals corresponding to the amount of water droplets W attached, while the detected water droplets W are attached. When the amount becomes less than the set value, the wiper 3 is stopped.
[0041]
When the car uses a toll road, the optical transmission / reception means 9 performs optical communication with an optical beacon (entrance beacon, notice beacon, toll gate beacon, etc.) installed on the highway side, and entrance and exit fees Toll collection processing is performed together with the in-vehicle device 20 through information exchange such as location information and vehicle type information.
[0042]
As shown in FIG. 4, the water drop detection sensor 21 with a transmission / reception function according to the second embodiment of the present invention fixes the light emitting means 5, the light receiving means 6, and the optical transmission / reception means 9 to the windshield 2 having the intermediate film 22. The portions of the intermediate film 22 that face the light emitting surface 5 a of the light emitting means 5 and the light receiving surface 6 a of the light receiving means 6 are the reflective films 23 and 24.
In addition, although it was set as the optical transmission / reception means 9 which transmits / receives with light as a transmission / reception means, it can also be set as the sound wave transmission / reception means which transmits / receives with a sound wave. About another structure, it is the same as that of the water drop detection sensor 1 with a transmission / reception function shown in FIG.
[0043]
One reflection film 23 is provided in order to prevent light emitted from the light emitting means 5 that does not totally reflect the inside of the windshield 2 from leaking to the outside.
The other reflection film 24 is provided in order to prevent external light from entering the light receiving means 6 more than necessary as long as it does not block the light totally reflected inside the windshield 2 from entering the light receiving means 6. ing.
[0044]
The operation of the water drop detection sensor 21 with a transmission / reception function configured as described above is the same as that of the water drop and light quantity detection sensor 1 shown in FIG. 2 except that a part of the intermediate film 22 is formed as the reflection films 23 and 24. .
[0045]
As shown in FIG. 5, the water drop detection sensor 31 with a transmission / reception function according to the third embodiment of the present invention is coated with a black ceramic 32 in the form of a band on the periphery of the indoor side surface of the windshield 2. Uncoated portions 32 a of black ceramics 32 are formed, and the light emitting means 5 and the light receiving means 6 are fixed to the uncoated portions 32 a by the adhesive member 4.
[0046]
In addition, each part of the indoor side surface of the windshield 2 where the detection light emitted from the light emitting means 5 is totally reflected forms an interface with air in the same manner as the outer surface of the windshield 2 so as to be totally reflected under the same conditions. Therefore, a non-coated portion 32a of the black ceramic 32 is formed.
[0047]
Then, the optical transmission / reception means 9 is fixed to the uncoated portion 32a by an adhesive member 4 with the transmission / reception surface 9a facing the indoor side surface of the windshield 2 through the air layer 33. The air layer 33 is provided so as to satisfy the same total reflection condition as that of the outer surface of the windshield 2.
In addition, although it was set as the optical transmission / reception means 9 which transmits / receives with light as a transmission / reception means, it can also be set as the sound wave transmission / reception means which transmits / receives with a sound wave.
[0048]
Further, the light emitting means 5, the light receiving means 6, and the optical transmitting / receiving means 9 are covered with a case 34 made of glass, resin, ceramics or metal. The case 34 is fixed to the black ceramic 32 by an adhesive member 35 that also functions as a seal member, and the case 34 and the windshield 2 form a sealed space.
[0049]
In addition, in the air layer 33 formed between the indoor side surface of the windshield 2 and the optical transmission / reception means 9, a molecular sieve or the like is used to prevent dew condensation in the non-coated portion 32a of the black ceramic 32 that is a reflection point. Of dehydrating agent or dry air. Further, the sealed space formed by the case 34 and the windshield 2 is filled with a dehydrating agent 36 such as a molecular sieve or dry air.
In addition, about another structure, it is the same as that of the water drop detection sensor 21 with a transmission / reception function shown in FIG.
[0050]
The place where the black ceramics 32 to which the case 34 is fixed is applied is also a place where the indoor mirror is attached. By sharing the case 34 with the attachment base of the indoor mirror, it is possible to reduce the installation space.
The case 34 is fixed to the black ceramic 32 by the flange member formed in the case 34 after the stopper is fixed to the black ceramic 32 with an adhesive, in addition to the fixing by the sealing member 35 having the above-described adhesive function. Can be fixed to the stopper with a screw.
[0051]
Regarding the operation of the water drop detection sensor 31 with the transmission / reception function configured as described above, the light emitting means 5 and the light receiving means 6 are provided on the periphery of the indoor side surface of the windshield 2 where the black ceramic 32 is applied in a band shape. Except for the action by fixing the optical transmission / reception means 9, it is the same as the water drop detection sensor 21 with a transmission / reception function shown in FIG.
[0052]
As shown in FIG. 6, the water drop detection sensor 41 with a transmission / reception function according to the fourth embodiment of the present invention avoids each part of the indoor side surface of the windshield 2 where the detection light is totally reflected by the light transmission / reception means 9. The structure is the same as that of the water drop detection sensor 31 with a transmission / reception function shown in FIG. 5 except that the adhesive member 4 is fixed to the non-coated portion 32a of the black ceramic 32.
In addition, although it was set as the optical transmission / reception means 9 which transmits / receives with light as a transmission / reception means, it can also be set as the sound wave transmission / reception means which transmits / receives with a sound wave.
[0053]
By providing the light transmitting / receiving means 9 while avoiding each part of the indoor side surface of the windshield 2 where the detection light is totally reflected, it is not necessary to form the air layer 33 for making the same total reflection conditions as the outer surface. Similar to the light emitting means 5 and the light receiving means 6, the light transmitting / receiving means 9 can be directly fixed to the indoor side surface of the windshield 2.
[0054]
The operation of the water drop detection sensor 41 with the transmission / reception function configured as described above is shown in FIG. 5 except for the operation by avoiding each part of the indoor side surface of the windshield 2 where the detection light is totally reflected by the optical transmission / reception means 9. It is the same as the water drop detection sensor 31 with a transmission / reception function shown.
[0055]
【The invention's effect】
As described above, according to the first aspect of the present invention, no prism is required and the structure is simplified. In addition, the detection accuracy is improved compared to the case where only water droplets adhering to the discrete reflection points are detected because the water droplets adhering to the surface that is a set of many reflection points are detected instead of discrete light reflection points. To do.
Furthermore, since the transmission / reception means capable of transmitting / receiving to / from the outside of the vehicle is provided, the application range as a sensor is expanded.
[0056]
According to the second aspect of the present invention, the portion of the intermediate film that faces the light emitting surface of the light emitting means and the light receiving surface of the light receiving means is used as the reflective film. It is possible to prevent non-reflected light from leaking to the outside and prevent external light from entering the light receiving means.
Moreover, the application range as a sensor expands by providing the transmission / reception means which can transmit / receive with the exterior of a vehicle.
[0057]
According to the invention of claim 3, since the light emitting means, the light receiving means, and the optical beacon transmitting / receiving means are fixed to the peripheral portion of the indoor side surface of the window glass where the black ceramic is applied in a band shape, Mounting space can be shared with the mounting base, etc., contributing to space saving.
Moreover, the application range as a sensor expands by providing the transmission / reception means which can transmit / receive with the exterior of a vehicle.
[0058]
According to the invention of claim 4, since the transmitting / receiving means is fixed to avoid the portions on the indoor side surface of the wind glass where the detection light is totally reflected, it is directly fixed to the indoor side surface of the wind glass without an air layer. Can be installed easily.
Moreover, the application range as a sensor expands by providing the transmission / reception means which can transmit / receive with the exterior of a vehicle.
[0059]
According to the invention which concerns on Claim 5, the application range as a sensor spreads by having set the transmission / reception means as the optical transmission / reception means which transmits / receives by light.
[0060]
According to the invention which concerns on Claim 6, the application range as a sensor spreads by having set the transmission / reception means as the sound wave transmission / reception means which transmits / receives by a sound wave.
[Brief description of the drawings]
FIG. 1 is a perspective view of a front part of a vehicle equipped with a water drop detection sensor with a transmission / reception function according to the present invention. FIG. 2 is a diagram illustrating the configuration of a water drop detection sensor with a transmission / reception function according to a first embodiment of the invention. 3 is a configuration diagram in which a water droplet detection sensor with a transmission / reception function according to the present invention is applied to a wiper control and an automatic toll collection system. FIG. 4 is an explanatory diagram of a configuration of a water droplet detection sensor with a transmission / reception function according to a second embodiment of the present invention. FIGS. 5A and 5B are configuration explanatory views of a water drop detection sensor with a transmission / reception function according to a third embodiment of the present invention, wherein FIG. 5A is a cross-sectional view, and FIG. 5B is a rear view; BRIEF DESCRIPTION OF THE DRAWINGS It is structure explanatory drawing of the water drop detection sensor with a transmission / reception function which concerns on embodiment, (a) is sectional drawing, (b) is a rear view. [FIG. 7] The block diagram of the conventional water drop detection sensor
1, 2, 31, 41 ... Water drop detection sensor with transmission / reception function, 2 ... Wind shield (wind glass), 3 ... Wiper, 4 ... Adhesive member, 5 ... Light emitting means, 5a ... Light emitting surface, 6 ... Light receiving means, 6a ... Light-receiving surface, 7, 8 ... Light-shielding member, 9 ... Light transmitting / receiving means, 9a ... Transmitting / receiving surface, 22 ... Intermediate film, 23,24 ... Reflective film, 32 ... Black ceramic, 32a ... Non-coated portion of black ceramic, 33 ... Air Layer, 34 ... Case, W ... Water drop.

Claims

A water drop detection sensor with a transmission / reception function for detecting water droplets attached to the window glass by a change in the amount of reflected light of the detection light and transmitting / receiving to / from the outside, the light emitting means for making the detection light incident on the window glass, and The light receiving means for detecting the light totally reflected in the window glass of the detection light is provided on the indoor side surface of the window glass, and the transmission / reception means for transmitting / receiving to / from the outside avoids the reflection point portion of the detection light. A water droplet detection sensor with a transmission / reception function, which is provided on a side surface of a glass interior.

A water droplet detection sensor with a transmission / reception function for transmitting / receiving to / from the outside while detecting water droplets attached to a window glass having an intermediate film by a change in the amount of reflected light for detection light, and causing the detection light to be incident on the window glass A light receiving means for detecting light totally reflected in the window glass among the light emitting means and the detection light is provided on the indoor side surface of the window glass, and a transmission / reception means for transmitting / receiving to / from the outside is provided with a reflection spot portion of the detection light. A water droplet detection sensor with a transmission / reception function, which is provided on an indoor side surface of the window glass that is avoided, and a portion of the intermediate film facing the light receiving means is a reflection film.

A water droplet detection sensor with a transmission / reception function for transmitting / receiving to / from the outside while detecting water droplets attached to a window glass having an intermediate film by a change in reflected light amount of detection light, and causing the detection light to be incident on the window glass A light receiving means for detecting light totally reflected in the window glass among the light emitting means and the detection light is provided on a non-coated portion of the black ceramic on the indoor side surface of the window glass, and the reflection point of the detection light A water droplet detection sensor with a transmission / reception function, wherein the non-application portion of the black ceramic is provided with a transmission / reception means for transmitting / receiving to / from the outside via an air layer.

A water droplet detection sensor with a transmission / reception function for transmitting / receiving to / from the outside while detecting water droplets attached to a window glass having an intermediate film by a change in reflected light amount of detection light, and causing the detection light to be incident on the window glass A light receiving means for detecting light totally reflected in the window glass out of the light emitting means and the detection light is provided on a non-coated portion of the black ceramic on the indoor side surface of the window glass, and the reflection spot portion of the detection light A water droplet detection sensor with a transmission / reception function, wherein a non-coating portion of black ceramics is provided in a non-coating portion of the black ceramics avoiding the reflection point portion, and transmitting / receiving means for transmitting / receiving to / from the outside.

5. The water drop detection sensor with a transmission / reception function according to claim 1, wherein the transmission / reception means is an optical transmission / reception means for performing transmission / reception with light.

5. The water drop detection sensor with a transmission / reception function according to claim 1, wherein the transmission / reception means is a sound wave transmission / reception means for transmitting / receiving sound waves.