JPS647314Y2 - - Google Patents
Info
- Publication number
- JPS647314Y2 JPS647314Y2 JP1981065605U JP6560581U JPS647314Y2 JP S647314 Y2 JPS647314 Y2 JP S647314Y2 JP 1981065605 U JP1981065605 U JP 1981065605U JP 6560581 U JP6560581 U JP 6560581U JP S647314 Y2 JPS647314 Y2 JP S647314Y2
- Authority
- JP
- Japan
- Prior art keywords
- light
- light guide
- totally reflected
- transparent
- transparent light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000001514 detection method Methods 0.000 claims description 37
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 27
- 239000013307 optical fiber Substances 0.000 claims description 24
- 239000005357 flat glass Substances 0.000 description 17
- 238000010586 diagram Methods 0.000 description 4
- NCGICGYLBXGBGN-UHFFFAOYSA-N 3-morpholin-4-yl-1-oxa-3-azonia-2-azanidacyclopent-3-en-5-imine;hydrochloride Chemical compound Cl.[N-]1OC(=N)C=[N+]1N1CCOCC1 NCGICGYLBXGBGN-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Landscapes
- Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Description
【考案の詳細な説明】
本考案は水滴付着検知装置に関し、特に自動車
のヘツドランプ、ウインドガラス等に水滴が付着
したことを検知する水滴付着検知装置に関するも
のである。[Detailed Description of the Invention] The present invention relates to a water droplet adhesion detection device, and more particularly to a water droplet adhesion detection device for detecting water droplets adhering to an automobile headlamp, window glass, etc.
自動車などにおいては、ヘツドランプ、ウイン
ドガラス等に付着する雨滴、結露、結氷、雪、泥
水などをも含む水滴によつて視界が制限され、運
転に支障をきたすことがある。 In automobiles, visibility may be restricted by water droplets, including raindrops, dew condensation, ice, snow, and muddy water, adhering to headlights, windshields, etc., and this may impede driving.
このため、第１図に示す如く、被検知物たるウ
インドガラスａに光線が入射した場合、入射角が
臨界角より大きいとウインドガラスａと空気との
境界面において全反射が生じ、ウインドガラスａ
より屈折率の小さい水滴がウインドガラスａの表
面に付着すると全反射する光線が変化する原理を
利用した水滴付着検知装置が提案されている。よ
り詳しく従来の装置について述べると、ウインド
ガラスａの表面を検知表面a1とし、ウインドガラ
スａの裏面に一端を傾斜面としたプリズムｂ，ｅ
を一定角度で略八字状に設け、一方のプリズムｂ
の他端がわにレンズｃを介して発光素子ｄを配設
すると共に、他方のプリズムｅの他端がわにレン
ズｆを介して受光素子ｇを配設し、発光素子ｄか
ら投光される光をレンズｃで集束し、集束した光
をウインドガラスａ中へプリズムｂで一定角度で
入射させた被検知表面a1で全反射させ、数回全反
射した光をプリズムｅで外部に取り出しレンズｆ
で集束して受光素子ｇで受光するように構成され
ている。なお、前記一定角度とは、ウインドガラ
スａと空気との境界面の臨界角より大きく、かつ
ウインドガラスａと水滴との境界面の臨界角より
も小さな角度としてある。このことにより検知表
面a1に水滴が付着した場合、全反射する光が変化
し、受光素子ｇの受光量が変化するので水滴の付
着が検知できるものである。 Therefore, as shown in Fig. 1, when a light beam is incident on the window glass a, which is the object to be detected, if the angle of incidence is larger than the critical angle, total reflection will occur at the interface between the window glass a and the air, and the window glass a
A water droplet adhesion detection device has been proposed that utilizes the principle that when water droplets with a smaller refractive index adhere to the surface of the window glass a, the total reflected light changes. To describe the conventional device in more detail, the front surface of the window glass a is used as the detection surface a1 , and the back surface of the window glass a is equipped with prisms b and e whose one end is an inclined surface.
are arranged at a constant angle in a substantially eight-shape shape, and one prism b
A light emitting element d is disposed on the other end of the prism e through a lens c, and a light receiving element g is disposed on the other end of the prism e through a lens f, so that light is emitted from the light emitting element d. The focused light is incident on the window glass a at a fixed angle with a prism b, and is totally reflected on the detection surface a1.The light that has been totally reflected several times is taken out to the outside by a prism e. lens f
It is configured so that the light is focused by the light receiving element g and received by the light receiving element g. Note that the above-mentioned constant angle is an angle that is larger than the critical angle of the interface between the window glass a and the air and smaller than the critical angle of the interface between the window glass a and the water droplet. As a result, when a water droplet adheres to the detection surface a1 , the total reflected light changes, and the amount of light received by the light receiving element g changes, so that the adhesion of the water droplet can be detected.
しかし乍ら、このような従来の水滴付着検知装
置は、発光がわと受光がわが別々に構成されてい
るので、ウインドガラスａに取付けるのに多くの
手間を必要とし、また、取付けに際し、発光側と
受光側のプリズムの角度及び位置の調整が非常に
難しいという問題がある。これらの問題を改善す
るため、発光側のプリズムと受光側のプリズムと
を一体にすることが考えられるが、たゞ単に発光
側のプリズムと受光側のプリズムとを一体にした
だけでは、プリズム全体の幅が大きくなつて検出
装置全体が大型化し、例えばヘツドランプ用とし
た場合見苦しくなるという問題がある。 However, such conventional water droplet adhesion detection devices have separate light-emitting and light-receiving parts, so it requires a lot of effort to install them on the window glass a. There is a problem in that it is very difficult to adjust the angle and position of the prisms on the side and light receiving side. In order to improve these problems, it is possible to integrate the light emitting side prism and the light receiving side prism, but simply integrating the light emitting side prism and the light receiving side prism will result in the entire prism As the width of the detection device increases, the overall size of the detection device increases, and there is a problem that it becomes unsightly when used for a headlamp, for example.
本考案は、前記の如き従来技術の問題点を改善
し、取付けが容易で、取付個所での受光器等の位
置調整を不要とし、しかも、装置全体を小型化す
ることができる水滴付着検知装置を提供すること
を目的とする。本考案は、前記の如き目的を達成
するため、透明導光体と、２本の光フアイバー
と、発光素子と受光素子とよりなり、前記透明導
光体は、前面あるいは該前面が取付く被検知物の
表面を検知表面とすると共に、両側面を後方が広
がるように傾斜させた断面略台形に形成し、前記
透明導光体の底部に前記各光フアイバーの一端を
互に平行に埋設してその先端を前記透明導光体の
傾斜側面と対向せしめ、かつ該各光フアイバーの
他端に前記発光素子と前記受光素子とを配設し、
前記一方の光フアイバーの一端より投光される光
を前記透明導光体の一方の傾斜側面で全反射せし
めて前記検知表面に入射させ、該検知表面で全反
射した光を透明導光体の他方の側面で全反射させ
て前記他方の光フアイバーの一端に投光すべくな
したことを特徴とする。 The present invention is a water droplet adhesion detection device that improves the problems of the prior art as described above, is easy to install, does not require position adjustment of the light receiver, etc. at the installation location, and can be miniaturized as a whole. The purpose is to provide In order to achieve the above object, the present invention consists of a transparent light guide, two optical fibers, a light emitting element and a light receiving element, and the transparent light guide has a front surface or a cover to which the front surface is attached. The surface of the object to be detected is used as a detection surface, and the cross section is formed into a substantially trapezoidal shape with both sides inclined so that the rear side widens, and one end of each of the optical fibers is buried in the bottom of the transparent light guide in parallel with each other. the tip of the optical fiber is opposed to the inclined side surface of the transparent light guide, and the light emitting element and the light receiving element are disposed at the other end of each optical fiber,
The light projected from one end of the one optical fiber is totally reflected on one inclined side surface of the transparent light guide and incident on the detection surface, and the light totally reflected on the detection surface is reflected on the transparent light guide. It is characterized in that the light is totally reflected on the other side surface and projected onto one end of the other optical fiber.
以下、図面を参照して本考案にかかる水滴付着
検知装置の一実施例を説明する。 Hereinafter, one embodiment of the water droplet adhesion detection device according to the present invention will be described with reference to the drawings.
第２図は本考案の一実施例を示す概略構成図で
あつて、図中１は透明導光体、２及び３はそれぞ
れ光フアイバーを示し、４は発光素子、５は受光
素子を示す。 FIG. 2 is a schematic configuration diagram showing an embodiment of the present invention, in which 1 is a transparent light guide, 2 and 3 are optical fibers, 4 is a light emitting element, and 5 is a light receiving element.
透明導光体１はガラスあるいはアクリル等の透
明合成樹脂からなるもので、前面１１と後面１４
とが平行で、左右の側面１２，１３が後方に拡が
るように傾斜した断面略台形に形成し、その前面
１１および両傾斜側面１２，１３は平滑面に形成
され、前面１１を検知表面Ａとしてある。そし
て、底部には２本の光フアイバー２，３の一端が
互に平行に埋設されてその先端を前記傾斜側面１
２，１３と対向させており、また各光フアイバー
２，３の他端には各々発光素子４と受光素子５と
が配設してある。 The transparent light guide 1 is made of glass or transparent synthetic resin such as acrylic, and has a front surface 11 and a rear surface 14.
are parallel to each other, and the left and right side surfaces 12 and 13 are formed into a substantially trapezoidal cross section that is inclined so as to spread backward, and the front surface 11 and both inclined side surfaces 12 and 13 are formed as smooth surfaces, and the front surface 11 is used as the detection surface A. be. One ends of two optical fibers 2 and 3 are buried parallel to each other in the bottom, and their tips are connected to the inclined side surface 1.
2 and 13, and a light emitting element 4 and a light receiving element 5 are disposed at the other end of each optical fiber 2 and 3, respectively.
発光素子４は発光ダイオード、白熱バルブ等か
らなり、この例での発光素子４は一方の光フアイ
バー２の他端に発光素子４から放射状に発光した
光を指向せしめる指向レンズ４１を具備してお
り、受光素子５はフオトトランジスター、フオト
ダイオード、cds等からなり、その受光素子５を
受光した光量の変化を読取る検知回路に接続して
ある。 The light emitting element 4 is composed of a light emitting diode, an incandescent bulb, etc., and the light emitting element 4 in this example is equipped with a directional lens 41 at the other end of one optical fiber 2 to direct the light emitted radially from the light emitting element 4. The light receiving element 5 is composed of a phototransistor, a photodiode, a CDS, etc., and is connected to a detection circuit that reads changes in the amount of light received.
そして、前記透明導光体は、一方の光フアイバ
ー２の一端より投光された光を一方の傾斜側面１
２で全反射させて検知表面Ａに入射させ、該検知
表面Ａで全反射した光を他方の傾斜側面１３で全
反射させて他方の光フアイバー３の一端に投光す
べく構成されている。 The transparent light guide transmits light projected from one end of one optical fiber 2 to one inclined side surface 1.
2, the light is totally reflected by the detection surface A, and the light totally reflected by the detection surface A is totally reflected by the other inclined side surface 13 and projected onto one end of the other optical fiber 3.
更に詳しく述べると、一方の側面１２で全反射
した光が検知表面Ａに入射する角度θは、検知表
面Ａで全反射を起し、この検知表面Ａに透明導光
体１よりも屈折率の低い水滴が付着したときは検
知表面Ａで全反射を起さずに光が水滴内へ透過し
て変化してしまう角度としてある。即ち、具体的
に述べると、入射する角度θは、透明導光体がア
クリル樹脂の場合屈折率n1＝1.5、空気の屈折率
n0＝1.0であるから、全反射が始まる角度θc1（臨界
角）は、
θc1＝sin-1（n0／n1）＝41.8゜ …(1)
次に検知表面Ａに水滴が付着したときに上記の
入射する光が水滴内へ侵入しない角度、即ち、水
滴が付着していても検知表面Ａで全反射してしま
う角度θc2は、水滴の屈折率n2＝1.33とすると
θc2＝sin-1（n2／n1）＝62.45゜ …(2)
従つて、上記入射する角θは、上記(1)，(2)式を
満足する条件下の41.8゜＜θ＜62.25゜の範囲とし、
この入射する角度θを満足すべく一方の傾斜側面
１２は、一方の光フアイバー２の一端より投光さ
れる光を全反射（臨界角＝41.8゜以上）させる角
度で傾斜させている。また、他方の傾斜側面１３
は、検知表面Ａで全反射した光がこの他方の側面
１３で全反射する角度に傾斜しており、他方の光
フアイバー３の一端は他方の傾斜側面１３で全反
射した光を最大に受光し得る位置に埋設してあ
る。 More specifically, the angle θ at which the light totally reflected on one side surface 12 is incident on the detection surface A is such that total reflection occurs on the detection surface A, and this detection surface A has a refractive index higher than that of the transparent light guide 1. When a small water droplet is attached, the angle is such that the light is transmitted into the water droplet and changes without causing total reflection on the detection surface A. Specifically, the incident angle θ is the refractive index n 1 = 1.5 when the transparent light guide is made of acrylic resin, and the refractive index of air.
Since n 0 = 1.0, the angle θ c1 (critical angle) at which total reflection begins is θ c1 = sin -1 (n 0 /n 1 ) = 41.8°...(1) Next, a water droplet adheres to the sensing surface A. The angle at which the incident light does not enter the water droplet, that is, the angle at which it is totally reflected by the detection surface A even if there is a water droplet, is θ c2 , assuming that the refractive index of the water droplet is n 2 = 1.33. c2 = sin -1 (n 2 / n 1 ) = 62.45° ...(2) Therefore, the above incident angle θ is 41.8° < θ < 62.25 under the condition that satisfies equations (1) and (2) above. Within the range of ゜,
In order to satisfy this incident angle θ, one inclined side surface 12 is inclined at an angle that causes total reflection (critical angle=41.8° or more) of the light projected from one end of one optical fiber 2. In addition, the other inclined side surface 13
is inclined at such an angle that the light totally reflected on the detection surface A is totally reflected on the other side surface 13, and one end of the other optical fiber 3 receives the maximum amount of light totally reflected on the other inclined side surface 13. It is buried in a location where it can be obtained.
このように構成した本考案の水滴付着検知装置
は、例えば被検知物６がヘツドランプである場合
には、第３図に示す如く、ヘツドランプ６に装着
したワイパー６１が払拭する範囲内に検知表面Ａ
が前面レンズ６２と平行面内に位置するようにヘ
ツドランプ６に並設する。従つて、飛来する水滴
が前面レンズ６２に付着すると検知表面Ａにも付
着することになるので、並設した透明導光体１の
検知表面Ａで前面レンズ６２に付着する水滴の有
無を検知することができる。なお、この場合、透
明導光体１の両側面１２，１３には水滴付着防止
用のカバーを取付けておくことが好ましい。 The water droplet adhesion detection device of the present invention configured in this manner, for example, when the object to be detected 6 is a headlamp, as shown in FIG.
are arranged in parallel with the headlamp 6 so that they are located in a plane parallel to the front lens 62. Therefore, when flying water droplets adhere to the front lens 62, they also adhere to the detection surface A, so the presence or absence of water droplets adhering to the front lens 62 is detected by the detection surface A of the transparent light guide 1 arranged in parallel. be able to. In this case, it is preferable to attach a cover to both side surfaces 12 and 13 of the transparent light guide 1 to prevent the adhesion of water droplets.
また、被検知物６がウインドガラスである場合
には、第４図に示す如く、透明導光体１の前面１
１を予めウインドガラス６の肉厚分だけ切削し、
ウインドガラス６の内面に透明導光体１の前面１
１を透明接着剤で接着固定する。この場合、透明
導光体１はウインドガラス６と同一屈折率の材料
を使用し、また接着剤も同一屈折率のものを使用
する。そして、ウインドガラス６の表面を検知表
面Ａとする。 Further, when the detected object 6 is a window glass, as shown in FIG. 4, the front surface 1 of the transparent light guide 1
1 is cut in advance by the thickness of the window glass 6,
The front surface 1 of the transparent light guide 1 is placed on the inner surface of the window glass 6.
1 with transparent adhesive. In this case, the transparent light guide 1 is made of a material having the same refractive index as the window glass 6, and the adhesive has the same refractive index. The surface of the window glass 6 is defined as a detection surface A.
このように、本考案の水滴付着検知装置は、発
光がわと受光がわを透明導光体１によつて一体と
なつているので取付けが簡単となり、また、透明
導光体１内で発光素子４の光が数回全反射して受
光器５に再帰するように予め位置調整されている
ので、取付けに際しての煩雑化は全くない。しか
も、透明導光体１の底部に２本の光フアイバー
２，３の各一端を互に平行に埋設し、その一方の
光フアイバー２から投光される光を一方の傾斜側
面１２で全反射させて検知表面に入射させ、該検
知表面で全反射した光を他方の傾斜側面で全反射
させて他方の光フアイバー３の一端に投光するよ
うにしているので、透明導光体１の横方向の寸法
がコンパクトになり、かつ、各光フアイバー２，
３が平行であるので、無理なく束ねて検出装置全
体の小型化をはかることができる。 In this way, the water droplet adhesion detection device of the present invention is easy to install because the light emitting side and the light receiving side are integrated through the transparent light guide 1. Since the position is adjusted in advance so that the light from the element 4 is totally reflected several times and returns to the light receiver 5, there is no need for any complication during installation. Moreover, one end of each of the two optical fibers 2 and 3 is buried in the bottom of the transparent light guide 1 in parallel with each other, and the light emitted from one of the optical fibers 2 is totally reflected by one of the inclined side surfaces 12. The light that is totally reflected on the detection surface is totally reflected on the other inclined side surface and projected onto one end of the other optical fiber 3, so that the The dimension in the direction is compact, and each optical fiber 2,
3 are parallel, it is possible to easily bundle them together and downsize the entire detection device.
以上述べたように、本考案の水滴付着検知装置
は、取付けが容易で位置調整を必要としないばか
りでなく、特に装置全体の小型化をはかることが
できる効果がある。 As described above, the water droplet adhesion detection device of the present invention is not only easy to install and does not require position adjustment, but also particularly effective in reducing the size of the entire device.
第１図は従来例を示す構成図、第２図は本考案
にかかる水滴付着検知装置の一実施例を示す構成
図、第３図及び第４図はそれぞれ本考案の使用例
を示す説明図である。
１……透明導光体、１１……前面、１２，１３
……傾斜側面、１４……底面、２，３……光フア
イバー、４……発光素子、５……受光素子、６…
…被検知物（ヘツドランプ、ウインドガラス）、
Ａ……検知表面。
Fig. 1 is a block diagram showing a conventional example, Fig. 2 is a block diagram showing an embodiment of a water droplet adhesion detection device according to the present invention, and Figs. 3 and 4 are explanatory diagrams showing usage examples of the present invention, respectively. It is. 1... Transparent light guide, 11... Front, 12, 13
... Slanted side surface, 14 ... Bottom surface, 2, 3 ... Optical fiber, 4 ... Light emitting element, 5 ... Light receiving element, 6 ...
...Detected object (head lamp, window glass),
A...Detection surface.
Claims (1)
子と受光素子とよりなり、その透明導光体は、前
面あるいは該前面が取付く被検知物の表面を検知
表面とすると共に、両側面を後方が広がるように
傾斜させた断面略台形に形成し、前記透明導光体
の底部に前記各光フアイバーの一端を互に平行に
埋設してその先端を前記透明導光体の傾斜側面と
対向せしめ、かつ該各光フアイバーの他端に前記
発光素子と前記受光素子とを配設し、前記一方の
光フアイバーの一端より投光される光を前記透明
導光体の一方の傾斜側面で全反射せしめて前記検
知表面に入射させ、該検知表面で全反射した光を
透明導光体の他方の側面で全反射させて前記他方
の光フアイバーの一端に投光すべく構成したこと
を特徴とする水滴付着検知装置。 The transparent light guide is composed of a transparent light guide, two optical fibers, a light emitting element and a light receiving element. is formed into a substantially trapezoidal cross-section with a slope that widens at the rear, and one end of each of the optical fibers is embedded in the bottom of the transparent light guide in parallel with each other, and the tip thereof is connected to the inclined side surface of the transparent light guide. The light emitting element and the light receiving element are arranged to face each other and at the other end of each of the optical fibers, and the light emitted from one end of the one optical fiber is transmitted to one inclined side surface of the transparent light guide. The light is totally reflected and incident on the detection surface, and the light totally reflected on the detection surface is totally reflected on the other side of the transparent light guide and projected onto one end of the other optical fiber. Water droplet adhesion detection device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1981065605U JPS647314Y2 (en) | 1981-05-08 | 1981-05-08 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1981065605U JPS647314Y2 (en) | 1981-05-08 | 1981-05-08 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57179150U JPS57179150U (en) | 1982-11-13 |
| JPS647314Y2 true JPS647314Y2 (en) | 1989-02-27 |
Family
ID=29861642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1981065605U Expired JPS647314Y2 (en) | 1981-05-08 | 1981-05-08 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS647314Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11509932A (en) * | 1996-05-24 | 1999-08-31 | リビー−オーウェンズ−フォード・カンパニー | Compact water drop sensor with collimator lens and prism coupler |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4044163B2 (en) * | 1995-11-15 | 2008-02-06 | アークレイ株式会社 | Liquid detection method and apparatus |
| DE102018206548A1 (en) * | 2018-04-27 | 2019-10-31 | Robert Bosch Gmbh | Method for detecting damage and / or contamination on a transparent covering material of an optoelectronic sensor, system, optoelectronic sensor and means of locomotion |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5722945A (en) * | 1980-07-14 | 1982-02-06 | Yoshiji Shishido | Automatic windshield wiper with rainfall sensor |
-
1981
- 1981-05-08 JP JP1981065605U patent/JPS647314Y2/ja not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5722945A (en) * | 1980-07-14 | 1982-02-06 | Yoshiji Shishido | Automatic windshield wiper with rainfall sensor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11509932A (en) * | 1996-05-24 | 1999-08-31 | リビー−オーウェンズ−フォード・カンパニー | Compact water drop sensor with collimator lens and prism coupler |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57179150U (en) | 1982-11-13 |
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