JP2995828B2 - Reflective optical device for vehicles - Google Patents
Reflective optical device for vehiclesInfo
- Publication number
- JP2995828B2 JP2995828B2 JP24156990A JP24156990A JP2995828B2 JP 2995828 B2 JP2995828 B2 JP 2995828B2 JP 24156990 A JP24156990 A JP 24156990A JP 24156990 A JP24156990 A JP 24156990A JP 2995828 B2 JP2995828 B2 JP 2995828B2
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- JP
- Japan
- Prior art keywords
- light
- opening
- receiving
- emitting
- case
- Prior art date
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- Photo Coupler, Interrupter, Optical-To-Optical Conversion Devices (AREA)
- Optical Radar Systems And Details Thereof (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、反射型光学装置に係り、詳しくは、発光
素子の光を被対象物に照射しその反射光を受光素子にて
受光して被対象物の存在の有無や被対象物までの距離測
定等を行う車両用反射型光学装置に関するものである。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection type optical device, and more specifically, irradiates an object with light from a light emitting element and receives the reflected light with a light receiving element. The present invention relates to a reflective optical device for a vehicle for measuring the presence or absence of an object, measuring the distance to the object, and the like.
従来、反射型光学装置の一例としての自動車用障害物
検知装置が、例えば特開昭59−92372号公報に示されて
いる。この装置は、ケース内の発光素子からレーザ光を
ケースの発光用開口部を通して被対象物に向けて照射す
るとともに、被対象物にて反射したレーザ光をケースの
受光開口部を通してケース内に導入して受光素子にて受
光し、この発光から受光までの時間にて距離測定を行う
ものである。そして、この装置を車に搭載する時には外
部雰囲気からの保護及び美観保持のために、発光用開口
部と受光用開口部とが光透過板（カバー）にて覆われ
る。2. Description of the Related Art Conventionally, an obstacle detecting device for a vehicle as an example of a reflection type optical device is disclosed in, for example, JP-A-59-92372. This device irradiates laser light from the light emitting element in the case to the object through the light emitting opening of the case, and introduces the laser light reflected by the object into the case through the light receiving opening of the case. Then, the light is received by the light receiving element, and the distance is measured by the time from the emission to the light reception. When this device is mounted on a vehicle, the light-emitting opening and the light-receiving opening are covered with a light-transmitting plate (cover) for protection from an external atmosphere and maintaining aesthetic appearance.
しかしながら、１枚の板材よりなる光透過板（カバ
ー）を装着すると、発光素子からのレーザ光が光透過板
内を全反射しながら伝搬して受光用開口部に入り測定で
きなくなってしまう。そのため、例えば、STC（Sensiti
vity Time Control）回路が用いられているが、処理回
路が複雑であるのでコストアップを招いてしまってい
た。However, when a light transmitting plate (cover) made of one plate material is attached, laser light from the light emitting element propagates while totally reflecting inside the light transmitting plate, and enters the light receiving opening, making it impossible to measure. Therefore, for example, STC (Sensiti
vity Time Control) circuit is used, but the processing circuit is complicated, resulting in an increase in cost.
この発明の目的は、簡単な構成にて、光透過板を介し
ての受光素子への光伝搬に起因する障害を低減できる車
両用反射型光学装置を提供することにある。SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicular reflective optical device that can reduce a trouble caused by light propagation to a light receiving element via a light transmitting plate with a simple configuration.
上記の目的を達成するために、この発明においては、
ケース内に配置された発光素子と、前記ケースに形成さ
れ、前記発光素子からの光を被対象物に向けて照射する
ための発光用開口部と、前記発光用開口部の近傍におい
て前記ケースに形成され、前記被対象物で反射した前記
発光素子による光を導入するための受光用開口部と、前
記ケース内に配置され、前記受光用開口部からの光を受
光する受光素子と、前記発光用開口部と受光用開口部と
を覆い、前記発光素子及び前記受光素子を外部雰囲気か
ら保護する光透過板とを備え、前記光透過板における前
記発光用開口部と受光用開口部を区切る領域で、かつ前
記発光素子及び前記受光素子が配置される側の表面上に
のみ光伝搬阻止領域を設けた車両用反射型光学装置をそ
の要旨とするものである。In order to achieve the above object, in the present invention,
A light-emitting element arranged in a case, a light-emitting opening formed in the case, and for irradiating light from the light-emitting element toward an object; and a light-emitting opening in the case near the light-emitting opening. A light-receiving opening formed to receive light from the light-emitting element reflected by the object; a light-receiving element disposed in the case to receive light from the light-receiving opening; A light-transmitting plate that covers the light-receiving element and the light-receiving element, and that protects the light-emitting element and the light-receiving element from the external atmosphere, and that separates the light-emitting element and the light-receiving element in the light-transmitting element. The gist of the invention is a reflection type optical device for a vehicle, in which a light propagation blocking region is provided only on a surface on a side where the light emitting element and the light receiving element are arranged.
発光素子の光が発光用開口部を通って被対象物に照射
され、被対象物で反射した発光素子による光が受光用開
口部を通り受光素子にて受光される。この際、発光素子
からの光が発光用開口部から受光用開口部側へと光透過
板内を全反射しながら伝搬しようとするが、発光素子及
び前記受光素子が配置される側の表面上にのみ光伝搬阻
止領域を設けているため、同光伝搬阻止領域により阻害
され受光用開口部に到ることが抑制される。Light from the light-emitting element is applied to the object through the light-emitting opening, and light from the light-emitting element reflected by the object passes through the light-receiving opening and is received by the light-receiving element. At this time, light from the light emitting element tends to propagate from the light emitting opening to the light receiving opening side while being totally reflected in the light transmitting plate, but on the surface on the side where the light emitting element and the light receiving element are arranged. Since the light propagation blocking region is provided only in the light transmission blocking region, it is possible to prevent the light propagation blocking region from reaching the light receiving opening.
以下、この発明を、レーザ光を用いた距離測定装置
（レーザレーダ）に具体化した一実施例を図面に基づい
て説明する。Hereinafter, an embodiment in which the present invention is embodied in a distance measuring apparatus (laser radar) using laser light will be described with reference to the drawings.
第２図は距離測定装置の概略構成を示す図、第３図は
第２図のＡ−Ａ断面図であり、この距離測定装置は装置
本体１と演算処理部２と表示器３とからなる。装置本体
１の全体ケース４は左右（第２図上下）に細長い四角箱
状をなし、その前面（第２図右側面）が開口されてい
る。全体ケース４内には、発光用ケース５と受光用ケー
ス６とが左右に隣接した状態で収納されている。両ケー
ス5,6はともに有底円筒状をなし、前面にはそれぞれ開
口部5a,6aが形成されている。FIG. 2 is a diagram showing a schematic configuration of a distance measuring device, and FIG. 3 is a sectional view taken along line AA of FIG. 2. This distance measuring device comprises an apparatus main body 1, an arithmetic processing section 2, and a display 3. . The entire case 4 of the apparatus main body 1 is formed in an elongated rectangular box shape on the left and right (up and down in FIG. 2), and the front surface (right side in FIG. 2) is opened. In the entire case 4, a light emitting case 5 and a light receiving case 6 are housed adjacent to each other on the left and right. Both cases 5, 6 have a bottomed cylindrical shape, and openings 5a, 6a are formed on the front surface, respectively.
発光用ケース５内の奥部には基板７が配置され、基板
７の前面には発光素子としてのレーザダイオード８が前
方へ向けて固定されている。又、基板７の後面には発光
回路を構成する各素子９が配置され、この発光回路はレ
ーザダイオード８を駆動してパルスレーザ光の発光を行
わせる。発光用ケース５の開口部5aには凸レンズ10が配
置され、この凸レンズ10にてレーザダイオード８の発光
するレーザ光が所定の拡散角度に絞られる。A substrate 7 is arranged at the back of the light-emitting case 5, and a laser diode 8 as a light-emitting element is fixed forward on the front surface of the substrate 7. On the rear surface of the substrate 7, elements 9 constituting a light emitting circuit are arranged. The light emitting circuit drives a laser diode 8 to emit a pulsed laser beam. A convex lens 10 is disposed in the opening 5a of the light emitting case 5, and the laser light emitted from the laser diode 8 is narrowed by the convex lens 10 to a predetermined diffusion angle.
又、受光用ケース６内の奥部には基板11が配置され、
基板11の前側には受光素子としてのPINフォトダイオー
ド12が前方へ向けて固定されている。又、基板11の後面
には受光回路を構成する各素子13が配置され、この受光
回路はPINフォトダイオード12の受光信号を増幅する。
受光用ケース６の開口部6aには被対象物からの反射光を
集光するためのフレネルレンズ14が配置されている。In addition, a substrate 11 is disposed at the back in the light receiving case 6,
On the front side of the substrate 11, a PIN photodiode 12 as a light receiving element is fixed forward. In addition, on the rear surface of the substrate 11, each element 13 constituting the light receiving circuit is arranged, and this light receiving circuit amplifies the light receiving signal of the PIN photodiode 12.
In the opening 6a of the light receiving case 6, a Fresnel lens 14 for condensing the reflected light from the object is arranged.
発光用ケース５の前面にはその開口部5aの形状に対応
して円環状に形成されたゴム材15が取り付けられてい
る。第３図に示すように、このゴム材15の幅Ｗは２〜3m
mとなっている。全体ケース４の開口部には、ABS樹脂に
よって四角環状に形成された枠体16が固着されており、
光透過板（アウタカバー）17が枠体16に取り付けられて
いる。この光透過板17は、第４図に示すように、アクリ
ル系樹脂を横長板状に形成したものであり、黒色透明で
ある。尚、黒色透明に限らず、使用している信号の波長
を通過させることができればよく、無色透明でもよい。
そして、この光透過板17によって開口部5a,6aが覆われ
ている。光透過板17の後面においてゴム材15と接する部
分は他の部分よりも粗面に形成されており、この部分が
光伝搬阻止領域Z1となっている（第１図参照）。この光
伝搬阻止領域Z1は、数μｍのガラスビーズを４〜6kg/cm
2の気圧で数10cmの距離から数10秒間吹き付けて形成し
たものである。A rubber member 15 formed in an annular shape corresponding to the shape of the opening 5a is attached to the front surface of the light emitting case 5. As shown in FIG. 3, the width W of the rubber material 15 is 2-3 m.
m. At the opening of the entire case 4, a frame 16 formed in a square ring by ABS resin is fixed.
A light transmitting plate (outer cover) 17 is attached to the frame 16. As shown in FIG. 4, the light transmitting plate 17 is formed of an acrylic resin in a horizontally long plate shape and is black and transparent. The color is not limited to black and transparent, but may be any color as long as it can transmit the wavelength of the signal being used.
The openings 5a and 6a are covered with the light transmitting plate 17. The portion in contact with the rubber member 15 on the rear surface of the light transmitting plate 17 is formed to be rougher than the other portions, and this portion is a light propagation blocking region Z1 (see FIG. 1). This light propagation blocking region Z1 is made of glass beads of several μm of 4-6 kg / cm.
It is formed by spraying at a pressure of 2 from a distance of several tens of cm for several tens of seconds.
そして、ゴム材15は発光用ケース５と光透過板17との
間で押圧変形された状態となっており、発光用ケース５
とゴム材15、及びゴム材15と光透過板17とは密着してい
る。よって、この部分からレーザダイオード８の光が受
光用ケース６側に洩れることはない。The rubber material 15 is pressed and deformed between the light emitting case 5 and the light transmitting plate 17.
The rubber material 15 and the rubber material 15 and the light transmitting plate 17 are in close contact with each other. Therefore, the light of the laser diode 8 does not leak from this portion to the light receiving case 6 side.
第２図に示すように、演算処理部２は装置本体１の基
板７上の発光回路及び基板11上の受光回路と電気的に接
続され、発光回路に発光指令信号を出力するとともに、
発光回路から発光信号を入力する。又、演算処理部２は
受光回路から受光信号を入力する。As shown in FIG. 2, the arithmetic processing unit 2 is electrically connected to a light emitting circuit on the substrate 7 of the apparatus main body 1 and a light receiving circuit on the substrate 11, and outputs a light emitting command signal to the light emitting circuit.
A light emitting signal is input from a light emitting circuit. Further, the arithmetic processing unit 2 receives a light receiving signal from the light receiving circuit.
次に、このように構成した距離測定装置の作用を説明
する。Next, the operation of the distance measuring apparatus thus configured will be described.
演算処理部２からの発光指令信号により、発光回路は
レーザダイオード８を駆動してパルス状のレーザ光を発
光させるとともに、演算処理部２にレーザの発光に同期
したタイミングで発光信号を出力する。レーザダイオー
ド８のレーザ光は凸レンズ10にて絞られて光透過板17を
通して被対象物に照射される。In response to a light emission command signal from the arithmetic processing unit 2, the light emitting circuit drives the laser diode 8 to emit pulsed laser light, and outputs a light emission signal to the arithmetic processing unit 2 at a timing synchronized with laser emission. The laser light of the laser diode 8 is converged by the convex lens 10 and is irradiated on the object through the light transmitting plate 17.
この時、レーザダイオード８からのレーザ光の一部
が、発光用開口部5aから受光用開口部6a側へ向けて光透
過板17内を全反射しながら伝搬しようとする。この伝搬
光を第１図でL1で示す。しかし、光透過板17の光伝搬阻
止領域Z1により伝搬光L1が乱反射してその伝搬が阻止さ
れる。At this time, a part of the laser light from the laser diode 8 tends to propagate while being totally reflected in the light transmitting plate 17 from the light emitting opening 5a toward the light receiving opening 6a. This propagating light is indicated by L1 in FIG. However, the propagation light L1 is irregularly reflected by the light propagation blocking region Z1 of the light transmission plate 17, and the propagation thereof is blocked.
一方、被対象物にて反射されたレーザ光は光透過板17
を通過してフレネルレンズ14にて集光されてPINフォト
ダイオード12に受光される。そして、この受光に伴って
PINフォトダイオード12から強度に応じた電気信号が出
力され、同信号が受光回路にて増幅される。さらに、増
幅信号が受光回路から演算処理部２に出力される。演算
処理部２では発光回路からの発光信号の入力から受光信
号の入力までの時間を測定して、その時間に基づいて被
対象物までの距離を算出して表示器３に距離信号を送出
する。この距離信号により表示器３にて測定距離が表示
される。On the other hand, the laser beam reflected by the object
, And is condensed by the Fresnel lens 14 and received by the PIN photodiode 12. And with this light reception
An electric signal corresponding to the intensity is output from the PIN photodiode 12, and the signal is amplified by the light receiving circuit. Further, the amplified signal is output from the light receiving circuit to the arithmetic processing unit 2. The arithmetic processing unit 2 measures the time from the input of the light emitting signal to the input of the light receiving signal from the light emitting circuit, calculates the distance to the object based on the time, and sends the distance signal to the display 3. . The measured distance is displayed on the display 3 by the distance signal.
第５図には光透過板17を外した状態での受光波形を示
し、第６図には光透過板17を装着した状態での受光波形
を示し、さらに、第７図には光伝搬阻止領域形成のため
の粗面形成処理を施さない光透過板を装着した状態での
受光波形を示す。これらの図から明らかなように、光伝
搬阻止領域Z1を形成した光透過板17を使用することによ
り、光透過板17内の光伝搬による受光側での影響が性能
上問題とならない程度にまで低減できた。尚、この測定
の際には、被対象物が無限遠方にあるものとした。即
ち、空に向けてレーザ光を照射した。FIG. 5 shows a received light waveform with the light transmitting plate 17 removed, FIG. 6 shows a received light waveform with the light transmitting plate 17 mounted, and FIG. FIG. 9 shows a received light waveform in a state where a light transmitting plate which is not subjected to a rough surface forming process for forming an area is mounted. As is clear from these figures, by using the light transmission plate 17 having the light propagation blocking region Z1, the effect on the light receiving side due to light propagation in the light transmission plate 17 does not cause a problem in performance. Could be reduced. In this measurement, the object was assumed to be at infinity. That is, laser light was irradiated toward the sky.
このように本実施例では、発光用開口部5aと受光用開
口部6aとを覆う光透過板17のゴム材15と接する表面に、
粗面となる光伝搬阻止領域Z1を形成した。つまり、光透
過板17における発光用開口部5aと受光用開口部6aを区切
る領域をその他の部分より粗面とした。その結果、レー
ザダイオード８（発光素子）からの光が発光用開口部5a
から受光用開口部6a側へと光透過板17内を全反射しなが
ら伝搬しようとするが、光透過板17の光伝搬阻止領域Z1
によりその伝搬が阻害され受光用開口部6a側に到ること
が抑制される。このように、STC回路を用いることな
く、簡単な構成にて光透過板17を介してのPINフォトダ
イオード12への光伝搬に起因する障害を回避できる。
又、STC回路はレーザ受光信号を経時的に変化する感度
で検出するため、パルス状の受光信号に歪みが生じ正確
な被対象物までの距離測定を行うことができない虞があ
ったが、本実施例の構造を採用することにより正確に距
離測定を行うことができる。As described above, in this embodiment, the surface of the light transmitting plate 17 that covers the light emitting opening 5a and the light receiving opening 6a in contact with the rubber material 15 is
A light propagation blocking region Z1 that becomes a rough surface was formed. That is, the area of the light transmitting plate 17 that separates the light-emitting opening 5a and the light-receiving opening 6a is made rougher than other parts. As a result, the light from the laser diode 8 (light emitting element) is transmitted to the light emitting opening 5a.
From the light transmission plate 17 to the light receiving opening 6a side while totally reflecting inside the light transmission plate 17, but the light transmission blocking region Z1 of the light transmission plate 17
Accordingly, its propagation is hindered, and reaching the light-receiving opening 6a is suppressed. As described above, it is possible to avoid a trouble due to light propagation to the PIN photodiode 12 via the light transmission plate 17 with a simple configuration without using the STC circuit.
In addition, since the STC circuit detects the laser light reception signal with sensitivity that changes with time, the pulsed light reception signal may be distorted and may not be able to accurately measure the distance to the object. By employing the structure of the embodiment, the distance can be accurately measured.
又、本実施例では光透過板17の光伝搬阻止領域Z1をゴ
ム材15と接する裏面側（後面側）に設けたので美観的に
優れたものとなる。Further, in the present embodiment, since the light propagation blocking region Z1 of the light transmitting plate 17 is provided on the back side (rear side) in contact with the rubber member 15, the appearance is excellent.
尚、この発明は上記実施例に限定されるものではな
く、例えば、光透過板17の粗面となる光伝搬阻止領域Z1
の形成はショット加工の他にも紙やすり等によってその
表面を粗面としてもよい。Note that the present invention is not limited to the above embodiment. For example, the light propagation blocking region Z1 which is a rough surface of the light transmitting plate 17 is provided.
The surface may be roughened by sanding or the like in addition to the shot processing.
さらに、本実施例ではレーザ光を用いた距離測定装置
（レーザレーダ）に具体化したが、他にもレーザ以外の
光を用いたり、受光素子の受光にて被対象物の存在を有
無を検出する装置等の他の反射型光学装置に具体化して
もよい。Furthermore, in this embodiment, the present invention is embodied as a distance measuring device (laser radar) using a laser beam. However, other than using a laser other than a laser or detecting the presence or absence of an object by detecting light using a light receiving element. The present invention may be embodied in another reflection type optical device such as a device for performing the above.
以上詳述したように、この発明によれば、反射型光学
装置を車両に搭載し、光透過板が外部雰囲気の影響を受
けるような環境にて使用するに際し、発光素子及び前記
受光素子が配置される側の表面上にのみ光伝搬阻止領域
を設けたため、外部雰囲気の影響を受けるような環境で
も、光透過板を介しての発光素子から受光素子への光伝
搬を確実に抑制することができる。As described in detail above, according to the present invention, when a reflective optical device is mounted on a vehicle and used in an environment where a light transmitting plate is affected by an external atmosphere, a light emitting element and the light receiving element are arranged. Since the light propagation blocking area is provided only on the surface on the side where light is transmitted, it is possible to reliably suppress light propagation from the light emitting element to the light receiving element through the light transmitting plate even in an environment affected by the external atmosphere. it can.
第１図は実施例の距離測定装置の要部断面図、第２図は
距離測定装置の一部断面図、第３図は第２図のＡ−Ａ断
面図、第４図は光透過板の正面図、第５図〜第７図は図
面に代わるオシロ波形を示す写真である。 ４は全体ケース、５は発光用ケース、5aは発光用開口
部、６は受光用ケース、6aは受光用開口部、８は発光素
子としてのレーダダイオード、12は受光素子としてのPI
Nフォトダイオード、17は光透過板、Z1は光伝搬阻止領
域。1 is a sectional view of a main part of a distance measuring device according to an embodiment, FIG. 2 is a partial sectional view of the distance measuring device, FIG. 3 is a sectional view taken along line AA of FIG. 2, and FIG. 5 to 7 are photographs showing oscilloscope waveforms in place of the drawings. 4 is an overall case, 5 is a light emitting case, 5a is a light emitting opening, 6 is a light receiving case, 6a is a light receiving opening, 8 is a radar diode as a light emitting element, and 12 is a PI as a light receiving element.
N photodiode, 17 is a light transmission plate, and Z1 is a light propagation blocking region.
フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) G01S 7/48 - 7/51 G01S 17/00 - 17/95 G01V 8/00 - 8/26 H01H 35/00 Continuation of the front page (58) Field surveyed (Int.Cl. 6 , DB name) G01S 7/48-7/51 G01S 17/00-17/95 G01V 8/00-8/26 H01H 35/00
Claims (1)
物に向けて照射するための発光用開口部と、 前記発光用開口部の近傍において前記ケースに形成さ
れ、前記被対象物で反射した前記発光素子による光を導
入するための受光用開口部と、 前記ケース内に配置され、前記受光用開口部からの光を
受光する受光素子と、 前記発光用開口部と受光用開口部とを覆い、前記発光素
子及び前記受光素子を外部雰囲気から保護する光透過板
とを備え、 前記光透過板における前記発光用開口部と受光用開口部
を区切る領域で、かつ前記発光素子及び前記受光素子が
配置される側の表面上にのみ光伝搬阻止領域を設けたこ
とを特徴とする車両用反射型光学装置。A light-emitting element disposed in a case; a light-emitting opening formed in the case for irradiating light from the light-emitting element toward an object; and a light-emitting opening. A light-receiving opening formed in the case in the vicinity and for introducing light from the light-emitting element reflected by the object; and a light-receiving opening disposed in the case and receiving light from the light-receiving opening. A light-transmitting plate that covers the light-emitting opening and the light-receiving opening, and protects the light-emitting element and the light-receiving element from an external atmosphere; and the light-emitting opening in the light-transmitting plate and the light-receiving plate. A reflection type optical device for a vehicle, wherein a light propagation blocking region is provided only in a region separating an opening and on a surface on a side where the light emitting element and the light receiving element are arranged.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24156990A JP2995828B2 (en) | 1990-09-11 | 1990-09-11 | Reflective optical device for vehicles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24156990A JP2995828B2 (en) | 1990-09-11 | 1990-09-11 | Reflective optical device for vehicles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04120490A JPH04120490A (en) | 1992-04-21 |
| JP2995828B2 true JP2995828B2 (en) | 1999-12-27 |
Family
ID=17076284
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24156990A Expired - Lifetime JP2995828B2 (en) | 1990-09-11 | 1990-09-11 | Reflective optical device for vehicles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2995828B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7398694B2 (en) * | 2019-06-28 | 2023-12-15 | パナソニックＩｐマネジメント株式会社 | Electronics |
-
1990
- 1990-09-11 JP JP24156990A patent/JP2995828B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04120490A (en) | 1992-04-21 |
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