JP5664512B2 - Radar equipment - Google Patents
Radar equipment Download PDFInfo
- Publication number
- JP5664512B2 JP5664512B2 JP2011209360A JP2011209360A JP5664512B2 JP 5664512 B2 JP5664512 B2 JP 5664512B2 JP 2011209360 A JP2011209360 A JP 2011209360A JP 2011209360 A JP2011209360 A JP 2011209360A JP 5664512 B2 JP5664512 B2 JP 5664512B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- separation element
- polarization separation
- reflected
- unit
- 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.)
- Active
Links
Description
本発明は、光を照射しその反射光を受光することにより、光を反射した物体に関する情報を取得するレーダ装置に関する。 The present invention relates to a radar apparatus that obtains information on an object that reflects light by irradiating light and receiving reflected light.
従来、パルス状のレーザ光を照射し、その反射光を受光することによって、レーザ光を反射した物体との距離や相対速度等、物体に関する情報を取得するレーダ装置が知られている。 2. Description of the Related Art Conventionally, a radar apparatus is known that obtains information about an object such as a distance and a relative speed with respect to an object that reflects the laser light by irradiating pulsed laser light and receiving the reflected light.
この種のレーダ装置において、レーザ光を受光する受光部では、熱雑音等の雑音限界付近の非常に微小な信号を処理するため、ノイズの影響をできるだけ排除する必要がある。一方、レーザ光を発生させる発光部では、光源となる半導体レーザを駆動する際に、瞬時的に大きな電流を流す必要があるため、レーザ光の照射に伴って非常に大きな電磁ノイズが発生する。 In this type of radar apparatus, a light receiving unit that receives laser light processes a very small signal near a noise limit such as thermal noise, and therefore it is necessary to eliminate the influence of noise as much as possible. On the other hand, in a light emitting unit that generates laser light, it is necessary to flow a large current instantaneously when driving a semiconductor laser serving as a light source, and therefore, extremely large electromagnetic noise is generated with irradiation of the laser light.
このような発光部で発生するノイズが受光部に影響を与えることがないようにするために、発光部及び受光部を、個別に金属シールドで覆う等の対策が採られている（例えば、特許文献１参照）。 In order to prevent such noise generated in the light emitting unit from affecting the light receiving unit, measures such as individually covering the light emitting unit and the light receiving unit with a metal shield are taken (for example, patents). Reference 1).
ところで、金属シールドは光も遮蔽するため、金属シールド内の発光部が発生させたレーザ光を、金属シールドの外部に取り出したり、金属シールドの外部から到来するレーザ光を、金属シールド内の受光部に導いたりするために、金属シールドに開口部を設ける必要がある。 By the way, since the metal shield also shields light, the laser light generated by the light emitting part in the metal shield is taken out of the metal shield, or the laser light coming from the outside of the metal shield is received by the light receiving part in the metal shield. It is necessary to provide an opening in the metal shield in order to lead to
しかし、光を通過させるような開口は、通常、ノイズも通り抜けてしまう。このため、装置を小型化するために、発光部及び受光部を接近させて配置した場合には、それぞれが金属シールドで覆われていたとしても、金属シールドの開口部から電磁ノイズが漏洩，侵入することによって、受光部が必要とするＳ／Ｎを確保することができず、ひいては精度のよい測距を行うことができないという問題があった。 However, an aperture through which light passes usually passes through noise. For this reason, in order to reduce the size of the device, when the light emitting unit and the light receiving unit are arranged close to each other, even if each is covered with a metal shield, electromagnetic noise leaks and enters from the opening of the metal shield. As a result, the S / N required by the light receiving unit cannot be secured, and as a result, accurate distance measurement cannot be performed.
本発明は、上記問題点を解決するために、発光部で発生する電磁ノイズが受光部に与える影響を抑制した小型化可能なレーダ装置を提供することを目的とする。 In order to solve the above-described problems, an object of the present invention is to provide a radar device that can be miniaturized in which the influence of electromagnetic noise generated in a light emitting unit on the light receiving unit is suppressed.
上記目的を達成するためになされた発明である請求項１に記載のレーダ装置は、光を照射する発光部と、光を受光する受光部と、予め設定された第１偏光方向の成分の光を透過し、第１偏光方向と直交する第２偏光方向の成分の光を反射することにより、発光部から照射された照射光を、予め設定された投射方向に導くと共に、投射方向から到来する反射光を前記受光部に導く光路変更部とを備えている。 The radar apparatus according to claim 1, which is an invention made to achieve the above object, includes a light emitting unit that emits light, a light receiving unit that receives light, and light of a component in a preset first polarization direction. By reflecting the light of the component of the second polarization direction orthogonal to the first polarization direction, the irradiation light irradiated from the light emitting unit is guided to the preset projection direction and arrives from the projection direction An optical path changing unit for guiding reflected light to the light receiving unit.
そして、光路変更部は、照射光の波長より短い間隔で周期的に配置された金属細線からなる構造体（金属微細周期構造体）を有した偏光分離素子からなり、発光部及び受光部のうち一方が、光を通過させる開口部を有する電磁遮蔽体と、その開口部を塞ぎ且つ構造体が電磁遮蔽体と互いに導通するように設けた偏光分離素子とで形成された電磁遮蔽空間内に配置されている。 The optical path changing unit is composed of a polarization separation element having a structure (metal fine periodic structure) composed of fine metal wires periodically arranged at intervals shorter than the wavelength of the irradiation light. on the other hand but the electromagnetic shielding member having an opening through which light passes, the opening to the electromagnetic shielding in the space formed by the polarization separation element fort technique and structure is provided so as to electrically connected to each other and electromagnetically shield Has been placed.
なお、金属微細周期構造体による偏光分離素子は、必要な光（第１偏光方向の成分の光）を透過しつつ、不要な電磁波に対しては遮蔽体として作用する。
従って、本発明のレーダ装置によれば、電磁遮蔽体と偏光分離素子が形成する電磁遮蔽空間内に発光部が配置されている時には、発光部にて発生した電磁ノイズが電磁遮蔽体の開口部を介して電磁遮蔽空間外に漏洩することを抑制でき、また、電磁遮蔽空間内に受光部が配置されている時には、発光部にて発生した電磁ノイズが電磁遮蔽体の開口部を介して、受光部が配置された電磁遮蔽空間内に侵入することを抑制できる。つまり、発光部にて発生する電磁ノイズに対する受光部での耐性を向上させることができる。
Note that the polarization separation element using the metal fine periodic structure acts as a shield against unnecessary electromagnetic waves while transmitting necessary light (light having a component in the first polarization direction).
Therefore, according to the radar apparatus of the present invention, when the light emitting unit is arranged in the electromagnetic shielding space formed by the electromagnetic shield and the polarization separation element, the electromagnetic noise generated in the light emitting unit is caused by the opening of the electromagnetic shield. Leaking out of the electromagnetic shielding space can be suppressed, and when the light receiving unit is arranged in the electromagnetic shielding space, electromagnetic noise generated in the light emitting unit through the opening of the electromagnetic shielding body, Intrusion into the electromagnetic shielding space in which the light receiving unit is disposed can be suppressed. That is, it is possible to improve resistance at the light receiving unit against electromagnetic noise generated at the light emitting unit.
その結果、本発明のレーダ装置によれば、発光部及び受光部を接近させて配置すること、ひいては装置を小型化することができる。
なお、電磁遮蔽空間内に発光部を配置した場合、発光部，受光部，偏光分離素子は、例えば、請求項２に記載のように、偏光分離素子を透過した照射光の進行方向が投射方向となり、偏光分離素子で反射した反射光を受光部が受光する位置関係となるように配置すればよい。
As a result, according to the radar apparatus of the present invention, the light emitting part and the light receiving part can be arranged close to each other, and the apparatus can be downsized.
When the light emitting unit is arranged in the electromagnetic shielding space, the light emitting unit, the light receiving unit, and the polarization separation element are, for example, as claimed in claim 2, wherein the traveling direction of the irradiation light transmitted through the polarization separation element is the projection direction. Therefore, the reflection light reflected by the polarization separation element may be arranged so as to be in a positional relationship where the light receiving unit receives light.
また、電磁遮蔽空間内に受光部を配置した場合、発光部，受光部，偏光分離素子は、例えば、請求項３に記載のように、偏光分離素子で反射した照射光の進行方向が投射方向となり、偏光分離素子を透過した反射光を、受光部が受光する位置関係となるように配置すればよい。 In addition, when the light receiving unit is disposed in the electromagnetic shielding space, the light emitting unit, the light receiving unit, and the polarization separation element, for example, as in claim 3, the traveling direction of the irradiation light reflected by the polarization separation element is the projection direction. Therefore, the reflected light transmitted through the polarization separation element may be arranged so as to be in a positional relationship where the light receiving unit receives light.
ところで、反射光のうち、物体で鏡面反射した成分については、偏光方向が照射光と同じ状態に保持される。このような鏡面反射による反射光の成分は、偏光分離素子によって発光部側に戻されることになる。 By the way, the component of the reflected light that is specularly reflected by the object is kept in the same polarization direction as the irradiation light. The component of the reflected light due to such specular reflection is returned to the light emitting unit side by the polarization separation element.
そこで、請求項２又は請求項３に記載のレーダ装置では、請求項４に記載のように、偏光分離素子から投射方向に向かう照射光及び投射方向から到来し偏光分離素子に向かう反射光が通過する経路上に１／４波長板を設けることが望ましい。 Therefore, in the radar device according to claim 2 or claim 3, as described in claim 4, the irradiation light traveling from the polarization separation element toward the projection direction and the reflected light coming from the projection direction toward the polarization separation element pass through. It is desirable to provide a quarter wave plate on the path to be used.
このように構成された本発明のレーダ装置では、偏光分離素子から物体に到達する前と、物体から偏光分離素子に到達する前の２回、１／４波長板を通過する。その結果、鏡面反射して偏光分離素子に入射する反射光は、偏光分離素子を透過した照射光とは偏光方向が９０°異なったものとなり、その殆どが偏光分離素子にて反射するため、反射光を効率よく受光部に導くことができる。 In the radar apparatus of the present invention configured as described above, the light passes through the quarter wavelength plate twice before reaching the object from the polarization separation element and before reaching the polarization separation element from the object. As a result, the reflected light that is specularly reflected and incident on the polarization separation element has a polarization direction that differs by 90 ° from the irradiation light that has passed through the polarization separation element, and most of the reflected light is reflected by the polarization separation element. Light can be efficiently guided to the light receiving unit.
また、請求項２乃至請求項４のいずれか一項に記載のレーダ装置は、請求項５に記載のように、偏光分離素子によって投射方向に導かれた照射光の進行方向を変化させることにより、予め設定された走査角度範囲内を走査する第１走査手段を備えていてもよい。 The radar apparatus according to any one of claims 2 to 4 can change the traveling direction of the irradiation light guided in the projection direction by the polarization separation element as described in claim 5. A first scanning unit that scans within a preset scanning angle range may be provided.
このように構成された本発明のレーダ装置によれば、物体の検知範囲を広げることができる。
請求項３に記載のレーダ装置では、請求項６に記載のように、更に、偏光分離素子を透過した反射光を、該反射光の入射方向に向けて反射する反射素子と、偏光分離素子と反射素子との間に設けられた１／４波長板とを備えていてもよい。この場合、受光部は、反射素子にて反射され１／４波長板を通過して到来する反射光を再帰反射光として、偏光分離素子で反射した再帰反射光を受光する位置に設けられていればよい。
According to the radar apparatus of the present invention configured as described above, the object detection range can be expanded.
In the radar apparatus according to claim 3, as described in claim 6, a reflection element that reflects the reflected light transmitted through the polarization separation element toward an incident direction of the reflection light, a polarization separation element, and You may provide the quarter wavelength plate provided between reflection elements. In this case, the light receiving unit is provided at a position for receiving the retroreflected light reflected by the polarization separation element using the reflected light reflected by the reflective element and passing through the quarter-wave plate as the retroreflected light. That's fine.
また、請求項６に記載のレーダ装置では、更に、請求項７に記載のように、予め設定された所定回転軸を中心に偏光分離素子を回動させることで、偏光分離素子で反射する照射光の進行方向を変化させることにより、予め設定された走査角度範囲内を走査する第２走査手段を備えていてもよい。 Further, in the radar apparatus according to claim 6, as described in claim 7, the irradiation reflected by the polarization separation element by rotating the polarization separation element about a predetermined rotation axis set in advance. You may provide the 2nd scanning means which scans within the preset scanning angle range by changing the advancing direction of light.
この場合、偏光分離素子を動作させることで走査が実現されるため、走査に必要な構成を簡略化することができる。 In this case, since the scanning is realized by operating the polarization separation element, the configuration necessary for the scanning can be simplified.
以下に本発明の実施形態を図面と共に説明する。
［第１実施形態］
＜全体構成＞
図１は、本実施形態のレーダ装置１の構成及び動作を示す説明図である。
Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
<Overall configuration>
FIG. 1 is an explanatory diagram showing the configuration and operation of the radar apparatus 1 of the present embodiment.
図１に示すように、レーダ装置１は、レーザダイオード等の発光素子を駆動してパルス状のレーザ光を発生させる発光部１０と、発光部１０から照射されたレーザ光を平行光にして投射する投光光学系１１と、フォトダイオード等の受光素子によりレーザ光を受光する受光部１２と、所定方向から到来するレーザ光を収束させて受光部１２に導く受光光学系１３と、投光光学系１１を介して投射されるレーザ光（以下「照射光」という）を透過すると共に、その照射光の投射方向から到来するレーザ光（以下「反射光」という）を反射して受光光学系１３に向かうように光路を屈曲させる光路変更部１４と、光路変更部１４を透過した照射光及び光路変更部１４に向かう反射光の光路上に設けられた１／４波長板１５と、１／４波長板１５を通過した照射光を反射し、その反射角度を変化させることにより、予め設定された走査範囲内で照射光を走査する共に、走査範囲内から到来するレーザ光を１／４波長板１５を介して光路変更部１４に導く走査部１６とを備えている。 As shown in FIG. 1, a radar apparatus 1 projects a light emitting unit 10 that generates a pulsed laser beam by driving a light emitting element such as a laser diode, and a laser beam emitted from the light emitting unit 10 as parallel light. A light projecting optical system 11, a light receiving unit 12 that receives laser light by a light receiving element such as a photodiode, a light receiving optical system 13 that converges laser light coming from a predetermined direction and guides it to the light receiving unit 12, and light projecting optics Laser light (hereinafter referred to as “irradiated light”) projected through the system 11 is transmitted, and laser light (hereinafter referred to as “reflected light”) coming from the projection direction of the irradiated light is reflected to receive the light receiving optical system 13. An optical path changing unit 14 that bends the optical path toward the optical path, a quarter-wave plate 15 provided on the optical path of the irradiation light transmitted through the optical path changing unit 14 and the reflected light toward the optical path changing unit 14, and 1/4 Wave plate 15 By reflecting the excess irradiation light and changing the reflection angle, the irradiation light is scanned within the preset scanning range, and the laser light coming from within the scanning range is passed through the quarter wavelength plate 15. And a scanning unit 16 that leads to the optical path changing unit 14.
なお、１／４波長板１５は、直線偏光を円偏光に変換するとともに円偏光を直線偏光に変換する機能を有した周知のものである。また、走査部１６は、ＭＥＭＳ、ガルバノ等より構成された周知のものである。 The quarter wavelength plate 15 is a well-known one having a function of converting linearly polarized light into circularly polarized light and converting circularly polarized light into linearly polarized light. Further, the scanning unit 16 is a well-known unit configured by MEMS, galvano, or the like.
ここで、図２は、（ｂ）が光路変更部１４の平面図、（ａ）がそのＡ−Ａ断面図である。
図２に示すように、光路変更部１４は、レーザ光を透過可能な材料で形成された板形状の基板１４１と、偏光分離機能を有する構造となるように基板１４１の面上に形成された偏光分離構造体１４２とで構成されたいわゆる偏光分離素子からなる。以下では、光路変更部１４を偏光分離素子１４ともいう。
Here, FIG. 2B is a plan view of the optical path changing unit 14 and FIG.
As shown in FIG. 2, the optical path changing unit 14 is formed on the surface of the substrate 141 so as to have a plate-shaped substrate 141 made of a material capable of transmitting laser light and a structure having a polarization separation function. It consists of a so-called polarization separation element composed of the polarization separation structure 142. Hereinafter, the optical path changing unit 14 is also referred to as a polarization separation element 14.
なお、偏光分離構造体１４２は、導電性材料（例えば、Ａｌ，Ａｕ，Ａｇ，Ｃｕ等）により形成された複数の金属細線を、発光部１０から照射されるレーザ光の波長よりも短い間隔で予め設定された方向（以下、格子方向という）に沿って平行に配置することにより構成された格子状の構造（ワイヤグリッド）を有する。このような微細な周期構造体は、周知の微細加工技術を用いることで形成することができる。 The polarization separation structure 142 has a plurality of fine metal wires formed of a conductive material (for example, Al, Au, Ag, Cu, etc.) at intervals shorter than the wavelength of the laser light emitted from the light emitting unit 10. It has a lattice-like structure (wire grid) configured by arranging in parallel along a preset direction (hereinafter referred to as a lattice direction). Such a fine periodic structure can be formed by using a well-known fine processing technique.
図１に戻り、偏光分離素子１４，１／４波長板１５は、投光光学系１１から投射され直進するレーザ光が走査部１６に至る光路（以下、照射光路という）上に位置し、しかも、偏光分離素子１４及び１／４波長板１５の略中心位置にレーザ光の光軸が位置するように配置されている。但し、偏光分離素子１４は、照射光路に対して４５°傾斜し、１／４波長板１５は照射光路に対して正対するように配置されている。また、レーザダイオードによって発生させたレーザ光は偏光しているため、レーザ光の偏光方向と偏光分離素子１４の格子方向とが一致するように偏光分離素子１４は配置される。 Returning to FIG. 1, the polarization separation element 14 and the quarter-wave plate 15 are positioned on an optical path (hereinafter referred to as an irradiation optical path) where the laser light projected from the light projecting optical system 11 and travels straight reaches the scanning unit 16. In addition, the optical axis of the laser beam is arranged at substantially the center position of the polarization separating element 14 and the quarter wavelength plate 15. However, the polarization separation element 14 is inclined by 45 ° with respect to the irradiation light path, and the quarter-wave plate 15 is disposed so as to face the irradiation light path. In addition, since the laser light generated by the laser diode is polarized, the polarization separation element 14 is arranged so that the polarization direction of the laser light and the grating direction of the polarization separation element 14 coincide.
また、受光光学系１３及び受光部１２は、照射光路に対して直交し、且つ、偏光分離素子１４の中心位置を通る軸（即ち、走査部１６から偏光分離素子１４に向かい、偏光分離素子１４で反射したレーザ光の光軸）上に位置するように配置されている。 The light receiving optical system 13 and the light receiving unit 12 are orthogonal to the irradiation optical path and pass through the center position of the polarization separation element 14 (that is, from the scanning unit 16 toward the polarization separation element 14 and toward the polarization separation element 14). Are arranged so as to be located on the optical axis of the laser beam reflected by the laser beam.
そして、発光部１０及び投光光学系１１は、金属製の発光部シールド１７に収納されており、その発光部シールド１７には、発光部１０が発生させたレーザ光を発光部シールド１７の外部に取り出すための開口部が設けられ、更に、その開口部を塞ぐように、偏光分離素子１４が設置されている。但し、発光部シールド１７と偏光分離素子１４の偏光分離構造体１４２とは互いに導通するように接続され共通のグランドに接地されている。つまり、発光部１０及び投光光学系１１は、発光部シールド１７と偏光分離素子１４とが形成する電磁遮蔽空間内に配置されるように構成されている。 The light emitting unit 10 and the light projecting optical system 11 are housed in a metal light emitting unit shield 17. The light emitting unit shield 17 receives laser light generated by the light emitting unit 10 outside the light emitting unit shield 17. An opening for taking out the light is provided, and a polarization separation element 14 is installed so as to close the opening. However, the light-emitting portion shield 17 and the polarization separation structure 142 of the polarization separation element 14 are connected to each other and grounded to a common ground. That is, the light emitting unit 10 and the light projecting optical system 11 are configured to be disposed in an electromagnetic shielding space formed by the light emitting unit shield 17 and the polarization separation element 14.
一方、受光部１２は、金属製の受光部シールド１８に収納されており、その受光部シールド１８には、レーザ光を受光部シールド１８内の受光部１２に導くための開口部が設けられ、更に、その開口部を塞ぐように、受光光学系１３を形成するレンズが設置されている。 On the other hand, the light receiving unit 12 is housed in a metal light receiving unit shield 18, and the light receiving unit shield 18 is provided with an opening for guiding laser light to the light receiving unit 12 in the light receiving unit shield 18. Further, a lens forming the light receiving optical system 13 is installed so as to close the opening.
＜動作＞
次に、このように構成されたレーダ装置１の動作を説明する。
まず、発光部１０から照射されたレーザ光（以下、照射光という）は、投光光学系１１により略平行光に変換され偏光分離素子１４に到達する（光Ｌ１１を参照）。偏光分離素子１４に到達した照射光のうち、上記格子方向に平行な偏光方向を有する成分（ＴＭ成分）は、偏光分離素子１４を透過し（光Ｌ１２を参照）、１／４波長板１５を通過して走査部１６に到達する（光Ｌ１３を参照）。なお、１／４波長板１５を通過した照射光は直線偏光から円偏光に変換される。
<Operation>
Next, the operation of the radar apparatus 1 configured as described above will be described.
First, laser light (hereinafter referred to as irradiation light) emitted from the light emitting unit 10 is converted into substantially parallel light by the light projecting optical system 11 and reaches the polarization separation element 14 (see the light L11). Of the irradiated light that has reached the polarization separation element 14, a component having a polarization direction parallel to the grating direction (TM component) is transmitted through the polarization separation element 14 (see the light L <b> 12) and passes through the quarter wavelength plate 15. It passes through and reaches the scanning unit 16 (see the light L13). The irradiation light that has passed through the quarter-wave plate 15 is converted from linearly polarized light to circularly polarized light.
そして、走査部１６に到達した照射光は、走査部１６の動作に従って走査角度範囲内にレーダ波として照射される（光Ｌ１４を参照）。
その後、物体Ｂで反射し入射方向に戻ってくるレーザ光（以下、反射光という）は、走査部１６により照射光の到来方向に導かれる（光Ｌ１５，Ｌ１６を参照）。この走査部１６に導かれた反射光は、１／４波長板１５を通過して偏光分離素子１４に到達する（光Ｌ１７を参照）。なお、１／４波長板１５を通過して偏光分離素子１４に到達する反射光は、円偏光から直線偏光に変換され、しかも、偏光分離素子１４を通過した照射光とは偏向方向が９０°異なったもの（ＴＥ成分）となる。
And the irradiation light which reached | attained the scanning part 16 is irradiated as a radar wave within a scanning angle range according to the operation | movement of the scanning part 16 (refer light L14).
Thereafter, laser light reflected by the object B and returning to the incident direction (hereinafter referred to as reflected light) is guided by the scanning unit 16 in the arrival direction of the irradiation light (see the lights L15 and L16). The reflected light guided to the scanning unit 16 passes through the quarter wavelength plate 15 and reaches the polarization separating element 14 (see the light L17). The reflected light that passes through the quarter-wave plate 15 and reaches the polarization separation element 14 is converted from circularly polarized light to linearly polarized light, and the deflection direction is 90 ° with respect to the irradiation light that has passed through the polarization separation element 14. Different one (TE component).
このため、１／４波長板１５を通過した反射光は、偏光分離素子１４で反射して受光光学系１３に導かれる。この反射光は、受光光学系１３で収束され受光部１２に到達して、受光部１２にて受光信号に光電変換される（光Ｌ１８を参照）。 Therefore, the reflected light that has passed through the quarter wavelength plate 15 is reflected by the polarization separation element 14 and guided to the light receiving optical system 13. The reflected light is converged by the light receiving optical system 13 and reaches the light receiving unit 12, and is photoelectrically converted into a light reception signal by the light receiving unit 12 (see the light L18).
そして、レーダ装置１では、この受光信号に基づき、図示しない信号処理部にて、発光部１０がパルスレーザ光を照射した時刻と、受光部１２が反射光を受光した時刻との差を計測し、その計測結果から、レーザ光を反射した物体までの距離が求められることになる。 In the radar apparatus 1, based on this light reception signal, a signal processing unit (not shown) measures the difference between the time when the light emitting unit 10 emits the pulsed laser light and the time when the light receiving unit 12 receives the reflected light. From the measurement result, the distance to the object reflecting the laser beam is obtained.
＜効果＞
以上説明したようにレーダ装置１によれば、発光部１０が発光部シールド１７及び偏光分離素子１４が形成する電磁遮蔽空間内に配置されているため、発光部１０がレーザ光を照射する時に発生させる電磁ノイズが、発光部シールド１７の開口部から外部に漏洩することを抑制することができる。
<Effect>
As described above, according to the radar apparatus 1, since the light emitting unit 10 is disposed in the electromagnetic shielding space formed by the light emitting unit shield 17 and the polarization separation element 14, it occurs when the light emitting unit 10 emits laser light. It is possible to suppress leakage of electromagnetic noise to the outside from the opening of the light emitting unit shield 17.
つまり、発光部１０にて発生し、受光部１２に干渉する電磁ノイズの影響を低減することができるため、発光部１０と受光部１２とを接近配置させて装置を小型化しても、電磁ノイズの影響の少ない受光信号を得ること、ひいては正常な測距を行うことができる。 That is, since the influence of electromagnetic noise generated at the light emitting unit 10 and interfering with the light receiving unit 12 can be reduced, even if the light emitting unit 10 and the light receiving unit 12 are arranged close to each other to reduce the size of the apparatus, the electromagnetic noise is reduced. It is possible to obtain a received light signal that is less affected by this, and thus to perform normal distance measurement.
なお、本実施形態において、金属シールド１７，１８が電磁遮蔽体、走査部１６が第１走査手段、レーザ光のＴＭ成分が第１偏光方向の成分、ＴＥ成分が第２偏光方向の成分に相当する。 In the present embodiment, the metal shields 17 and 18 are electromagnetic shields, the scanning unit 16 is the first scanning means, the TM component of the laser light is a component in the first polarization direction, and the TE component is a component in the second polarization direction. To do.
［第２実施形態］
次に、第２実施形態について説明する。
＜全体構成＞
図３は、本実施形態のレーダ装置２の構成及び動作を示す説明図である。
[Second Embodiment]
Next, a second embodiment will be described.
<Overall configuration>
FIG. 3 is an explanatory diagram showing the configuration and operation of the radar apparatus 2 of the present embodiment.
図３に示すように、レーダ装置２は、レーダ装置１における発光部１０，投光光学系１１，受光部１２，受光光学系１３，偏光分離素子１４，１／４波長板１５，走査部１６と同様に構成された発光部２０，投光光学系２１，受光部２２，受光光学系２３，偏光分離素子２４（基板２４１，偏光分離構造体２４２），１／４波長板２５，走査部２６を備えている。 As shown in FIG. 3, the radar device 2 includes a light emitting unit 10, a light projecting optical system 11, a light receiving unit 12, a light receiving optical system 13, a polarization separating element 14, a quarter wavelength plate 15, and a scanning unit 16 in the radar device 1. The light emitting unit 20, the light projecting optical system 21, the light receiving unit 22, the light receiving optical system 23, the polarization separation element 24 (the substrate 241, the polarization separation structure 242), the quarter wavelength plate 25, and the scanning unit 26 configured in the same manner as in FIG. It has.
但し、レーダ装置２では、レーダ装置１の場合とは異なり、投光光学系２１から偏光分離素子２４に向かう照射光の偏光方向が偏光分離素子２４の格子方向と直交するように配置されている。 However, unlike the radar apparatus 1, the radar apparatus 2 is arranged so that the polarization direction of the irradiation light from the light projecting optical system 21 toward the polarization separation element 24 is orthogonal to the grating direction of the polarization separation element 24. .
また、偏光分離素子２４，１／４波長板２５は、走査部２６から戻ってくるレーザ光（反射光）が受光光学系２３に至る直線の光路（以下、反射光路という）上に位置し、しかも、偏光分離素子２４及び１／４波長板２５の略中心位置にレーザ光の光軸が位置するように配置されている。但し、偏光分離素子２４は、反射光路に対して４５°傾斜し、１／４波長板２５は反射光路に対して正対するように配置されている。 The polarization separation element 24 and the quarter wavelength plate 25 are positioned on a linear optical path (hereinafter referred to as a reflected optical path) where the laser light (reflected light) returning from the scanning unit 26 reaches the light receiving optical system 23. In addition, the optical axis of the laser beam is arranged at substantially the center position of the polarization separation element 24 and the quarter wavelength plate 25. However, the polarization separation element 24 is inclined by 45 ° with respect to the reflected light path, and the quarter-wave plate 25 is disposed so as to face the reflected light path.
更に、発光部２０及び投光光学系２１は、投光光学系２１から照射された照射光の光軸が反射光路に対して直交し、且つ、偏光分離素子２４の中心位置を通るように配置され、偏光分離素子２４で反射した照射光が導かれる投射方向が、反射光路を逆行する方向となるように配置されている。 Further, the light emitting unit 20 and the light projecting optical system 21 are arranged so that the optical axis of the irradiated light emitted from the light projecting optical system 21 is orthogonal to the reflected light path and passes through the center position of the polarization separation element 24. Then, the projection direction in which the irradiation light reflected by the polarization separation element 24 is guided is arranged to be a direction reverse to the reflected light path.
そして、発光部２０は、金属製の発光部シールド２７に収納されており、その発光部シールド２７には、発光部２０から照射されたレーザ光を発光部シールド２７の外部に取り出すための開口部が設けられ、更に、その開口部を塞ぐように、投光光学系２１を形成するレンズが設置されている。 The light emitting unit 20 is housed in a metal light emitting unit shield 27. The light emitting unit shield 27 has an opening for taking out the laser light emitted from the light emitting unit 20 to the outside of the light emitting unit shield 27. Further, a lens for forming the light projecting optical system 21 is installed so as to close the opening.
一方、受光部２２及び受光光学系２３は、金属製の受光部シールド２８に収納されており、その受光部シールド２８には、レーザ光を受光部シールド２８内の受光光学系２３に導くための開口部が設けられ、更に、その開口部を塞ぐように、偏光分離素子２４が設置されている。但し、受光部シールド２８と偏光分離素子２４の偏光分離構造体２４２とは互いに導通するように接続され、共通のグランドに接地されている。つまり、受光部２２は、受光部シールド２８と偏光分離素子２４とが形成する電磁遮蔽空間内に配置されるように構成されている。 On the other hand, the light receiving unit 22 and the light receiving optical system 23 are housed in a metal light receiving unit shield 28, and the light receiving unit shield 28 guides laser light to the light receiving optical system 23 in the light receiving unit shield 28. An opening is provided, and a polarization separation element 24 is further installed so as to close the opening. However, the light-receiving unit shield 28 and the polarization separation structure 242 of the polarization separation element 24 are connected to each other and grounded to a common ground. That is, the light receiving unit 22 is configured to be disposed in an electromagnetic shielding space formed by the light receiving unit shield 28 and the polarization separation element 24.
＜動作＞
次に、このように構成されたレーダ装置２の動作を説明する。
まず、発光部２０から照射されたレーザ光（照射光）は、投光光学系２１により略平行光に変換され偏光分離素子２４に到達する（光Ｌ２１を参照）。偏光分離素子２４に到達した照射光のうち、上記格子方向に直行した偏光方向を有する成分（ＴＥ成分）は、偏光分離素子１４で反射することで光路が略９０°変化し１／４波長板２５に入射する（光Ｌ２２を参照）。なお、発光部２０から照射される照射光は偏光しているため、偏光分離素子２４の偏光方向と照射光の偏光方向が直行するように適切に配置することによって、殆どの照射光を偏光分離素子２４で反射させることができる。
<Operation>
Next, the operation of the radar apparatus 2 configured as described above will be described.
First, the laser light (irradiation light) emitted from the light emitting unit 20 is converted into substantially parallel light by the light projecting optical system 21 and reaches the polarization separation element 24 (see the light L21). Of the irradiation light that has reached the polarization separation element 24, a component (TE component) having a polarization direction orthogonal to the grating direction is reflected by the polarization separation element 14 to change the optical path by approximately 90 °, and a quarter-wave plate. 25 (see light L22). Since the irradiation light emitted from the light emitting unit 20 is polarized, most of the irradiation light is polarized and separated by properly arranging the polarization direction of the polarization separation element 24 and the polarization direction of the irradiation light to be orthogonal to each other. It can be reflected by the element 24.
１／４波長板２５に入射された照射光は、直線偏光から円偏光に変換されて走査部１６に到達する（光Ｌ２３を参照）。走査部２６に到達した照射光は、走査部２６の動作に従って走査角度範囲内にレーダ波として照射される（光Ｌ２４を参照）。 The irradiation light incident on the quarter-wave plate 25 is converted from linearly polarized light to circularly polarized light and reaches the scanning unit 16 (see the light L23). The irradiation light that has reached the scanning unit 26 is irradiated as a radar wave within a scanning angle range in accordance with the operation of the scanning unit 26 (see the light L24).
走査角度範囲内に存在する物体Ｂで反射し入射方向とは逆方向に戻ってくるレーザ光（反射光）は、走査部２６により照射光の到来方向に導かれる（光Ｌ２５，Ｌ２６を参照）。この走査部２６によって導かれた反射光は、１／４波長板２５を通過することで、円偏波から直線偏光に変換されて偏光分離素子２４に到達する（光Ｌ２７を参照）。なお、１／４波長板２５にて円偏光から直線偏光に変換された反射光は、１／４波長板２５に入射する直線偏光の照射光とは偏光方向が９０°異なったもの（ＴＭ成分）となる。 The laser beam (reflected light) reflected by the object B existing within the scanning angle range and returning in the direction opposite to the incident direction is guided by the scanning unit 26 in the direction of arrival of the irradiation light (see the light L25 and L26). . The reflected light guided by the scanning unit 26 passes through the quarter-wave plate 25, is converted from circularly polarized light to linearly polarized light, and reaches the polarization separation element 24 (see the light L27). The reflected light converted from circularly polarized light to linearly polarized light by the quarter wavelength plate 25 has a polarization direction different from that of the linearly polarized light incident on the quarter wavelength plate 25 (TM component). )
このため、１／４波長板２５を通過した反射光は、偏光分離素子２４で反射して受光光学系２３に導かれる。この受光光学系２３に導かれた反射光は、受光光学系１３で収束して受光部２２に到達して、受光部２２にて受光信号に光電変換される（光Ｌ２８を参照）。 Therefore, the reflected light that has passed through the quarter-wave plate 25 is reflected by the polarization separation element 24 and guided to the light receiving optical system 23. The reflected light guided to the light receiving optical system 23 is converged by the light receiving optical system 13 to reach the light receiving unit 22 and is photoelectrically converted into a light receiving signal by the light receiving unit 22 (see the light L28).
そして、レーダ装置２では、この受光信号に基づき、図示しない信号処理部にて、発光部２０がパルスレーザ光を照射した時刻と、受光部２２が反射光を受光した時刻との差を計測し、その計測結果から、レーザ光を反射した物体までの距離が求められることになる。 The radar device 2 measures the difference between the time when the light emitting unit 20 radiates the pulse laser beam and the time when the light receiving unit 22 receives the reflected light based on the light reception signal. From the measurement result, the distance to the object reflecting the laser beam is obtained.
なお、レーザ光が物体Ｂにて鏡面反射した成分については、偏光の向きが保存されるため、１／４波長板２５の作用によって、その殆どを受光部２２に導くことができるが、物体Ｂにて散乱反射した成分については、約半分が受光部２２に導かれることになる。 The component of the laser beam that is specularly reflected by the object B can be mostly guided to the light receiving unit 22 by the action of the quarter-wave plate 25 because the polarization direction is preserved. About half of the components scattered and reflected by the light are guided to the light receiving unit 22.
＜効果＞
このように構成されたレーダ装置２によれば、受光部２２が受光部シールド２８及び偏光分離素子２４が形成する電磁遮蔽空間内に配置されているため、レーザ光の照射時に発光部２０にて発生した電磁ノイズが、反射光を取り込むために設けられた受光部シールド２８の開口部から（即ち偏光分離素子２４を介して）侵入することを抑制することができる。
<Effect>
According to the radar apparatus 2 configured as described above, the light receiving unit 22 is disposed in the electromagnetic shielding space formed by the light receiving unit shield 28 and the polarization separation element 24, so that the light emitting unit 20 performs the irradiation with the laser light. It is possible to suppress the generated electromagnetic noise from entering from the opening of the light receiving portion shield 28 provided for taking in the reflected light (that is, via the polarization separation element 24).
つまり、発光部２０にて発生し、受光部２２に干渉する電磁ノイズの影響を低減することができるため、発光部２０と受光部２２とを接近配置させて装置を小型化しても、電磁ノイズの影響の少ない受光信号を得ること、ひいては、正常な測距を行うことができる。 That is, since the influence of electromagnetic noise generated in the light emitting unit 20 and interfering with the light receiving unit 22 can be reduced, even if the light emitting unit 20 and the light receiving unit 22 are arranged close to each other and the apparatus is downsized, the electromagnetic noise is reduced. It is possible to obtain a received light signal that is less influenced by the above-mentioned, and thus to perform normal distance measurement.
［第３実施形態］
次に、第３実施形態について説明する。
＜全体構成＞
図４は、本実施形態のレーダ装置３の構成及び動作を示す説明図である。
[Third Embodiment]
Next, a third embodiment will be described.
<Overall configuration>
FIG. 4 is an explanatory diagram showing the configuration and operation of the radar apparatus 3 of the present embodiment.
図４に示すように、レーダ装置３は、レーダ装置１における、発光部１０，投光光学系１１，受光部１２，受光光学系１３，偏光分離素子１４，１／４波長板１５と同様に構成された発光部３０，投光光学系３１，受光部３２，受光光学系３３，偏光分離素子３４（基板３４１，偏光分離構造体３４２），１／４波長板３５を備えている。 As shown in FIG. 4, the radar device 3 is similar to the light emitting unit 10, the light projecting optical system 11, the light receiving unit 12, the light receiving optical system 13, the polarization separating element 14, and the quarter wavelength plate 15 in the radar device 1. The light emitting unit 30, the light projecting optical system 31, the light receiving unit 32, the light receiving optical system 33, the polarization separation element 34 (the substrate 341, the polarization separation structure 342), and the quarter wavelength plate 35 are provided.
但し、レーダ装置３では、レーダ装置１の場合とは異なり、照射光の偏光方向が偏光分離素子１４の格子方向と直交するように配置される。また、投光光学系３１及び受光光学系３３は、偏光分離素子３４を挟んで対向する位置に設けられ、偏光分離素子３４の偏光分離構造体３４２側の面に照射光が投射され、基板３４１側の面で反射した反射光が受光光学系３３を介して受光部３２に導かれるように配置されている。 However, unlike the radar apparatus 1, the radar apparatus 3 is arranged so that the polarization direction of the irradiation light is orthogonal to the grating direction of the polarization separation element 14. Further, the light projecting optical system 31 and the light receiving optical system 33 are provided at positions facing each other with the polarization separation element 34 interposed therebetween, and irradiation light is projected onto the surface of the polarization separation element 34 on the side of the polarization separation structure 342, so that the substrate 341 is provided. The light reflected by the side surface is arranged so as to be guided to the light receiving unit 32 via the light receiving optical system 33.
また、偏光分離素子３４は、中心軸を介して回動可能に支持され、図示しない駆動装置により、投光光学系３１から入射するレーザ光の光軸に対して４５°傾斜した角度を中心として設定された所定角度範囲内で角度を変化させることができるように構成されている。 The polarization separation element 34 is rotatably supported through a central axis, and is centered on an angle inclined by 45 ° with respect to the optical axis of the laser light incident from the light projecting optical system 31 by a driving device (not shown). The angle can be changed within a set predetermined angle range.
そして、偏光分離素子３４で反射した照射光が照射される範囲を走査範囲として、１／４波長板３５は、偏光分離素子３４を挟んで走査範囲と対向する位置に配置されている。
更にレーダ装置３は、１／４波長板３５を透過したレーザ光を、その入射方向とは逆方向に反射する機能を有した再帰性反射素子３６を備えている。なお、再帰性反射素子３６は、素子本体となる基板の表面に、例えばコーナーキューブアレイ、ビーズアレイ、及びプリズムアレイのいずれかを形成することにより構成される。
The ¼ wavelength plate 35 is disposed at a position facing the scanning range with the polarization separation element 34 interposed therebetween, with the range in which the irradiation light reflected by the polarization separation element 34 is irradiated as a scanning range.
Further, the radar apparatus 3 includes a retroreflective element 36 having a function of reflecting the laser light transmitted through the quarter wavelength plate 35 in the direction opposite to the incident direction. The retroreflective element 36 is configured by forming, for example, any one of a corner cube array, a bead array, and a prism array on the surface of a substrate serving as an element body.
また、発光部３０は、金属製の発光部シールド３７に収納されており、その発光部シールド３７には、発光部３０から照射されたレーザ光を発光部シールド３７の外部に取り出すための開口部が設けられ、更に、その開口部を塞ぐように、投光光学系３１を形成するレンズが設置されている。 The light emitting unit 30 is housed in a metal light emitting unit shield 37. The light emitting unit shield 37 has an opening for taking out the laser light emitted from the light emitting unit 30 to the outside of the light emitting unit shield 37. Further, a lens that forms the light projecting optical system 31 is installed so as to close the opening.
一方、受光部３２及び受光光学系３３，１／４波長板３５，再帰性反射素子３６は、金属製の受光部シールド３８に収納されており、その受光部シールド３８には、レーザ光を受光部シールド２８内の受光光学系２３に導くための開口部が設けられ、更に、その開口部を塞ぐように偏光分離素子３４が設置されている。但し、受光部シールド３８と偏光分離素子３４の偏光分離構造体３４２とは互いに導通するように接続され、共通のグランドに接地されている。つまり、受光部３２は、受光部シールド３８と偏光分離素子３４とが形成する電磁遮蔽空間内に配置されるように構成されている。 On the other hand, the light receiving unit 32, the light receiving optical system 33, the quarter wavelength plate 35, and the retroreflective element 36 are housed in a metal light receiving unit shield 38, and the light receiving unit shield 38 receives laser light. An opening for guiding the light receiving optical system 23 in the part shield 28 is provided, and a polarization separation element 34 is further installed so as to close the opening. However, the light receiving unit shield 38 and the polarization separation structure 342 of the polarization separation element 34 are connected to each other and are grounded to a common ground. In other words, the light receiving unit 32 is configured to be disposed in an electromagnetic shielding space formed by the light receiving unit shield 38 and the polarization separation element 34.
＜動作＞
次に、このように構成されたレーダ装置３の動作を説明する。
まず、発光部３０から照射されたレーザ光（照射光）は、投光光学系３１により略平行光に変換され偏光分離素子３４に到達する（光Ｌ３１を参照）。偏光分離素子３４に到達した照射光のうち、格子方向に直行した偏光方向を有する成分（ＴＥ成分）は、偏光分離素子３４で反射することで光路が変化し、走査範囲に向けて照射される（光Ｌ３２を参照）。
<Operation>
Next, the operation of the radar apparatus 3 configured as described above will be described.
First, the laser light (irradiation light) emitted from the light emitting unit 30 is converted into substantially parallel light by the light projecting optical system 31 and reaches the polarization separation element 34 (see the light L31). Of the irradiation light that has reached the polarization separation element 34, a component (TE component) having a polarization direction orthogonal to the grating direction is reflected by the polarization separation element 34, and its optical path is changed to be irradiated toward the scanning range. (See light L32).
走査角度範囲内に存在する物体Ｂで反射し、入射方向とは逆方向に戻ってくるレーザ光（反射光）のうち、格子方向と同じ偏光方向を有する成分（ＴＭ成分）は、偏光分離素子３４を透過して１／４波長板２５に到達する（光Ｌ３４を参照）。１／４波長板３５を通過した反射光は、直線偏光から円偏光に変換されて再帰性反射素子３６に到達する（光Ｌ３５を参照）。 Of the laser light (reflected light) reflected by the object B existing within the scanning angle range and returning in the direction opposite to the incident direction, the component having the same polarization direction as the grating direction (TM component) is a polarization separation element. 34 and reaches the quarter-wave plate 25 (see the light L34). The reflected light that has passed through the quarter-wave plate 35 is converted from linearly polarized light to circularly polarized light and reaches the retroreflective element 36 (see the light L35).
再帰性反射素子３６に到達した反射光は、再帰性反射素子３６で入射方向とは逆方向に反射し、再び１／４波長板２５に到達する（光Ｌ３６を参照）。１／４波長板３５を通過した反射光（再帰反射光）は、円偏光から直線偏光に変換されて偏光分離素子３４に到達する（光Ｌ３７を参照）。 The reflected light that has reached the retroreflective element 36 is reflected by the retroreflective element 36 in the direction opposite to the incident direction, and reaches the quarter-wave plate 25 again (see the light L36). The reflected light (retroreflected light) that has passed through the quarter-wave plate 35 is converted from circularly polarized light into linearly polarized light and reaches the polarization separation element 34 (see light L37).
偏光分離素子３４に到達した反射光は、１／４波長板３５を２度通過したことにより、偏光分離素子３４を透過したＴＭ成分からなる反射光とは、偏光方向が９０°異なったもの（即ちＴＥ成分）となっているため、偏光分離素子３４で反射して受光光学系３３に導かれる。この受光光学系３３に導かれた反射光は、受光光学系３３で収束して受光部３２に到達し、受光部３２にて受光信号に光電変換される（光Ｌ３８を参照）。 The reflected light that has reached the polarization separation element 34 has a polarization direction different from that of the TM component that has passed through the polarization separation element 34 by 90 ° because it has passed through the quarter wavelength plate 35 twice ( In other words, the TE component is reflected by the polarization separation element 34 and guided to the light receiving optical system 33. The reflected light guided to the light receiving optical system 33 is converged by the light receiving optical system 33 and reaches the light receiving unit 32, and is photoelectrically converted into a light receiving signal by the light receiving unit 32 (see the light L38).
そして、レーダ装置３では、この受光信号に基づき、図示しない信号処理部にて、発光部３０がパルスレーザ光を照射した時刻と、受光部３２が反射光を受光した時刻との差を計測し、その計測結果から、レーザ光を反射した物体までの距離が、走査範囲内の方位毎に求められることになる。 In the radar device 3, based on the light reception signal, a signal processing unit (not shown) measures the difference between the time when the light emitting unit 30 emits the pulsed laser light and the time when the light receiving unit 32 receives the reflected light. From the measurement result, the distance to the object reflecting the laser beam is obtained for each azimuth in the scanning range.
なお、反射光のうち、物体Ｂにて鏡面反射した成分については、偏光の向きが保存されるため、その殆どが偏光分離素子３４を透過して受光部２２に導かれるが、物体Ｂにて散乱反射した成分については、約半分が偏光分離素子３４を透過して受光部２２に導かれることになる。 Of the reflected light, the component that is specularly reflected by the object B is preserved in the direction of polarization, and most of the component is transmitted through the polarization separation element 34 and guided to the light receiving unit 22. About half of the components reflected and reflected are transmitted through the polarization beam splitter 34 and guided to the light receiving unit 22.
また、図４中において、点線で示した部分（但し物体Ｂを除く）は、偏光分離素子３４の角度を異なる角度に変化させることで照射光，反射光の経路が変化する様子を示したものである。 Further, in FIG. 4, a portion indicated by a dotted line (excluding the object B) shows a state in which the paths of the irradiation light and the reflected light are changed by changing the angle of the polarization separation element 34 to a different angle. It is.
＜効果＞
このように構成されたレーダ装置３によれば、受光部３２が受光部シールド３８及び偏光分離素子３４が形成する電磁遮蔽空間内に配置されているため、レーザ光の照射時に発光部３０にて発生した電磁ノイズが、反射光を取り込むために設けられた受光部シールド３８の開口部から（即ち偏光分離素子３４を介して）侵入することを抑制することができる。
<Effect>
According to the radar device 3 configured as described above, the light receiving unit 32 is disposed in the electromagnetic shielding space formed by the light receiving unit shield 38 and the polarization separation element 34, so that the light emitting unit 30 performs the irradiation with the laser light. The generated electromagnetic noise can be prevented from entering from the opening of the light receiving portion shield 38 provided for taking in the reflected light (that is, via the polarization separation element 34).
つまり、発光部３０にて発生し、受光部３２に干渉する電磁ノイズの影響を低減することができるため、発光部３０と受光部３２とを接近配置させて装置を小型化しても、電磁ノイズの影響の少ない受光信号を得ること、ひいては、正常な測距を行うことができる。 That is, since the influence of electromagnetic noise generated in the light emitting unit 30 and interfering with the light receiving unit 32 can be reduced, even if the light emitting unit 30 and the light receiving unit 32 are arranged close to each other and the apparatus is downsized, the electromagnetic noise is reduced. It is possible to obtain a received light signal that is less influenced by the above-mentioned, and thus to perform normal distance measurement.
なお、本実施形態において、偏光分離素子３４を回動させるための構成が第２走査手段に相当する。
［他の実施形態］
以上、本発明のいくつかの実施形態について説明したが、本発明は上記実施形態に限定されるものではなく、本発明の技術的範囲に属する限り種々の形態を取ることができる。
In the present embodiment, the configuration for rotating the polarization separation element 34 corresponds to the second scanning unit.
[Other Embodiments]
As mentioned above, although several embodiment of this invention was described, this invention is not limited to the said embodiment, As long as it belongs to the technical scope of this invention, it can take a various form.
例えば、上記実施形態では、レーザ光によって走査角度範囲内を走査するように構成したが、第１及び第２実施形態における走査部１６，２６を省略したり、第３実施形態における偏光分離素子３４を固定して取り付けたりすることで、走査をしないように構成してもよい。 For example, in the above embodiment, the scanning angle range is scanned by the laser beam. However, the scanning units 16 and 26 in the first and second embodiments are omitted, or the polarization separation element 34 in the third embodiment. It may be configured so that scanning is not performed by fixing and fixing the.
１，２，３…レーダ装置 １０，２０，３０…発光部 １１，２１，３１…投光光学系 １２，２２，３２…受光部 １３，２３，３３…受光光学系 １４，２４，３４…光路変更部（偏光分離素子） ５，２５，３５…１／４波長板 １６，２６…走査部 １７，２７，３７…発光部シールド １８，２８，３８…受光部シールド ３６…再帰性反射素子 DESCRIPTION OF SYMBOLS 1, 2, 3 ... Radar apparatus 10, 20, 30 ... Light emission part 11, 21, 31 ... Light projection optical system 12, 22, 32 ... Light reception part 13, 23, 33 ... Light reception optical system 14, 24, 34 ... Optical path Change unit (polarized light separating element) 5, 25, 35... 1/4 wavelength plate 16, 26... Scanning unit 17, 27, 37 ... Light emitting unit shield 18, 28, 38 ... Light receiving unit shield 36.
Claims (7)
光を受光する受光部と、
予め設定された第１偏光方向の成分の光を透過し、前記第１偏光方向と直交する第２偏光方向の成分の光を反射することにより、前記発光部から照射された照射光を、予め設定された投射方向に導くと共に、前記投射方向から到来する反射光を前記受光部に導く光路変更部と、
を備え、
前記光路変更部は、前記照射光の波長より短い間隔で周期的に配置された金属細線からなる構造体を有した偏光分離素子からなり、
前記発光部及び前記受光部のうち一方が、光を通過させる開口部を有する電磁遮蔽体と、該開口部を塞ぎ且つ前記構造体が前記電磁遮蔽体と互いに導通するように設けた前記偏光分離素子とで形成された電磁遮蔽空間内に配置されていることを特徴とするレーダ装置。 A light emitting unit that emits light;
A light receiving portion for receiving light;
By transmitting the light of the first polarization direction component set in advance and reflecting the light of the second polarization direction component orthogonal to the first polarization direction, the irradiation light irradiated from the light emitting unit is An optical path changing unit that guides reflected light coming from the projection direction to the light receiving unit while guiding the set projection direction,
With
The optical path changing unit is a polarization separation element having a structure made of fine metal wires periodically arranged at intervals shorter than the wavelength of the irradiation light,
One of said light emitting portion and the light receiving portion, an electromagnetic shielding member having an opening for passing light, the polarization of opening the busy technique and the structure is arranged so as to electrically connected to each other with the electromagnetic shield A radar apparatus, wherein the radar apparatus is disposed in an electromagnetic shielding space formed by a separation element.
前記発光部，前記受光部，前記偏光分離素子は、前記偏光分離素子を透過した前記照射光の進行方向が前記投射方向となり、前記偏光分離素子で反射した前記反射光を、前記受光部が受光する位置関係を有することを特徴とする請求項１に記載のレーダ装置。 The light emitting unit is disposed in the electromagnetic shielding space,
In the light emitting unit, the light receiving unit, and the polarization separation element, the traveling direction of the irradiation light transmitted through the polarization separation element is the projection direction, and the light reception unit receives the reflected light reflected by the polarization separation element. The radar apparatus according to claim 1, wherein the radar apparatus has a positional relationship.
前記発光部，前記受光部，前記偏光分離素子は、前記偏光分離素子で反射した前記照射光の進行方向が前記投射方向となり、前記偏光分離素子を透過した前記反射光を、前記受光部が受光する位置関係を有することを特徴とする請求項１に記載のレーダ装置。 The light receiving unit is disposed in the electromagnetic shielding space,
In the light emitting unit, the light receiving unit, and the polarization separation element, the traveling direction of the irradiation light reflected by the polarization separation element is the projection direction, and the light reception unit receives the reflected light transmitted through the polarization separation element. The radar apparatus according to claim 1, wherein the radar apparatus has a positional relationship.
前記偏光分離素子と前記反射素子との間に設けられた１／４波長板と、
を備え、前記受光部は、前記反射素子にて反射され１／４波長板を通過して到来する反射光を再帰反射光として、前記偏光分離素子で反射した前記再帰反射光を受光する位置に設けられていることを特徴とする請求項３に記載のレーダ装置。 A reflection element that reflects the reflected light transmitted through the polarization separation element toward the incident direction of the reflected light; and
A quarter-wave plate provided between the polarization separation element and the reflection element;
The light receiving unit is configured to receive the retroreflected light reflected by the polarization separation element, with the reflected light reflected by the reflective element and passing through the quarter-wave plate as retroreflected light. The radar apparatus according to claim 3, wherein the radar apparatus is provided.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2011209360A JP5664512B2 (en) | 2011-09-26 | 2011-09-26 | Radar equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2011209360A JP5664512B2 (en) | 2011-09-26 | 2011-09-26 | Radar equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2013068584A JP2013068584A (en) | 2013-04-18 |
| JP5664512B2 true JP5664512B2 (en) | 2015-02-04 |
Family
ID=48474429
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2011209360A Active JP5664512B2 (en) | 2011-09-26 | 2011-09-26 | Radar equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5664512B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106226783B (en) * | 2016-09-14 | 2019-02-12 | 苏州光讯环境科技有限公司 | Atmospheric particulates optical parameter measurement system based on laser radar |
| KR102162047B1 (en) * | 2017-02-17 | 2020-10-06 | 호쿠요덴키 가부시키가이샤 | Object capture device |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ATE100214T1 (en) * | 1987-03-20 | 1994-01-15 | Digital Optronics Corp | IMAGE SYSTEM IN THREE DIMENSIONS WITH COHAERENT OPTICAL DETECTION. |
| JPH02226111A (en) * | 1989-02-28 | 1990-09-07 | Copal Electron Co Ltd | Optical deflecting device |
| JPH0375544A (en) * | 1989-08-18 | 1991-03-29 | Nippon Telegr & Teleph Corp <Ntt> | Apparatus for inspecting inside of laser tube |
| JPH05312646A (en) * | 1992-05-15 | 1993-11-22 | Mitsubishi Electric Corp | Wavelength measuring apparatus and laser unit mounted thereon |
| JPH0659038A (en) * | 1992-08-07 | 1994-03-04 | Nissan Motor Co Ltd | Laser radar for vehicle |
| JPH07333544A (en) * | 1994-06-07 | 1995-12-22 | Dainippon Screen Mfg Co Ltd | Optical deflector |
| JPH09196620A (en) * | 1996-01-12 | 1997-07-31 | Yaskawa Electric Corp | Reflection type optical displacement detector |
| JP3805316B2 (en) * | 2003-03-14 | 2006-08-02 | 富士通株式会社 | Optical scanning touch panel |
| JP2005114857A (en) * | 2003-10-03 | 2005-04-28 | Enplas Corp | Optical element and optical pickup device using the same |
| JP5278819B2 (en) * | 2009-05-11 | 2013-09-04 | 株式会社リコー | Stereo camera device and vehicle exterior monitoring device using the same |
| JP5494569B2 (en) * | 2011-05-24 | 2014-05-14 | 株式会社デンソー | Radar equipment |
-
2011
- 2011-09-26 JP JP2011209360A patent/JP5664512B2/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2013068584A (en) | 2013-04-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9285266B2 (en) | Object detector including a light source with light emitting region of a first size in a first direction and a second size in a second direction | |
| JP6111617B2 (en) | Laser radar equipment | |
| US20090185158A1 (en) | Device for optical distance measurement | |
| US20190041498A1 (en) | LIDAR Receiver Using a Waveguide and an Aperture | |
| JP2014052366A (en) | Optical measurement instrument and vehicle | |
| KR20170071394A (en) | Detecting device for lidar light source without rotation and scanning | |
| US11867808B2 (en) | Waveguide diffusers for LIDARs | |
| JP2017129573A (en) | Photoelectronic sensor and object detection method | |
| TWI664398B (en) | Optical rotary encoder | |
| US20200309514A1 (en) | Distance measuring module | |
| JP6460445B2 (en) | Laser range finder | |
| JP5664512B2 (en) | Radar equipment | |
| US7826039B2 (en) | Target acquisition device | |
| KR20090108310A (en) | Bi-directional optical module using optical fiber and laser range finder using the same | |
| EP3364229B1 (en) | Optical-scanning-type object detection device | |
| US11333880B2 (en) | Coaxial macro scanner system | |
| JP7462747B2 (en) | Multilayer Optical Devices and Systems | |
| JPWO2018147454A1 (en) | Scanning optical system and laser radar device | |
| JP6388383B2 (en) | Laser range finder | |
| CN115480254A (en) | Detection method and device | |
| JP6015367B2 (en) | Radar equipment | |
| KR100976299B1 (en) | Bi-directional optical module and laser range finder using the same | |
| JP7475145B2 (en) | Electromagnetic wave detector and scanner | |
| US10823955B2 (en) | Grating-based spatial mode filter for laser scanning | |
| WO2020066718A1 (en) | Electromagnetic wave detection device and information acquisition system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20131122 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20140408 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20140409 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20140528 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20141111 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20141124 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 5664512 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |