JP2544789B2 - Optical displacement measuring device - Google Patents
Optical displacement measuring deviceInfo
- Publication number
- JP2544789B2 JP2544789B2 JP63246183A JP24618388A JP2544789B2 JP 2544789 B2 JP2544789 B2 JP 2544789B2 JP 63246183 A JP63246183 A JP 63246183A JP 24618388 A JP24618388 A JP 24618388A JP 2544789 B2 JP2544789 B2 JP 2544789B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- receiving surface
- reflected
- photodetector
- orthogonal
- 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 - Lifetime
Links
Landscapes
- Length Measuring Devices By Optical Means (AREA)
- Measurement Of Optical Distance (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、被測定対象物の変位を光学的に測定する光
学式変位測定装置に関する。Description: TECHNICAL FIELD The present invention relates to an optical displacement measuring device that optically measures displacement of an object to be measured.
近年、レーザ光等を用いて被測定対象物の変位を高精
度に測定する光学式変位測定装置が開発され、様々な分
野で使用されている。この種の変位測定装置は測定方式
により種々のものがあり、例えば測定原理として三角測
量法を用いた光学式変位測定装置は第３図（ａ）に示す
構成を有する。また、第３図（ｂ）は第３図（ａ）のＢ
−Ｂ線図に沿った矢視図である。同図において、１は光
源としてのレーザダイオード（以下LDと略称する）で、
このLD1から出射したレーザ光（測定光）は投光レンズ
２を介して被測定対象物３に投光させるようになってい
る。また、５は被測定対象物３の表面で反射・散乱した
レーザ光の一部を結像レンズ４を介して受光する光検出
器で、この光検出器５で検出された反射光は電気信号に
変換され、図示しない演算部に入力されるようになって
いる。2. Description of the Related Art In recent years, optical displacement measuring devices for measuring displacement of an object to be measured with high accuracy using laser light or the like have been developed and used in various fields. There are various kinds of displacement measuring devices of this kind depending on the measuring method. For example, an optical displacement measuring device using a triangulation method as a measuring principle has a configuration shown in FIG. 3 (a). Further, FIG. 3 (b) is B of FIG. 3 (a).
It is an arrow view along the -B diagram. In the figure, 1 is a laser diode (hereinafter abbreviated as LD) as a light source,
The laser light (measurement light) emitted from the LD1 is projected onto the object 3 to be measured via the light projecting lens 2. Reference numeral 5 denotes a photodetector that receives a part of the laser light reflected / scattered on the surface of the measured object 3 through the imaging lens 4, and the reflected light detected by the photodetector 5 is an electric signal. And is input to an arithmetic unit (not shown).
このように構成される光学式変位測定装置は、結像レ
ンズ４を通して光検出器５の受光面６上に結像された反
射光の光点が破線で示す如く被測定対象物３の変位量に
応じて移動する。したがって、前記演算部で光検出器５
の両側から流れ出す電流i1，i2を電圧V1，V2に変換し、
（V1−V2）／（V1＋V2）を演算することにより被測定対
象物３の変位量ｘを求めることができる。In the optical displacement measuring device configured as described above, the displacement amount of the object 3 to be measured is indicated by the light point of the reflected light imaged on the light receiving surface 6 of the photodetector 5 through the imaging lens 4 as indicated by the broken line. Move according to. Therefore, the photodetector 5 is
Currents i 1 and i 2 flowing out from both sides of the voltage are converted into voltages V 1 and V 2 ,
The displacement amount x of the measured object 3 can be obtained by calculating (V 1 −V 2 ) / (V 1 + V 2 ).
ところで、このような従来の光学式変位測定装置で
は、たとえ被測定物体３が第３図（ａ）の点線で示すよ
うに入射光の光軸に沿って前後に移動したときに、結像
レンズ４を通過した反射光の光点が常に光検出器５の受
光面６上で結像（焦点を結ぶ）するようにしている。し
たがって、図示するように、受光面６を、反射光の光軸
C2に直交する直交面Ｈに対して、測定光と反射光とを含
む投受光面内で角度θ1だけ傾斜させている。しかしな
がら、このように光検出器５を反射光の光軸C2に垂直な
面Ｈに対して角度θ1だけ傾けると、第４図に示す如く
光検出器５に入射した反射光が受光面６で反射して２次
反射光となり、受光面６を保護する透明プラスチック又
はガラス等の保護面７で再反射する。そして、保護面７
で反射した２次反射光は再び受光面６で反射するが、こ
のときの光検出器５の光点の位置出力が２次反射光によ
って影響を受け、測定精度が低下するという問題があっ
た。By the way, in such a conventional optical displacement measuring apparatus, when the measured object 3 moves back and forth along the optical axis of the incident light as shown by the dotted line in FIG. The light spot of the reflected light that has passed through 4 is always imaged (focused) on the light receiving surface 6 of the photodetector 5. Therefore, as shown in FIG.
It is tilted by an angle θ 1 with respect to the orthogonal plane H orthogonal to C 2 in the light projecting / receiving plane including the measurement light and the reflected light. However, when the photodetector 5 is tilted by the angle θ 1 with respect to the plane H perpendicular to the optical axis C 2 of the reflected light as described above, the reflected light incident on the photodetector 5 as shown in FIG. It is reflected by 6 to become secondary reflected light, and is reflected again by the protective surface 7 such as transparent plastic or glass that protects the light receiving surface 6. And the protective surface 7
The secondary reflected light reflected by is reflected by the light receiving surface 6 again, but the position output of the light spot of the photodetector 5 at this time is affected by the secondary reflected light, and there is a problem that the measurement accuracy deteriorates. .
本発明はこのような問題点を解消するためになされた
もので、その目的とするところは、２次反射光による影
響を低減でき、被測定対象物の変位を高精度に測定可能
な光学式変位測定装置を提供しようとするものである。The present invention has been made to solve such a problem, and an object thereof is an optical system capable of reducing the influence of secondary reflected light and measuring the displacement of a measured object with high accuracy. An object of the present invention is to provide a displacement measuring device.
上記課題を解決するために本発明は、被測定対象物に
測定光を投光する光源と、被測定対象物からの反射光を
結像光学系を介して受光するとともに受光面の前面を透
明の保護面で覆った光検出器と、この光検出器の受光面
上に結像された反射光の光点位置から被測定物体の変位
量を算出する演算部とを有した光学式変位測定装置にお
いて、光検出器の受光面を、反射光の光軸に直交する直
交面に対して、測定光と反射光とを含む投受光面内で、
常に反射光の光点が受光面上で結像するように、第１の
角度だけ傾斜させ、かつ、光検出器の受光面を、反射光
の光軸に直交する直交面に対して、投受光面に直交する
面内で、受光面で反射された反射光の２次反射光が保護
面で再度反射されて受光面に再度入射しないように、第
２の角度だけ傾斜させている。In order to solve the above-mentioned problems, the present invention receives a light source that projects measurement light onto an object to be measured, receives reflected light from the object to be measured through an imaging optical system, and makes the front surface of the light receiving surface transparent. Optical displacement measurement having a photodetector covered with a protective surface of the photodetector and an arithmetic unit for calculating the amount of displacement of the object to be measured from the light spot position of the reflected light imaged on the light receiving surface of the photodetector. In the device, the light receiving surface of the photodetector, with respect to the orthogonal surface orthogonal to the optical axis of the reflected light, in the light emitting and receiving surface including the measurement light and the reflected light,
It is inclined by a first angle so that the light spot of the reflected light always forms an image on the light receiving surface, and the light receiving surface of the photodetector is projected onto an orthogonal surface orthogonal to the optical axis of the reflected light. In the plane orthogonal to the light receiving surface, the secondary reflection light of the reflected light reflected by the light receiving surface is inclined by a second angle so that the secondary reflected light is not reflected again by the protective surface and re-enters the light receiving surface.
［作用］ 本発明においては、光検出器の受光面を、反射光の光
軸に直交する直交面に対して測定光と反射光とを含む投
受光面内で第１の角度だけ傾斜させ、かつ、反射光の光
軸に直交する直交面に対して投受光面に直交する面内で
第２の角度だけ傾斜させている。[Operation] In the present invention, the light receiving surface of the photodetector is tilted by a first angle within a light projecting and receiving surface including the measurement light and the reflected light with respect to an orthogonal plane orthogonal to the optical axis of the reflected light, Moreover, it is tilted by a second angle in the plane orthogonal to the light emitting / receiving surface with respect to the orthogonal plane orthogonal to the optical axis of the reflected light.
その結果、常時、光検出器の受光面上に反射光の光点
を結像させた状態で、かつ受光面で反射された反射光の
２次反射光が保護面で再度反射されて受光面に再度入射
する方向とは異なる方向に反射する。したがって、２次
反射光による影響を低減できる。As a result, the secondary reflected light of the reflected light reflected by the light receiving surface is constantly reflected again on the light receiving surface while the light spot of the reflected light is always imaged on the light receiving surface of the photodetector. Is reflected in a direction different from the direction of re-incident light. Therefore, the influence of the secondary reflected light can be reduced.
以下、本発明の実施例を図面を参照して説明する。 Embodiments of the present invention will be described below with reference to the drawings.
第１図は本発明の一実施例を示す図で、同図（ａ）は
光学式変位測定装置の構成図で、同図（ｂ）は（ａ）の
Ｂ−Ｂ線に沿った矢視図である。同図において、11は光
源としてのLDで、このLD11から出射したレーザ光は投光
レンズ12を介して被測定対象物13に投光されるようにな
っている。また、15は被測定対象物13の表面で反射・散
乱したレーザ光の一部を結像レンズ14を介して受光する
光検出器で、この光検出器15で受光した反射光は電気信
号に変換され、図示しない演算部へ入力されるようにな
っている。上記演算部は結像レンズ14を通して光検出器
15の受光面16上に結像された反射光の光点位置から被測
定対象物13の変位量を算出するように構成されており、
具体的には光検出器15の両側から流れ出す電流i1，i2を
電圧V1，V2に変換し、（V1−V2）／（V1＋V2）を演算す
ることにより被測定対象物13の変位量ｘを求めている。FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 1A is a configuration diagram of an optical displacement measuring device, and FIG. 1B is a view taken along the line BB of FIG. It is a figure. In the figure, 11 is an LD as a light source, and the laser light emitted from this LD 11 is projected onto an object 13 to be measured via a projection lens 12. Further, 15 is a photodetector that receives a part of the laser light reflected and scattered on the surface of the measured object 13 through the imaging lens 14, and the reflected light received by this photodetector 15 is converted into an electric signal. The data is converted and input to a calculation unit (not shown). The calculation unit is a photodetector through the imaging lens 14.
It is configured to calculate the displacement amount of the measured object 13 from the light point position of the reflected light imaged on the light receiving surface 16 of 15.
Specifically, the currents i 1 and i 2 flowing out from both sides of the photodetector 15 are converted into voltages V 1 and V 2 , and (V 1 −V 2 ) / (V 1 + V 2 ) is calculated to be measured. The displacement amount x of the object 13 is calculated.
また、前記光検出器15は第１図（ａ）に示す如く受光
面16を反射光の光軸C2と垂直な垂直面Ｈに対して、測定
光と反射光とを含む投受光面Ｓ内で、常に反射光の光点
が受光面16上で結像するように、第１の角度θ1だけ傾
斜させている。さらに、第１図（ｂ）に示すように、光
検出器15の受光面16を、反射光の光軸C2に直交する直交
面Ｈに対して、投受光面Ｓに直交する面内で、受光面16
で反射された反射光の２次反射光が保護面17で再度反射
されて受光面16に再度入射しないように、第２の角度θ
2だけ傾斜させている。この第２の角度θ2の具体的な値
は、第２図に示すように、保護面17の厚みと受光面16の
幅との幾何学的組合せによって定まる。Further, as shown in FIG. 1 (a), the photodetector 15 has a light receiving surface 16 with respect to a vertical surface H which is perpendicular to the optical axis C 2 of the reflected light, and a light emitting / receiving surface S including the measurement light and the reflected light. Inside, it is inclined by the first angle θ 1 so that the light spot of the reflected light always forms an image on the light receiving surface 16. Further, as shown in FIG. 1 (b), the light receiving surface 16 of the photodetector 15 is in the plane orthogonal to the light emitting / receiving surface S with respect to the orthogonal surface H orthogonal to the optical axis C 2 of the reflected light. , Light-receiving surface 16
The second angle θ is set so that the secondary reflected light of the reflected light reflected by is not reflected again by the protective surface 17 and does not enter the light receiving surface 16 again.
It is tilted by 2 . The specific value of the second angle θ 2 is determined by the geometrical combination of the thickness of the protective surface 17 and the width of the light receiving surface 16, as shown in FIG.
このように光検出器15の受光面16を、測定光の光軸C1
と反射光の光軸C2を含む投受光面Ｓに対して所定角度傾
けることにより、第２図に示す如く光検出器15の受光面
16で反射した２次反射光が保護面17で受光面16から外れ
る方向に反射するため、２次反射光による影響を低減で
き、被測定対象物の変位を高精度に測定することができ
る。In this way, the light receiving surface 16 of the photodetector 15 is moved to the optical axis C 1 of the measurement light.
And a light receiving surface S including the optical axis C 2 of the reflected light, the light receiving surface of the photodetector 15 is inclined as shown in FIG.
Since the secondary reflected light reflected by 16 is reflected by the protective surface 17 in a direction away from the light receiving surface 16, the influence of the secondary reflected light can be reduced, and the displacement of the measured object can be measured with high accuracy.
なお、本発明は上記実施例に限定されるものではな
く、特許請求の範囲に記載された要旨を逸脱しない範囲
で種々の設計的変更及び変形が可能である。たとえば、
前記実施例では測定光としてレーザ光を用いたが、レー
ザ光以外の測定光を用いた光学式変位測定装置にも適用
可能である。The present invention is not limited to the above embodiments, and various design changes and modifications can be made without departing from the scope of the claims. For example,
Although the laser light is used as the measurement light in the above-mentioned embodiment, the invention can be applied to an optical displacement measuring device using measurement light other than the laser light.
以上説明したように本発明は、被測定対象物に測定光
を投光する光源と、前記被測定対象物からの反射光を結
像光学系を介して受光する光検出器と、この光検出器の
受光面上に結像された反射光の光点位置から前記被測定
対象物の変位量を算出する演算部とを具備した光学式変
位測定装置において、反射光の光軸に直交する直交面に
対して測定光と反射光とを含む投受光面Ｓ内で第１の角
度だけ傾斜させている。さらに、同じく光検出器の受光
面を、同じく反射光の光軸に直交する直交面に対して、
投受光面に直交する面内で第２の角度だけ傾斜させてい
る。したがって、常に反射光の光点が受光面16上で結像
するので、光点位置の測定精度が向上すると共に、２次
反射光が再度受光面16に入射しないので、測定結果に２
次反射光の影響が混入するのを低減でき、被測定対象物
の変位を高精度に測定可能な光学式変位測定装置を提供
できる。As described above, the present invention provides a light source that projects measurement light onto an object to be measured, a photodetector that receives reflected light from the object to be measured via an imaging optical system, and this light detection. In an optical displacement measuring device comprising an arithmetic unit for calculating the displacement amount of the object to be measured from the light spot position of the reflected light imaged on the light receiving surface of the container, the orthogonality orthogonal to the optical axis of the reflected light The surface is tilted by a first angle within the light emitting / receiving surface S including the measurement light and the reflected light. Further, similarly, the light receiving surface of the photodetector with respect to the orthogonal plane orthogonal to the optical axis of the reflected light,
It is tilted by a second angle in a plane orthogonal to the light emitting / receiving surface. Therefore, since the light spot of the reflected light is always imaged on the light receiving surface 16, the measurement accuracy of the light spot position is improved, and the secondary reflected light does not enter the light receiving surface 16 again.
It is possible to reduce mixing of the influence of the secondary reflected light and provide an optical displacement measuring device capable of measuring the displacement of the object to be measured with high accuracy.
第１図は本発明の一実施例を示す図で、同図（ａ）は構
成図、同図（ｂ）は（ａ）のＢ−Ｂ線に沿った矢視図、
第２図は同実施例の作用を示す説明図、第３図は従来の
光学式変位測定装置を示す図で、同図（ａ）は構成図、
同図（ｂ）は（ａ）のＢ−Ｂ線に沿った矢視図、第４図
は発明が解決しようとする課題を説明するための図であ
る。 11……LD（レーザダイオード）、12……投光レンズ、13
……被測定対象物、14……結像レンズ、15……光検出
器、16……受光面、17……保護面、C1……測定光光軸、
C2……反射光光軸、Ｓ……投受光面。FIG. 1 is a diagram showing an embodiment of the present invention, in which FIG. 1 (a) is a configuration diagram, FIG. 1 (b) is a view taken along the line BB of FIG.
FIG. 2 is an explanatory view showing the operation of the embodiment, FIG. 3 is a view showing a conventional optical displacement measuring device, and FIG.
FIG. 4B is a view taken along the line BB in FIG. 4A, and FIG. 4 is a view for explaining a problem to be solved by the invention. 11 …… LD (laser diode), 12 …… Projector lens, 13
…… Object to be measured, 14 …… Imaging lens, 15 …… Photodetector, 16 …… Light receiving surface, 17 …… Protective surface, C 1 …… Measuring optical axis,
C 2 …… Reflected light optical axis, S …… Emitter / receiver surface.
Claims (1)
源（11）と、 前記被測定対象物（13）からの反射光を結像光学系（1
4）を介して受光するとともに受光面（16）の前面を透
明の保護面（17）で覆った光検出器（15）と、 この光検出器（15）の受光面（16）上に結像された反射
光の光点位置から前記被測定物体（13）の変位量を算出
する演算部と を有した光学式変位測定装置において、 前記光検出器（15）の受光面（16）を、前記反射光の光
軸（C2）に直交する直交面（Ｈ）に対して、前記測定光
と反射光とを含む投受光面（Ｓ）内で、常に前記反射光
の光点が前記受光面（16）上で結像するように、第１の
角度（θ1）だけ傾斜させ、 かつ、前記光検出器の受光面（16）を、前記反射光の光
軸（C2）に直交する直交面（Ｈ）に対して、前記投受光
面（Ｓ）に直交する面内で、前記受光面（16）で反射さ
れた前記反射光の２次反射光が前記保護面（17）で再度
反射されて前記受光面（16）に再度入射しないように、
第２の角度（θ2）だけ傾斜させることを特徴とする光
学式変位測定装置。1. A light source (11) for projecting measurement light onto an object to be measured (13), and an image forming optical system (1) for reflecting light from the object to be measured (13).
It is connected to the photodetector (15) that receives light via 4) and has the front surface of the light-receiving surface (16) covered with a transparent protective surface (17) and the light-receiving surface (16) of this photodetector (15). An optical displacement measuring device having a calculation unit for calculating the displacement amount of the object to be measured (13) from the imaged light spot position of the reflected light, wherein the light receiving surface (16) of the photodetector (15) is , With respect to the orthogonal plane (H) orthogonal to the optical axis (C 2 ) of the reflected light, the light point of the reflected light is always the above in the light projecting and receiving surface (S) including the measurement light and the reflected light. It is tilted by a first angle (θ 1 ) so that an image is formed on the light receiving surface (16), and the light receiving surface (16) of the photodetector is aligned with the optical axis (C 2 ) of the reflected light. The secondary reflected light of the reflected light reflected by the light receiving surface (16) in the surface orthogonal to the light emitting and receiving surface (S) with respect to the orthogonal surface (H) orthogonal to the orthogonal surface (H) is the protection surface (17). Reflected again at It said to not again entered the light-receiving surface (16) Te,
An optical displacement measuring device characterized by being tilted by a second angle (θ 2 ).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63246183A JP2544789B2 (en) | 1988-09-30 | 1988-09-30 | Optical displacement measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63246183A JP2544789B2 (en) | 1988-09-30 | 1988-09-30 | Optical displacement measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0293316A JPH0293316A (en) | 1990-04-04 |
| JP2544789B2 true JP2544789B2 (en) | 1996-10-16 |
Family
ID=17144748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63246183A Expired - Lifetime JP2544789B2 (en) | 1988-09-30 | 1988-09-30 | Optical displacement measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2544789B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5114120B2 (en) * | 2007-07-11 | 2013-01-09 | 株式会社ミマキエンジニアリング | Method for adjusting printing apparatus and method for adjusting optical axis |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61218909A (en) * | 1985-03-25 | 1986-09-29 | Matsushita Electric Works Ltd | Photoelectric object detecting device |
-
1988
- 1988-09-30 JP JP63246183A patent/JP2544789B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0293316A (en) | 1990-04-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4647193A (en) | Optical target ranging apparatus | |
| EP0366112B1 (en) | Optical coordinate input apparatus and position indicator therefor | |
| JPS60127403A (en) | Thickness measuring apparatus | |
| JPH08159714A (en) | Position detection sensor | |
| JP2544789B2 (en) | Optical displacement measuring device | |
| JPH10197212A (en) | Optical displacement sensor, optical thickness sensor, displacement detecting method, and thickness detecting method | |
| CN108646047A (en) | Based on tachogenerator of the Doppler effect with correcting principle and calibration and measurement method | |
| JP4363174B2 (en) | Coordinate input device | |
| JPH0778429B2 (en) | Ranging device | |
| JPS55124002A (en) | Optical position detector | |
| JP4175715B2 (en) | Optical scanning touch panel | |
| JPH0534437A (en) | Laser distance measuring apparatus | |
| JPS5946808A (en) | Method for measuring displacement of object by optical fiber | |
| JP4183327B2 (en) | Optical scanning touch panel | |
| JP2577234Y2 (en) | Laser rangefinder | |
| JP2573673B2 (en) | Optical displacement measuring device of triangulation method | |
| JPH09257470A (en) | Optical displacement sensor | |
| JPH0520989A (en) | Photoelectric sensor | |
| JP3329950B2 (en) | Optical displacement measuring device | |
| JPS59202012A (en) | Optical range finder | |
| JPH0410569B2 (en) | ||
| JP3501500B2 (en) | Distance measuring device and camera | |
| JPH0714810Y2 (en) | Rangefinder | |
| JPS5826325Y2 (en) | position detection device | |
| JPH03252519A (en) | Micron displacement gauge |