JPS5814602B2 - KeijiyousokuteiSouchiyoukougakukei - Google Patents

Description

【発明の詳細な説明】 本発明は目標物体迄の距離を測定しその連続により目標
物体の形状を測定する装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for measuring the distance to a target object and measuring the shape of the target object by continuously measuring the distance to the target object.

従来より、第１図に示される如き目標物体の形状を測定
する装置の原理的なものは知られている。Conventionally, the principle of an apparatus for measuring the shape of a target object as shown in FIG. 1 has been known.

この装置においては、光源１より射出される光線束は送
光用レンズ２で収斂して目標物体３上に照射され、その
照射像を送光用レンズ２の光軸とある一定角θをなす光
軸を有する受光用レンズ４で反射鏡５を介して検出器６
上に再度結像する。In this device, a beam of light emitted from a light source 1 is converged by a light transmitting lens 2 and irradiated onto a target object 3, and the irradiated image is formed at a certain angle θ with the optical axis of the light transmitting lens 2. A light receiving lens 4 having an optical axis passes through a reflecting mirror 5 to a detector 6.
refocus on the top.

次に物体が変位し被測定点３′の位置に移動した時、物
体３′上に前記と同様に照射像を結像させる為に送光レ
ンズ２を移動させ更に前記と同じ角θで物体３′からの
反射光を受光する為に受光用レンズ４と反射鏡５を動か
して検出器に結像させ反射鏡５の移動量を測定し三角測
量の原理により物体３から３′までの変位を測定する。Next, when the object is displaced and moves to the position of the measured point 3', the light transmitting lens 2 is moved to form an irradiation image on the object 3' in the same manner as above, and the object is further moved at the same angle θ as above. In order to receive the reflected light from object 3', the light receiving lens 4 and reflecting mirror 5 are moved to form an image on the detector, and the amount of movement of the reflecting mirror 5 is measured, and the displacement from object 3 to 3' is determined by the principle of triangulation. Measure.

この様な手法は送光用レンズ２と受光用レンズ４及び反
射鏡５に各々独立にそれに応じた移動量を与えてやらね
ばならぬ為装置自体の機構が大型化しそれに伴う複雑化
は避けられない。In such a method, the light transmitting lens 2, the light receiving lens 4, and the reflecting mirror 5 must each be given a corresponding movement amount independently, so that it is possible to avoid increasing the size of the mechanism of the device itself and the accompanying complexity. do not have.

又これらを簡素化する為送光用レンズ２を装置に固定し
光源にレーザーを使用して送光用レンズ２を介し物体３
，３′をできるだけ小さなスポットで照射する様にさせ
たとしても物体距離によるスポット径の変化によりその
照射像を受光用レンズ群４を通して検出器に結像した時
一定の大きさが得られない為、一定の精度を得ることが
難しいばかりではなく、スポット径の大きくなる位置で
は物体形状の細かい変化を感知する事が困難となる等の
欠点がある。In addition, in order to simplify these steps, the light transmitting lens 2 is fixed to the device, and a laser is used as a light source to transmit the light to the object 3 through the light transmitting lens 2.
, 3' is made to irradiate as small a spot as possible, because the spot diameter changes depending on the object distance, a constant size cannot be obtained when the irradiated image is formed on the detector through the light receiving lens group 4. However, it is not only difficult to obtain a certain level of accuracy, but also has drawbacks such as difficulty in sensing minute changes in the shape of the object at positions where the spot diameter becomes large.

本発明は物体の移動距離に無関係に測定時にはほぼ一定
の大きさの照射像を物体に与え、かつ検出器にほぼ一定
の大きさの照射面の像を得る為にアフオーカルなレンズ
群を有する送光レンズ系と受光レンズ系を同時に１つの
ステージ上で光源と検出器に対し相対的に移動させ、か
つその構成が非常に簡単である物体の形状測定装置用光
学系を提供する事を目的とする。The present invention provides a transmitter having an afocal lens group in order to give an irradiation image of a substantially constant size to the object during measurement regardless of the distance traveled by the object, and to obtain an image of the irradiation surface of a substantially constant size on the detector. The purpose of the present invention is to provide an optical system for an object shape measuring device that allows an optical lens system and a light receiving lens system to be moved simultaneously on one stage relative to a light source and a detector, and that has a very simple configuration. do.

以下本発明の原理を第２図により説明する。The principle of the present invention will be explained below with reference to FIG.

第２図は焦点距離がＦ１，Ｆ′１て焦点距離がｆ１なる
レンズ群７と焦点位置がＦ２，Ｆ′２で焦点距離がｆ２
なるレンズ群８の一方の焦点位置Ｆ′１，Ｆ２が互いに
一致する所謂アフオーカル系と成した光学系を示してい
る。Figure 2 shows a lens group 7 whose focal length is F1, F'1 and whose focal length is f1, and a lens group whose focal length is F2, F'2 and whose focal length is f2.
This shows an optical system that is a so-called afocal system in which the focal positions F'1 and F2 of one of the lens groups 8 coincide with each other.

焦点Ｆ１からＸの所に置かれた物点Ｏはアフオーカル系
により焦点Ｆ′２からＹだけ離れた所に結像する。An object point O placed at a distance X from the focal point F1 is imaged at a distance Y from the focal point F'2 by the afocal system.

その間には以下の関係がある。There is the following relationship between them.

従って物点の微少変位ΔＸを考えた時物点Ｏと共役な像
点Ｏ′の移動量ΔＹも同様に下記の様に示される。Therefore, when considering the minute displacement ΔX of the object point, the amount of movement ΔY of the image point O' conjugate to the object point O is also expressed as follows.

従ってΔＹはΔＸと同じ方向に変位する事がわかる。Therefore, it can be seen that ΔY is displaced in the same direction as ΔX.

これを逆に考えれば像点Ｏ′を移動させずにレンズ群７
，８全体をａだけ移動させれば物点０の位置が （→上
） −１ ａだけ元の位置から移動する事になる。Considering this in reverse, lens group 7 can be moved without moving the image point O'.
, 8 by a distance, the position of object point 0 will move by (→top) −1 a from its original position.

この様にアフオーカル系を使用すれば物点Ｏの移動量と
アフオーカル系の動き量ａは正比例する為アフオーカル
系の動き量が判れば容易に物点の変位量を知る事ができ
ると共に結像倍率ｍも下記に示される如く物点の変位に
伴うアフオーカル系の移動量に関係なく常に一定である
という利点がある。In this way, if the afocal system is used, the amount of movement of the object point O and the amount of movement a of the afocal system are directly proportional, so if the amount of movement of the afocal system is known, the amount of displacement of the object point can be easily determined, and the imaging magnification As shown below, m also has the advantage of always being constant regardless of the amount of movement of the afocal system accompanying the displacement of the object point.

又レン群７，８の各々の焦点距離の比で倍率及び物体の
移物量に対するアフオーカル系レンズ群の動き量が任意
に決定される事も大きな利点の１つてある。Another great advantage is that the amount of movement of the afocal lens group relative to the magnification and the amount of object displacement can be arbitrarily determined by the ratio of the focal lengths of the lens groups 7 and 8.

以下本発明の光学系を第３図に示す第１の実施例により
説明する。The optical system of the present invention will be explained below using a first embodiment shown in FIG.

送光用レンズ系は光源１から射出する光線束を結像させ
る為の補助的なレンズ群７とアフオーカルに成した焦点
距離ｆ１なる送光第１レンズ群２ａと焦点距離ｆ２なる
送光第２レンズ群２ｂで物体３上に小さな光源像を結像
照射する様に成されている。The light transmitting lens system includes an auxiliary lens group 7 for forming an image of the beam of light emitted from the light source 1, a first light transmitting lens group 2a having a focal length f1, and a second light transmitting lens group 2a having a focal length f2, which are arranged afocally. A small light source image is formed and irradiated onto the object 3 by the lens group 2b.

受光用レンズ系は物体照射軸とほぼ一定の角θを中心と
して散乱された光線束を集光し検出器６上に照射面の像
を結像させる。The light-receiving lens system condenses the scattered light beams around an approximately constant angle θ with respect to the object irradiation axis, and forms an image of the irradiated surface on the detector 6.

受光用レンズ系はその光軸が送光用レンズ系の光軸と平
行になる様に反射鏡５を設け、その平行な光軸と光軸が
一致する様に設けられたアフオーカル系となした焦点距
離ｆ３なる受光用第１レンズ群４ａと焦点距離ｆ４なる
第２レンズ群４ｂと結像に補助的働きをするレンズ群８
より成っている。The light-receiving lens system is an afocal system in which a reflecting mirror 5 is provided so that its optical axis is parallel to the optical axis of the light-transmitting lens system, and the optical axis is aligned with the parallel optical axis. A first lens group 4a for light reception with a focal length of f3, a second lens group 4b with a focal length of f4, and a lens group 8 that performs an auxiliary function for image formation.
It consists of

更に光源１と検出器６と反射鏡５は同一ステージに設け
られ一体化されて動く様に構成されている。Furthermore, the light source 1, the detector 6, and the reflecting mirror 5 are provided on the same stage and are configured to move integrally.

今物体の被検点が３の位置から３′の位置にΔＸだけ変
位したとする時、前述した様に光源１をΔＹだけΔＸと
同一の方向に移動させ、光源１の光を物体３上に結像す
る為には なる関係を満す様に送光用第１、第２レンズ群の焦点距
離を定めれば良い。Now, suppose that the test point of the object has been displaced from position 3 to position 3' by ΔX. As mentioned above, move light source 1 by ΔY in the same direction as ΔX, and direct the light of light source 1 onto object 3. In order to form an image, the focal lengths of the first and second lens groups for light transmission may be determined so as to satisfy the following relationship.

この時反射鏡５と検出器６を光源と同量のΔＹだけ移動
させる為には受光軸方向の物体の移動量をΔＸとする七 なる関係を満す様に各々のレンズ群の焦点距離を決定す
れば良い。At this time, in order to move the reflecting mirror 5 and detector 6 by the same amount ΔY as the light source, the focal length of each lens group must be adjusted so as to satisfy the seven relationships where ΔX is the amount of movement of the object in the direction of the light receiving axis. All you have to do is decide.

従ってこの様に各レンズ群の焦点距離を定めれば物体に
光源の鐵が結像する時にはいつもその像は検出器上にも
結１象される事となる。Therefore, if the focal length of each lens group is determined in this manner, whenever the light source's iron is imaged on an object, that image will also be formed on the detector.

ここで更に形状を測定する方法について記す。Here, we will further describe the method for measuring the shape.

測定物（被検物体）３に光源１の像が結像する様になす
。The image of the light source 1 is formed on the measurement object (test object) 3.

その測定物からの反射光をある一定の角度で反射鏡５と
受光用レンズ４ｂ ，４ａ ，８で検出器６に設けられ
たリニア・アレイ状に並んだ受光素子群の中点近傍に結
像する様にする。The reflected light from the object to be measured is focused at a certain angle by the reflecting mirror 5 and the light-receiving lenses 4b, 4a, and 8 into an image near the center of the light-receiving elements arranged in a linear array on the detector 6. do as you like.

この受光素子の中点を基準とし、測定物体が測定装置に
対し相対的に移動し、Ｍｉｌｌ定点が変わると共に測定
装置から被測定点までの距離が変わると、それに伴って
受光素子に結像する像の位置が変わる。When the object to be measured moves relative to the measuring device using the center point of this light-receiving element as a reference, and the Mill fixed point changes and the distance from the measuring device to the point to be measured changes, an image is formed on the light-receiving element accordingly. The position of the statue changes.

この時測定物からの反射光をあるー・定の角度で受ける
様に反射鏡５、光源１及び検出器６を動かす事により再
度物体上の照射点が初めに設定した受光素子群の中点近
傍にくる様にするその移動量ΔＹは前述の如くΔＸに正
比例するから照射位置の移動量を知る事ができそれを連
続的に行う事により基準よりの凹凸つまり断面の形状を
知る事ができる。At this time, by moving the reflector 5, light source 1, and detector 6 so that the reflected light from the object to be measured is received at a certain angle, the irradiation point on the object is again set at the midpoint of the initially set light receiving element group. The amount of movement ΔY to bring it closer is directly proportional to ΔX as mentioned above, so you can know the amount of movement of the irradiation position, and by doing this continuously, you can know the unevenness from the reference, that is, the shape of the cross section. .

更に測定物体を前記移動方向と異なる方向に、例えば直
角方向に順次適当な移動をさせ、前記操作を繰返すこと
により三次元的に物体形状を知ることができる。Further, by sequentially appropriately moving the object to be measured in a direction different from the movement direction, for example, at right angles, and repeating the above operation, the shape of the object can be determined three-dimensionally.

尚、同様に第４図に示す様に光源１と検出器６を固定し
、送光用レンズのアフオーカルレンズ群２ａ，２ｂと受
光用レンズのアフオーカルレンズ群４ａ，４ｂを一体化
して物点の変位（３から３′）に伴いその変位方向とは
逆方向に移動させ、一体化したアフオーカルなレンズ群
２ ａ ２ ｂ ，４ａ４ｂの移動量と同量そのアフオ
ーカルなレンズ群の移動方向とは逆方向に反射鏡５を移
動さぜても前述した論理は変る事なく同様の結果が得ら
れる。Similarly, as shown in FIG. 4, the light source 1 and the detector 6 are fixed, and the afocal lens groups 2a and 2b of the light transmitting lens and the afocal lens groups 4a and 4b of the light receiving lens are integrated. As the object point is displaced (from 3 to 3'), the afocal lens group is moved in the opposite direction to the displacement direction, and the afocal lens group is moved by the same amount as the movement of the integrated afocal lens groups 2 a 2 b and 4 a 4 b. Even if the reflecting mirror 5 is moved in the opposite direction, the above-mentioned logic remains unchanged and the same result can be obtained.

次に第２の実施例を第５図により示す。Next, a second embodiment is shown in FIG.

第３図第４図に示した第１実施例は光源１と検出器６と
反射鏡５を一体化して動かすものであり又アフオー力ル
なレンズ群２ ａ ＋ ２ ｂ ，４ ａ ＋４ｂを一
体化して反射鏡５と同量だけ互いに逆方向に動かすもの
であるが、光源１と検出器６は装置的にも大がかりであ
り、又電気的結線をされている為どちらかというと動か
したくない部材であり又レンズ群と反射鏡５を互いに逆
方向に動かす手段を設ける事も精度への悪影響を与える
故、反射鏡５とアフオー力ルなレンズ群２ ａ ＋ ２
ｂ ＋４ａ，４ｂを一体化して移動し、光源１と検出
手段を固定するという方法が望まれる。In the first embodiment shown in FIGS. 3 and 4, the light source 1, detector 6, and reflector 5 are integrated and moved, and the affor lens groups 2a + 2b, 4a + 4b are integrated. However, since the light source 1 and the detector 6 are large-scale devices and are electrically connected, I would rather not move them. Providing a means for moving the lens group and the reflecting mirror 5 in opposite directions has a negative effect on accuracy, so the reflecting mirror 5 and the lens group 2 a + 2 which are in an asymmetrical manner have an adverse effect on accuracy.
A method is desired in which the light source 1 and the detection means are fixed by moving the b+4a and 4b as one unit.

それには送光用レンズ系と被検物体の間にその光軸とψ
の傾き角度を有する様に設けられた固定反射鏡５ａを設
ける事によりアフオーカルなレンズ群２ａ ， ２ｂ４
ａ，４ｂと前述の可動なる反射鏡５と一体化でき同一方
向に動かし得る事ができる。For this purpose, the optical axis and ψ should be
By providing a fixed reflecting mirror 5a that has an inclination angle of
a, 4b and the above-mentioned movable reflecting mirror 5, so that they can be moved in the same direction.

下記に詳述すると、各部材の作用は第１実施例と同様で
あり第１レンズ群２ａと第２レンズ群２１）の焦点距離
との関係を とし、同様に（ ｆ ４／ ｆ ３ ）２＝ ｓｉｎψ
／ｓｉｎθ なる関係を有する様に各レンズ群の焦点距
離を定めれば良い。To explain in detail below, the function of each member is the same as in the first embodiment, and the relationship between the focal lengths of the first lens group 2a and the second lens group 21) is similarly expressed as (f 4 / f 3 )2. = sinψ
The focal length of each lens group may be determined so as to have the relationship: /sinθ.

又この固定反射鏡５ａは受光側に設けられ送光側に可動
な反射鏡５を設けても良い。Further, the fixed reflecting mirror 5a may be provided on the light receiving side, and the movable reflecting mirror 5 may be provided on the light transmitting side.

尚第６図に示したごとく第２の実施例は第４図の第１の
実施例の如くレンズ群を固定して光源１と検出千段６を
反射鏡５に対し逆方向に移動する様に成しても同様であ
る事は言うまでもない。As shown in FIG. 6, in the second embodiment, the lens group is fixed as in the first embodiment shown in FIG. Needless to say, the same is true even if it is made.

又物点が微少変位しかしない様な時の測定ならば可動反
射鏡５を固定して物点の移動に伴う結像位置のずれを送
光受光用レンズ系の移動により補正し、その際送光用レ
ンズ系との一定角が変化するので検出器６上で今までと
は異なった位置に結像する事となりその移動量を物点の
移動量に換算して読み取っても良い。In addition, for measurements when the object point is only slightly displaced, the movable reflector 5 is fixed, and the shift in the imaging position due to the movement of the object point is corrected by moving the light transmitting and receiving lens system. Since the constant angle with the optical lens system changes, the image is formed at a different position on the detector 6, and the amount of movement may be converted into the amount of movement of the object point and read.

尚図中では凸レンズ２群によりアフオカル系を構成して
いるが凸凹レンズのアフオーカル系で構成しても伺ら本
発明に悪い影響を及ぼさない。In the figure, an afocal system is constructed by two groups of convex lenses, but the present invention will not be adversely affected even if the afocal system is composed of concave and convex lenses.

又送光用レンズ光軸との一定角θは大きい程物点の移動
に際して受光用ミラーの移動量が大となる故微少変化に
対して精度良く測定できる事は言うまでもない。It goes without saying that the larger the constant angle θ with the optical axis of the light-transmitting lens, the greater the amount of movement of the light-receiving mirror when the object point moves, so that minute changes can be measured more accurately.

以上述べたことから、本発明は物体の断面形状、形状測
定装置用として使用可能なばかりでなく、距離測定装置
用としても使用可能であることは言うに及ばない。From the above description, it goes without saying that the present invention can be used not only as an apparatus for measuring the cross-sectional shape and shape of an object, but also as a distance measuring apparatus.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は従来の形状測定装置用光学系の原理的説明図、
第２図は本発明による光学系の原理説明図、第３図は本
発明による第１実施例の光学系を示す説明図、第４図は
該第１実施例の変形例を示す説明図、第５図は第２実施
例の光学系説明図、第６図は該第２実施例の変形例を示
す説明図である。 （主要部分の符号の説明） １・・・・・・光源、２ａ
・・・・・・送光第１レンズ群、２ｂ・・・・・・送光
第２レンズ群、３・・・・・・物体、４ａ・・・・・・
受光用第１レンズ群、４ｂ・・・・・・受光用第２レン
ズ群、５・・・・・・反射鏡、６・・・・・・検出器、
５ａ・・・・・・固定反射鏡。Figure 1 is a diagram explaining the principle of the optical system for a conventional shape measuring device.
FIG. 2 is an explanatory diagram of the principle of the optical system according to the present invention, FIG. 3 is an explanatory diagram showing the optical system of the first embodiment according to the present invention, and FIG. 4 is an explanatory diagram showing a modification of the first embodiment. FIG. 5 is an explanatory diagram of the optical system of the second embodiment, and FIG. 6 is an explanatory diagram showing a modification of the second embodiment. (Explanation of symbols of main parts) 1...Light source, 2a
......Light sending first lens group, 2b... Light sending second lens group, 3...Object, 4a...
1st lens group for light reception, 4b...2nd lens group for light reception, 5...Reflector, 6...Detector,
5a...Fixed reflector.

Claims (1)

【特許請求の範囲】[Claims] １ 光源と、該光源からの光線束を被検物体上に集光投
射させる為少なくともアフオーカルレンズ群を含む第１
レンズ系と、該第１レンズ系により該被検物体上の照射
された部分の像を形成する為少なくともアフオーカルレ
ンズ群を含み、該第１レンズ系と互いに平行な光軸を有
する第２レンズ系と、該第１レンズ系により投射される
光線束のうち該被検物体表面上で所定の角度で反射され
る光線束を前記第２レンズ系へ導くために該両レンズ系
の光軸上の少なくとも一方に設けられた反射部材と、前
記第２レンズ系による像位置を検出するための検出手段
とを設け、さらに前記第１レンズ系と第２レンズ系との
両アフオーカルレンズ群が前記光源及び前記検知手段に
対して一体的に相対移動可能であることを特徴とする測
定装置用光学系。1 a light source and a first lens including at least an afocal lens group for condensing and projecting the light beam from the light source onto the object to be examined;
a second lens system including at least an afocal lens group for forming an image of a portion of the object to be examined illuminated by the first lens system, and having an optical axis parallel to the first lens system; a lens system; and optical axes of both lens systems for guiding a bundle of rays reflected at a predetermined angle on the surface of the object to be inspected out of the bundle of rays projected by the first lens system to the second lens system. a reflecting member provided on at least one of the upper lenses, and a detection means for detecting an image position by the second lens system, and further includes both afocal lens groups of the first lens system and the second lens system. An optical system for a measuring device, wherein the optical system is movable integrally with respect to the light source and the detection means.