WO2018207310A1 - Procédé et composant de mesure de position - Google Patents

Procédé et composant de mesure de position Download PDF

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Publication number
WO2018207310A1
WO2018207310A1 PCT/JP2017/017867 JP2017017867W WO2018207310A1 WO 2018207310 A1 WO2018207310 A1 WO 2018207310A1 JP 2017017867 W JP2017017867 W JP 2017017867W WO 2018207310 A1 WO2018207310 A1 WO 2018207310A1
Authority
WO
WIPO (PCT)
Prior art keywords
groove
angle
image
base
column
Prior art date
Application number
PCT/JP2017/017867
Other languages
English (en)
Japanese (ja)
Inventor
孝弘 藤岡
宏則 堀切
賢元 池田
Original Assignee
ナルックス株式会社
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by ナルックス株式会社 filed Critical ナルックス株式会社
Priority to PCT/JP2017/017867 priority Critical patent/WO2018207310A1/fr
Priority to JP2017239493A priority patent/JP6989950B2/ja
Priority to US15/967,974 priority patent/US10295754B2/en
Priority to CN201810430660.1A priority patent/CN108896276B/zh
Priority to CN202111208827.8A priority patent/CN113933030A/zh
Priority to DE102018111233.5A priority patent/DE102018111233A1/de
Publication of WO2018207310A1 publication Critical patent/WO2018207310A1/fr
Priority to JP2021190918A priority patent/JP7244954B2/ja

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques

Definitions

  • the present invention relates to a position measuring method based on an image of a measuring apparatus provided with an imaging optical system using coaxial epi-illumination, and a component suitable for the above measuring method.
  • the lens and the optical fiber are aligned on the corresponding surface of the component.
  • the position reference portion which is the provided columnar convex portion is fitted into the concave portion provided in the connector.
  • a measuring device such as a CNC (Computer Numerical Control) image measuring machine (for example, Patent Document 1).
  • An object of the present invention is to provide a position measurement method for obtaining the position of a lens or the like with high accuracy using the position of a position reference portion of a component in an image of a measurement apparatus, and a component suitable for the measurement method described above. It is.
  • the position measurement method observes the position of a position reference portion on a plane and an arbitrary point in an image of a measurement apparatus including an imaging optical system using coaxial incident illumination, and the position This is a position measurement method for determining the position of the arbitrary point on the basis of the position of the reference portion.
  • the position reference portion has a columnar shape at least at the base, and includes a groove having a constant width around the base of the column, the bottom surface of the groove is parallel to the plane, and the outer periphery of the bottom surface of the groove Is provided with an inclined surface that rises from the bottom surface to the bottom surface at an angle ⁇ and reaches the flat surface.
  • the position measuring method of the present invention is a step of determining the position of the base periphery of the column from the position of the outer periphery of the bottom surface of the groove and the position of the reflection image of the outer periphery of the groove in the image of the measuring device. And determining the position of the position reference part from the position of the periphery of the base of the pillar, and determining the position of the arbitrary point with reference to the position of the position reference part.
  • the position of the peripheral edge at the base of the column is determined from the position of the outer peripheral edge of the bottom surface of the groove and the position of the reflected image of the outer peripheral edge. Since the position of the position reference part is determined from the position of the periphery of the base of the pillar, the position measurement error can be greatly reduced as compared with the case of determining the position of the position reference part from the position of the tip of the pillar. Can do.
  • ⁇ is the opening angle of the imaging optical system, ⁇ and the unit of the angle is ⁇ , Meet.
  • the light beam reflected by the inclined surface does not enter the measuring device. Therefore, it is preferable because the boundary between the bottom surface region and the inclined surface region becomes clear in the image obtained by the measuring apparatus.
  • ⁇ is the opening angle of the imaging optical system
  • ⁇ is the unit of angle
  • ⁇ is Meet.
  • NA is the numerical aperture of the microscope
  • W is the width of the groove
  • L is the length of the column.
  • the position of the arbitrary point is the position of the optical element.
  • the position of the optical element can be determined with high accuracy using the position of the position reference portion as a reference.
  • the component according to the second aspect of the present invention is a component including at least two position reference portions and an optical element on at least one plane.
  • the position reference portion has a columnar shape at least at the base, and includes a groove having a constant width around the base of the column, the bottom surface of the groove is parallel to the plane, and the outer periphery of the bottom surface of the groove Includes an inclined surface that rises from the bottom surface to the bottom surface at an angle ⁇ and reaches the flat surface, and the angle ranges from 20 degrees to 70 degrees.
  • the component according to this aspect is suitable for measuring the position of the optical element with high accuracy based on the position of the position reference unit based on the image of a measurement apparatus including an imaging optical system using coaxial incident illumination. .
  • FIG. 1 is a diagram illustrating a component 100 including a position reference unit 110 according to an embodiment of the present invention.
  • the two position reference parts 110 are substantially cylindrical.
  • the component 100 including the plurality of lenses 150 is connected to, for example, a connector including a plurality of optical fibers.
  • the two position reference parts 110 are used for connecting the component 100 and the connector.
  • the connector may include two concave portions corresponding to the two columnar position reference portions 110, and the position reference portions may be accommodated in the concave portions.
  • FIG. 2 is a view showing a cross section including the central axis of the position reference portion 110 ′ of the conventional component.
  • the measurement of the positions of the plurality of lenses 150 is performed using a measuring device such as a CNC (Computer Numerical Control) image measuring machine.
  • a measuring device such as a CNC (Computer Numerical Control) image measuring machine.
  • the position of the position reference unit 110 ′ is determined by observing the tip end portion of the column surrounded by a circle in FIG. 2 in an image acquired by a measuring apparatus such as an image measuring machine.
  • FIG. 3 is a view showing a cross section including the central axis of the position reference portion 110 of the component 100 according to the embodiment of the present invention.
  • the component 100 according to the embodiment of the present invention is different from the conventional component in that an annular groove 120 is provided around the base of the column 115 of the position reference unit 110.
  • 3 is a diagram showing a cross section of the groove 120 including the central axis of the position reference portion 110.
  • the width of the groove 120 is indicated by W, and the depth of the groove 120 is indicated by D.
  • the bottom surface 121 of the groove 120 is formed in parallel with the plane 101 of the component 100.
  • the roughness of the bottom surface 121 is preferably finished to 30 nm or less.
  • the outer periphery of the bottom surface 121 is provided with an inclined surface 123 that rises from the bottom surface 121 to the bottom surface 121 at a predetermined angle and reaches the surface 101.
  • the bottom surface 121 preferably defines the depth D of the groove 120 so as to form the same plane as the plane on which the lens 150 is disposed.
  • the corners indicated by A1 and A2 are preferably formed such that the cross section does not have a so-called R portion on the arc.
  • FIG. 4 is a diagram showing a measuring apparatus using coaxial epi-illumination used in the measuring method of the present invention.
  • the measuring device may be a CNC image measuring device.
  • the measurement apparatus includes a light source 301, a field lens 303, a half mirror 304, a condenser lens 305, an imaging lens 307, and an image acquisition unit 309.
  • the condenser lens 305, the half mirror 304, and the imaging lens 307 form an imaging optical system of the measuring device.
  • a surface of the component 100 including the position reference unit 110 is denoted by 101.
  • the light from the light source 301 forms an image of the light source at the pupil position of the condenser lens 305 via the field lens 303 and the half mirror 304.
  • Illumination of the surface 101 of the component 100 is performed via the condenser lens 305 using the image of the light source as a light source.
  • the light reflected by the surface 101 of the component 100 passes through the condenser lens 305, passes through the half mirror 304 and the imaging lens 307, and reaches the image acquisition unit 309.
  • FIG. 5 is a diagram showing a path of illumination light and reflected light for imaging of the coaxial epi-illumination of the measurement apparatus.
  • the above path is determined by the aperture angle of the imaging optical system of the measurement apparatus, that is, the aperture angle of the condenser lens 305.
  • chief rays are represented by L1 and L2, and an aperture angle is represented by ⁇ .
  • ⁇ is represented by a light beam whose angle with the normal of the plane 101 exceeds the opening angle ⁇ is not taken into the measuring device.
  • FIG. 6 is a diagram showing a path of light rays that travel perpendicularly to the bottom surface 121 of the groove 120 in the illumination light and an image of the light rays.
  • the reflected light of the light incident perpendicularly to the bottom surface 121 travels perpendicularly to the bottom surface 121 and therefore reaches the image acquisition unit 309.
  • the reflected light that is perpendicularly incident on the surface 101 also reaches the image acquisition unit 309.
  • the light beam traveling vertically to the bottom surface 121 is reflected by the inclined surface 123, it is further reflected by the side surface of the column 115 and does not reach the image acquisition unit 309.
  • the area of the bottom surface 121 and the plane 101 becomes bright, and the area of the inclined surface 123 becomes dark.
  • the boundary E between the region of the bottom surface 121 and the region of the inclined surface 123 is clearly shown.
  • FIG. 7 is a diagram showing a path of light rays that travel at an angle within a predetermined range with respect to the bottom surface 121 of the groove 120 in the illumination light, and an image of the light rays.
  • the reflected light of the light ray incident on the bottom surface 121 at an angle within the predetermined range is reflected by the bottom surface 121 and the side surfaces of the pillar 115 and then reaches the image acquisition unit 309.
  • the reflected light incident on the surface 101 also reaches the image acquisition unit 309.
  • the light ray traveling at an angle within the predetermined range with respect to the bottom surface 121 is reflected by the inclined surface 123, it is further reflected by the side surface of the column 115 and does not reach the image acquisition unit 309.
  • the reflected image obtained by the light beam reflected by the side surface of the column 115 acquired by the image acquisition unit 309 the area of the bottom surface 121 and the plane 101 becomes bright, and the area of the inclined surface 123 becomes dark.
  • the boundary E ′ between the reflected image in the area of the bottom surface 121 and the reflected image in the area of the inclined surface 123 is clearly shown.
  • FIG. 8 is a diagram showing a path of a light beam for illumination and an image by the light beam.
  • FIG. 8 is a combination of FIGS. 6 and 7.
  • the boundary E ′ is an image obtained by reflection on the side surface of the column 115 of the boundary E between the bottom surface 121 region and the inclined surface 123 region. Therefore, the midpoint of the line segment connecting the point on the boundary E and the corresponding point in the shape of the boundary E ′ corresponds to the position of the point at the periphery of the base of the column 115. In this manner, the position of the base periphery of the pillar 115 can be obtained from the image shown in FIG. A method for obtaining the position of the base periphery of the pillar 115 will be described later.
  • the angle of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 will be described.
  • the unit of angle is degrees.
  • FIG. 9A is a diagram for explaining the relationship between the angle ⁇ of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 and the aperture angle ⁇ of the imaging optical system of the measuring apparatus.
  • ⁇ ⁇ 90- ⁇ Satisfy the relationship. In this case, most of the irradiated light reaches the bottom surface 121 of the groove 120.
  • FIG. 9B is a diagram for explaining the relationship between the angle ⁇ of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 and the aperture angle ⁇ of the imaging optical system of the measuring apparatus.
  • 90- ⁇ ⁇ Satisfy the relationship.
  • some of the irradiated light beams cannot reach the bottom surface 121 of the groove 120 due to vignetting caused by the flat surface 101. Therefore, this state is not preferable from the viewpoint of the efficiency of irradiation.
  • FIG. 10A is a diagram for explaining the relationship between the angle ⁇ of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 and the aperture angle ⁇ of the imaging optical system of the measuring apparatus.
  • ⁇ ⁇ ⁇ Satisfy the relationship In this case, a part of the light beam reflected by the inclined surface 123 enters the measuring device. In this case, the boundary between the region of the bottom surface 121 and the region of the inclined surface 123 becomes unclear in the image obtained by the measuring apparatus. Therefore, this state is not preferable from the viewpoint of measurement by an image.
  • FIG. 10B is a diagram for explaining the relationship between the angle ⁇ of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 and the aperture angle ⁇ of the imaging optical system of the measuring apparatus.
  • ⁇ Satisfy the relationship.
  • the light beam reflected by the inclined surface 123 does not enter the measuring device. Therefore, the boundary between the region of the bottom surface 121 and the region of the inclined surface 123 becomes clear in the image obtained by the measuring apparatus.
  • the angle ⁇ of the inclined surface 123 of the groove 120 with respect to the bottom surface 121 and the aperture angle ⁇ of the imaging optical system of the measuring device satisfy the following relationship.
  • ⁇ ⁇ ⁇ 90- ⁇ Note that the aperture angle ⁇ of the imaging optical system of the measuring apparatus is generally in the range of 10 degrees to 20 degrees. Therefore, the angle of the inclined surface 123 with respect to the bottom surface 121 is preferably 20 degrees to 70 degrees.
  • FIG. 11 is a diagram for explaining the relationship between the width W of the groove 120 and the length L of the column 115.
  • the following relationship needs to be satisfied with the aperture angle of the imaging optical system of the measuring device as ⁇ . is there.
  • the width W is preferably 0.04 mm or more from the viewpoint of the resolution of the measuring apparatus.
  • FIG. 12 is a flowchart for explaining a measurement method according to an embodiment of the present invention.
  • FIG. 13 is a diagram showing the relationship between the measurement method shown in the flowchart of FIG. 12 and the boundaries E and E ′.
  • step S1010 of FIG. 12 in the image of the measurement apparatus, the boundary E is defined from three points on the outer periphery of the groove 120 of the position reference unit 110, that is, the boundary E between the region of the bottom surface 121 and the region of the inclined surface 123. Determine the circle to be formed.
  • step S1020 in FIG. 12 an axis A passing through the center of the circle is determined.
  • the axis A is the horizontal direction.
  • step S1030 of FIG. 12 on the right side of the circle, the intersections of the axis A, the boundary E, and the boundary E ′ are set as A1 and A1 ′.
  • the boundary E ′ is an image obtained by reflection on the side surface of the column 115 of the boundary E between the bottom surface 121 region and the inclined surface 123 region.
  • step S1040 of FIG. 12 the midpoint of the line segment connecting point A1 and point A1 'is AC1.
  • step S1050 in FIG. 12 on the left side of the circle, intersections of the axis A, the boundary E, and the boundary E ′ are set as A2 and A2 ′.
  • step S1060 of FIG. 12 the midpoint of the line segment connecting point A2 and point A2 'is AC2.
  • step S1070 in FIG. 12 the midpoint of the line segment connecting the points AC1 and AC2 is AC.
  • step S1080 in FIG. 12 an axis B orthogonal to the axis A is determined.
  • step S1090 of FIG. 12 for the axis B, the points BC1, BC2, and BC are obtained according to the procedure from step S1030 to step S1070.
  • step S1100 of FIG. 12 the position of the position reference unit 110 is determined from the point AC and the point BC.
  • the main part of the position reference unit 110 is a cylinder, a point having the coordinates of the point AC in the axis A direction and the point BC in the axis B direction is the center of the cross section perpendicular to the cylinder axis. By setting the position, the position of the position reference unit 110 can be determined.
  • the measurement is performed based on the position of the tip end portion of the column of the position reference portion 110 '. For this reason, the deviation of the reference position is caused by the inclination angle of the column.
  • Table 1 is a table showing the deviation of the reference position with respect to the inclination angle of the column for the conventional part and the part of the present invention.
  • the tilt angle of the column is an angle of the axis in the longitudinal direction of the column with respect to the normal line of the plane 101.
  • the unit of length in Table 1 is millimeter.
  • the column length is 2.67 millimeters.
  • FIG. 14 is a diagram showing the deviation of the reference position with respect to the inclination angle of the column for the conventional part and the part of the present invention.
  • the deviation of the conventional part is indicated by a broken line
  • the deviation of the part of the present invention is indicated by a solid line.
  • the deviation of the reference position due to the inclination angle of the column is greatly reduced.
  • a tolerance of lens position ⁇ 3 micrometers can be realized.
  • FIG. 15 is a diagram showing a component 100A including a position reference portion 110A according to another embodiment of the present invention.
  • the two position reference portions 110A have a quadrangular prism shape.
  • the cross section perpendicular to the longitudinal direction of the position reference portion may be circular or polygonal.
  • the cross section of the column corresponding to the length of L from the root described with reference to FIG. 11 needs to have the same shape. Even if the cross section of the column of the position reference portion is polygonal, the position of the position reference portion can be determined by a measurement method similar to the measurement method shown in FIG.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Mechanical Coupling Of Light Guides (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

La présente invention concerne un procédé de mesure de position permettant de déterminer avec une grande précision la position d'une lentille, ou d'un objet analogue, à l'aide d'une partie de référence de position d'un composant. Dans ce procédé de mesure de position, la position d'un point donné sur une image d'un dispositif de mesure pourvu d'un système optique d'imagerie utilisant l'épi-éclairage coaxial est déterminée en utilisant la position d'une partie de référence de position comme référence. Au moins une partie de base de la partie de référence de position présente une forme en colonne. Une rainure d'une largeur fixe se trouve autour de la base de la colonne 115. La surface inférieure 121 de la rainure est parallèle à une surface plate. Une surface inclinée 123 qui s'élève à partir de la surface inférieure à un angle θ par rapport à la surface inférieure et atteint la surface plate se trouve au niveau du bord circonférentiel externe de la surface inférieure. Le procédé de l'invention comprend, sur une image du dispositif de mesure, la détermination de la position du bord circonférentiel de la base de la colonne à partir de la position du bord circonférentiel externe E de la surface inférieure et de la position d'une image réfléchie E' du bord circonférentiel externe, la détermination de la position de la partie de référence de position à partir de la position du bord circonférentiel de la base de la colonne, et la détermination de la position du point donné en utilisant la position de la partie de référence de position comme référence.
PCT/JP2017/017867 2017-05-11 2017-05-11 Procédé et composant de mesure de position WO2018207310A1 (fr)

Priority Applications (7)

Application Number Priority Date Filing Date Title
PCT/JP2017/017867 WO2018207310A1 (fr) 2017-05-11 2017-05-11 Procédé et composant de mesure de position
JP2017239493A JP6989950B2 (ja) 2017-05-11 2017-12-14 位置測定方法及び部品
US15/967,974 US10295754B2 (en) 2017-05-11 2018-05-01 Position determination method and element
CN201810430660.1A CN108896276B (zh) 2017-05-11 2018-05-08 位置测定方法以及部件
CN202111208827.8A CN113933030A (zh) 2017-05-11 2018-05-08 位置测定部件
DE102018111233.5A DE102018111233A1 (de) 2017-05-11 2018-05-09 Positionsbestimmungsverfahren und -element
JP2021190918A JP7244954B2 (ja) 2017-05-11 2021-11-25 位置測定方法及び部品

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2017/017867 WO2018207310A1 (fr) 2017-05-11 2017-05-11 Procédé et composant de mesure de position

Publications (1)

Publication Number Publication Date
WO2018207310A1 true WO2018207310A1 (fr) 2018-11-15

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PCT/JP2017/017867 WO2018207310A1 (fr) 2017-05-11 2017-05-11 Procédé et composant de mesure de position

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JP (1) JP6989950B2 (fr)
WO (1) WO2018207310A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007317845A (ja) * 2006-05-25 2007-12-06 Elpida Memory Inc 半導体装置の製造方法
JP2008216905A (ja) * 2007-03-07 2008-09-18 Sony Corp 光モジュール及び光導波路の製造方法
JP2009145656A (ja) * 2007-12-14 2009-07-02 Enplas Corp 光結合素子およびこれを備えた光モジュール
JP2014137410A (ja) * 2013-01-15 2014-07-28 Furukawa Electric Co Ltd:The 光モジュール、光モジュールの製造方法
US20140294354A1 (en) * 2013-04-02 2014-10-02 Hon Hai Precision Industry Co., Ltd. Optical connector with alignment device

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07157144A (ja) * 1993-12-10 1995-06-20 Furukawa Electric Co Ltd:The 光部品の寸法測定方法
JP4845333B2 (ja) 2003-04-11 2011-12-28 株式会社リコー 光電変換素子パッケージ、その作製方法及び光コネクタ
JP2007256372A (ja) 2006-03-20 2007-10-04 Sumitomo Electric Ind Ltd 光ファイバ接続部品
WO2014157363A1 (fr) 2013-03-27 2014-10-02 京セラ株式会社 Module de transmission optique, module de transmission composite photoélectrique, et connecteur optique
JP2014228585A (ja) 2013-05-20 2014-12-08 株式会社フジクラ 光モジュールの製造方法及び光モジュール

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007317845A (ja) * 2006-05-25 2007-12-06 Elpida Memory Inc 半導体装置の製造方法
JP2008216905A (ja) * 2007-03-07 2008-09-18 Sony Corp 光モジュール及び光導波路の製造方法
JP2009145656A (ja) * 2007-12-14 2009-07-02 Enplas Corp 光結合素子およびこれを備えた光モジュール
JP2014137410A (ja) * 2013-01-15 2014-07-28 Furukawa Electric Co Ltd:The 光モジュール、光モジュールの製造方法
US20140294354A1 (en) * 2013-04-02 2014-10-02 Hon Hai Precision Industry Co., Ltd. Optical connector with alignment device

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JP6989950B2 (ja) 2022-01-12

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