JP2018189517A - Measurement device and method for manufacturing articles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measurement device which is advantageous in terms of size.SOLUTION: The measurement device includes an illumination unit for irradiating an inspection target surface with light from a light source, and measures the reflection characteristics of the inspection target surface based on light reflected from the inspection surface illuminated by the illumination unit. The illumination unit includes a first mirror part with a first reflection surface and a second mirror part with a second reflection surface, the second reflection surface being located on an ellipse or on a parabola with a point on the inspection target surface as the focal point. The first reflection surface is movable so that light can be selectively collected to one point at one of different incident angles through the second reflection surface.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a measuring device and an article manufacturing method.

  A measuring device for measuring the reflection characteristics (glossiness, haze value, etc.) of a surface to be measured is known. Patent Document 1 discloses an apparatus for measuring the glossiness of a test surface.

Japanese Patent No. 3347818

  To measure the reflection characteristics for each incident angle of light with respect to the surface to be measured, it is necessary to provide multiple sets of light sources and sensors for detecting reflected light, or to provide a mechanism for moving the light sources and sensors. Can be disadvantageous.

  An object of the present invention is to provide a measuring device that is advantageous in terms of size, for example.

  In order to solve the above problems, the present invention has an illumination unit that illuminates a test surface with light from a light source, and reflects the test surface based on reflected light from the test surface illuminated by the illumination unit. A measurement device for measuring characteristics, wherein the illumination unit includes a first mirror unit having a first reflection surface and a second mirror unit having a second reflection surface, and the second reflection surface is a test object. The first reflecting surface is selectively on at one of a plurality of incident angles different from each other via the second reflecting surface. The first reflecting surface is on an ellipse or a parabola with a point on the surface as a focal point. It is movable so that it may enter.

  According to the present invention, for example, a measuring device advantageous in terms of size can be provided.

It is a figure which shows the structure of the measuring device which concerns on 1st Embodiment. It is a figure which shows the structure of the measuring device which concerns on 2nd Embodiment. It is a figure which shows the structure of the measuring device which concerns on 3rd Embodiment. It is a figure which shows the structure of the measuring device which concerns on 5th Embodiment. It is a figure which shows the structure of the optical system which suppresses the influence of a stray light.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, in each drawing, the same reference number is attached | subjected about the same member thru | or element, and the overlapping description is abbreviate | omitted.
[First Embodiment]

<Measurement device>
FIG. 1 is a diagram illustrating a configuration of a measurement apparatus 100 according to the present embodiment. The measuring apparatus 100 irradiates light at a plurality of angles with respect to the test surface of the test object W, and receives the reflected light reflected from the test surface at a plurality of reflection angles. The measuring apparatus 100 obtains the reflection characteristics based on information regarding the irradiation angle, the light receiving angle, and the light intensity of the received light. In the present embodiment, the reference for the irradiation angle and the light receiving angle is a normal to the surface to be measured.

  The reflection characteristics include, for example, glossiness, haze value, image clarity, and BRDF (Bidirectional Reflection Distribution Function). The measurement apparatus 100 includes an illumination unit 110, a light receiving unit 120, a detection unit 130, and a processing unit 140.

(Lighting part)
The illumination unit 110 includes a power source 111, a light source 112, a lens 113, a first mirror unit 114, and a second mirror unit 115. The illumination unit 110 illuminates the test surface of the test object W at a plurality of angles. The power source 111 outputs a drive current to the light source 112.

  In the present embodiment, a white LED is used as the light source 112. In addition, an incandescent lamp, a fiber laser, a semiconductor laser, or the like may be used. In order to obtain information on a specific color, a semiconductor laser having a specific wavelength can be used. A light source having a plurality of different single wavelengths may be switched and used.

  The light output from the light source 112 is converted into a parallel beam by the lens 113 and enters the first mirror unit 114. The light that has entered the first mirror unit 114 is reflected by the reflection surface of the first mirror unit 114 (referred to as the first reflection surface), and enters the reflection surface (second reflection surface) of the second mirror unit 115. The light reflected by the second reflecting surface is irradiated on the test surface.

The first reflective surface, light outputted from a light source, through the second reflecting surface, a point f ₂ on the test surface, to selectively incident at any of a plurality of different incident angles It is movable. The first mirror unit 114 is, for example, a galvanometer mirror, and includes a flat mirror having a first reflecting surface and an illumination side driving unit 1141 that moves the first reflecting surface. The illumination side drive unit 1141 rotates the first reflecting surface around an axis parallel to the first reflecting surface. The illumination angle is adjusted by moving the reflecting surface by the illumination side driving unit 1141.

  The first mirror unit 114 is not limited to a galvanometer mirror, and a mirror with a mirror attached to the rotating shaft of a motor or a mirror that manually adjusts the angle can also be used. Each reflection surface can be rotated by synchronizing the illumination side driving unit 1141 and a light receiving side driving unit 1221 described later.

In the present embodiment, the second mirror unit 115 includes a plane mirror 115A, a plane mirror 115B, and a plane mirror 115C. Each of the reflecting surfaces (second reflecting surfaces) of the plurality of plane mirrors included in the second mirror unit 115 is a first ellipse whose focal point is the point f ₁ on the first reflecting surface and the point f ₂ on the surface to be examined. It is disposed on ellipse E _1.

  In the present embodiment, the plane mirror 115A illuminates the test surface at 20 degrees, the plane mirror 115B illuminates the test surface at 60 degrees, and the plane mirror 115C illuminates the test surface at 85 degrees.

(Light receiving section)
The light receiving unit 120 includes a third mirror unit 121, a fourth mirror unit 122, and a lens 123. The lens 123 adjusts the wavefront of the reflected light reflected by the fourth mirror unit 122 and guides the adjusted reflected light to the detection unit 130.

In the present embodiment, the third mirror unit 121 includes a plane mirror 121A, a plane mirror 121B, and a plane mirror 121C. The reflection surfaces (referred to as third reflection surfaces) of the plurality of plane mirrors included in the third mirror unit 121 are the point f ₃ on the reflection surface (fourth reflection surface) of the fourth mirror unit 122 and the test surface. a point f ₂ above is disposed on the second ellipse ellipse E ₂ to focus. Note that the second ellipse E ₂ are the first ellipse E _1, not limited to the same size. In the case of the same size, it is possible to use optical components of a plane mirror having the same design. In the case of different sizes, it is possible to design the device shape according to the measurement object.

  In the present embodiment, the plane mirror 121A receives reflected light of 20 degrees, the plane mirror 121B receives reflected light of 60 degrees, and the plane mirror 115C receives reflected light of 85 degrees. Note that the irradiation angle and the light receiving angle do not have to coincide with each other. For example, the reflected light of the light that illuminates the test surface at an irradiation angle of 60 degrees may be received at an angle of 85 degrees.

The fourth mirror unit 122 receives the reflected light selectively from the point f ₂ on the surface to be measured via the third reflecting surface at any one of a plurality of different reflection angles. Rotate the reflective surface. The fourth mirror unit 122 is, for example, a galvanometer mirror, and includes a flat mirror having a fourth reflecting surface and a light receiving side driving unit 1221 that moves the fourth reflecting surface. The light receiving side driving unit 1221 rotates the fourth reflecting surface around an axis parallel to the fourth reflecting surface. The light receiving angle is adjusted by moving the reflecting surface by the light receiving side driving unit 1221. The fourth mirror unit 122 may also use a mirror including a driving unit other than the galvanometer mirror.

(Detection unit and processing unit)
The detection unit 130 includes a detection surface that receives reflected light, and detects the light intensity on the detection surface. As the detection unit 130, for example, a two-dimensional sensor such as a line sensor or a photodetector can be used. A signal related to the light intensity detected by the detection unit 130 is output to the processing unit 140.

  The processing unit 140 holds control information of the illumination side driving unit 1141 and the light receiving side driving unit 1221 and can control each driving unit. The control information can be input from the outside through an input unit (not shown). The processing unit 140 obtains the reflection characteristics of the test surface based on the received signal, the irradiation angle, and the light receiving angle.

As described above, the measuring apparatus 100 according to the present embodiment can measure the reflection characteristics of the test surface at a plurality of irradiation angles and light receiving angles without increasing or moving the light source or the detection unit (sensor). That is, the measurement apparatus 100 of this embodiment is advantageous in terms of the apparatus size, for example.
[Second Embodiment]

In the first embodiment, a plurality of plane mirrors are used for the second mirror unit 115 and the third mirror unit 121. In the present embodiment, the number of optical members can be reduced as compared with the first embodiment by using one elliptical mirror whose reflecting surface is an elliptical surface instead of the plurality of flat mirrors. FIG. 2 is a diagram illustrating a configuration of the measurement apparatus 200 according to the present embodiment. The illumination unit 210 of the measuring device 200 includes a second mirror unit 215 that is an elliptical mirror. In addition, the light receiving unit 220 includes a third mirror unit 221 that is an elliptical mirror. According to the measurement apparatus 200 of the present embodiment, it is possible to measure at an arbitrary irradiation angle and light reception angle by rotating the illumination light by rotating the first reflecting surface, and the same effects as in the first embodiment can be obtained. can get. In addition, you may use an elliptical mirror for either one of an illumination part and a light-receiving part. Moreover, you may use an elliptical mirror and a plane mirror together.
[Third Embodiment]

A parabolic mirror having a reflecting surface on a parabola may be used for the light receiving unit. In this case, the mirror on the light receiving unit side can be reduced. FIG. 3 is a diagram illustrating a configuration of the measurement apparatus 300 according to the present embodiment. The measuring apparatus 300 includes a light receiving unit 320 that is a parabolic mirror, and a detection unit 330. The focus of the parabolic mirror of the light receiving portion 320 is coincident with the point f _2. The reflective surface may be a plurality of flat surfaces on the parabola.

  The detection unit 330 is disposed at a position where the parallel light reflected from the light receiving unit 320 is received. In the present embodiment, a two-dimensional sensor having a size of one pixel of 24 μm × 24 μm, a number of pixels of 512 × 512 pixels, and an overall size of 12.3 × 12.3 mm is used as the detection unit 330. When the irradiation angle is in the range of 10 degrees to 85 degrees, the shape of the parabolic mirror is determined as described below.

Point f ₂ as the origin, x axis parallel to the test surface, an axis perpendicular to the y-axis. Then, the lowermost side of the detection unit 330 is positioned at a height of 8.85 mm from the test surface. X-coordinate _{x 85} position _{P 85} where the light reflected in the direction of 85 degrees from the test surface hits the light receiving unit 320, when the y coordinate of the position _{P 85} to 10 mm, is obtained by the following equation (1).

From Equation (1), xy coordinates of the position _{P 85} is (114.3,10). The use area of the detection unit 330 is 10 mm × 10 mm, and the y coordinate of the position P ₁₀ at which the light reflected in the direction of 10 degrees from the test surface hits the light receiving unit 320 is 20 mm. X-coordinate _{x 10} position _{P 10} is determined by the following equation (2).

From Equation (2), xy coordinates of the position _{P 10} is (3.5,20). From the above, the shape of the parabolic mirror is a parabolic shape having a parabola that satisfies the conditions of the focal point (0, 0), P ₈₅ , and P ₁₀ . Assuming that the parabola is symmetric with respect to the x-axis, the parabola formula is expressed by the following mathematical formula (3).

  By using a parabolic mirror having a shape determined by Equation (3) as the light receiving unit 320, light is incident on the detection unit 330 vertically. When the angle of the reflected light (light receiving angle) is ψ, the relationship between the angle ψ and the y coordinate of the detection unit 330 is expressed by the following formula (4).

Based on Equation (4), information regarding the light reception angle can be obtained from the coordinates on the sensor of the detection unit 330. In this embodiment, the paraboloid of the parabolic mirror is a paraboloid symmetric with respect to the x axis. However, a contrasting paraboloid in a coordinate system in which the x axis and the y axis are rotated may be used. In such a case, the distance between the two-dimensional sensor and the parabolic mirror can be changed. Moreover, you may use the parabolic surface mirror from which a magnitude | size and a shape differ according to the difference in the specification of a sensor. The measuring apparatus 300 of this embodiment also has the same effect as that of the first embodiment.
[Fourth Embodiment]

  In the third embodiment, information related to the light reception angle can be obtained from the coordinates on the sensor of the detection unit 330 based on Expression (4). In this embodiment, when the elliptical mirror as in the second embodiment is used for the light receiving unit and the detection unit is arranged in the same manner as in the third embodiment, the coordinates on the sensor of the detection unit are set to a predetermined linear function. To obtain information about the light receiving angle.

One focus of the ellipse mirror of the third mirror 221 to a point f _2, and the other a point on the detector 330 of FIG. 3 (a point on the y-axis). The reflection surface of the elliptical mirror is expressed by Equation (5), where b is the major axis and a is the minor axis.

  Further, the y coordinate of the point on the detection unit 330 is expressed by Equation (6).

Assuming that the reflected light is incident perpendicular to the sensor surface of the detection unit 330, the coordinate x on the elliptical mirror is expressed by Equation (7). φ is the same angle as in the third embodiment.

  Using these equations, the relationship between a, b, and y is obtained as follows.

Based on the above formula, the coordinates on the sensor of the detection unit can be associated with information on the light reception angle.
[Fifth Embodiment]

  FIG. 4 is a diagram illustrating a configuration of a measurement apparatus 500 according to the fifth embodiment. The measurement device 500 of the present embodiment differs from the measurement device 300 of the third embodiment in the configuration on the light receiving unit side. The measurement device 500 includes a light receiving unit 520 and a detection unit 530. The light receiving unit 520 includes a parabolic mirror 521 and a folding mirror 522.

The folding mirror 522 is disposed on the optical path between the detection unit 530 and the parabolic mirror 521, and the direction in which the light reflected by the parabolic mirror 521 travels is folded, for example, 90 degrees toward the light receiving unit 530. . Incidentally, parabolic mirror 521 of the present embodiment is a point f ₂ a focal, the third embodiment reflects the incident light in different directions. According to the present embodiment, it is possible to avoid that the optical path of the irradiation light is hindered by the thickness of the detection unit 530, wiring, or the like.
[Modification]

  Note that the surface of the test object may have a layer structure due to a coating or foreign matter, or stray light may occur due to leakage light, multiple reflection within the apparatus, or the like. In this case, the influence of stray light can be suppressed by arranging the aperture in front of the detection unit. FIG. 5 is a diagram illustrating a configuration of an optical system that suppresses the influence of stray light. As shown in FIG. 5, a parallel light lens 630, an aperture 620, and a condenser lens 610 are arranged on the detection surface side of the detection unit 640 in order from the detection surface side.

  The stray light is collected at a point different from the point where the reflected light (parallel light) from the test surface is collected by the condenser lens 610. Therefore, stray light can be reduced by arranging the parallel light lens 630 through the aperture 620. In this embodiment, the condensing lens 610 is used, but a reflecting lens using a curved mirror may be used. By using a reflective lens, the influence of aberration can be reduced.

  A parabolic mirror may be arranged in a dome shape on the light receiving part side so as to surround the test object W. According to this arrangement, reflected light in all directions can be received.

  Moreover, you may use a parabolic mirror for the illumination part side. In this case, the light irradiated on the parabolic mirror is scanned on the parabolic mirror while the parallelism of the optical axis is maintained by the two-dimensional beam shifter. Furthermore, the optical system that controls the wavefront of the light is used so that the light irradiated onto the test surface becomes parallel light. Moreover, you may translate light by rotation of a 1st reflective surface.

  An elliptical spherical mirror may be arranged in a dome shape on the illumination unit side so as to surround the test object W. Light irradiated on the elliptical spherical mirror is scanned in various directions by a two-dimensional beam scanner. Furthermore, the optical system that controls the wavefront of the light is used so that the light irradiated onto the test surface becomes parallel light. A two-dimensional beam scanner is disposed at one focal point of the elliptical spherical surface, and a test surface is disposed at the other focal point.

(Embodiment related to article manufacturing method)
The measuring device according to the embodiment described above can be used in an article manufacturing method. The article manufacturing method may include a step of measuring the reflection characteristic of the test surface of the object using the measuring device, and a step of processing the object whose reflection characteristic is measured in the step. The process can include, for example, at least one of processing, cutting, inspection, assembly, and selection. More specifically, for example, the reflection characteristic of the surface of the painted object is measured, and the obtained measurement value is compared with the reference value. Based on the result of the comparison, an object is selected (for example, if the measured value does not fall within the allowable range, the object is determined to be defective). Alternatively, based on the result of the comparison, feedback relating to the painting conditions is performed in the painting process of the object. Since the article manufacturing method of the present embodiment measures the reflection characteristics of the surface of an object with the measuring device, it is advantageous in at least one of the performance, quality, productivity, and production cost of the article compared to the conventional method. It is.

(Other embodiments)
As mentioned above, although embodiment of this invention has been described, this invention is not limited to these embodiment, A various change is possible within the range of the summary.

DESCRIPTION OF SYMBOLS 100 Measuring apparatus 110 Illumination part 114 1st mirror part 1141 Illumination side drive part 115 2nd mirror part 120 Light reception part 121 3rd mirror part 122 4th mirror part 1222 Light reception side drive part 130 Detection part 140 Processing part

Claims (19)

A measuring device that includes an illuminating unit that illuminates a test surface with light from a light source, and that measures reflection characteristics of the test surface based on reflected light from the test surface illuminated by the illuminating unit; ,
The illumination unit includes a first mirror unit having a first reflection surface, and a second mirror unit having a second reflection surface,
The second reflecting surface is on an ellipse or a parabola with a point on the test surface as a focal point,
The first reflection surface is movable so that the light selectively enters the point through the second reflection surface at any one of a plurality of different incident angles.
A measuring device characterized by that.   The measuring apparatus according to claim 1, wherein the first reflecting surface is a flat surface.   The measuring apparatus according to claim 1, wherein the first mirror rotates the first reflecting surface so as to switch an incident angle of light to the focal point.   The measuring apparatus according to claim 1, wherein the second reflecting surface is a plurality of planes on the ellipse.   The measuring apparatus according to claim 1, wherein the second reflecting surface is an ellipsoid including the ellipse.   The measuring apparatus according to claim 4, wherein the light is rotated by rotation of the first reflecting surface.   The measuring apparatus according to claim 1, wherein the second reflecting surface is a plurality of planes on the parabola.   The measuring apparatus according to claim 1, wherein the second reflecting surface is a parabolic surface including the parabola.   The measuring apparatus according to claim 7, wherein the light is translated by rotation of the first reflecting surface. A detection unit that receives the reflected light, and detects a light intensity on the detection surface;
A light receiving portion for guiding the reflected light to the detection surface,
The light receiving unit includes a third mirror unit having a third reflecting surface, and a fourth mirror unit having a fourth reflecting surface,
The third reflecting surface is on an ellipse or a parabola with the point as a focus,
The measuring apparatus according to claim 1, wherein the measuring apparatus is one of the following.   The measuring apparatus according to claim 10, wherein the fourth reflecting surface is a flat surface.   The measuring apparatus according to claim 10, wherein the third reflecting surface is a plurality of planes on the ellipse.   The measuring apparatus according to claim 10, wherein the third reflecting surface is an ellipsoid including the ellipse.   The measuring apparatus according to claim 10, wherein the third reflecting surface is a plurality of planes on the parabola.   The measuring apparatus according to claim 10, wherein the third reflecting surface is a parabolic surface including the parabola.   The fourth mirror unit receives the fourth reflection surface so as to selectively receive the reflected light from the point through any of a plurality of different reflection angles via the third reflection surface. The measuring device according to any one of claims 12 to 15, wherein the measuring device is rotated. A detection unit that receives the reflected light, and detects a light intensity on the detection surface;
A light receiving section for guiding the reflected light to the detection surface,
The light receiving unit has a third reflecting surface, and the third reflecting surface is on a parabola with the point as a focus.
The measuring apparatus according to claim 1, wherein the measuring apparatus is one of the following.   The measurement apparatus according to claim 17, further comprising a folding mirror between the detection surface and the third reflection surface. A method for manufacturing an article, comprising:
A reflection characteristic of an object surface to be measured is measured using the measurement device according to any one of claims 1 to 18,
The article is manufactured by processing the measured object.
The manufacturing method characterized by the above-mentioned.

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