JP6695747B2 - measuring device - Google Patents

Description

  The present invention relates to a measuring device that measures an object to be measured.

  In the triangulation type measuring device, the surface of the measuring object is irradiated with light, and the reflected light is received by a light receiving element having pixels arranged one-dimensionally or two-dimensionally. The height of the surface of the measuring object can be measured based on the peak position of the received light amount distribution obtained by the light receiving element.

  Non-Patent Document 1 proposes a shape measurement by a triangulation method that combines coded light and a phase shift method. Further, Non-Patent Document 2 proposes shape measurement by a triangulation method that combines coded light and stripe light. In these methods, the accuracy of shape measurement of the measurement object can be improved.

Toni F. Schenk, "Remote Sensing and Reconstruction for Three-Dimensional Objects and Scenes", Proceedings of SPIE, Volume 2572, pp. 1-9 (1995) Sabry F. El-Hakim and Armin Gruen, "Videometrics and Optical Methods for 3D Shape Measurement", Proceedings of SPIE, Volume 4309, pp. 219-231 (2001)

  Based on the data obtained by the shape measurement as described above (hereinafter, referred to as measurement data), the dimensions and the like of a desired portion of the measurement object can be calculated. For example, an image showing the three-dimensional shape of the measurement target is displayed based on the measurement data. The user designates a measurement location on the displayed image, and the measurement value at the designated location is calculated from the measurement data.

  However, unless the reflected light at the measurement location of the measurement object is received by the light receiving element, the measurement data at the measurement location cannot be obtained and the measurement value cannot be obtained. Depending on the shape of the measurement object, it is necessary to hold the measurement object in a fixed posture by using a jig or the like in order to obtain necessary measurement data. In that case, a complicated work is required for the user. In particular, a user who is unfamiliar with the work requires a great deal of labor and time.

  An object of the present invention is to provide a measuring device that can easily acquire a measurement value at a desired location.

(1) A measuring device according to the present invention has a stage holding part and a non-tilted mounting surface which is held by the stage holding part so as to be rotatable about a vertical rotation axis and which is orthogonal to the rotation axis. One part of the inclined mounting surface is configured to be changeable between a non-inclined state orthogonal to the rotation axis and an inclined state not orthogonal to the rotation axis. A stage that selectively forms an inclined mounting surface to be placed, a light projecting unit that irradiates a measuring object having a pattern onto the measuring object that is mounted on the stage, and receives the measuring light reflected by the measuring object. And a head unit including a light receiving unit that outputs a light receiving signal that indicates the amount of received light, and the measuring light is guided obliquely downward from the light emitting unit to the measurement target, and the optical axis of the light receiving unit is directed to the measurement target. Based on a light receiving signal output from the light receiving unit and a connecting unit that fixedly connects the head unit and the stage holding unit so as to extend obliquely downward toward the point group data representing the three-dimensional shape of the measurement target. Point cloud data generating means for generating, combining means for generating combined point cloud data by combining one point cloud data generated by the point cloud data generating means and another point cloud data, and a measuring object And a measuring unit that receives a designation of a location to be measured and calculates a measurement value of the designated location based on the composite point cloud data generated by the synthesizing unit.

  In this measuring device, the head unit including the light projecting unit and the light receiving unit is fixedly connected to the stage holding unit. The measuring object is placed on the inclined mounting surface of the stage held by the stage holding section, and the measuring light having a pattern is applied to the measuring object from the light projecting section. The measurement light reflected by the measurement object is received by the light receiving unit, and a light reception signal indicating the amount of received light is output. Point cloud data representing the three-dimensional shape of the measurement target is generated based on the light reception signal.

  In this case, since the light projecting unit, the light receiving unit, and the stage are integrally provided, the user does not need to adjust their arrangement, and the object to be measured is placed on the stage to measure the object to be measured. Object point cloud data can be obtained. Further, since the measurement object is placed on the inclined mounting surface that is non-perpendicular to the vertical rotation axis, it is possible to maintain the measurement object in an inclined posture without using a jig or the like. It is possible to easily obtain the point cloud data of a location.

  Further, since the rotation axis of the stage is not parallel to the optical axis of the light receiving section, the position of the measurement target pointed at the light receiving section changes when the stage is rotated. Therefore, the measurement light is irradiated onto the measurement target in a state where the rotational position of the stage is different, and thus the reflected light at the different position of the measurement target is received by the light receiving unit. Therefore, by rotating the stage, it is possible to generate point cloud data at different locations on the measurement target.

  The synthesized point cloud data is generated by synthesizing the generated plurality of point cloud data. The synthetic point cloud data includes three-dimensional shapes of various points of the measurement target represented by the plurality of point cloud data. Therefore, it is possible to easily acquire the measurement value of a desired portion of the measurement object based on the generated composite point cloud data.

(2) The stage may have another non-tilted mounting surface different from the one portion, and may have a locking portion for locking the measurement object mounted on the tilted mounting surface. ..

(3) The stage has a non-inclined mounting surface, a stage plate held by the stage holding portion, and an inclined mounting portion which has an inclined mounting surface as one part and is attachable to and detachable from the stage plate. May be included. In this case, the non-tilted mounting surface and the inclined mounting surface can be easily switched by attaching and detaching the inclined portion to and from the stage plate.

(4) One part of the stage may be provided so that the tilt angle with respect to the plane perpendicular to the rotation axis can be adjusted so as to selectively form the tilt mounting surface . In this case, the tilted mounting surface can be easily switched between the non-tilted mounting surface and the tilted mounting surface by adjusting the tilt angle of one portion of the stage.

  (5) The measuring device further includes rotation control means for controlling the rotation of the stage, and the point cloud data generation means is output by the light receiving unit when the rotation control means positions the stage at the first rotation position. One point group data is generated based on the light receiving signal, and another point group data is generated based on the light receiving signal output by the light receiving unit when the stage is positioned at the second rotation position by the rotation control means. The combining means may combine one point cloud data and another point cloud data based on the rotational position of the stage controlled by the rotation control means.

  In this case, based on the rotational position of the stage controlled by the rotation control means, the positional relationship between the part of the measurement object represented by the point cloud data and the part of the measurement object represented by the other point cloud data is specified. can do. Thereby, one point cloud data and another point cloud data can be easily combined.

  (6) The light receiving section may have an image pickup surface perpendicular to the optical axis, and the rotation control section may control the rotation position of the stage so that the inclined mounting surface faces the image pickup surface of the light receiving section. .. In this case, it is possible to efficiently generate the point cloud data of the required portion of the measurement target.

  (7) The measuring device may further include an invalid portion setting unit that sets a portion to be invalidated in the synthetic point cloud data generated by the synthesizing unit. In this case, an unnecessary portion of the composite point cloud data can be invalidated. This makes it easy to specify the measurement location.

  (8) The measuring apparatus includes a stereoscopic shape image data generating unit that generates stereoscopic image data representing an image of the measurement object viewed in an arbitrary direction based on the synthetic point cloud data generated by the synthesizing unit, and the synthesizing unit. Reference point setting means for setting a reference surface corresponding to a part of the surface of the measurement object represented by the combined point cloud data generated by the above, and the combined point cloud data generated by the combining means Based on, further comprises a reference surface image data generating means for generating reference surface image data representing an image of the measurement object viewed perpendicular to the reference surface set by the reference surface setting means, the measuring means, The designation of the location to be measured may be accepted for either one of the three-dimensional shape image data and the reference plane image data.

  In this case, the user can intuitively recognize the three-dimensional shape of the measuring object by looking at the image represented by the three-dimensional image data. Further, the user can easily specify the measurement location by using the image represented by the reference plane image data. Therefore, the required measurement value can be efficiently obtained by using the three-dimensional shape image data and the reference plane image data in order or selectively.

  According to the present invention, it is possible to easily acquire the measurement value of a desired portion of the measurement object.

It is a block diagram which shows the structure of the measuring device which concerns on one embodiment of this invention. It is a schematic diagram which shows the structure of the measurement part of the measuring device of FIG. 2 is a functional block diagram showing functions realized by the CPU of FIG. 1. FIG. It is a typical external appearance perspective view of a measurement part. It is a figure for demonstrating the positional relationship of a light-receiving part and a stage. It is a figure for explaining a concrete example of composition of a stage. It is a figure for demonstrating the inclination of an inclination part. It is a figure for explaining the principle of a triangulation method. It is a figure for demonstrating the 1st pattern of measurement light. It is a figure for demonstrating the 2nd pattern of measurement light. It is a figure for demonstrating the 3rd pattern of measurement light. It is a figure which shows the relationship with the timing which imaged the image in the specific part of a measuring object, and the intensity | strength of the light received. It is a figure for demonstrating the 4th pattern of measurement light. It is a figure for demonstrating the example which produces | generates several solid shape data by imaging a to-be-measured object from a some viewpoint. It is a flowchart which shows the procedure of preparation for shape measurement. It is a flow chart which shows the details of the 1st adjustment in the procedure of preparation for shape measurement. It is a flow chart which shows the details of the 1st adjustment in the procedure of preparation for shape measurement. It is a flow chart which shows the details of the 2nd adjustment in the procedure of preparation for shape measurement. It is a flow chart which shows an outline of shape measurement processing. It is an appearance perspective view showing an example of a measuring object. It is a figure which shows the state in which the measuring object of FIG. 20 was mounted on the stage. It is a figure which shows the state in which the measuring object of FIG. 20 was mounted on the stage. It is a figure which shows the example of the target object image based on the synthetic | combination stereoscopic shape data produced | generated in the inclination state. It is a figure for explaining an example of setting an invalid part. It is a figure which shows the example of the target image from which the unnecessary part was removed. 6 is a flowchart showing an operation example of a CPU when setting a reference plane. It is a figure which shows the example of a reference plane image. It is a figure for explaining an example of setting measurement conditions. It is a figure which shows the other example of a reference plane image. It is a figure for demonstrating specification of the part which should acquire a profile. It is a figure which shows the example of a profile image. It is a figure which shows the relationship between the light-receiving part, a stage, and a measuring object in a facing state. It is a figure for explaining other examples of composition of a stage. It is a figure for explaining other examples of composition of a stage.

  Hereinafter, a measuring device according to an embodiment of the present invention will be described with reference to the drawings.

[1] Configuration of Measuring Apparatus FIG. 1 is a block diagram showing the configuration of the measuring apparatus according to one embodiment of the present invention. FIG. 2 is a schematic diagram showing the configuration of the measuring unit of the measuring device 500 shown in FIG. Hereinafter, the measuring device 500 according to the present embodiment will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the measurement device 500 includes a measurement unit 100, a PC (personal computer) 200, a control unit 300, and a display unit 400.

  As shown in FIG. 1, the measurement unit 100 is, for example, an image pickup device integrated with light projection and light reception, and includes a light projection unit 110, a light reception unit 120, an illumination light output unit 130, a stage 140, and a control board 150. As shown in FIG. 2, the light projecting unit 110 includes a measurement light source 111, a pattern generating unit 112, and a plurality of lenses 113 and 114. The light receiving unit 120 includes a camera 121 having an image sensor 121a and a lens 122. In this example, the camera 121 is a monocular camera. The measuring object S is placed on the stage 140.

  In the example of FIG. 2, the measuring unit 100 includes two light projecting units 110. Hereinafter, when distinguishing the two light projecting units 110, one light projecting unit 110 is referred to as a light projecting unit 110A, and the other light projecting unit 110 is referred to as a light projecting unit 110B. The light projecting units 110A and 110B are arranged symmetrically with the optical axis A1 of the light receiving unit 120 interposed therebetween. The optical axis A1 of the light receiving unit 120 passes through the center of the image sensor 121a of the camera 121 and the center of the lens 122.

  The measurement light source 111 of each of the light projecting units 110A and 110B is, for example, a blue LED (light emitting diode). The measurement light source 111 may be another light source such as a halogen lamp. Light emitted from the measurement light source 111 (hereinafter, referred to as measurement light) is appropriately condensed by the lens 113 and then enters the pattern generation unit 112.

  The pattern generation unit 112 is, for example, a DMD (digital micromirror device). The pattern generation unit 112 may be an LCD (liquid crystal display), an LCOS (Liquid Crystal on Silicon) or a mask. The measurement light that has entered the pattern generation unit 112 is converted into a preset pattern and a preset intensity (brightness) and then emitted. The measurement light emitted by the pattern generation unit 112 is converted by the lens 114 into light having a diameter larger than the dimension of the measurement target S, and then the measurement target S on the stage 140 is irradiated with the measurement light.

  The measurement light source 111, the lens 113, and the pattern generation unit 112 of the light projecting unit 110A are arranged so as to be aligned substantially parallel to the optical axis A1 of the light receiving unit 120. Similarly, the measurement light source 111, the lens 113, and the pattern generation unit 112 of the light projecting unit 110B are arranged so as to be aligned substantially parallel to the optical axis A1 of the light receiving unit 120. On the other hand, the lenses 114 of the light projecting units 110A and 110B are arranged so as to be offset with respect to the measurement light source 111, the lens 113, and the pattern generating unit 112. As a result, the optical axes A2 of the light projecting units 110A and 110B are inclined with respect to the optical axis A1 of the light receiving unit 120, and measurement light is emitted toward the measurement target S from both sides of the light receiving unit 120. The measurement light reflected above the stage 140 by the measurement target S is condensed and imaged by the lens 122 of the light receiving unit 120, and is received by the image pickup element 121a of the camera 121.

  In this example, in order to widen the irradiation range of the measurement light, the light projecting units 110A and 110B are configured to have a constant angle of view. The angle of view of the light projecting units 110A and 110B is determined by the size of the pattern generating unit 112 and the focal length of the lens 114, for example. Further, in order to widen the visual field (imaging range) of the light receiving unit 120, the light receiving unit 120 is configured to have a constant angle of view. The angle of view of the light receiving unit 120 is determined by, for example, the size of the image sensor 121a and the focal length of the lens 122. If it is not necessary to widen the irradiation range and the imaging range of the measurement light, a telecentric optical system having an angle of view of approximately 0 degrees may be used as the light projecting units 110A and 110B and the light receiving unit 120.

  The measurement unit 100 may include a plurality of light receiving units 120 having different magnifications. In this case, the measurement object S can be imaged at different magnifications by selectively using the plurality of light receiving units 120. The optical axes of the plurality of light receiving units 120 are preferably parallel to each other.

  The camera 121 is, for example, a CCD (charge coupled device) camera. The image pickup device 121a is, for example, a monochrome CCD (charge coupled device). The image sensor 121a may be another image sensor such as a CMOS (complementary metal oxide semiconductor) image sensor. From each pixel of the image sensor 121a, an analog electric signal (hereinafter referred to as a light reception signal) corresponding to the amount of light received is output to the control board 150.

  Unlike a color CCD, a monochrome CCD does not need to be provided with a pixel that receives light of a red wavelength, a pixel that receives light of a green wavelength, and a pixel that receives light of a blue wavelength. Here, when a specific wavelength such as a blue wavelength is adopted as the measurement light, the color CCD can only be used for measurement of pixels that receive light of the specific wavelength, but the monochrome CCD has no such restriction. Therefore, the measurement resolution of the monochrome CCD is higher than that of the color CCD. Further, unlike the color CCD, the monochrome CCD does not need to be provided with a color filter for each pixel. Therefore, the sensitivity of the monochrome CCD is higher than that of the color CCD. For these reasons, the camera 121 in this example is provided with a monochrome CCD.

  In this example, the illumination light output unit 130 outputs the red wavelength light, the green wavelength light, and the blue wavelength light to the measurement target S in a time division manner. With this configuration, a color image of the measuring object S can be captured by the light receiving unit 120 using the monochrome CCD.

  On the other hand, when the color CCD has sufficient resolution and sensitivity, the image sensor 121a may be the color CCD. In this case, the illumination light output unit 130 does not need to irradiate the measurement target S with the red wavelength light, the green wavelength light, and the blue wavelength light in a time division manner, and irradiates the measurement target S with the white light. Therefore, the configuration of the illumination light source 320 can be simplified.

  An A / D converter (analog / digital converter) and a FIFO (First In First Out) memory (not shown) are mounted on the control board 150. The light reception signal output from the camera 121 is sampled at a constant sampling period by the A / D converter of the control board 150 and converted into a digital signal under the control of the control unit 300. The digital signals output from the A / D converter are sequentially stored in the FIFO memory. The digital signals stored in the FIFO memory are sequentially transferred to the PC 200 as pixel data. Here, when the camera 121 is, for example, a monochrome CMOS camera and each pixel of the image sensor 121a outputs a digital electric signal corresponding to the amount of received light to the control board 150, the A / D converter is not always necessary. is not.

  As shown in FIG. 1, the PC 200 includes a CPU (central processing unit) 210, a ROM (read only memory) 220, a work memory 230, a storage device 240, and an operation unit 250. The operation unit 250 also includes a keyboard and a pointing device. A mouse, a joystick, or the like is used as the pointing device.

  A system program is stored in the ROM 220. The work memory 230 is composed of a RAM (random access memory) and is used for processing various data. The storage device 240 includes a hard disk or the like. The storage device 240 stores a shape measurement program. Further, the storage device 240 is used to store various data such as pixel data given from the control board 150.

  The CPU 210 generates image data based on the pixel data provided from the control board 150. Further, the CPU 210 uses the work memory 230 to perform various processes on the generated image data and causes the display unit 400 to display an image based on the image data. Further, the CPU 210 gives a drive signal to the stage drive unit 146 described later through the control board 150. The display unit 400 is composed of, for example, an LCD panel or an organic EL (electroluminescence) panel. An image of the measuring object S in real time (hereinafter referred to as a live image) is displayed on the display unit 400 based on image data (hereinafter referred to as live image data) acquired in real time by the camera 121 of the light receiving unit 120. ) Can be displayed.

  The image of the measurement target S irradiated with the measurement light from one light projection unit 110A and the image of the measurement target S irradiated with the measurement light from the other light projection unit 110B are displayed on the display unit 400 so as to be aligned ( It may be displayed in two screens. In addition, the image of the measuring object S irradiated with the measuring light from one light projecting section 110A and the image of the measuring object S irradiated with the measuring light from the other light projecting section 110B are overlapped on the display section 400. Composite display such as display may be performed.

  When two screens are displayed, for example, the measuring object S is alternately irradiated from the light projecting units 110A and 110B at a constant cycle (several Hz), and the measuring object S is projected from the light projecting unit 110A. The image acquired when the measuring light is irradiated and the image acquired when the measuring object S is irradiated with the measuring light from the light projecting unit 110B are separately displayed on the display unit 400. While watching the displayed image, the user receives the amount of light received by the light receiving unit 120 when the measurement light is emitted from the light projecting unit 110A and the light reception of the light receiving unit 120 when the measurement light is emitted from the light projecting unit 110B. The amount can be adjusted individually. The amount of light received by the light receiving unit 120 can be adjusted by changing the brightness of the measurement light emitted from the light projecting units 110A and 110B or the exposure time of the light receiving unit 120.

  Even when the composite display is performed, the user receives the amount of light received by the light receiving unit 120 when the measurement light is emitted from the light projecting unit 110A while looking at the displayed image, as in the case of the two-screen display. Also, it is possible to adjust the amount of light received by the light receiving unit 120 when the measurement light is emitted from the light projecting unit 110B. In this case, in the display unit 400, in addition to the combined display image, the image of the measuring object S irradiated with the measurement light from one light projecting unit 110A and the measurement light from the other light projecting unit 110B are irradiated. The image of the measurement target S may be displayed side by side. Alternatively, the display unit 400 may switch between the two-screen display image and the composite display image. Alternatively, in the display unit 400, an image of the combined display, an image of the measurement target S irradiated with the measurement light from one light projecting unit 110A, and a measurement target irradiated with the measurement light from the other light projection unit 110B. The image of the object S may be switched and displayed.

  As shown in FIG. 2, the stage 140 includes a stage base 141 and a stage plate 142. The stage plate 142 is arranged on the stage base 141. The stage plate 142 has a mounting surface on which the measurement target S is mounted. Here, two directions orthogonal to each other on the mounting surface of the stage plate 142 are defined as an X direction and a Y direction, which are indicated by arrows X and Y, respectively. Moreover, the direction orthogonal to the mounting surface is defined as the Z direction, and is indicated by an arrow Z. Further, a direction rotating about an axis parallel to the Z direction is defined as a θ direction and is indicated by an arrow θ. The stage plate 142 may be provided with a mounting portion (for example, a screw hole) for mounting a clamp, a jig, or the like.

  A substantially cylindrical measurable region MR is set above the mounting surface of the stage plate 142. The measurable region MR is a region that can be irradiated with the measurement light by the light projecting units 110A and 110B and can be imaged by the light receiving unit 120. The size and position of the measurable region MR differ depending on the magnification and focus position of the lens 122 of the camera 121. When a plurality of light receiving units 120 having different magnifications are provided, the measurable region MR differs depending on the light receiving units 120 used.

  The stage 140 is attached to the rotation mechanism 143. The rotation mechanism 143 includes, for example, a stepping motor. The rotation mechanism 143 is driven by the stage operation unit 145 or the stage drive unit 146 of FIG. 1 to rotate the stage 140 in the θ direction about the rotation axis Ax. In this example, the rotation axis Ax extends in the vertical direction. The direction of the rotation axis Ax is not limited to the vertical direction, and may be slightly inclined with respect to the vertical direction. The user can rotate the stage 140 in the θ direction by manually operating the stage operation unit 145. Further, the stage driving unit 146 can rotate the stage 140 in the θ direction relative to the light receiving unit 120 by supplying a current to the rotating mechanism 143 based on the drive signal given from the PC 200 through the control board 150. it can.

  In this embodiment, the stage 140 can be driven by a stepping motor and can be manually operated, but the present invention is not limited to this. The stage 140 may be driven only by a stepping motor, or may be operated only manually. Further, instead of the stepping motor, another driving device such as a servo motor may be used.

  The controller 300 includes a control board 310 and an illumination light source 320. A CPU (not shown) is mounted on the control board 310. The CPU of the control board 310 controls the light projecting section 110, the light receiving section 120, and the control board 150 based on a command from the CPU 210 of the PC 200. The control board 310 and the illumination light source 320 may be mounted on the measurement unit 100. However, the control board 310 and the illumination light source 320 easily generate heat, and the accuracy of the measurement unit 100 may be deteriorated due to the influence of the heat. Therefore, in order to ensure the accuracy of the measurement unit 100, it is preferable that the control board 310 and the illumination light source 320 be provided outside the measurement unit 100.

  The illumination light source 320 includes, for example, three LEDs that emit red light, green light, and blue light. By controlling the brightness of the light emitted from each LED, it is possible to generate light of any color from the illumination light source 320. Light generated from the illumination light source 320 (hereinafter referred to as illumination light) is output from the illumination light output unit 130 of the measurement unit 100 through the light guide member (light guide). The illumination light output unit 130 of FIG. 2 has an annular shape and is arranged above the stage 140 so as to surround the light receiving unit 120. As a result, the illumination light output unit 130 illuminates the measurement target S with illumination light so that no shadow is generated. The illumination light output unit 130 and the illumination light source 320 may be provided as external devices.

  FIG. 3 is a functional block diagram showing functions realized by the CPU 210 of FIG. As shown in FIG. 3, the CPU 210 has a point cloud data generation unit 501, a synthesis unit 502, a measurement unit 503, a rotation control unit 504, an invalid portion setting unit 505, a three-dimensional shape image data generation unit 506, a reference plane setting unit 507, and The reference plane image data generation unit 508 is included.

  The point cloud data generation unit 501 generates point cloud data representing the three-dimensional shape of the measurement target S based on the light reception signal output by the light reception unit 120. The combining unit 502 generates combined point cloud data by combining the plurality of point cloud data generated by the point cloud data generating unit 501. The measurement unit 503 receives designation of a measurement target portion S to be measured, and calculates a measurement value of the designated location based on the combined point cloud data generated by the combining unit 502. The rotation control unit 504 controls the rotation of the stage 140 by controlling the stage driving unit 146. The invalid portion setting unit 505 sets a portion to be invalidated in the synthetic point group data generated by the synthesizing unit 502. The three-dimensional shape image data generation unit 506 generates three-dimensional shape image data representing an image of the measurement target S viewed in an arbitrary direction based on the combined point cloud data generated by the combining unit 502. The reference plane setting unit 507 sets a reference plane that corresponds to a part of the surface of the measurement target represented by the combined point cloud data generated by the combining unit 502 and serves as a reference for measurement. The reference plane image data generation unit 508 represents an image in which the measurement target S is viewed perpendicularly to the reference plane set by the reference plane setting unit 507 based on the combined point cloud data generated by the combining unit 502. Generate reference plane image data. Details of these functions will be described later.

  The point group data generation unit 501, the synthesis unit 502, the measurement unit 503, the rotation control unit 504, the invalid portion setting unit 505, the three-dimensional shape image data generation unit 506, the reference plane setting unit 507, and the reference plane image data generation unit 508 are the CPU 210. Is realized by executing the shape measurement program stored in the ROM 220 or the storage device 240. These functional units may be realized by hardware such as an electronic circuit.

  FIG. 4 is a schematic external perspective view of the measuring unit 100. In FIG. 4, the appearance of the measurement unit 100 is shown by a thick solid line, and some of the constituent elements provided inside the measurement unit 100 are shown by a dotted line. As shown in FIG. 4, the measuring unit 100 includes a pedestal 170. Two light projecting units 110, a light receiving unit 120, an illumination light output unit 130, and a control board 150 are attached to the pedestal 170. In this state, the positional relationship among the two light projecting units 110, the light receiving units 120, and the illumination light output units 130 is fixed by the pedestal 170. The illumination light output section 130 has a substantially cylindrical shape and is arranged so as to surround the light receiving section 120. An illumination light outlet 131 having an elliptical shape is formed at one end of the illumination light output unit 130. Further, the two light projecting units 110 are arranged side by side with the light receiving unit 120 and the illumination light output unit 130 interposed therebetween.

  A head casing 180 that accommodates a part of the two light projecting units 110, the light receiving unit 120, the illumination light output unit 130, and the control board 150 is attached to the pedestal 170. A head unit 190 is configured by the two light projecting units 110, the light receiving unit 120, the illumination light output unit 130, the control board 150, the pedestal 170, and the head casing 180.

  The measurement unit 100 includes an installation unit 161 and a stand unit 162. The installation portion 161 has a flat bottom surface and is formed to extend in one direction with a substantially constant width. The stand portion 162 is connected to one end of the installation portion 161, and is formed to extend upward from one end of the installation portion 161. The stage 140 is rotatably held on the installation unit 161. The pedestal 170 of the head portion 190 is configured to be attachable to and detachable from the upper end of the stand portion 162. The head part 190 and the installation part 161 are fixedly connected by the stand part 162. As a result, the positional relationship between the stage 140, the two light projecting units 110, and the light receiving units 120 is held constant.

  Each light projecting unit 110 is positioned such that the irradiation region IR to which the measurement light is irradiated includes the stage 140 and the space above it. The measurement light is guided obliquely downward from each light projecting unit 110 with respect to the measurement target S. Each light receiving unit 120 is positioned so that the imaging region TR by the camera 121 of FIG. 2 includes the stage 140 and the space above it. In FIG. 4, the irradiation region IR of each light projecting unit 110 is shown by a two-dot chain line, and the imaging region TR of the light receiving unit 120 is shown by a one-dot chain line.

  FIG. 5 is a diagram for explaining the positional relationship between the light receiving unit 120 and the stage 140. FIG. 5 shows the light receiving unit 120 and the stage 140 viewed from the side. As shown in FIG. 5, the optical axis A1 of the light receiving unit 120 is inclined with respect to the rotation axis Ax of the stage 140 and extends obliquely downward toward the measurement target S on the stage 140.

  The light receiving unit 120 has a virtual imaging surface 120a perpendicular to the optical axis A1. The area where the imaging surface 120a is directed becomes the area where the light receiving unit 120 images. In this example, the imaging surface 120a is directed obliquely downward with respect to the measurable region MR. The inclination angle D1 of the imaging surface 120a with respect to the horizontal plane is set to 45 degrees, for example.

  FIG. 6 is a diagram for explaining a specific configuration example of the stage 140. 6A is a schematic plan view of the stage 140, and FIG. 6B is a schematic cross-sectional view of the stage 140. As shown in FIG. 6A, the stage plate 142 of the stage 140 has a substantially circular shape in plan view. The stage plate 142 includes a substantially semicircular fixed portion 401 and a substantially semicircular inclined portion 402.

  As shown in FIG. 6B, the fixing portion 401 is fixed on the stage base 141. The inclined portion 402 is connected to the fixed portion 401 by the shaft member 403. The shaft member 403 extends vertically (horizontally in this example) with respect to the rotation axis Ax of the stage 140. The fixed portion 401 has a flat fixed mounting surface 401a, and the inclined portion 402 has a flat inclined mounting surface 402a. The fixed mounting surface 401a and the inclined mounting surface 402a form a mounting surface 142a.

  The fixed mounting surface 401a is vertical to the rotation axis of the stage 140, and is horizontal in this example. The inclined portion 402 is rotatable about the shaft member 403, and the inclined mounting surface 402a has a horizontal posture (the posture shown in FIG. 6) in which the inclined mounting surface 402a is perpendicular to the rotation axis Ax of the stage 140, and the inclined mounting surface 402a. The tilted posture is switched to be non-perpendicular to the rotation axis Ax of the stage 140.

  A support portion 404 is provided between the inclined portion 402 and the stage base 141. The support portion 404 is rotatably attached to an attachment portion 141a provided on the upper surface of the stage base 141. A plurality of (three in this example) locking portions 402v for locking the support portion 404 are provided on the lower surface of the inclined portion 402. In this example, the locking portion 402v is a recess.

  FIG. 7 is a diagram for explaining the inclination of the inclined portion 402. As shown in FIGS. 7A to 7C, the inclined portion 402 is inclined and the support portion 404 is erected, and the upper end portion of the support portion 404 is positioned at one of the locking portions 402v of the inclined portion 402. Mated. As a result, the inclined portion 402 is maintained in the inclined posture.

  In this example, the three locking portions 402v are provided on the inclined portion 402v, and the inclination angle D2 of the inclined mounting surface 402a with respect to the horizontal plane can be switched to three stages (four stages when the horizontal posture is included). In the example of FIG. 7A, the inclination angle D2 is 45 degrees, in the example of FIG. 7B, the inclination angle D2 is 60 degrees, and in the example of FIG. 7C, the inclination angle D2 is 30 degrees. It is degree. The inclination angle D2 may be adjustable only to one value (for example, 45 degrees), or may be adjustable to any value without steps. Further, a tilt drive unit that drives the tilt unit 402 may be provided, and the tilt drive unit may automatically tilt the tilt unit 402 according to an instruction from the CPU 210.

  Further, in this example, when the inclined portion 402 is inclined, the portion of the inclined mounting surface 402a closer to the fixed portion 401 than the shaft member 403 becomes lower than the upper surface of the fixed portion 401. Therefore, the measuring object S mounted on the inclined mounting surface 402a is locked by the edge portion of the fixed portion 401. As a result, the measuring object S is maintained in the inclined posture.

[2] Measurement of Shape of Object to be Measured (1) Shape Measurement by Triangular Ranging Method In the measuring unit 100, the shape of the object of measurement S is measured by the triangular distance measuring method. FIG. 8 is a diagram for explaining the principle of the triangulation method. As shown in FIG. 8, an angle α between the optical axis A2 of the measurement light and the optical axis A1 of the light receiving unit 120 is set in advance. The angle α is larger than 0 degrees and smaller than 90 degrees.

  When the measurement target S is not mounted on the stage 140, the measurement light emitted from the light projecting unit 110 is reflected by the point O on the mounting surface of the stage 140 and enters the light receiving unit 120. On the other hand, when the measurement target S is placed on the stage 140, the measurement light emitted from the light projecting unit 110 is reflected by the point A on the surface of the measurement target S and enters the light receiving unit 120.

  When the distance between the point O and the point A in the X direction is d, the height h of the point A of the measuring object S with respect to the mounting surface of the stage 140 is given by h = d ÷ tan (α). The CPU 210 of the PC 200 in FIG. 1 measures the distance d between the point O and the point A in the X direction based on the pixel data of the measurement object S provided by the control board 150. Further, the CPU 210 calculates the height h of the point A on the surface of the measuring object S based on the measured distance d. The three-dimensional shape of the measuring object S is measured by calculating the heights of a plurality of points on the surface of the measuring object S.

  In order to irradiate a plurality of points on the surface of the measuring object S with the measuring light, the light projecting unit 110 in FIG. 1 emits the measuring light having various patterns. The pattern of the measurement light is controlled by the pattern generation unit 112 in FIG. Hereinafter, the pattern of the measurement light will be described.

(2) First Pattern of Measuring Light FIG. 9 is a diagram for explaining the first pattern of measuring light. FIG. 9A shows a state in which the measuring object S on the stage 140 is irradiated with the measuring light from the light projecting unit 110. FIG. 9B shows a plan view of the measuring object S irradiated with the measuring light. As shown in FIG. 9A, as the first pattern, measurement light having a linear cross section parallel to the Y direction (hereinafter, referred to as line measurement light) is emitted from the light projecting unit 110. In this case, as shown in FIG. 9B, the portion of the linear measuring light with which the stage 140 is irradiated and the portion of the linear measuring light with which the surface of the measuring object S is irradiated are of the measuring object S. They are offset from each other in the X direction by a distance d which corresponds to the height h of the surface. Therefore, the height h of the measuring object S can be calculated by measuring the distance d.

  When a plurality of portions along the Y direction on the surface of the measuring object S have different heights, the height h of the plurality of portions along the Y direction is measured by measuring the distance d for each portion. Can be calculated.

  Further, the CPU 210 of FIG. 1 measures the distance d at a plurality of portions along the Y direction at one position in the X direction, and then scans a linear measuring light parallel to the Y direction in the X direction, thereby The distance d is measured for a plurality of portions along the Y direction at other positions in the direction. Thereby, the heights h of the plurality of portions of the measuring object S along the Y direction at the plurality of positions in the X direction are calculated. The height h of each point on the surface of the measuring object S can be calculated by scanning the linear measuring light in the X direction in a range wider than the dimension of the measuring object S in the X direction. Thereby, the three-dimensional shape of the measuring object S can be measured.

(3) Second Pattern of Measuring Light FIG. 10 is a diagram for explaining the second pattern of measuring light. As shown in FIG. 10, as the second pattern, measurement light having a linear cross section parallel to the Y direction and a pattern in which the intensity changes sinusoidally in the X direction (hereinafter referred to as sinusoidal measurement light). ) Is emitted from the light projecting unit 110 a plurality of times (four times in this example).

  FIG. 10A shows the sinusoidal measurement light emitted for the first time. The intensity of the sinusoidal measurement light emitted for the first time has an initial phase φ at an arbitrary portion P0 on the surface of the measuring object S. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by emitting the sinusoidal measuring light. The intensity of the received light is measured based on the pixel data of the measuring object S. Let I1 be the intensity of the light reflected by the portion P0 on the surface of the measuring object S.

  FIG. 10B shows the sinusoidal measurement light emitted for the second time. The intensity of the sinusoidal measurement light emitted the second time has a phase (φ + π / 2) at the portion P0 on the surface of the measurement object S. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by emitting the sinusoidal measuring light. The intensity of the received light is measured based on the pixel data of the measuring object S. The intensity of the light reflected by the portion P0 on the surface of the measuring object S is I2.

  FIG. 10C shows the sinusoidal measurement light emitted for the third time. The intensity of the sinusoidal measurement light emitted for the third time has a phase (φ + π) at the portion P0 on the surface of the measuring object S. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by emitting the sinusoidal measuring light. The intensity of the received light is measured based on the pixel data of the measuring object S. The intensity of the light reflected by the portion P0 on the surface of the measuring object S is I3.

  FIG. 10D shows the sinusoidal measurement light emitted for the fourth time. The intensity of the fourth sinusoidal measurement light has a phase (φ + 3π / 2) at the portion P0 on the surface of the measuring object S. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by emitting the sinusoidal measuring light. The intensity of the received light is measured based on the pixel data of the measuring object S. The intensity of the light reflected by the portion P0 on the surface of the measuring object S is I4.

The initial phase φ is given by φ = tan ⁻¹ [(I1-I3) / (I2-I4)]. The height h of an arbitrary portion of the measuring object S is calculated from the initial phase φ. According to this method, the initial phase φ of each portion of the measuring object S can be calculated quickly and easily by measuring the light intensity four times. The initial phase φ can be calculated by emitting measurement light having different phases at least three times and measuring the intensity of the received light. By calculating the height h of each part on the surface of the measuring object S, the three-dimensional shape of the measuring object S can be measured.

(4) Third Pattern of Measuring Light FIG. 11 is a diagram for explaining the third pattern of measuring light. As shown in FIG. 11, as the third pattern, a plurality of measurement light beams (hereinafter, referred to as striped measurement light beams) having a linear cross section parallel to the Y direction and arranged in the X direction are provided from the light projecting unit 110. It is emitted once (16 times in this example). That is, in the striped measurement light, linear bright portions parallel to the Y direction and linear dark portions parallel to the Y direction are periodically arranged in the X direction.

  The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by emitting the first striped measurement light. The intensity of the received light is measured based on the pixel data of the first captured image of the measuring object S. FIG. 11A is a first captured image of the measuring object S corresponding to the first striped measurement light.

  The second striped measurement light has a pattern in which the bright portion and the dark portion are moved by one unit in the X direction from the first striped measurement light. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by the second striped measurement light being emitted. The intensity of the received light is measured based on the pixel data of the second captured image of the measuring object S.

  The third striped measurement light has a pattern in which the bright portion and the dark portion are moved by one unit in the X direction from the second striped measurement light. The light reflected by the surface of the measuring object S is received by the light receiving unit 120 by the third striped measurement light being emitted. The intensity of the received light is measured based on the pixel data of the third captured image of the measuring object S.

  By repeating the same operation, the light intensities corresponding to the 4th to 16th striped measurement lights are measured based on the pixel data of the 4th to 16th captured images of the measurement object S, respectively. The striped measurement light having a period of 16 units in the X direction is emitted 16 times, so that each portion of the surface of the measuring object S is irradiated with the striped measurement light. Note that FIG. 11B is a seventh captured image of the measuring object S corresponding to the seventh striped measurement light. FIG. 11C is a thirteenth captured image of the measurement object S corresponding to the thirteenth striped measurement light.

  FIG. 12 is a diagram showing the relationship between the timing (number) at which an image of a specific portion of the measuring object S is captured and the intensity of the received light. The horizontal axis of FIG. 12 represents the order of images, and the vertical axis represents the intensity of received light. As described above, for each part of the measurement object S, the first to 16th captured images are generated. In addition, the intensity of light corresponding to each pixel of the generated 1st to 16th captured images is measured.

  As shown in FIG. 12, a scatter diagram is obtained by illustrating the light intensity of each pixel of the captured image corresponding to the number of the captured image. By fitting a Gaussian curve, a spline curve, or a parabola to the obtained scatter diagram, the number (number) of the photographed image when the light intensity becomes maximum can be estimated with an accuracy of less than 1. In the example of FIG. 12, it is estimated from the fitted curved line that the light intensity is maximum in the virtual 9.38th captured image between the 9th and 10th. ..

  Moreover, the maximum value of the light intensity can be estimated from the fitted curve. The height h of each portion of the measuring object S can be calculated based on the number of the captured image where the light intensity estimated in each portion of the measuring object S is maximum. According to this method, the three-dimensional shape of the measuring object S is measured based on the intensity of light having a sufficiently high S / N (signal / noise) ratio. Thereby, the accuracy of the shape measurement of the measuring object S can be improved.

  In the shape measurement of the measuring object S using the measuring light having a periodic pattern shape such as the sinusoidal measuring light or the striped measuring light, the relative height of each part of the surface of the measuring object S is measured. (Relative value of height) is measured. This is because it is not possible to identify each of a plurality of straight lines (fringes) parallel to the Y direction that form a pattern, and there is uncertainty corresponding to an integral multiple of one period (2π) of the plurality of straight lines. , Because the absolute phase cannot be obtained. Therefore, a known unwrapping process is performed on the measured height data based on the assumption that the height of one portion of the measuring object S and the height of the portion adjacent to the portion continuously change. May be done.

(5) Fourth Pattern of Measuring Light FIG. 13 is a diagram for explaining the fourth pattern of measuring light. As shown in FIG. 13, as the fourth pattern, a measurement light (hereinafter, referred to as a coded measurement light) having a linear cross section parallel to the Y direction and having a bright portion and a dark portion aligned in the X direction is used. The light is emitted from the light projecting unit 110 a plurality of times (four times in this example). The proportion of the bright portion and the dark portion of the coded measuring light is 50%, respectively.

  In this example, the surface of the measuring object S is divided into a plurality of (16 in the example of FIG. 13) regions in the X direction. Hereinafter, the areas of the measuring object S in the X direction divided into a plurality of areas will be referred to as first to sixteenth areas, respectively.

  FIG. 13A shows the coded measurement light emitted for the first time. The cord-shaped measurement light emitted for the first time has a bright portion with which the first to eighth regions of the measuring object S are irradiated. In addition, the cord-shaped measurement light emitted for the first time has a dark portion that is irradiated to the ninth to sixteenth regions of the measuring object S. As a result, in the coded measurement light emitted for the first time, the bright portion and the dark portion are parallel to the Y direction and aligned in the X direction. Further, the ratio of the bright portion and the dark portion of the code-like measurement light emitted the first time is 50%.

  FIG. 13B shows the coded measurement light emitted for the second time. The coded measurement light emitted for the second time has a bright portion with which the fifth to twelfth regions of the measuring object S are irradiated. In addition, the cord-shaped measurement light emitted for the second time has a dark portion that is applied to the first to fourth and thirteenth to sixteenth regions of the measuring object S. As a result, in the coded measurement light emitted the second time, the bright portion and the dark portion are parallel to the Y direction and aligned in the X direction. Further, the ratio of the bright portion and the dark portion of the cord-shaped measuring light emitted the second time is 50%.

  FIG. 13C shows the coded measurement light emitted for the third time. The coded measurement light emitted for the third time has a bright portion that is irradiated to the first, second, seventh to tenth, fifteenth, and sixteenth regions of the measuring object S. In addition, the coded measurement light emitted for the third time has a dark portion that is irradiated to the third to sixth and first to fourteenth regions of the measuring object S. As a result, in the coded measurement light emitted the third time, the bright portion and the dark portion are parallel to the Y direction and aligned in the X direction. Further, the ratio of the bright portion and the dark portion of the code-like measurement light emitted the third time is 50%.

  FIG. 13D shows the coded measurement light emitted for the fourth time. The cord-shaped measurement light emitted for the fourth time has a bright portion with which the first, fourth, fifth, eighth, ninth, twelfth, thirteenth, and sixteenth areas of the measuring object S are irradiated. .. In addition, the code-shaped measurement light emitted for the fourth time is a dark portion irradiated to the second, third, sixth, seventh, tenth, eleventh, fourteenth, and fifteenth regions of the measuring object S. Have. As a result, in the coded measurement light emitted for the fourth time, the bright portion and the dark portion are parallel to the Y direction and aligned in the X direction. Further, the ratio of the bright portion and the dark portion of the code-like measuring light emitted the fourth time is 50%.

  A logic "1" is assigned to the bright portion of the coded measurement light, and a logic "0" is assigned to the dark portion of the coded measurement light. In addition, the logical arrangement of the first to fourth coded measurement lights with which each region of the measurement object S is irradiated is referred to as a code. In this case, the first region of the measuring object S is irradiated with the coded measuring light of the code “1011”. As a result, the first region of the measuring object S is encoded as the code “1011”.

  The second region of the measuring object S is irradiated with the coded measuring light having the code “1010”. As a result, the second region of the measuring object S is encoded as the code “1010”. The third region of the measuring object S is irradiated with the coded measuring light with the code “1000”. As a result, the third region of the measuring object S is encoded with the code “1000”. Similarly, the sixteenth region of the measuring object S is irradiated with the coded measuring light having the code “0011”. As a result, the 16th region of the measuring object S is encoded with the code “0011”.

  In this way, between the adjacent regions of the measuring object S, the measuring object S is irradiated with the coded measuring light a plurality of times such that any one of the digits of the code is different by “1”. That is, the coded measurement light is applied to the measurement object S a plurality of times such that the bright portion and the dark portion change into a gray code.

  The light reflected by each area on the surface of the measuring object S is received by the light receiving unit 120. By measuring the sign of the received light, the sign changed due to the existence of the measurement object S is obtained for each region of the measurement object S. The distance corresponding to the distance d in FIG. 8 can be calculated by obtaining the difference between the obtained code and the code when the measurement object S does not exist for each region. Here, the absolute value of the distance d is calculated from the characteristic of the measuring method using the coded measuring light that the above code appears only once in the X-axis direction in the image. Thereby, the absolute height (absolute value of height) of the region of the measuring object S is calculated. By calculating the heights of all the regions on the surface of the measuring object S, the three-dimensional shape of the measuring object S can be measured.

In the above description, the surface of the measuring object S is divided into 16 regions in the X direction, and the coded measuring light is emitted from the light projecting unit 110 four times, but the present invention is not limited to this. The surface of the measuring object S may be divided into 2 ^N regions (N is a natural number) in the X direction, and the coded measuring light may be emitted N times from the light projecting unit 110. In the above description, N is set to 4 for ease of understanding. In the shape measuring process described later, N is set to 8, for example. Therefore, the surface of the measuring object S is divided into 256 regions in the X direction.

  In the shape measurement of the measuring object S using the coded measurement light, the minimum resolution is a distance at which the coded measurement light can be separated and identified, that is, a distance corresponding to one pixel. Therefore, when the number of pixels of the visual field of the light receiving unit 120 in the X direction is 1024 pixels, the measurement target S having a height of 10 mm can be measured with a resolution of 10 mm ÷ 1024≈10 μm. Measurement is performed by combining shape measurement using coded measurement light that has low resolution but can calculate absolute value with shape measurement that uses sinusoidal measurement light or striped measurement light that cannot calculate absolute value but has high resolution. The absolute value of the height of the object S can be calculated with higher resolution.

  In particular, in the shape measurement of the measuring object S using the striped measuring light in FIG. 11, the resolution can be set to 1/100 pixel. Note that the resolution of 1/100 pixel is that when the number of pixels of the visual field in the X direction of the light receiving unit 120 is 1024 pixels, the surface of the measuring object S is divided into about 100000 regions in the X direction (that is, N≈). It corresponds to 17). Therefore, the absolute value of the height of the measuring object S can be calculated with a higher resolution by combining the shape measurement using the coded measuring light and the shape measurement using the striped measuring light.

  The method of scanning the measuring object S with the above-mentioned line-shaped measuring light is generally called a light section method. On the other hand, the method of irradiating the measuring object S with the sinusoidal measuring light, the striped measuring light or the code measuring light is classified into the pattern projection method. Further, among the pattern projection methods, the method of irradiating the measurement object S with the sinusoidal measurement light or the striped measurement light is classified into the phase shift method, and the method of irradiating the measurement object S with the code measurement light is a spatial code. Classified as law.

  In the phase shift method, calculation is performed based on the amount of received light reflected from the reference height position when the measurement target S does not exist when the sinusoidal measurement light or the striped measurement light that is a periodic projection pattern is emitted. The height of the measurement target S is obtained from the phase difference between the calculated phase and the phase calculated based on the amount of received light reflected from the surface of the measurement target S when the measurement target S is present. In the phase shift method, individual periodic fringes cannot be distinguished, and there is an uncertainty corresponding to an integral multiple of one fringe period (2π), so that the absolute phase cannot be obtained. However, as compared with the light section method, the number of images to be acquired is small, so that the measurement time is relatively short and the measurement resolution is high.

  On the other hand, in the space code method, the code changed due to the existence of the measurement object S is obtained for each region of the measurement object S. The absolute height of the measurement object S can be obtained by obtaining the difference between the obtained code and the code when the measurement object S does not exist for each region. The spatial code method also has an advantage that it is possible to measure with a relatively small number of images and it is possible to obtain an absolute height. However, the measurement resolution is limited as compared with the phase shift method.

  These projection methods have their respective advantages and disadvantages, but they all have the common point that they use the principle of triangulation. The three-dimensional shape of the measurement target S is represented based on the image data (hereinafter, referred to as pattern image data) of the measurement target S onto which the measurement light of one or a plurality of the plurality of patterns as described above is projected. Point cloud data is generated.

  In the following description, the point cloud data representing the three-dimensional shape of the measuring object S will be referred to as three-dimensional shape data. The three-dimensional shape data includes position data of a plurality of points on the surface of the measuring object S. The position data represents coordinates in the X direction, Y direction, and Z direction, for example. In this case, if the data of an arbitrary point in the three-dimensional shape data is Pn (n is a natural number), Pn can be represented by (Xn, Yn, Zn) using the coordinate value of the device coordinate system, for example. The three-dimensional shape data may be composed of surface information data generated based on the point cloud data, and may include data in other formats such as a polygon mesh. An image representing the three-dimensional shape of the measurement object S (hereinafter referred to as a three-dimensional shape image) can be displayed based on the three-dimensional shape data.

  In the present embodiment, the three-dimensional shape image is an image showing a state in which the three-dimensional shape data is projected on an arbitrary plane in which the two-dimensional coordinate system is defined, and is used for receiving the designation of the measurement location by the user. It is an image. The user can specify the plane on which the three-dimensional shape data is projected as the direction in which the measurement target S is viewed (the position of the light receiving unit 120 with respect to the measurement target S). Thereby, the orientation of the measuring object S represented by the three-dimensional image changes.

  When the position and orientation of the measuring object S with respect to the light projecting unit 110 and the light receiving unit 120 are constant, only a part of the measuring object S is irradiated with the measuring light. Further, only the light reflected by a part of the measuring object S enters the light receiving unit 120. Therefore, it is not possible to obtain solid shape data over a wide range of the surface of the measuring object S. Therefore, by changing the position or orientation of the measuring object S, the measuring object S is imaged from a plurality of different viewpoints, and a plurality of three-dimensional shape data respectively corresponding to the plurality of viewpoints are acquired. By combining the plurality of acquired three-dimensional shape data, combined three-dimensional shape data (composite point group data) is generated.

  FIG. 14 is a diagram for explaining an example of generating a plurality of three-dimensional shape data by imaging the measurement target S from a plurality of viewpoints. For example, as shown in FIG. 14A, after the user adjusts the position and orientation of the measurement target S on the stage 140, the measurement target S is imaged using the measurement light, and thus the first measurement is performed. Three-dimensional shape data is generated. An example of a stereoscopic image based on the first stereoscopic shape data is shown in FIG. The three-dimensional shape data is generated based on the measurement light reflected by the surface of the measurement target S and incident on the light receiving unit 120. Therefore, three-dimensional shape data is generated for the portion of the surface of the measuring object S that faces the light receiving unit 120, but three-dimensional shape data cannot be generated for the portion that does not face the light receiving unit 120. ..

  Then, as shown in FIG. 14B, after the stage 140 is rotated by a certain angle by the rotation mechanism 143 of FIG. 2, the measurement object S is imaged using the measurement light, so that the second three-dimensional shape data is obtained. Is generated. In the example of FIG. 13B, the stage 140 is rotated counterclockwise by a predetermined angle from the state of FIG. 14A. An example of a stereoscopic image based on the second stereoscopic shape data is shown in FIG. As described above, when the stage 140 rotates, the portion of the surface of the measuring object S facing the light receiving unit 120 changes with the rotation. As a result, three-dimensional shape data including a part that was not acquired at the time of the first imaging is generated.

  Further, as shown in FIG. 14C, after the stage 140 is rotated by a certain angle by the rotation mechanism 143 of FIG. 2, the measurement object S is imaged using the measurement light, so that the third three-dimensional shape data is obtained. Is generated. In the example of FIG. 14C, the stage 140 is rotated counterclockwise by a predetermined angle from the state of FIG. 14B. An example of a three-dimensional image based on the third three-dimensional data is shown in FIG.

  In this way, the rotation of the stage 140 and the imaging of the measurement target S are repeated, so that a plurality of three-dimensional shape data corresponding to a plurality of viewpoints is generated. The one rotation angle of the stage 140 and the number of rotations thereof may be predetermined or may be arbitrarily designated by the user. By synthesizing these three-dimensional shape data, synthetic three-dimensional shape data representing a wide range of three-dimensional shapes of the measuring object S is generated.

  In the present embodiment, the relative positions of the light receiving unit 120, the light projecting unit 110, and the stage 140 are constant, and parameters (hereinafter, device parameters) representing these relative positions are stored in advance in, for example, the storage device 240 in FIG. To be done. When the stage drive unit 146 of FIG. 1 drives the rotation mechanism 143, for example, the rotation angle of the stage 140 is designated in advance by the user, and the stage drive unit 146 is controlled based on the stored angle. In this case, the rotation angle of the stage 140 is stored in, for example, the ROM 220 or the work memory 230 of FIG. When synthesizing a plurality of three-dimensional shape data, the CPU 210 of FIG. 1 can easily and accurately align the plurality of three-dimensional shape data based on the stored rotation angle and the device parameter. Further, the user may perform detailed setting and correction of alignment.

  A sensor or the like that detects the rotation angle of the stage 140 may be provided. In this case, even when the user operates the stage operation unit 145 to rotate the stage 140, it is easy to align a plurality of three-dimensional shape data based on the angle detected by the sensor and the above-mentioned device parameter. It can be done accurately and accurately.

[3] Texture Image In the measurement unit 100, the illumination light output unit 130 irradiates the measurement object S with illumination light, or the light projecting units 110A and 110B illuminate the measurement object S with uniform measurement light. In this state, image data (hereinafter referred to as texture image data) representing the appearance (surface state) of the measuring object S is generated. The uniform measuring light is a measuring light having no pattern and can be used instead of the illuminating light. The surface state of the measuring object S includes, for example, a pattern or a color. Hereinafter, the image represented by the texture image data is referred to as a texture image.

  Various examples of texture image data will be described. For example, a plurality of texture image data are acquired while the focus position of the light receiving unit 120 is relatively changed with respect to the measurement target S. By combining the plurality of texture image data, texture image data in which the entire surface of the measuring object S is in focus (hereinafter, referred to as omnifocal texture image data) is generated.

  Further, a plurality of texture image data may be acquired under a plurality of different imaging conditions. The imaging conditions include, for example, the exposure time of the light receiving unit 120, the intensity (brightness) of the illumination light from the illumination light output unit 130, the uniform intensity (brightness) of the measurement light from the light projecting unit 110, and the like. Well-known high dynamic (HDR) composition is performed using a plurality of acquired texture image data. As a result, texture image data (hereinafter referred to as HDR texture image data) in which blackout and whiteout due to differences in brightness are suppressed is generated.

  Further, the imaging condition may be changed as the focus position is changed. Specifically, the focus position of the light receiving unit 120 is relatively changed with respect to the measurement target S, and the texture image data is acquired under a plurality of different imaging conditions at each focus position. By synthesizing a plurality of acquired texture image data, it is possible to generate texture image data in which the entire surface of the measurement target S is focused and blackout and whiteout are suppressed.

  Each texture image data includes texture information (information indicating an optical surface state) indicating the color or brightness of each point on the measurement target S. On the other hand, the synthetic three-dimensional shape data does not include the texture information of the measuring object S. Therefore, the synthesized three-dimensional shape data and any one of the texture image data are synthesized to generate textured three-dimensional shape data in which texture information is added to the synthesized three-dimensional shape data.

  The textured three-dimensional shape data includes position data of a plurality of points on the surface of the measuring object S and data indicating the color or brightness of the point associated with the position data of each point. In this case, if the data of an arbitrary point in the textured three-dimensional shape data is TPn (n is a natural number), TPn is, for example, the coordinate value of the device coordinate system and the three primary color components (R, G) of red, green, and blue. , B) and can be represented by (Xn, Yn, Zn, Rn, Gn, Bn). Alternatively, TPn can be represented by (Xn, Yn, Zn, In) using, for example, the coordinate value of the device coordinate system and the brightness value (I). The textured solid shape data may be composed of surface information data generated based on the point cloud data.

  In the following description, the texture image represented by the texture image data acquired in a fixed focus position and imaging conditions is called a normal texture image, the image represented by the omnifocal texture image data is called an omnifocal texture image, An image represented by HDR texture image data is called an HDR texture image. An image represented by textured solid shape data is called a textured solid shape image.

[4] Shape Measurement Processing (1) Preparation for Shape Measurement Before executing the shape measurement processing for the measurement object S, the user prepares for shape measurement. FIG. 15 is a flowchart showing the procedure for preparation for shape measurement. Hereinafter, the procedure for preparation for shape measurement will be described with reference to FIGS. 1, 2, and 15. First, the user places the measuring object S on the stage 140 (step S1). Next, the user irradiates the measuring object S with the measuring light from the light projecting unit 110 (step S2). Subsequently, the user adjusts the brightness of the acquired live image and the position and orientation of the measurement target S while observing the live image displayed on the display unit 400 (hereinafter referred to as the first adjustment). Is performed (step S3). The brightness of the live image acquired in step S3 can be adjusted by changing at least one of the light amount of the measurement light and the exposure time of the light receiving unit 120. In the present embodiment, in order to make the brightness of the live image acquired using the measurement light suitable for observation, one of the light amount of the measurement light and the exposure time of the light receiving unit 120 is adjusted. In addition, it is preferable that the brightness of the acquired live image is adjusted by the exposure time of the light receiving unit 120 while keeping the light amount of the measurement light constant. This suppresses a decrease in measurement accuracy due to a change in the temperature of the measurement light source 111 with a change in the amount of measurement light.

  In step S2, the measurement object S may be irradiated with any of the above-described first to fourth patterns of measurement light, or the measurement object S may be irradiated with uniform measurement light. In step S3, when a shadow of the measurement target S to be measured (hereinafter referred to as a measurement position) does not occur, the user does not need to adjust the position and orientation of the measurement target S. Instead, the light amount of the measurement light or the exposure time of the light receiving unit 120 may be adjusted.

  Next, the user stops the irradiation of the measurement light and irradiates the measurement object S with the illumination light from the illumination light output unit 130 (step S4). Subsequently, the user adjusts the brightness of the acquired live image (hereinafter referred to as the second adjustment) while watching the live image displayed on the display unit 400 (step S5). The brightness of the live image acquired in step S5 can be adjusted basically by changing at least one of the light amount of the illumination light and the exposure time of the light receiving unit 120, as in the example of step S3. In the present embodiment, either the light amount of the illumination light or the exposure time of the light receiving unit 120 is adjusted in order to make the brightness of the live image acquired by using the illumination light suitable for observation.

  Next, the user confirms the live image displayed on the display unit 400, and determines whether the light amount, the exposure time of the light receiving unit 120, and the position and orientation of the measurement target S (hereinafter, referred to as an observation state) are appropriate. It is determined whether or not (step S6). In step S6, the measurement object S may be irradiated with the measurement light, the irradiation light, or the measurement light and the illumination light may be sequentially irradiated.

  When it is determined in step S6 that the observation state is not appropriate, the user returns to the process of step S2. On the other hand, when it is determined in step S6 that the observation state is appropriate, the user ends preparation for shape measurement.

  In the above description, the second adjustment is performed after the first adjustment, but the present invention is not limited to this. The first adjustment may be performed after the second adjustment. In this case, the user adjusts the position and orientation of the measuring object S in the second adjustment, and confirms that the desired portion of the measuring object S is irradiated with the measurement light in the first adjustment. Good. When the measurement light is not applied to the desired portion of the measurement object S, the position and the posture of the measurement object S are readjusted, and the light amount of the illumination light or the exposure time of the light receiving unit 120 is again adjusted as the second adjustment. May be adjusted.

(2) First Adjustment FIGS. 16 and 17 are flowcharts showing the details of the first adjustment in the procedure for the preparation of the shape measurement. Hereinafter, the details of the first adjustment in the procedure for the shape measurement preparation will be described with reference to FIGS. 1, 2, 16, and 17. Hereinafter, the measurement light emitted from one of the light projecting units 110A and 110B will be referred to as one measurement light, and the measurement light emitted from the other will be referred to as the other measurement light. Here, in the measurement unit 100 according to the present embodiment, the light amounts of the one and the other measurement lights can be independently set. Further, the exposure time of the light receiving unit 120 when the measurement target S is imaged using one measurement light and the exposure time of the light reception unit 120 when the measurement target S is imaged using the other measurement light are Each can be set independently.

  First, the user tentatively adjusts the light amount of one measurement light or the exposure time of the light receiving unit 120 in order to make the brightness of the acquired live image suitable for observation (step S11). Next, the user adjusts the magnification of the live image of the measurement object S displayed on the display unit 400 (hereinafter referred to as the field size) (step S12). Specifically, when a plurality of light receiving units 120 having different magnifications are used, the user selects any one of the light receiving units 120. Thereby, the live image acquired by the selected light receiving unit 120 is displayed on the display unit 400. The visual field size when the low-magnification light receiving unit 120 is selected is larger than the visual field size when the high-magnification light receiving unit 120 is selected. The measuring unit 100 may have a digital zoom function. In this case, the user can adjust the display magnification of the live image acquired by the light receiving unit 120.

  Subsequently, the user determines whether or not the position and orientation of the measuring object S is appropriate based on the live image displayed on the display unit 400 (step S13). Here, when the shadow is not generated at the measurement location of the measurement target S, the user determines that the position and orientation of the measurement target S are appropriate. On the other hand, when a shadow is generated at the measurement location of the measurement object S, the user determines that the position and orientation of the measurement object S are not appropriate.

  When it is determined in step S13 that the position and orientation of the measuring object S are not appropriate, the user adjusts the position and orientation of the measuring object S (step S14). Specifically, the user adjusts the position and orientation of the measuring object S by rotating the stage 140 with the rotating mechanism 143 or moving the measuring object S by hand. After that, the user returns to the process of step S13.

  On the other hand, when it is determined in step S13 that the position and orientation of the measuring object S are appropriate, the user observes the brightness of the acquired live image based on the live image displayed on the display unit 400. It is determined whether or not the brightness is suitable for the measurement target S, that is, whether or not the light amount of one of the measurement lights applied to the measurement target S or the exposure time of the light receiving unit 120 is appropriate (step S15).

  When it is determined in step S15 that the light amount of one measurement light or the exposure time of the light receiving unit 120 is not appropriate, the user adjusts the light amount of one measurement light or the exposure time of the light receiving unit 120 (step S16). Then, the user returns to the process of step S15.

  On the other hand, if it is determined in step S15 that the light amount of one of the measurement lights or the exposure time of the light receiving unit 120 is appropriate, the user determines whether the observation state is appropriate from the live image displayed on the display unit 400. It is determined whether or not (step S17). When it is determined in step S17 that the observation state is not appropriate, the user returns to the process of step S14 or step S16. Specifically, when it is determined that the position and orientation of the measuring object S is not appropriate in the observation state, the user returns to the process of step S14. When it is determined that the light amount of the light (one measurement light) or the exposure time of the light receiving unit 120 is not appropriate in the observation state, the user returns to the process of step S16.

  On the other hand, when it is determined in step S17 that the observation state is appropriate, the user stops the irradiation of one measurement light and irradiates the measurement target S with the measurement light from the other light projecting unit 110B ( Step S18 of FIG. 17). Subsequently, while viewing the live image displayed on the display unit 400, the user sets the light amount of the other measurement light or the light receiving unit 120 in order to make the brightness of the obtained live image suitable for observation. The exposure time is adjusted (step S19).

  Then, based on the live image displayed on the display unit 400, the user determines whether or not the brightness of the acquired live image is suitable for observation, that is, the light amount of the other measurement light or the light receiving unit. It is determined whether the exposure time of 120 is appropriate (step S20). When it is determined in step S20 that the light amount of the other measurement light or the exposure time of the light receiving unit 120 is not appropriate, the user returns to the process of step S19. On the other hand, in step S20, when it is determined that the light amount of the other measurement light or the exposure time of the light receiving unit 120 is appropriate, the user ends the first adjustment. By performing the first adjustment, the optimum light amount condition of the one and the other measurement light for generating the three-dimensional shape data, or the exposure time condition of the light receiving unit 120 corresponding to the one and the other measurement light, respectively, can be obtained. Is set. Note that when the other light projecting unit 110B is not used, the user may omit the procedure of steps S18 to S20 and end the first adjustment after the process of step S17.

(3) Second Adjustment FIG. 18 is a flowchart showing details of the second adjustment in the procedure for the preparation for shape measurement. Hereinafter, the details of the second adjustment in the procedure for the shape measurement preparation will be described with reference to FIGS. 1, 2, and 18. Here, in measurement unit 100 according to the present embodiment, the light amount of the illumination light can be set independently of the light amounts of the one and the other measurement lights. Further, the exposure time of the light receiving unit 120 when the measurement object S is imaged using the illumination light is independent of the exposure time of the light receiving unit 120 when the measurement object S is imaged using one or the other measurement light. Can be set.

  First, the user adjusts the light amount of the illumination light or the exposure time of the light receiving unit 120 in order to make the brightness of the acquired live image suitable for observation (step S31). Next, based on the live image displayed on the display unit 400, the user determines whether or not the brightness of the acquired live image is suitable for observation, that is, the measurement target S is illuminated. It is determined whether the amount of illumination light or the exposure time of the light receiving unit 120 is appropriate (step S32).

  When it is determined in step S32 that the amount of illumination light or the exposure time of the light receiving unit 120 is not appropriate, the user returns to the process of step S31. On the other hand, when it is determined in step S32 that the amount of illumination light or the exposure time of the light receiving unit 120 is appropriate, the user selects the type of texture image to be displayed (step S33) and makes the second adjustment. finish. The types of texture images include, for example, normal texture images, omnifocal texture images, and HDR texture images. By performing the second adjustment, the optimum light amount condition of the illumination light for generating the texture image data or the condition of the exposure time of the light receiving unit 120 corresponding to the illumination light is set.

  Further, when the omnifocal texture image or the HDR texture image is selected in step S33, the setting for appropriately acquiring the omnifocal texture image data or the HDR texture image data may be separately performed. For example, when the omnifocal texture image is selected, the change range of the focus position may be set. Further, when the HDR texture image data is selected, the details of the imaging condition and the like may be set. Further, an omnifocal texture image for preview or an HDR texture image may be displayed on the display unit 400 based on these settings.

(4) Shape Measurement Processing After the preparation for the shape measurement of FIGS. 15 to 18, the shape measurement processing of the measuring object S is executed. FIG. 19 is a flowchart showing an outline of the shape measuring process. When the user instructs the CPU 210 to start the shape measuring process, the CPU 210 irradiates the measuring object S with the measuring light according to the light amount condition or the exposure time condition set in the first adjustment. The image data (pattern image data) of the measurement target S on which the pattern of the measurement light is projected is acquired (step S41). The acquired pattern image data is stored in the work memory 230.

  Next, the CPU 210 processes the acquired pattern image data by a predetermined measurement algorithm to generate three-dimensional shape data indicating the three-dimensional shape of the measuring object S (step S42). The generated solid shape data is stored in the work memory 230.

  Next, the CPU 210 acquires texture image data corresponding to the type of texture image selected in step S33 of FIG. 18 (step S43). The acquired texture image data is stored in the work memory 230.

  Next, the CPU 210 determines whether or not all the images of the measurement target S have been captured, based on the preset generation conditions (step S44). When all the imaging is not completed, the CPU 210 rotates the stage 140 (FIG. 2) by a predetermined angle based on the generation condition (step S45), and returns to the process of step S41.

  When all the imaging is completed in step S44, the CPU 210 synthesizes a plurality of solid shape data generated by repeating the processing of step S42 a plurality to generate synthetic solid shape data (step S46). Next, the CPU 210 synthesizes the plurality of texture image data generated by repeating the process of step S43 with the synthesized three-dimensional shape data to generate textured three-dimensional shape data (step S47). If the processes of steps S41 to S45 have been executed only once, the process of step S46 is omitted.

  Next, the CPU 210 causes the display section 400 to display the stereoscopic image of the measurement object S or the stereoscopic image with texture based on the generated synthetic stereoscopic shape data or textured stereoscopic shape data (step S48). In this case, the user can appropriately select the image to be displayed. In step S48, when the measurement location of the measurement object S is not properly displayed, the user may perform the first and second adjustments of FIGS. 16 to 18 again. After that, the CPU 210 executes the measurement of the measurement location based on the measurement condition set by the user (step S49). The setting of measurement conditions will be described later. This completes the shape measurement process.

[5] Switching of Stage FIG. 20 is an external perspective view showing an example of the measuring object S. 20A shows the measurement target S viewed from diagonally above, and FIG. 20B shows the measurement target S viewed from diagonally below. As shown in FIG. 20A, the measurement object S includes a flat plate-shaped substrate B1 and a substantially rectangular parallelepiped element B2. The element B2 is mounted on the upper surface of the substrate B1. Further, as shown in FIG. 20B, a pair of concave portions B1a having a circular cross section are provided at a pair of corners on the lower surface of the substrate B1.

  21 and 22 are diagrams showing a state in which the measurement target S of FIG. 20 is placed on the stage 140. In the example of FIG. 21, the inclined portion 402 is in a horizontal posture, and the measurement target S is mounted on the mounting surface 142a perpendicular to the rotation axis Ax. In the following description, the state in which the inclined portion 402 of the stage 140 is in the horizontal posture is called the standard state, and the state in which the inclined portion 402 is in the inclined posture is called the inclined state.

  In the example of FIG. 21A, the upper surface of the substrate B1 faces upward. In this case, by rotating the stage 140, the upper surface of the substrate B1 and the element B2 can be imaged by the light receiving unit 120. On the other hand, even if the stage 140 is rotated, the lower surface of the substrate B1 cannot be imaged by the light receiving unit 120. Therefore, it is not possible to generate the three-dimensional shape data of the lower surface of the substrate B1.

  Further, in the example of FIG. 21B, the lower surface of the substrate B1 is directed upward. In this case, the lower surface of the substrate B1 can be imaged by the light receiving unit 120 by rotating the stage 140. On the other hand, even if the stage 140 is rotated, the upper surface of the substrate B1 and the element B2 cannot be imaged by the light receiving unit 120. Therefore, the three-dimensional shape data of the upper surface of the substrate B1 and the element B2 cannot be generated.

  As described above, in the standard state, when the posture of the measurement target S is constant, it is not possible to generate part of the three-dimensional shape data of the measurement target S. When there is a measurement point in such a portion, the user needs to change the posture of the measurement target S on the stage 140 and generate three-dimensional shape data for each posture of the measurement target S.

  To measure both the dimension of the element B2 and the diameter of the recess B1a of the substrate B1 in the measurement object S of FIG. 20, for example, as in the example of FIG. 21. The measurement object S is placed so that the three-dimensional shape data is generated once, and the measurement object S is placed so that the lower surface of the substrate B1 faces upward as in the example of FIG. It is necessary to generate the three-dimensional shape data again after placing it. In addition, in order to generate synthetic three-dimensional shape data from these three-dimensional shape data, the user needs to perform alignment of the three-dimensional shape data. Therefore, the working time becomes long and the burden on the user becomes heavy.

  On the other hand, in the tilted state, a wider part of the measurement target S can be imaged without changing the posture of the measurement target S. In the example of FIGS. 22A and 22B, the inclination angle D2 of the inclined portion 402 is set to be larger than the inclination angle D1 of the imaging surface 120a of the light receiving unit 120, and the inclination angle D2 is 60 degrees, for example. Is set to. The measurement object S is placed on the inclined portion 402 such that the lower surface of the substrate B1 overlaps the inclined mounting surface 402a of the inclined portion 402. A part of the substrate B1 is located outside the outer periphery of the inclined portion 402, and the lower surface portion of the substrate B1 including the pair of concave portions B1a is exposed without overlapping the inclined portion 402.

  As shown in FIG. 22A, the substrate of the measuring object S is in a state where the inclined portion 402 is located farther from the light receiving portion 120 than the fixed portion 401 and the inclined mounting surface 402 a is directed to the light receiving portion 120. The upper surface of B1 and the element B2 are imaged by the light receiving unit 120. Thereby, three-dimensional shape data including the upper surface of the substrate B1 and the element B2 can be generated.

  On the other hand, as shown in FIG. 22B, when the inclined portion 402 is located closer to the light receiving portion 120 than the fixed portion 401 and the inclined mounting surface 402a is directed to the opposite side of the light receiving portion 120, the substrate The exposed portion of the lower surface of B1 is directed to the light receiving unit 120. Thereby, a part of the lower surface of the substrate B1 can be imaged by the light receiving unit 120. Therefore, a part of the three-dimensional shape data of the lower surface of the substrate B1 can be generated.

  As described above, when the posture of the measuring object S is constant, three-dimensional shape data of the portion of the measuring object S, which cannot be generated in the standard state, can be generated in the inclined state. Therefore, in the inclined state, it is possible to generate synthetic three-dimensional shape data of a wider portion of the measuring object S without imposing a burden on the user.

  The display of an image based on the composite stereoscopic shape data will be described. In the following description, the three-dimensional image and the three-dimensional image with texture are collectively referred to as an object image. FIG. 23 is a diagram showing an example of an object image based on the combined three-dimensional shape data generated in the inclined state. As shown in FIG. 23, the synthetic three-dimensional shape data includes position data of the measuring object S imaged by the light receiving unit 120 and its peripheral portion. Hereinafter, the measurement target S imaged by the light receiving unit 120 and its peripheral portion are referred to as an imaged object.

  The object image GT in FIG. 23 includes the measurement object S and the stage plate 142 as the imaged objects. Normally, when performing measurement on the measurement target S, it is not necessary to display a portion around the measurement target S. Therefore, in this embodiment, unnecessary portions can be removed from the object image GT. Specifically, it is possible to set an invalid portion (hereinafter referred to as an invalid portion) in the synthetic solid shape data. In that case, the object image data is generated without using the invalid portion of the synthetic stereoscopic shape data.

  FIG. 24 is a diagram for describing an example of setting an invalid part. The user can arbitrarily change the orientation of the imaged object in the object image GT. Specifically, when the user instructs to change the orientation of the imaged object, the object image data is updated based on the composite stereoscopic shape data, and the orientation of the imaged object is changed based on the updated object image data. The object image GT in the cut state is displayed.

  The side surface of the measuring object S and the stage plate 142 is shown in the object image GT of FIG. In this state, the user designates an invalid area on the object image GT with a pointer or the like. In the example of FIG. 24A, the portion outside the outer edge of the measuring object S is set as the invalid portion. As a result, as shown in FIG. 24B, the part other than the measurement target S can be removed from the target image GT.

  FIG. 25 is a diagram showing an example of the object image GT from which unnecessary portions have been removed. As shown in FIG. 25, since the object image GT does not include the stage plate 142, the overall three-dimensional shape of the measurement object S can be more easily recognized. In addition, since the invalid portion of the synthetic three-dimensional shape data is not used at the time of measurement described later, it is possible to prevent incorrect measurement values from being calculated.

  Note that position data that is a candidate for an invalid portion may be stored in advance in, for example, the storage device 240 in FIG. 1, and the invalid portion may be set according to a user's instruction. For example, position data of the surface of the stage plate 142 when the inclined portion 402 is in the horizontal posture is stored as first invalid data, and position data of the surface of the stage plate 142 when the inclined portion 402 is in the inclined posture is stored. , As the second invalid data. When the synthetic stereoscopic shape data is generated in the standard state, the stage plate 142 can be removed from the object image GT by setting the invalid portion based on the first invalid data. Further, when the synthetic three-dimensional shape data is generated in the inclined state, the stage plate 142 can be removed from the object image GT by setting the invalid portion based on the second invalid data. In this way, it is not necessary to specify an invalid portion each time the synthetic stereoscopic shape data is generated, and unnecessary portions can be easily removed from the object image GT based on the position data stored in advance.

[6] Acquisition of Measurement Value In step S50 of FIG. 19, the user sets measurement conditions while viewing the target object image GT displayed on the display unit 400. The measurement conditions include measurement items and measurement points. The measurement item is the type of parameter to be measured, and includes distance, height, diameter, area, and the like. In addition, a geometric shape (for example, a point, a straight line, a circle, a surface, a sphere, a cylinder, a cone, or the like) for specifying a measurement location may be designated as the measurement item.

  The setting of measurement conditions will be described. First, a reference plane that is a reference for measurement is set. FIG. 26 is a flowchart showing an operation example of the CPU 210 when setting the reference plane.

  The user specifies the surface of the measuring object S to be the reference surface on the displayed object image GT. For example, a pointer is displayed on the display unit 400 together with the object image GT. The user operates the operation unit 250 to move the pointer and designates the target surface with the pointer. The CPU 210 determines whether or not the surface to be the reference surface is designated (step S61). When the surface is not designated, the CPU 210 repeats the process of step S61.

  Next, the CPU 210 extracts the plane closest to the designated surface based on the composite stereoscopic shape data (step S62), and sets the extracted plane as the reference plane (step S63). Usually, each surface of the measuring object S is not a perfect flat surface because it slightly includes irregularities or is slightly curved. Therefore, a virtual plane having the highest degree of coincidence with the designated plane is extracted and set as the reference plane. Next, the CPU 210 generates reference plane image data based on the set reference plane, and displays the reference plane image on the display unit 400 using the generated reference plane image data (step S64). The reference plane image is a two-dimensional (plan view) image in which the measurement target S is viewed perpendicularly to the reference plane. That is, in the reference plane image, the set reference plane is parallel to the screen of the display unit 400.

  FIG. 27 is a diagram showing an example of the reference plane image. In the reference plane image GS of FIG. 27, the lower surface of the substrate B1 is designated and set as the reference plane. Therefore, the upper surface of the element B2 is substantially parallel to the screen of the display section 400. FIG. 28 is a diagram for explaining an example of setting measurement conditions. In the example of FIG. 28A, the diameter is specified as the measurement item, and one concave portion B1a is specified as the measurement point. In this case, the measurement point is set on the reference plane. When the measurement item and the measurement point are designated, the measurement value corresponding to the designated measurement item and the measurement point is calculated based on the synthetic three-dimensional shape data, and is displayed on the reference plane image GS. In the example of FIG. 28B, “xx (mm)” is displayed as the diameter of the recess B1a on the reference surface image GS.

  In the example of FIG. 28, the measurement condition is set using the reference plane image GS, but the measurement condition may be set using the object image GT. For example, the distance between the two surfaces is specified as the measurement item. Further, on the object image GT, two surfaces of the measurement object S are designated as measurement points. In this case, the distance between the two designated surfaces is calculated as a measurement value and displayed on the object image GT. When the measurement condition is set using the object image GT, the reference plane does not have to be set.

  FIG. 29 is a diagram showing another example of the reference surface image GS. In the reference plane image GS of FIG. 29, the reference plane is set so as to correspond to the upper surface of the substrate B1. In the example of FIG. 29, each part of the measuring object S is given a color corresponding to the difference in height with respect to the reference plane. Here, the height means a distance from the reference plane in a direction perpendicular to the reference plane. In FIG. 29, the difference in color is represented by the difference in dot pattern. In this case, the user can easily recognize the difference in height between the reference surface and other portions. The reference plane image functions as a height image in which the three-dimensional shape data or the three-dimensional shape data with texture is represented by the height from a predetermined reference plane.

  An image (hereinafter, referred to as a profile image) representing the profile (cross-sectional shape) of the measurement object S may be displayed based on the combined three-dimensional shape data. FIG. 30 is a diagram for explaining the designation of the portion where the profile should be acquired, and FIG. 31 is a diagram showing an example of the profile image.

  In the example of FIG. 30, on the reference surface image GS, the line segment LS specifies the location of the measurement object S whose profile is to be acquired. In this case, profile data representing the profile of the measuring object S on the plane that passes through the line segment LS and is perpendicular to the reference plane is generated based on the synthetic solid shape data. The profile image GP of FIG. 31 is displayed based on the generated profile data. The profile image GP includes a profile line PL representing the profile of the measuring object S.

  The measurement condition may be set using the profile image GP. In the example of FIG. 30, the distance between the two surfaces is designated as the measurement item, and the line segment L11 and the line segment L12 on the profile line PL are designated as the measurement points. The line segments L11 and L12 correspond to the upper surface of the substrate B1 and the upper surface of the element B2 of the measuring object S, respectively. In this case, the distance between the line segment L11 and the line segment L12 (the distance between the upper surface of the substrate B1 and the upper surface of the element B3) is calculated as a measurement value based on the synthetic solid shape data or the profile data. The calculated measurement value "yy" is displayed on the profile image GP.

[7] Face-to-face state Even if the tilt angle of the tilt portion 402 and the rotational position of the stage 140 are adjusted so that the image pickup surface 120a (FIG. 5) of the light receiving unit 120 and the tilt mounting surface 402a of the stage 140 face each other. Good. Hereinafter, a state in which the image pickup surface 120a of the light receiving unit 120 and the inclined mounting surface 402a of the stage 140 face each other is referred to as a facing state. The fact that the imaging surface 120a and the inclined mounting surface 402a face each other is not limited to the case where the inclined mounting surface 402a and the imaging surface 120a are parallel to each other, and the inclined mounting surface 402a and the imaging surface 120a are constant. It also includes the case of forming an angle within the range (for example, 10 degrees or less).

  FIG. 32 is a diagram showing the relationship between the light receiving unit 120, the stage 140, and the measurement target S in the facing state. In the example of FIG. 32, the inclination angle D1 of the imaging surface 120a of the light receiving unit 120 and the inclination angle D2 of the inclination portion 402 of the stage 140 are equal to each other, and the imaging surface 120a and the inclination mounting surface 402a are parallel to each other.

  Since the inclined portion 402 is provided integrally with the stage base 141, the rotational position of the stage 140 in the facing state is constant. The CPU 210 of FIG. 1 can adjust the rotational position of the stage 140 based on a user's instruction so that the stage 140 is in a facing state.

  As shown in FIG. 32, a portion of the measuring object S that is directed vertically upward in the standard state (hereinafter referred to as an upper surface region) is directed to the light receiving unit 120 in the facing state. Therefore, in the facing state, the three-dimensional shape data of the upper surface region is generated.

  When the measurement point is in the upper surface region, it is possible to measure the measurement point using only the three-dimensional shape data generated in the facing state without combining the plurality of three-dimensional shape data. As a result, unnecessary three-dimensional shape data is not generated, so that it is possible to quickly measure the measurement location.

  Further, the object image GT representing the upper surface region can be displayed using the three-dimensional shape data generated in the facing state. When the surface of the measurement target S included in the upper surface region (for example, the upper surface of the substrate B1) is designated as the reference surface, the user can easily designate the reference surface on the target object image GT. Therefore, the user can efficiently and quickly set the reference plane and the measurement conditions.

[8] Effects Since the light emitting unit 110, the light receiving unit 120, and the stage 140 are integrally provided in the measuring device 500 according to the present embodiment, the user does not need to adjust their arrangement. By mounting the measuring object S on the stage 140, the three-dimensional shape data of the measuring object S can be obtained. Further, since the measuring object S is mounted on the inclined mounting surface 402a that is non-perpendicular to the rotation axis Ax of the stage 140, it is possible to maintain the measuring object S in an inclined posture without using a jig or the like. It is possible to easily acquire the point cloud data of a necessary place.

  In addition, since the rotation axis Ax of the stage 140 is not parallel to the optical axis A1 of the light receiving unit 120, rotating the stage 140 changes the location of the measurement target S directed toward the light receiving unit 120. Therefore, the light receiving unit 120 images different portions of the measurement target S. Therefore, it is possible to generate three-dimensional shape data of different positions of the measurement object. Furthermore, synthetic solid shape data is generated by synthesizing the generated plurality of point group data. The synthetic three-dimensional shape data includes three-dimensional shapes of various points of the measurement target represented by the plurality of three-dimensional shape data. Therefore, it is possible to easily calculate the measurement value of a desired portion of the measurement object based on the generated synthetic three-dimensional shape data.

  Further, in the present embodiment, since the inclined portion 402 of the stage 140 can be switched between the horizontal posture and the inclined posture, the mounting surface 142a perpendicular to the rotation axis Ax and the rotation axis Ax are inclined. The inclined mounting surface 402a can be selectively used. Thereby, the posture of the measuring object S on the stage 140 can be easily adjusted according to the purpose.

  Further, in the present embodiment, target image data representing the target image GT and reference plane image data representing the reference plane image GS are respectively generated. The user can intuitively recognize the three-dimensional shape of the measuring object S by looking at the object image GT. Further, the user can easily specify the measurement location by using the reference plane image GS. Therefore, the required measurement value can be efficiently obtained by using the three-dimensional shape image data and the reference plane image data in order or selectively.

[9] Other Embodiments (1) FIGS. 33 and 34 are diagrams for explaining another configuration example of the stage 140. In the example of FIG. 33, the stage plate 142 includes two fixing portions 401u and 401v and an inclined portion 402. The inclined portion 402 is provided between the fixed portion 401u and the fixed portion 401v so that the inclination angle can be adjusted. In this case, the measurement target S can be placed on the center of the stage 140 in an inclined posture, and the measurement target S can be prevented from coming off the imaging region TR (FIG. 4). Further, by reducing the size of the inclined portion 402, the region of the measuring object S that overlaps the inclined portion 402 can be reduced, and three-dimensional shape data of a wider range of the measuring object S can be generated.

  In the example of FIG. 34, the stage plate 142 is not divided into the fixed portion 401 and the inclined portion 402. The tilting member 410 is mounted on the mounting surface 142a of the stage plate 142. The tilt member 410 is attachable to and detachable from the stage plate 142. The tilting member 410 has a tilted mounting surface 410a and a locking portion 411 for locking the measurement object S mounted on the tilted mounting surface 410a.

  In order to associate the rotational position of the stage 140 with the orientation of the inclined mounting surface 402a, it is preferable that the mounting position of the inclined member 410 on the mounting surface 142a be constant. In this example, the stage plate 142 is provided with a plurality of holes 142h, and the bottom surface of the inclined member 410 is provided with a plurality of protrusions 410b corresponding to the holes 142h. By inserting the protrusions 410b of the tilting member 410 into the plurality of holes 142h of the stage plate 142, the stage plate 142 is attached to a predetermined position on the mounting surface 142a. Instead of providing the hole 142h and the protrusion 410b, a mark or the like indicating the mounting position of the tilt member 410 may be attached to the stage plate 142.

  Also in this example, the measuring object S can be maintained in the inclined posture. Therefore, similarly to the above-described embodiment, it is possible to easily generate the point cloud data of the required portion of the measuring object S. In addition, the mounting surface 142a that is perpendicular to the rotation axis Ax and the tilt mounting surface 410a that slopes with respect to the rotation axis Ax can be selectively used by attaching and detaching the tilting member 410. Thereby, the posture of the measuring object S on the stage 140 can be easily adjusted according to the purpose.

  It should be noted that a plurality of types of tilt members 410 having different tilt angles of the tilt mounting surface 410a may be used. Further, in the one tilt member 410, the tilt angle of the tilt mounting surface 410a may be variable.

  (2) In the above embodiment, the CPU 210 synthesizes a plurality of three-dimensional shape data based on the rotational position of the stage 140, but the present invention is not limited to this. For example, when the user operates the stage operation unit 145 to rotate the stage 140, or when the user grips the measurement target S and changes the posture of the measurement target S, the user has a plurality of stereoscopic images. The shape data may be aligned and combined to generate combined three-dimensional shape data.

  (3) In the above-described embodiment, the reference plane is set by the user designating any surface of the measurement object S on the object image GT, but even if the reference plane is automatically set. Good. For example, as described above, the three-dimensional shape data is generated in the facing state, so that the object image GT showing the measurement object S in a plan view can be displayed. Therefore, in the object image GT, the surface of the measurement object S having the smallest inclination in the depth direction (the surface of the measurement object S having the smallest angle with respect to the imaging surface 120a of the light receiving unit 120) is specified, and the specified surface is specified. The plane having the highest degree of coincidence with may be extracted and set as the reference plane.

  (4) In the above embodiment, the monocular camera is used as the light receiving unit 120, but a compound eye camera may be used instead of the monocular camera or in addition to the monocular camera. In addition, a plurality of light receiving units 120 may be used and stereoscopic shape data may be generated by a stereo method. Further, in the above-described embodiment, two light projecting units 110 are used, but if it is possible to generate three-dimensional shape data, only one light projecting unit 110 may be used, or three or more light projecting units 110 may be used. The light unit 110 may be used.

  Further, when the live image data and the texture image data are acquired using the uniform measurement light from the light projecting unit 110, the illumination light output unit 130 and the illumination light source 320 may not be provided. It is also possible to generate texture image data by synthesizing pattern image data, and in that case, the illumination light output unit 130 and the illumination light source 320 may not be provided.

  Further, in the above embodiment, the pattern image data, the live image data, and the texture image data are acquired by the common light receiving unit 120. However, the light receiving unit for acquiring the three-dimensional shape data, the live image data, and the texture image data are acquired. May be separately provided.

  Further, in the above embodiment, the point cloud data is generated by the triangulation method, but the point cloud data may be generated by another method such as the TOF (Time Of Flight) method.

  (5) In the above embodiment, the stage drive unit 146 allows the stage 140 to rotate about the rotation axis Ax and does not move in other directions, but the present invention is not limited to this.

  The stage 140 may be configured to be rotatable about the rotation axis Ax and movable in at least one of the X direction, the Y direction, and the Z direction, for example. In this case, the rotation angle and the position of the stage 140 can be freely changed while the measurement target S is placed on the stage 140 in a fixed posture. Therefore, the measuring object S can be imaged from various viewpoints. As a result, it is possible to generate synthetic stereoscopic shape data of a wider range of the measuring object S.

[10] Correspondence between each component of the claims and each part of the embodiment Hereinafter, an example of the correspondence between each component of the claim and each part of the embodiment will be described, but the present invention is not limited to the following examples. Not limited.

  In the above embodiment, the installation unit 161 is an example of the stage holding unit, the stage 140 is an example of the stage, the inclined mounting surfaces 402a and 410a are examples of the inclined mounting surface, and the head unit 190 is the head. The light emitting unit 110 is an example of a light emitting unit, the light receiving unit 120 is an example of a light receiving unit, the stand unit 162 is an example of a connecting unit, and the point cloud data generation unit 501 is a point cloud. This is an example of data generating means, the synthesizing section 502 is an example of synthesizing means, the measuring section 503 is an example of a measuring means, the mounting surface 142a is an example of a non-inclined mounting surface, and the stage plate 142 is a stage. It is an example of a plate, the inclination member 410 is an example of an inclined portion, the rotation control unit 504 is an example of rotation control means, the imaging surface 120a is an example of an imaging surface, and the invalid portion setting unit 505 is an invalid portion setting. The stereoscopic image data generation unit 506 is an example of a stereoscopic image data generation unit, the reference plane setting unit 507 is an example of a reference plane setting unit, and the reference plane image data generation unit 508 is a reference plane. It is an example of image data generation means.

  As each constituent element of the claims, various other elements having the configurations or functions described in the claims may be used.

  INDUSTRIAL APPLICABILITY The present invention can be used for various measuring devices that measure an object to be measured.

100 measuring unit 110 light emitting unit 111 measuring light source 112 pattern generating unit 113, 114 lens 120 light receiving unit 130 illumination light output unit 140 stage 150 control board 200 PC
210 CPU
220 ROM
230 Working Memory 240 Storage Device 250 Operation Unit 300 Control Unit 320 Illumination Light Source 400 Display Unit 500 Measuring Device S Measurement Object

Claims (8)

A stage holder,
The stage holder is rotatably held about a vertical rotation axis and has a non-inclined mounting surface orthogonal to the rotation axis. One portion of the non-inclined mounting surface is the rotation axis. By being configured to be changeable between a non-inclined state that is orthogonal and an inclined state that is not orthogonal to the rotation axis, an inclined mounting surface that is non-perpendicular to the rotation axis and on which an object to be measured is placed is selectively selected. The stage to be formed ,
A light projecting unit that irradiates the measurement target placed on the stage with a measurement light having a pattern, and a light receiving unit that receives the measurement light reflected by the measurement target and outputs a light reception signal indicating a light reception amount. A head part including
The head unit and the stage holder are arranged so that the measuring light is guided obliquely downward from the light projecting unit to the measuring object, and the optical axis of the light receiving unit extends obliquely downward toward the measuring object. A connecting portion that fixedly connects the portion,
Point cloud data generating means for generating point cloud data representing a three-dimensional shape of the measurement object based on a light reception signal output by the light receiving unit;
A synthesizing means for synthesizing one point cloud data generated by the point cloud data generating means and another point cloud data to generate synthetic point cloud data;
A measuring device, comprising: a measuring unit that receives a designation of a portion to be measured of the measurement object, and calculates a measurement value of the designated portion based on the combined point cloud data generated by the combining unit. The stage has another non-tilted mounting surface different from the one portion, and a locking portion for locking the measurement object mounted on the inclined mounting surface, Item 1. The measuring device according to item 1. The stage is
A stage plate having the non-inclined mounting surface and held by the stage holding part;
The measuring device according to claim 1, further comprising: an inclined portion that has the inclined mounting surface as the one portion and is attachable to and detachable from the stage plate. The one part of the stage is
The measuring device according to any one of claims 1 to 3, which is provided so that an inclination angle with respect to a surface perpendicular to the rotation axis is adjustable so as to selectively form the inclined mounting surface . Further comprising a rotation control means for controlling the rotation of the stage,
The point cloud data generation means generates the one point cloud data based on a light reception signal output by the light reception unit when the rotation control means positions the stage at a first rotation position; Generating the other point cloud data based on a light reception signal output by the light receiving unit when the stage is located at the second rotation position by the rotation control means,
5. The synthesizing means synthesizes the one point cloud data and the other point cloud data based on the rotational position of the stage controlled by the rotation control means. The measuring device described. The light receiving unit has an imaging surface perpendicular to the optical axis,
The measurement device according to claim 5, wherein the rotation control unit controls a rotation position of the stage so that the inclined mounting surface faces the imaging surface of the light receiving unit. The measuring device according to any one of claims 1 to 6, further comprising invalid portion setting means for setting a portion to be invalidated in the synthetic point cloud data generated by the synthesizing means. Stereoscopic shape image data generating means for generating stereoscopic shape image data representing an image of the measurement object viewed in an arbitrary direction based on the synthetic point cloud data generated by the synthesizing means,
A reference plane setting unit that sets a reference plane that corresponds to a part of the surface of the measurement target represented by the synthesis point cloud data generated by the synthesis unit and serves as a measurement reference;
A reference plane for generating reference plane image data representing an image of the measurement object viewed perpendicularly to the reference plane set by the reference plane setting means, based on the synthesis point cloud data generated by the synthesis means. Further comprising image data generating means,
The measuring device according to any one of claims 1 to 7, wherein the measuring unit receives designation of a position to be measured with respect to one of the three-dimensional shape image data and the reference plane image data.

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