JP2021025917A - Three-dimensional shape measurement device - Google Patents

Abstract

To provide a three-dimensional shape measurement device that can avoid an unintended collision even if an object to be measured has a long size to protrude from a placement unit.SOLUTION: A three-dimensional shape measurement device 500 comprises: a placement unit 140 including a rotary stage 143 that rotates a placement surface 142 on which an object to be measured WK is placed and a translation stage 141 that translates the placement surface 142; a light projection unit 110 that irradiates the object to be measured WK with measurement light; a light receiving unit 120 that outputs a light receiving signal; a pedestal unit 600; a support unit 700 that is connected to the pedestal unit 600 and supports the light projection unit 110 and the light receiving unit 120; a point group data generation unit that generates point group data based on the light receiving signal; and a movement control unit 144 that, in a posture in which the translation stage 141 is at a reference position, controls the placement unit to translate the translation stage 141 by the minimum separation distance L2 or more, which is between an outer peripheral end OP of the placement unit 140 and a surface of the support unit 700 opposite to the outer peripheral end OP.SELECTED DRAWING: Figure 14

Description

The present invention relates to a three-dimensional shape measuring device for performing a predetermined inspection including height information on a three-dimensional measurement object.

A three-dimensional shape measuring device of a triangular ranging method is known (for example, Patent Document 1). In this three-dimensional shape measuring device, a mounting portion on which a measurement object is placed and a head portion that projects measurement light toward the measurement object or receives reflected light from the measurement object are provided. It is fixedly connected via a support portion. This enhances the robustness against changes in the external environment such as vibration resistance, and makes it possible to stably measure the three-dimensional shape of the object to be measured. Further, the three-dimensional shape measuring device is provided with a rotation stage for rotating the measurement object in order to measure the three-dimensional shape of the measurement object from a plurality of directions.

Japanese Unexamined Patent Publication No. 2018-4278

In such a three-dimensional shape measuring device, the size of the mounting portion on which the measurement object is placed is limited, and it is desirable to measure the three-dimensional shape of a long measurement object that does not fit in the mounting portion. is there. In such a case, when the amount of protrusion of the measurement object from the mounting portion is larger than the minimum separation distance from the outer peripheral end of the mounting portion to the support portion, in order to avoid interference between the measurement target and the support portion, It is necessary to regulate the rotational movement of the rotating stage.

One of the objects of the present invention is to provide a three-dimensional shape measuring device capable of avoiding an unintended collision even with a long measurement object that protrudes from the mounting portion.

Means for Solving Problems and Effects of Invention

According to the three-dimensional shape measuring device according to the first aspect of the present invention, the three-dimensional shape measuring device for measuring the three-dimensional shape of the object to be measured is a mounting surface on which the object to be measured is placed. A rotating stage that rotates around a rotation axis included in the mounting surface and the previously described mounting surface are moved in parallel in the plane to which the mounting surface belongs, with reference to a predetermined reference position included in the mounting surface. A mounting unit provided with a translational stage to be made to perform, a light projecting unit that irradiates a measurement object mounted on the above-mentioned mounting unit with measurement light having a predetermined pattern, and a measuring object irradiated by the light projecting unit. A light receiving unit that receives the measurement light reflected in the above and outputs a light receiving signal indicating the amount of light received, a pedestal portion that supports the above-mentioned pedestal portion, and an upper portion of the above-mentioned pedestal portion that are connected to the pedestal portion. Measurement is performed based on a support portion that fixedly supports the light projecting portion and the light receiving portion so that a measurement region by the measurement light is formed, and a light receiving signal output by the light receiving portion supported by the support portion. A point group data generation unit that generates point group data representing a three-dimensional shape of an object, and a translation stage in a posture in which the translation stage is in the reference position, A movement control unit that controls the above-mentioned mounting portion can be provided so that the support portion moves in parallel by a minimum separation distance or more from the facing surface. With the above configuration, even when measuring a long measurement object that does not fit in the mounting portion, by translating the mounting portion by the minimum separation distance or more, the end portion of the measurement object protruding from the mounting portion Can be moved inside the mounting portion, and collision between the measurement object and the support portion can be avoided.

Further, according to the three-dimensional shape measuring device according to the second side surface, in addition to the above configuration, the movement control unit protrudes from the previously described mounting portion of the measurement object mounted on the previously described mounting portion. The translational stage can be configured to move so that the end is within the measurement area. With the above configuration, even when measuring a long measurement object that does not fit in the mounting part, by translating the translational stage, the end of the measurement object protruding from the mounting part can be moved to the mounting part. It can be moved into the measurement area.

Further, according to the three-dimensional shape measuring device according to the third aspect, in addition to any of the above configurations, the movement control unit is a previously described mounting portion of a measurement object mounted on the previously described mounting portion. The direction in which the translational stage intersects the depth direction in which the preamble is approaching and separating from the support in the plan view of the preamble so that the end protruding from the measurement region is included in the measurement area ( * X direction), and can be configured to move toward the center side of the measurement region. With the above configuration, it is possible to move the end portion of the measurement object in the measurement region while avoiding the collision between the translation stage and the support portion.

Furthermore, according to the three-dimensional shape measuring device according to the fourth side surface, in addition to any of the above configurations, the measurement object mounted on the previously described mounting portion further protrudes from the previously described mounting portion. An end portion detecting portion for detecting an end portion can be provided. With the above configuration, it is possible to detect the end portion of the measurement object housed in the measurement area. In this way, by grasping the amount of protrusion of the end portion of the measurement object protruding from the mounting portion, it is possible to avoid a collision due to the movement of the mounting portion.

Furthermore, according to the three-dimensional shape measuring device according to the fifth side surface, in addition to any of the above configurations, the end detection unit uses the movement control unit to separate the translation stage from the reference position by the minimum distance. It can be configured to execute the end detection operation while being translated over a distance.

Furthermore, according to the three-dimensional shape measuring device according to the sixth aspect, in addition to any of the above configurations, the end detection unit is based on the point cloud data generated by the point cloud data generation unit. , Can be configured to detect the end.

Furthermore, according to the three-dimensional shape measuring device according to the seventh side surface, in addition to any of the above configurations, the end is further based on whether or not the end can be detected by the end detection unit or the detection position. A regulation determination unit for determining whether to restrict the rotational movement of the rotating stage or the translational movement of the translation stage in a direction in which the unit approaches the support unit can be provided. With the above configuration, it is possible to restrict the movement of the mounting portion so that the end portion of the object to be measured does not come into contact with the support portion.

Furthermore, according to the three-dimensional shape measuring device according to the eighth aspect, in addition to any of the above configurations, the regulation determination unit is a measurement target based on the end detection result by the end detection unit. It is possible to instruct the movement control unit to change the movement direction and / or the movement amount of the above-mentioned placement portion so that the end portion of the object does not approach the support portion. With the above configuration, it is possible to restrict the movement of the mounting portion so that the end portion of the object to be measured does not come into contact with the support portion.

Furthermore, according to the three-dimensional shape measuring device according to the ninth aspect surface, in addition to any of the above configurations, the regulation determination unit is based on the end detection result by the end detection unit, and the measurement object is measured. It can be configured to output an image, text or voice announcing that the end of the is approaching the support. With the above configuration, before the object to be measured comes into contact with the three-dimensional shape measuring device, the user can be notified by, for example, characters or voice, and prevention of contact can be promoted.

Furthermore, according to the three-dimensional shape measuring device according to the tenth side surface, in addition to any of the above configurations, the above-mentioned mounting portion is above the rotating stage rotatably supported by the pedestal portion. A translational stage can be provided. With the above configuration, the rotating stage is rotatably fixed to the pedestal portion, and the translation stage can be rotated together with the measurement object placed on the translation stage. By rotating the measurement object and the translation stage together, the positional relationship between the measurement object and the translation stage can be maintained constant as long as the placement posture of the measurement object is not changed. As a result, three-dimensional measurement from a plurality of viewpoints in rotation can always be performed within the same measurement target range. As a result, the same point on the measurement object can be averaged with data from a plurality of viewpoints, stable measurement can be realized over the entire measurement object, and measurement accuracy can be improved.

Furthermore, according to the three-dimensional shape measuring device according to the eleventh side surface, in addition to any of the above configurations, the translational stage can be made into a circular shape. With the above configuration, by using a circular translation stage, the operation of the translation stage can be smoothed, and the diameter is almost uniform, so that the user can easily grasp the maximum diameter.

It is a block diagram which shows the image inspection apparatus which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the measuring part of FIG. It is a block diagram which shows the structure of the CPU of the controller of FIG. It is a block diagram which shows the 3D shape measurement system. It is an exploded perspective view of the 3D shape measuring apparatus main body shown in FIG. It is a side view of the 3D shape measuring apparatus main body shown in FIG. It is a side view of the three-dimensional shape measuring apparatus provided with a plurality of light receiving parts having different magnifications. It is a top view which shows the driving direction of a mounting surface. It is a top view which shows the driving direction of a mounting surface. FIG. 10A is a schematic plan view showing the relationship between the mounting surface and the measurement area, FIG. 10B is a schematic plan view of the translation stage moved to the left, and FIG. 10C is a schematic plan view of the translation stage moved to the right. FIG. 10D is a schematic plan view of a state in which the translational stage is moved to the left while the rotation stage is rotated by 180 °, and FIG. 13E is a schematic plan view of a state in which the translational stage is moved to the right. 11A is an observation image of the measurement object acquired at the position of FIG. 10B, FIG. 11B is a single-field measurement data generated from the observation image of FIG. 11A, and FIG. 11C is an observation image of the measurement object acquired at the position of FIG. 10C. 11D is the single-field measurement data generated from the observation image of FIG. 11C, FIG. 11E is the observation image of the measurement object acquired at the position of FIG. 10D, and FIG. 11F is the single-field measurement data generated from the observation image of FIG. 11E. 11G is an observation image of the measurement object acquired at the position of FIG. 10E, FIG. 11H is single-field measurement data generated from the observation image of FIG. 11G, and FIG. 11I is a composite of FIGS. 11B, 11D, 11F and 11H. It is each image figure of the image. FIG. 12A is a schematic plan view showing a state in which the measurement object does not protrude from the mounting portion, FIG. 12B is a schematic plan view showing a state in which the measurement object can rotate the rotating stage without interfering with the support column, and FIG. 12C is a schematic plan view. It is a schematic plan view which shows the state which a measurement object collides with a support column part. It is a schematic plan view which shows the state which the mounting surface is rectangular. FIG. 14A is a schematic plan view showing a state in which the end portion of the object to be measured cannot be detected, and FIG. 14B is a schematic plan view showing a state in which the translational stage is translated. 15A is a plan view of the translation stage according to the modification, FIG. 15B is a plan view of the translation stage according to another modification, and FIG. 15C is a plan view of the translation stage according to the further modification. It is a block diagram which shows the 3D shape measuring apparatus which concerns on a modification. It is an image diagram which shows the example which superposed the contour pixel on the top view map image of the measurement object. It is an image diagram which shows the example of the mesh image which performs the edge detection. It is an image diagram which shows the state which superposed the contour line which detected the end part of the measurement object with the mesh image of FIG. 18 as a plan view.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments shown below exemplify a three-dimensional shape measuring device and a three-dimensional shape measuring method for embodying the technical idea of the present invention, and the present invention is a three-dimensional shape measuring device and a tertiary. The original shape measurement method is not specified as follows. Further, the present specification does not specify the member shown in the claims as the member of the embodiment. In particular, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of the present invention to the specific description unless otherwise specified, and are merely described. It's just an example. The size and positional relationship of the members shown in each drawing may be exaggerated to clarify the explanation. Further, in the following description, members of the same or the same quality are shown with the same name and reference numeral, and detailed description thereof will be omitted as appropriate. Further, each element constituting the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, the function of one member is performed by the plurality of members. It can also be shared and realized.

In the present specification, the "texture image" is an observation image having texture information represented by an optical image. On the other hand, the "height image" is also called a distance image or the like, and is used to mean an image including height information. For example, an image in which height information is converted into brightness, chromaticity, etc. and displayed as a two-dimensional image, and an image in which height information is displayed as Z coordinate information in a three-dimensional manner can be mentioned. The height image also includes a three-dimensional composite image in which a texture image is pasted as texture information on such a height image. Further, in the present specification, the display form of the height image is not limited to the one displayed in a two-dimensional shape, but also includes the one displayed in a three-dimensional shape. For example, the height information of the height image is converted into brightness and displayed as a two-dimensional image, and the height information is displayed as Z coordinate information in a three-dimensional manner.

Further, in the present specification, the "posture" of placing the measurement object on the stage means the rotation angle of the measurement object. When the object to be measured has a point-symmetrical shape in a plan view such as a cone, the same result can be obtained regardless of the rotation angle, so it is not necessary to specify the posture.

In the following embodiment, in order to acquire height information of the measurement object, a predetermined pattern of measurement light is applied to the measurement object, and a signal obtained from the reflected light reflected on the surface of the measurement object is obtained. The height information is acquired using. For example, as the measurement light of a predetermined pattern, a measurement method using a triangular distance measurement using a fringe projection image obtained by projecting onto a measurement object using structured illumination and using the reflected light can be used. However, the present invention is not limited to this, and other methods can be applied to the principle and configuration for acquiring the height information of the object to be measured.
(Embodiment)

The three-dimensional shape measuring device can measure the three-dimensional height of the image to be measured. In addition to three-dimensional measurement, two-dimensional dimensional measurement can also be performed. FIG. 1 shows a block diagram of a three-dimensional shape measuring device according to an embodiment of the present invention. The three-dimensional shape measuring device 500 shown in this figure includes a measuring unit 100, a pedestal unit 600, a controller 200, a light source unit 300, and a display unit 400. The three-dimensional shape measuring device 500 performs structured illumination with the light source unit 300, captures a fringe projection image to generate a height image having height information, and based on this, three-dimensional dimensions of the measurement object WK. And shape can be measured. The measurement using such fringe projection has an advantage that the measurement time can be shortened because the height can be measured without moving the optical system such as the measurement object WK or the lens in the Z direction.

The measuring unit 100 includes a light emitting unit 110, a light receiving unit 120, a measurement control unit 150, and an illumination light output unit 130. The light projecting unit 110 irradiates the measurement object WK placed on the mounting unit 140 with measurement light having a predetermined pattern. The light receiving unit 120 is fixed to the mounting surface 142 in an inclined posture. The light receiving unit 120 receives the measurement light that is irradiated by the light projecting unit 110 and reflected by the measurement object WK, and outputs a light receiving signal indicating the amount of light received.

The pedestal unit 600 includes a mounting unit 140 and a movement control unit 144. The pedestal portion 600 supports the mounting portion 140. The movement control unit 144 is a member that moves the mounting unit 140. The movement control unit 144 may be provided on the pedestal unit 600 side or may be arranged on the controller side.

The light source unit 300 is connected to the measurement unit 100. The light source unit 300 generates measurement light and supplies it to the measurement unit 100. The controller 200 controls the imaging of the measuring unit 100. The display unit 400 is connected to the controller 200 and serves as an HMI that displays the generated image and makes necessary settings.
(Mounting unit 140)

The pedestal portion 600 shown in FIG. 1 includes a mounting portion 140 and a movement control portion 144. The mounting unit 140 has a mounting surface 142 on which the measurement object WK is mounted. The mounting portion 140 includes a rotating stage 143 that rotates the mounting surface 142 and a translation stage 141 that translates the mounting surface 142.
(Movement control unit 144)

The movement control unit 144 controls the rotational movement of the rotary stage 143 and the translational movement of the translation stage 141 based on the measurement area set by the measurement area setting unit 264. Further, the movement control unit 144 controls the movement operation of the mounting unit 140 by the mounting movement unit based on the measurement area set by the measurement area setting unit 264 described later.

The controller 200 includes a CPU (central processing unit) 210, a ROM (read-only memory) 220, a working memory 230, a storage device 240, and an operation unit 250. A PC (personal computer) or the like can be used as the controller 200. Further, the CPU 210 has a point cloud data generation unit 260 that generates point cloud data, an end detection unit 265 that detects the end of the measurement object mounted on the mounting unit, and an end portion by the end detection unit 265. The function of the regulation determination unit 266 that determines whether or not to restrict the movement of the mounting unit is realized based on the detection possibility or the detection position of the above (details will be described later).
(Block diagram of measuring unit 100)

The configuration of the measuring unit 100 of the three-dimensional shape measuring device 500 of FIG. 1 is shown in the block diagram of FIG. The measuring unit 100 is, for example, a microscope, and includes a light emitting unit 110, a light receiving unit 120, an illumination light output unit 130, a measurement control unit 150, a main body case 101 for accommodating these, and a mounting unit 140. The light projecting unit 110 includes a measurement light source 111, a pattern generation unit 112, and a plurality of lenses 113, 114, 115. The light receiving unit 120 includes a camera 121 and a plurality of lenses 122 and 123. The object to be measured WK is placed on the mounting portion 140. The main body case 101 is a housing made of resin or metal.
(Light projecting unit 110)

The light projecting unit 110 is arranged diagonally above the mounting unit 140. The measuring unit 100 may include a plurality of light projecting units 110. In the example of FIG. 2, the measuring unit 100 includes two projecting units 110. Here, the first measurement light projecting unit 110A (on the right side in FIG. 2) capable of irradiating the measurement object WK with the first measurement light ML1 from the first direction, and the second measurement object WK different from the first direction. The second measurement light projection unit 110B (on the left side in FIG. 2) capable of irradiating the measurement object WK with the second measurement light ML2 from the direction is arranged respectively. The first measurement light projection unit 110A and the second measurement light projection unit 110B are symmetrically arranged with the optical axis of the light receiving unit 120 interposed therebetween. It is also possible to provide three or more light projecting units, or to move the light projecting unit and the stage relative to each other so that the light projecting can be projected in different directions while using a common light projecting unit. Further, in the above example, a plurality of light emitting units 110 are prepared and a common light receiving unit 120 receives light, but conversely, a plurality of light receiving units are prepared and received light for the common light emitting unit. It may be configured. Further, in this example, the irradiation angle of the illumination light projected by the light projecting unit in the vertical direction is fixed, but this can also be made variable.
(Measurement light source 111)

Each of the first measurement light projection unit 110A and the second measurement light projection unit 110B includes a first measurement light source and a second measurement light source as measurement light sources 111, respectively. The measurement light source 11 is, for example, a halogen lamp that emits white light. The measurement light source 111 may be a light source that emits monochromatic light, for example, another light source such as a white LED (light emitting diode) that emits white light or an organic EL. The light emitted from the measurement light source 111 (hereinafter, referred to as “measurement light”) is appropriately focused by the lens 113 and then incident on the pattern generation unit 112.
(Pattern generator 112)

The pattern generation unit 112 reflects the light emitted from the measurement light source 111 so that the measurement light is projected onto the measurement object WK. The measurement light incident on the pattern generation unit 112 is converted into a preset pattern and a preset intensity (brightness) and emitted. The measurement light emitted by the pattern generation unit 112 is converted into light having a diameter larger than the observable / measurable field of view of the light receiving unit 120 by the plurality of lenses 114 and 115, and then the measurement target on the mounting unit 140. The object WK is irradiated.

The pattern generation unit 112 is a member capable of switching between a projection state in which the measurement light is projected onto the measurement object WK and a non-projection state in which the measurement light is not projected on the measurement object WK. For such a pattern generation unit 112, for example, a DMD (Digital Micromirror Device) can be preferably used. The pattern generation unit 112 using the DMD is controlled by the measurement control unit 150 so as to be able to switch between a reflection state in which the measurement light is reflected on the optical path as a light projection state and a light shielding state in which the measurement light is blocked as a non-light projection state. it can.

A DMD is an element in which a large number of micromirror (micromirror surface) MMs are arranged on a plane. Since each micromirror can be individually switched between the ON state and the OFF state by the measurement control unit 150, a desired projection pattern can be configured by combining the ON state and the OFF state of a large number of micromirrors. As a result, the pattern required for triangular distance measurement can be generated, and the measurement target WK can be measured. In this way, the DMD functions as a projection pattern optical system that projects a periodic projection pattern for measurement onto the measurement object WK at the time of measurement. In addition, DMD has an excellent response speed, and has an advantage that it can be operated at a higher speed than a shutter or the like.

In the above examples, an example in which DMD is used for the pattern generation unit 112 has been described, but the present invention does not limit the pattern generation unit 112 to DMD, and other members can also be used. For example, LCOS (Liquid Crystal on Silicon: reflective liquid crystal element) may be used as the pattern generation unit 112. Alternatively, a transmissive member may be used instead of the reflective member to adjust the amount of transmitted light. In this case, the pattern generation unit 112 is arranged on the optical path of the measurement light to switch between a light projection state in which the measurement light is transmitted and a light shielding state in which the measurement light is blocked. For such a pattern generation unit 112, for example, an LCD (liquid crystal display) can be used. Alternatively, a projection method using a multi-line LED, a projection method using a plurality of optical paths, an optical scanner method composed of a laser and a galvanometer mirror, etc., and interferometry generated by superimposing beams divided by a beam splitter are used. The pattern generation unit 112 may be configured by an AFI (Accordion fringe interferometry) method, a projection method using a physical lattice composed of a piezostage and a high-resolution encoder, and a moving mechanism.

Further, in the example of FIG. 2 and the like, an example in which two measurement light projection units are provided has been described, but the present invention is not limited to this, and it is possible to provide three or more measurement light projection units. Alternatively, the number of measurement light projection units may be one. In this case, by making the position of the measurement light projection unit movable, the measurement light can be projected onto the measurement object WK from different directions.
(Light receiving unit 120)

The light receiving unit 120 is arranged above the mounting unit 140. The measurement light reflected above the mounting portion 140 by the measurement object WK is collected and imaged by the plurality of lenses 122 and 123 of the light receiving portion 120, and then received by the camera 121.
(Camera 121)

The camera 121 is, for example, a CCD (charge-coupled device) camera including an image sensor 121a and a lens. The image pickup device 121a is, for example, a monochrome CCD (charge-coupled device). The image pickup device 121a may be another image pickup device such as a CMOS (complementary metal oxide semiconductor) image sensor. Since each pixel of a color image sensor needs to correspond to light reception for red, green, and blue, the measurement resolution is lower than that of a monochrome image sensor, and it is necessary to provide a color filter for each pixel. Sensitivity decreases. Therefore, in the present embodiment, a monochrome CCD is used as the image pickup element, and a color image is acquired by irradiating the illumination light output unit 130, which will be described later, with illumination corresponding to RGB in a time-divided manner for imaging. There is. With such a configuration, it is possible to acquire a color image of the measured object without deteriorating the measurement accuracy.

However, it goes without saying that a color image sensor may be used as the image sensor 121a. In this case, although the measurement accuracy and sensitivity are lowered, it is not necessary to irradiate the illumination light output unit 130 with the illumination corresponding to RGB in time division, and the color image can be acquired only by irradiating the white light. The optical system can be configured simply. From each pixel of the image sensor 121a, an analog electric signal (hereinafter, referred to as “light receiving signal”) corresponding to the amount of received light is output to the measurement control unit 150.

The image of the measurement object WK captured in this way has an extremely accurate similarity to the measurement object WK due to the characteristics of the lens. Further, by calibrating using the magnification of the lens, it is possible to accurately associate the dimensions on the image with the dimensions on the actual measurement object WK.
(Measurement control unit 150)

An A / D converter (analog / digital converter) and a FIFO (First In First Out) memory (not shown) are mounted on the measurement control unit 150. The received light signal output from the camera 121 is sampled at a constant sampling cycle by the A / D converter of the measurement control unit 150 and converted into a digital signal based on the control by the light source 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 controller 200 as pixel data.
(Controller 200)

As shown in FIG. 1, the controller 200 includes a CPU 210, a ROM 220, a working memory 230, a storage device 240, and an operation unit 250. The operation unit 250 can include a keyboard and a pointing device. As the pointing device, a mouse, a joystick, or the like is used.

The system program is stored in the ROM 220. The working memory 230 comprises 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 three-dimensional shape measurement program for operating the three-dimensional shape measurement device. Further, the storage device 240 is used to store various data such as pixel data given by the measurement control unit 150. Further, the storage device stores the luminance information, the height information, and the attribute information for each pixel constituting the measurement image.
(CPU210)

The CPU 210 is a control circuit or control element that processes a given signal or data, performs various calculations, and outputs a calculation result. In the present specification, the CPU means an element or a circuit that performs an operation, and is not limited to a CPU for a general-purpose PC or a processor such as an MPU, GPU, or TPU, regardless of its name, and is not limited to an FPGA, an ASIC, or an LSI. It is used in the sense that it includes a processor such as a processor, a microcomputer, or a chipset such as an ASIC.

The CPU 210 generates image data based on the pixel data given by the measurement control unit 150. Further, the CPU 210 performs various processes on the generated image data by using the working memory 230, and displays an image based on the image data on the display unit 400. A block diagram of the CPU 210 is shown in FIG. This CPU includes a point cloud data generation unit 260, a top view map image generation unit 261, a measurement area setting unit 264, an end detection unit 265, a regulation determination unit 266, a height image acquisition unit 228, and points. The functions of the group data synthesis unit 211, the image inspection unit 216, and the like are realized.
(End detection unit 265)

The end detection unit 265 detects the end of the measurement object WK mounted on the mounting unit 140 that protrudes from the mounting unit 140. The end detection unit 265 is configured to determine the rotation direction in which the rotation stage 143 is rotationally moved based on the detection result when one end of the measurement object WK is detected and the other end is not detected. You may. By doing so, the rotation direction can be determined so as to avoid the rotation direction in which the detected end portion interferes with the rotation of the rotation stage 143, so that the safety of the rotation operation is enhanced.

Further, when none of the ends of the object to be measured WK is detected, the end detection unit 265 prompts the user to select whether or not to rotate the rotation stage 143, or is placed on a mounting table. It may be configured to guide the user to reposition the measurement object WK. By doing so, even if neither end of the measurement object WK is detected, the user can be asked to select whether to rotate the measurement object WK or to replace the measurement object WK. It can be expected that the user will select a highly secure option.

Further, the end detection unit 265 may determine the allowance or regulation of the translational movement of the translation stage 141.
(Regulatory Judgment Department 266)

The regulation determination unit 266 rotates the rotation stage 143 in the direction in which the end portion approaches the support column 702, or translates the translation stage 141, based on whether or not the end portion can be detected by the end detection unit 265 or the detection position. Decide whether to regulate movement. As a result, the measurement object WK can be operated so as to avoid interfering with the three-dimensional shape measuring device.

The regulation determination unit 266 can output the result of determination based on the detection possibility and the detection position in various forms. For example, the regulation determination unit 266 may collide if the end of the object to be measured WK is approaching the support column 702 as a result of the end detection by the end detection unit 265, or if the measurement is continued as it is. The user is notified of such things by blinking a lamp, a buzzer, a voice such as a warning message, or text, an image, or a video. In this way, by giving a warning to the user before the measurement object WK comes into contact with the three-dimensional shape measuring device, it is possible to promote appropriate measures such as workarounds and preventive measures.

Based on the end detection result by the end detection unit 265, the regulation determination unit 266 determines the movement direction and / or movement amount of the mounting unit 140 so that the end of the measurement object WK does not approach the support column 702. The movement control unit 144 can be instructed to change. This makes it possible to limit the movement of the mounting portion 140 so that the end portion of the measurement object WK does not come into contact with the support column portion 702. Further, the regulation determination unit 266 may determine the rotation direction for rotating the rotation stage 143 based on the end detection result by the end detection unit 265.

The end detection unit 265 can detect the end based on the point cloud data generated by the point cloud data generation unit 260. At this time, the end portion may be detected directly from the point cloud data generated by the point cloud data generation unit 260. Alternatively, it is extracted from the top view map image showing the plan view when the measurement object WK placed on the mounting unit 140 is looked down from directly above, which is generated by the top view map image generation unit based on the point group data. The end portion may be detected based on the contour of the measured object WK. As a result, by using the top view map image of the measurement target WK viewed from directly above, the outline of the plan view of the measurement target WK can be obtained, so that the end portion can be easily grasped and the accuracy of collision avoidance can be improved. The advantage of improving accuracy is obtained. For extracting the contour of the object to be measured, a known method such as edge extraction for extracting the outer edge constituting the outer shape of the object to be measured can be used.
(Point cloud data generation unit 260)

The point cloud data generation unit 260 generates point cloud data, which is a set of points having three-dimensional position information representing the three-dimensional shape of the measurement target WK, based on the light receiving signal output by the light receiving unit 120.
(Top view map image generation unit 261)

The top view map image generation unit 261 directly above the measurement object WK mounted on the mounting unit 140 based on the point cloud data generated by the point cloud data generation unit 260 (including via the * mesh). Generates a top view map image showing a plan view when looking down from. By generating a top view map image of the measurement object WK viewed from directly above, the overall shape of the measurement object WK can be easily grasped, and thus the measurement area can be easily set. For example, the top view map image generation unit 261 uses the point cloud data generated by the point cloud data generation unit 260 as a two-dimensional texture image obtained by imaging the measurement target WK by the light receiving unit 120, and three-dimensionally captures the point cloud data. A top view map image is generated by pasting each position information. Alternatively, a mesh image in which polygons are attached to each point of the point cloud data generated by the point cloud data generation unit 260 to form a surface shape may be generated. A top view map image is generated from this mesh image. The mesh image may be generated by the top view map image generation unit 261 or may be generated by the mesh image generation unit. FIG. 3 shows an example of realizing a mesh image generation unit 262 that generates a mesh image with the CPU 210.
(Measurement area setting unit 264)

The measurement area setting unit 264 sets the measurement area on the top view map image displayed in the top view map image display area.

The height image acquisition unit 228 acquires a height image having height information based on a plurality of fringe projection images. Further, the point cloud data synthesis unit 211 synthesizes a plurality of point cloud data generated by the point cloud data generation unit 260. Here, the point cloud is also called a point cloud or the like, and has coordinates in a three-dimensional space (for example, Cartesian coordinates of XYZ). Therefore, by superimposing the point cloud data of the measurement object generated at different positions of the mounting unit on the coordinates of the common three-dimensional space by the point cloud data generation unit 211, more detailed and precise measurement can be performed. The surface shape of the object can be expressed.
(Image Inspection Department 216)

The image inspection unit 216 executes a predetermined image inspection on the image of the measurement object WK captured by the measurement unit 100. The image inspection unit 216 can include a measurement unit 216b for performing a predetermined measurement on the image to be measured. As a result, the image inspection can be executed based on the measurement result measured by the measurement unit 216b. For example, based on the result of measurement such as the length and angle of a predetermined portion of the object to be measured WK, it is possible to perform an inspection such as determination of a non-defective product or a defect. For the measurement performed by the measuring unit 216b, the contour line cut on the plane perpendicular to the screen is calculated by passing through the profile line specified on the texture image and displayed on the display unit 400 as a profile graph, or the profile graph. It is possible to extract circles and straight lines from the contour lines shown by and obtain their radii and distances.

As described above, the CPU 210 also uses different means for realizing various functions. However, it is needless to say that the configuration is not limited to a configuration in which one member also serves a plurality of means, and it is also possible to provide a plurality of members or members that realize functions separately or separately.
(Display unit 400)

The display unit 400 displays a fringe projection image acquired by the measurement unit 100, a height image generated by the height image acquisition unit 228 based on the fringe projection image, or a texture image captured by the measurement unit 100. It is a member of. The display unit 400 is composed of, for example, an LCD panel or an organic EL (electroluminescence) panel. Furthermore, by using a touch panel for the display unit, it can also be used as an operation unit.

Further, the display unit 400 displays the top view map image generated by the top view map image generation unit 261.
(Mounting unit 140)

In FIG. 2, two directions orthogonal to each other in the plane (hereinafter, referred to as “mounting surface”) on the mounting portion 140 on which the measurement object WK is mounted are defined as the X direction and the Y direction, respectively. It is indicated by arrows X and Y. The direction orthogonal to the mounting surface 142 of the mounting portion 140 is defined as the Z direction, and is indicated by an arrow Z. The direction of rotation about an axis parallel to the Z direction is defined as the θ direction, and is indicated by the arrow θ.

The mounting unit 140 includes a translation stage 141 and a rotation stage 143. The translation stage 141 has an X-direction moving mechanism and a Y-direction moving mechanism. The rotation stage 143 has a θ-direction rotation mechanism. The mounting portion 140 is configured by the translation stage 141 and the rotation stage 143. Further, the mounting portion 140 may include a fixing member (clamp) for fixing the measurement object WK on the mounting surface 142. Further, the mounting portion 140 may include a tilt stage having a mechanism that can rotate about an axis parallel to the mounting surface 142.

Here, as shown in FIG. 2, the central axes of the left and right light projecting units 110 and the central axes of the light receiving unit 120 are the arrangement of the measurement object WK on the mounting unit 140 and the covering of the light emitting unit 110 and the light receiving unit 120. The relative positional relationship between the light receiving unit 120, the light emitting unit 110, and the mounting unit 140 is determined so that they intersect at positions where the depth of field is appropriate. Further, since the center of the rotation axis in the θ direction coincides with the central axis of the light receiving unit 120, the rotation axis does not deviate from the field of view when the mounting unit 140 rotates in the θ direction. It is designed to rotate in the field of view around. In this figure, the measuring unit 100 has an arrangement rotated about the X direction on the paper surface, and the optical axis of the light receiving unit 120 and the top normal line (Z direction) of the mounting unit 140 do not necessarily coincide with each other. There is no need.
(Light source unit 300)

The light source unit 300 includes a control board 310 and an illumination light source 320 for observation. A CPU (not shown) is mounted on the control board 310. The CPU of the control board 310 controls the light projecting unit 110, the light receiving unit 120, and the measurement control unit 150 based on a command from the CPU 210 of the controller 200. Note that this configuration is an example, and other configurations may be used. For example, the measurement control unit 150 may control the light projecting unit 110 and the light receiving unit 120, or the controller 200 may control the light emitting unit 110 and the light receiving unit 120, so that the control board may be omitted. Alternatively, the light source unit 300 may be provided with a power supply circuit for driving the measurement unit 100.
(Illumination light source for observation 320)

The observation illumination light source 320 includes, for example, three-color LEDs that emit red light, green light, and blue light. By controlling the brightness of the light emitted from each LED, light of an arbitrary color can be generated from the observation illumination light source 320. The illumination light IL generated from the observation illumination light source 320 is output from the illumination light output unit 130 of the measurement unit 100 through the light guide member (light guide). In addition to LEDs, other light sources such as semiconductor lasers (LDs), halogen lights, and HIDs can be appropriately used as the observation illumination light sources. In particular, when a color image sensor is used as the image sensor, a white light source can be used as the observation illumination light source.

The illumination light IL output from the illumination light output unit 130 switches between red light, green light, and blue light in a time-divided manner to irradiate the measurement target WK. As a result, the texture images captured by each of these RGB lights can be combined to obtain a color texture image and displayed on the display unit 400.

The illumination light output unit 130 of FIG. 2 has a ring shape and is arranged above the mounting unit 140 so as to surround the light receiving unit 120. As a result, the illumination light output unit 130 irradiates the measurement object WK with illumination light in a ring shape so as not to generate a shadow.

In addition to such ring illumination, the illumination light output unit 130 can also add transmission illumination and coaxial epi-illumination. In the example of FIG. 2, a transmission illumination unit is provided on the mounting unit 140. The transmission illumination unit illuminates the measurement object WK from below the mounting unit 140. Therefore, the mounting portion 140 is provided with a transmission illumination light source, a reflector, and an illumination lens system.

The ring illumination and the transmitted illumination can be omitted as appropriate. When these are omitted, it is also possible to take a two-dimensional image by using the illumination for three-dimensional measurement, that is, the light projecting unit.

In the example of FIG. 1, the observation illumination light source 320 is not included in the main body case 101, and the observation illumination light source 320 is arranged in the light source unit 300 as an external attachment to the measurement unit 100. By doing so, it is possible to easily improve the quality of the illumination light supplied from the observation illumination light source 320. For example, since each of the RGB LEDs constituting the observation illumination light source 320 has different light distribution characteristics, when each of the RGB texture images is captured by the monochrome image pickup element 121a, the illumination color unevenness occurs in the field of view as it is. .. Therefore, a dedicated optical system that matches the light distribution characteristics of each LED is individually prepared and combined to absorb the difference in the light distribution characteristics, create uniform white illumination with no color unevenness, and then use the measuring unit 100. Can be introduced.

Further, it is possible to avoid a situation in which the heat generated by the observation illumination light source 320 affects the optical system of the measuring unit 100. That is, if there is a heat source in the vicinity of the members of the optical system, the dimensions may be out of order due to thermal expansion, and the measurement accuracy may decrease. However, by removing the observation illumination light source, which is the heat generation source, from the main body case 101, It is possible to avoid the problem caused by the heat generation of the observation illumination light source. Further, as a result, there is an advantage that a high-power light source having a large calorific value can be used as an observation illumination light source.

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. The light emitted from the measurement light source 111 (hereinafter referred to as measurement light) is appropriately focused by the lens 113 and then enters the pattern generation unit 112.

The pattern generator 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: reflective liquid crystal element), or a mask. The measurement light incident on the pattern generation unit 112 is converted into a preset pattern and a preset intensity (brightness) and emitted. The measurement light emitted from the pattern generation unit 112 is converted into light having a diameter larger than the size of the measurement object WK by the lens 114, and then irradiated to the measurement object WK on the mounting unit 140.

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 substantially parallel to the optical axis 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 substantially parallel to the optical axis 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 generation unit 112. As a result, the optical axes of the light emitting units 110A and 110B are inclined with respect to the optical axis of the light receiving unit 120, and the measurement light is emitted from both sides of the light receiving unit 120 toward the measurement object WK, respectively.

In the present embodiment, the light projecting units 110A and 110B are configured to have a constant angle of view in order to widen the irradiation range of the measurement light. The angles of view of the light projecting units 110A and 110B are determined, for example, by the dimensions of the pattern generation unit 112 and the focal length of the lens 114. When it is not necessary to widen the irradiation range of the measurement light, a telecentric optical system having an angle of view of approximately 0 degrees may be used for each of the light projecting units 110A and 110B.

The measurement light reflected above the mounting unit 140 by the measurement object WK is focused and imaged by the lens 122 of the light receiving unit 120, and is received by the image sensor 121a of the camera 121.

In the present embodiment, the light receiving unit 120 is configured to have a constant angle of view in order to widen the imaging field of view of the light receiving unit 120. In the present embodiment, the imaging field of view of the light receiving unit 120 means a region in space where imaging can be performed by the light receiving unit 120. The angle of view of the light receiving unit 120 is determined, for example, by the dimensions of the image sensor 121a and the focal length of the lens 122. If a wide field of view is not required, a telecentric optical system may be used for the light receiving unit 120. Here, the magnifications of the lenses 122 of the two light receiving units 120 provided in the measuring unit 100 are different from each other. Thereby, by selectively using the two light receiving units 120, the measurement object WK can be imaged at two different magnifications. It is preferable that the two light receiving units 120 are arranged so that the optical axes of the two light receiving units 120 are 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 pickup device 121a may be another image pickup device 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 receiving signal) corresponding to the amount of received light 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 having a red wavelength, a pixel that receives light having a green wavelength, and a pixel that receives light having a blue wavelength. Here, when a specific wavelength such as a blue wavelength is adopted as the measurement light, the color CCD can use only the pixels that receive the light of the specific wavelength for the measurement, but the monochrome CCD has no such restriction. Therefore, the measurement resolution of the monochrome CCD is higher than the resolution of the color CCD. Further, unlike a color CCD, a 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. Therefore, the point cloud data described later can be obtained with high accuracy. For these reasons, the camera 121 in this embodiment is provided with a monochrome CCD.

In the present embodiment, the illumination light output unit 130 emits red wavelength light, green wavelength light, and blue wavelength light to the measurement object WK in a time-divided manner. According to this configuration, a color image of the measurement object WK can be captured by the light receiving unit 120 using the monochrome CCD.

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

FIG. 4 shows a three-dimensional shape measuring system 1000 including the three-dimensional shape measuring device 500 according to the present embodiment. The three-dimensional shape measuring system 1000 shown in this figure inputs a control PC 1, a monitor 2, a keyboard 3, a mouse, etc. to the three-dimensional shape measuring device 500 composed of a three-dimensional shape measuring device main body 500A and a controller 200. The device 4 is connected. A three-dimensional shape measurement program for performing three-dimensional shape measurement using the three-dimensional shape measuring device 500 is installed in the control PC 1. The user can instruct the setting, imaging, measurement, and the like of the three-dimensional shape measuring device 500 by using the three-dimensional shape measuring program.

In the example of FIG. 4, the controller 200 is configured separately from the three-dimensional shape measuring device main body 500A, but the controller may be integrated on the three-dimensional shape measuring device main body side. Alternatively, the function of the controller can be integrated with the control PC.

The three-dimensional shape measuring device 500 includes a measuring unit 100, a support unit 700, a pedestal unit 600, and a light-shielding cover 102. The measuring unit 100, the support unit 700, the pedestal unit 600, and the light-shielding cover 102 are configured as a detachable unit type as shown in the exploded perspective view of FIG. This is advantageous for maintainability and portability of each member. The light-shielding cover 102 is extended in front of the light receiving unit 120 and the light emitting unit 110 to cover them, and is held above the mounting surface 142 in a posture separated from the mounting surface 142. The upper measurement area is shielded from outside light. The light-shielding cover 102 is removable according to the object to be measured, and the basic minimum configuration in measurement is a combination of the measuring unit 100 and the pedestal unit 600.

The pedestal portion 600 includes a mounting portion 140. The mounting unit 140 includes a rotating stage 143 that rotates the mounting surface 142 on which the object to be measured is mounted as described above, and a translation stage 141 that translates the mounting surface 142. Here, the mounting portion 140 is composed of an XY θ stage in which the XY stage, which is the translation stage 141, is mounted on the upper surface of the θ stage, which is the rotation stage 143.

The pedestal portion 600 holds the measuring portion 100 in a vertical posture via the support portion 700. Further, the measuring unit 100 fixes the light emitting unit 110 and the light receiving unit 120 in a posture in which the optical axis is inclined with respect to the mounting surface 142. Therefore, the measuring unit 100 includes a fixing unit 125 for fixing the light emitting unit 110 and the light receiving unit 120. As shown in FIG. 7, which will be described later, the fixing portion 125 is supported by the support column portion 702 in a posture separated from the pedestal portion 600. Further, the light projecting unit 110 and the light receiving unit 120 are fixed in a posture in which the optical axis is inclined with respect to the mounting surface 142. As a result, a measurement region by the measurement light is formed above the mounting portion 140. Further, the optical systems such as the light projecting unit 110 and the light receiving unit 120 are held in a posture of looking down at the measurement region obliquely downward.

The support portion 700 connects the pedestal portion 600 and the measuring portion 100. The measuring unit 100 is held so as to be located above the mounting unit 140 via the support unit 700. The measuring unit 100 includes a light emitting unit 110 and a light receiving unit 120 as an observation optical system as described above. The measuring unit 100 is held in a posture of looking down from an oblique direction rather than vertically above the mounting surface 142 of the mounting unit 140 provided on the pedestal unit 600. With such an arrangement, there is an advantage that the shapes of the upper surface and the side surface of the object to be measured can be easily obtained by one measurement. In particular, in order to acquire information in the height direction, information on the side surface of the measurement object having a height difference is useful. On the other hand, it is difficult to grasp the overall shape of the object to be measured only from the side surface. Therefore, the measuring unit is in a posture that allows the object to be measured to be captured from an obliquely upward viewpoint so that both the upper surface, which makes it easy to grasp the overall outer shape, and the side surface, which makes it easy to obtain height information, can be obtained at once. It is beneficial to hold the 100 in an inclined position with respect to the mounting surface 142. In the example shown in the side view of FIG. 6, the optical axes of the light projecting unit 110 and the light receiving unit 120 of the measuring unit 100 are held in an inclined posture so as to form an angle of about 45 ° with respect to the mounting surface 142 of the XYθ stage. doing. In this way, the measuring unit 100 is connected to the pedestal unit 600 by the support unit 700 in a state where the bird's-eye view angle of 45 ° is kept constant. As a result, the measuring unit 100 can always see the mounting surface 142 at a constant angle and a constant position, and the positional relationship between the three axes of XYθ, which are the driving axes of the mounting surface 142, and the observation optical system is kept constant. Dripping.

The light receiving unit 120 may include a plurality of optical systems having different magnifications. An example of this is shown in FIG. In this example, the light receiving unit 120 includes a first optical system having a first magnification and a second optical system having a second magnification higher than the first magnification. As described above, by providing the optical systems having different magnifications, the field of view can be switched according to the size of the measurement object WK placed on the mounting surface 142. In this example, the light receiving element includes a first light receiving element 121b optically coupled to the first optical system and a second light receiving element 121c optically coupled to the second optical system. The first optical system and the first light receiving element 121b may be collectively referred to as the first camera 121B, and the second optical system and the second light receiving element 121c may be collectively referred to as the second camera 121C. By preparing a plurality of light receiving elements in this way and configuring each optical system to take an image with an individual light receiving element, it is possible to perform the image receiving processing received by each optical system in parallel, and to speed up the processing. Simplification of optical coupling is realized. However, a common light receiving element may be optically connected to a plurality of optical systems.

The first optical system and the second optical system are arranged so that their optical axes are parallel to each other. The first optical axis LA1 of the first optical system and the second optical axis LA2 of the second optical system are inclined at about 45 ° with respect to the mounting surface 142, respectively. Here, the high-magnification second optical system, that is, the second camera 121C is arranged vertically side by side in the fixed portion 125 so as to be below the first camera 121B which is the first optical system. With such an arrangement, the movement of the viewpoint when switching from the first optical system to the second optical system becomes the front side of the measurement object WK, and there is an advantage that the change in the visual field can be relatively easily grasped by the user. Is obtained. More precisely, in the first optical system having a wide field of view (low magnification), even if the measurement object WK placed on the mounting surface is large, the second optical system having a narrow field of view (high magnification) In the above case, even if the measurement object WK placed on the mounting surface is small, it is possible to capture the entire measurement object WK when the entire circumference is rotated.
(XYθ stage)

Next, a configuration example of the pedestal portion 600 will be described with reference to FIGS. 7 to 9. In the example of FIG. 7, in the XYθ stage, the XY stage, which is the translational stage 141, is placed on the θ stage, which is the rotation stage 143 fixed on the pedestal portion 600. The rotation axis of the rotation stage 143 is arranged so as to intersect the optical axes of the first optical system and the second optical system at an angle of 45 °, respectively. As shown in the plan views of FIGS. 8 and 9, the translational stage 141 mounted on the rotary stage 143 is configured to rotate together with the XY drive shaft as the rotary stage 143 rotates. FIG. 8 shows the X-axis and the Y-axis for moving the translational stage 141, and FIG. 9 shows the θ direction for rotating the rotation stage 143. By configuring the translational stage 141 on the rotating stage 143 in this way, the optical axis of the measuring unit 100 and the rotating shaft of the rotating stage 143 maintain a mechanically fastened constant relationship. It becomes easy. Further, if necessary, the stage drive axis in the coordinate system in the observation space of the measurement unit 100 can be grasped by calibrating the moving direction of the translational stage 141 and the rotation direction of the stage rotation axis.
(Wide range measurement function by combining rotary stage 143 and translation stage 141)

The three-dimensional shape measuring device 500 according to the present embodiment measures the entire measurement object by synthesizing a plurality of measurement data acquired by changing the field of view even when the measurement object is too large to fit in the measurement field of view. It has a wide range measurement function that enables it. Specifically, the three-dimensional shape measuring device 500 includes a translation stage 141 and a rotation stage 143. Measured by moving the mounting surface 142 in the plane to which the mounting surface 142 belongs, in the present embodiment, in the XY plane, with reference to a predetermined reference position included in the mounting surface, by the translation stage 141. The region can be changed to an arbitrary position, and a desired portion can be measured with high accuracy, including the shapes of both ends protruding from the object to be measured. Then, the rotation stage 143 rotates the mounting surface 142 around the rotation axis included in the mounting surface 142 in, for example, the θ direction, and the measurement object WK rotates accordingly, so that the measurement object WK is rotated from another direction. Measurement becomes possible. In this three-dimensional shape measuring apparatus 500, a wide range measurement function in which the rotating stage 143 and the translation stage 141 are combined will be described with reference to the schematic plan views of FIGS. 10A to 10E and the image views of FIGS. 11A to 11I.

First, as shown in FIG. 10B, the translational stage 141 is moved to the left of the measurement area from the state of FIG. 10A so that the right side of the measurement object WK1 is contained in the measurement area MR1. The observation image OI3 obtained at this position is as shown in FIG. 11A.

Then, the three-dimensional measurement is executed at this position, and the single-field measurement data SI3 shown in FIG. 11B is acquired. As described above, the single-field measurement data SI3 may also be displayed on the display unit 400 as shown in FIG. 11B, or may be hidden.

Next, as shown in FIG. 10C, the translational stage 141 is moved from the state of FIG. 10B to the right of the measurement area so that the left side of the measurement object WK1 is contained in the measurement area MR2. The observation image OI4 obtained at this position is as shown in FIG. 11C. Then, the three-dimensional measurement is executed at this position, and the single-field measurement data SI4 shown in FIG. 11D is acquired.

Further, after rotating the rotation stage 143 by 180 ° so that the back side of the measurement object can be seen, the translation stage 141 is moved to the left again, and the right side of the measurement object WK1 is measured as shown in FIG. 10D. It is in a state of being contained in the area MR3. The observation image OI5 obtained at this position looks like the single-field measurement data SI5 shown in FIG. 11E. Then, the three-dimensional measurement is executed at this position, and the single-field measurement data SI5 shown in FIG. 11F is obtained.

Next, as shown in FIG. 10E from the state of FIG. 10D, the translational stage 141 is moved to the right so that the left side of the measurement object WK1 is contained in the measurement area MR4. The observation image OI6 obtained at this position is as shown in FIG. 11G. Then, the three-dimensional measurement is executed at this position, and the single-field measurement data SI6 shown in FIG. 11H is acquired.

Finally, the single-field measurement data SI3, SI4, SI5, and SI6 are automatically arranged on the coordinate system of the measurement space from the movement stroke and the movement direction of the translation stage 141, and the respective data, that is, FIGS. 11B and 11D. , 11F and 11H are combined to generate the composite image CI2 shown in FIG. 11I and displayed on the display unit 400. In this example, the composite image CI2 is a collection of point cloud data, and the user can drag and rotate the composite image CI2 from the screen to check the shape data of the obtained measurement object from a desired viewpoint. In this way, even if the large measurement object WK1 does not fit in the measurement area, the entire tertiary of the measurement object WK1 can be obtained by synthesizing the single-field measurement data SI3 and SI4 obtained by multiple imaging. The original shape can be measured.

In the above example, the translation stage 141 has been moved in the left-right direction (X direction) in the drawing, but the translation stage 141 may be moved in the up-down direction (Y direction), or a combination of these may be used diagonally. You may move it in the direction. Similarly, the rotation angle of the rotation stage 143 is not limited to 180 ° and can be adjusted to any angle such as 90 ° or 45 °. The moving direction of the translational stage 141 can be appropriately adjusted according to the longitudinal direction of the object to be measured, how to place the object on the mounting surface 142, the complexity of the shape of the object to be measured, and the like.

As described above, the wide range measurement can be realized in any line-of-sight direction in the state where the rotation stage 143 is rotated. By correctly recognizing the moving direction of the translation stage 141, even when the rotation stage 143 is rotated, for example, in order to acquire the right side of the measurement object WK1 as shown in FIG. 11A, the translation stage 141 is moved to the left side of the screen. As shown in FIG. 11C, in order to acquire the left side of the measurement object WK1, the translational stage 141 may be translated to the right of the screen. Further, such control of the moving direction of the mounting surface 142 is performed by the movement control unit 144. The movement control unit 144 holds the moving direction of the mounting surface 142 and the position of the moved mounting surface 142, that is, the measurement area of the measurement object WK1 placed on the mounting surface 142 in association with each other. In addition, how each single-field measurement data acquired in each measurement area should be arranged in the measurement space is also coordinate-transformed based on the movement amount of the translation stage 141, the XY movement direction, and the rotation amount of θ. Since it can be calculated, automatic alignment and composition processing can be realized.

In the above example, data acquisition in each line-of-sight direction has been described. However, the present invention is not limited to this configuration, and for example, the rotation stage 143 may be rotated to a plurality of angles so that the wide range measurement results acquired at each angle are superimposed. In this case, measurement data can be acquired and superimposed on a large and three-dimensional object to be measured from any direction of 360 °, and full 3D data from all directions can be measured.

Further, in the configuration in which the rotation stage 143 and the translation stage 141 coexist, when the rotation stage 143 is rotated, it is preferable to return the translation stage 141 to a predetermined reference position and then rotate the rotation stage 143. As a result, it is possible to avoid a state in which the radius of gyration of the mounting portion 140 on which the measurement object is placed becomes large, and to avoid a situation in which the measurement object unintentionally collides with another member.
(Reference position)

The reference position is a predetermined position included in the mounting surface of the mounting portion. This reference position is typically the reference position of the coordinate axes, for example, the origin O (0,0) of the XY plane including the mounting surface 142 shown in FIG. As a result, the mounting surface is moved starting from the reference position. However, the reference position is not necessarily limited to the origin of the coordinate axes, and may be a position offset from the origin. In addition, when it is described as "returning to the reference position" in this specification, it does not mean that it returns to the reference position accurately, but it means that it is sufficient to return it to the vicinity of the reference position.
(Detection of the amount of protrusion of the object to be measured)

However, as described above, the rotation stage 143 and the translation stage 141 coexist in order to minimize the interference between the measurement object WK and the three-dimensional shape measurement device 500, and the translation stage 141 is returned to the predetermined reference position. Even if a configuration in which the rotation stage 143 is rotated is adopted, it may be difficult to avoid interference during rotation depending on the size of the measurement object WK.

Therefore, the conditions under which interference between the measurement object WK and the three-dimensional shape measuring device 500 may occur will be described with reference to FIGS. 12A to 13. 12A to 12C show the posture in which the mounting portion 140 is in the reference position shown in FIG. In each figure, the maximum value of the amount of protrusion of the measurement object mounted on the mounting portion is L1, and the minimum value of the separation distance between the position OP of the outer peripheral end OL of the mounting surface 142 and the support portion 702 of the support portion 700 is set. Let it be L2. Here, the position OP of the outer peripheral edge OL is the position where the diameter is the largest among the outer peripheral edge OL of the mounting surface 142 when the mounting portion 140 is viewed in a plan view as shown in FIG. 12A or the like. It is stipulated as. Further, the minimum separation distance L2 is defined as the position in which the OP is closest to the support column 702 when the rotation stage 143 is rotated while the mounting portion 140 is in the reference position. The distance to the opposite surface of. When the mounting surface 142 is circular as shown in FIG. 12A or the like, the OP is at an arbitrary position of the outer peripheral end OL, and when the mounting surface 142a is rectangular as shown in FIG. 13, the OP is in the longitudinal direction. It becomes a corner.

As shown in FIG. 12A, when the measurement object WK2 is arranged in the mounting surface 142 so as not to protrude from the mounting surface 142, the measurement object WK2 collides even if the rotation stage 143 is rotated. There is no fear and it can rotate freely. However, as shown in FIGS. 12B and 12C, when the ends of the measurement objects WK3 and 4 protrude from the outer peripheral end OL of the mounting surface 142, the rotation stage 143 may or may not be rotated. It is divided into cases. As shown in FIG. 12B, when the relationship between L1 and L2 is L2> L1, the measurement target WK3 can rotate the rotary stage 143 without interfering with the support column 702. On the other hand, as shown in FIG. 12C, when L1> L2, the measurement target WK4 interferes with or collides with the support column portion 702, so that the rotation stage 143 cannot be freely rotated. That is, whether or not the rotation stage 143 can be rotated is determined according to the amount of protrusion of the measurement object WK from the mounting portion 140. Therefore, in the present embodiment, this pop-out amount is detected. By detecting the amount of protrusion from the mounting portion 140 in advance of the rotational movement in this way, it is possible to control the rotational movement of the rotary stage 143 while making it possible to avoid interference and collision.

In order to detect the amount of protrusion of the measurement object WK, that is, the end portion protruding from the mounting portion 140 of the measurement object WK, it is necessary to move the protruding end portion into the measurement area. Specifically, the translational stage 141 is measured in a direction (horizontal direction in the drawing) in which the mounting portion 140 approaches and separates from the support portion 700 in the plan view of the mounting surface 142. Move toward the center side of. As a result, the end of the measurement target WK can be moved in the direction of being within the measurement region, so that the end of the measurement target WK can be detected. In this way, by grasping the amount of protrusion of the end portion of the measurement object WK protruding from the mounting portion 140, it is possible to avoid a collision due to the movement of the mounting portion 140.

Here, the relationship between the measurement area and the moving direction of the mounting portion 140 will be described with reference to FIGS. 14A to 14B. In these figures, the measurement region MR5 is shown in an inverted trapezoidal shape. In the mounting mode of the measurement target WK5 illustrated in FIG. 14A, the broken line portion ND of the measurement target WK5 protruding from the outer peripheral end OL of the mounting surface 142 included in the translation stage 141 is outside the measurement region MR5. The outer shape cannot be detected. Therefore, as shown in FIG. 14B, if the translational stage 141 is translated to the left by a distance D, the end portion of the measurement object WK5 can be moved substantially inward of the measurement region MR5.

In the examples of FIGS. 14A to 14B, the mounting portion 140 is in the posture of the reference position, and the outer peripheral end OL of the mounting surface 142 is configured to be substantially within the measurement area. With such a configuration, if the object to be measured fits in the mounting surface 142, the outer shape of the end portion thereof can be grasped at the reference position.

Further, it is preferable to translate the translation stage 141 by a distance larger than the minimum separation distance L2. That is, the translational stage 141 is translated so as to satisfy the movement distance D> the minimum separation distance L2 of the translational stage 141. If the translation stage 141 is to be moved to the support column 702 side (downward in the figure) in the state of FIG. 14A, the translation stage 141 collides with the support column 702 when it is moved by L2 or more. In other words, the amount of movement of the translation stage 141 is constrained by L2. On the other hand, the movement of the translational stage 141 in the lateral direction is not restricted from the viewpoint of avoiding collision with the support column 702. Moreover, by moving the translational stage 141 significantly, there is a high possibility that the end portion of the measurement object WK5 placed on the mounting surface 142 can be moved into the measurement area MR5. If the amount of movement of the translational stage 141 in the lateral direction is restricted to L2 or less, the end portion of the measurement object WK5 cannot be accommodated in the measurement area MR5, and collision avoidance cannot be achieved. Further, by repeating the movement of L2 or less a plurality of times, even if the end portion of the measurement object WK5 is housed in the measurement area MR5, the movement is required a plurality of times and the measurement time becomes long. Therefore, by making the amount of lateral movement that does not cause a collision with the support column 702 larger than that of L2, the translational stage 141 can be moved significantly, and even if it is a long measurement object WK5, its end portion. Is stored in the measurement area MR5, and the outer shape of the measurement object WK5 can be grasped to avoid a collision.

In the above example, a configuration example in which the translational stage 141 has a circular shape has been described. By making the translation stage 141 circular, the operation of the translation stage 141 can be made smooth, and the diameter is almost uniform, so that the user can easily grasp the maximum diameter of the translation stage 141. However, the translational stage of the present invention is not limited to a circular shape, and various shapes such as a polygonal shape and an elliptical shape can be adopted. For example, the translation stages 141a to 141c according to the modified examples shown in FIGS. 15A to 15C have a rectangular shape, an octagonal shape, and an elliptical shape, respectively. By adopting such a shape, the maximum diameter R can be increased in only one direction without increasing the size of the entire translation stage. Further, when the translational stage has a circular shape, it may be difficult to determine whether or not the stage is in the reference position because the outer shape is constant when viewed from any direction. On the other hand, if the translation stage has a polygonal shape such as a rectangular shape or an octagonal shape or an elliptical shape, the outer shape changes, so that it is easy to determine whether or not the stage is in the reference position.

Further, in the above example, a configuration example of the mounting portion 140 in which the translational stage 141 is arranged on the upper surface of the rotating stage 143 has been described. With such an arrangement, the rotary stage 143 can be rotatably fixed to the pedestal portion, and the translational stage 141 can be rotated by the rotary stage 143 together with the measurement object on the upper surface thereof. By rotating the measurement object and the translation stage 141 together in this way, the positional relationship between the measurement object and the translation stage 141 can be maintained constant as long as the placement posture of the measurement object is not changed. As a result, the three-dimensional measurement from a plurality of different viewpoints obtained by rotating the rotation stage 143 is always performed within the range of the same measurement object, and the same points on the measurement object are averaged with data from the plurality of viewpoints. It is possible to perform stable measurement over the entire object to be measured, and the measurement accuracy is improved.

However, the present invention does not limit the mounting portion 140 to such a configuration, and for example, as shown in the three-dimensional shape measuring device 500B according to the modified example shown in FIG. 16, the rotating stage 143 is arranged on the upper surface of the translation stage 141. It may be configured. Even with such an arrangement of the mounting portion 140, it is possible to acquire omnidirectional full 3D data of the measurement object that also protrudes from the field of view by the same measurement and superposition.
(How to detect the edge)

As a method of detecting the end of the object to be measured by the end detection unit 265, a method of using three-dimensional data by a three-dimensional shape measuring device can be considered. For example, there are methods such as edge detection by two-dimensional imaging of three-dimensional data and edge detection by a mesh image. Hereinafter, details will be given in order.
(End detection by 2D image)

In the edge detection by two-dimensional imaging of three-dimensional data, a two-dimensional top view map image is generated from the three-dimensional point cloud data. The procedure for generating the top view map image is as described above. From the obtained two-dimensional top view map image, contour pixels of the measurement object are extracted, and the end portion of the measurement object is detected. An example of the contour pixels of the extracted measurement object is shown in FIG.
(End detection by mesh image)

In the edge detection using the mesh image, a mesh image is generated from the three-dimensional point cloud data by Delaunay triangle division or the like. Then, the mesh image is taken from above, the contour line is obtained, and the end portion of the measurement object is detected. As an example, FIG. 18 shows the generated mesh image, and FIG. 19 shows a state in which the mesh image is taken from above and the contour lines where the edges of the measurement object are detected are overlapped.

In the two-dimensionalization and the mesh image, the mesh image may be generated first. In this case, the amount of calculation becomes slightly large. Here, the reason why the data is made two-dimensional instead of the three-dimensional data is that the cross-sectional view of the mounting portion 140 is almost constant regardless of the height direction (Z direction). If the mounting portion 140 is tilted and the position of the stand changes depending on the Z position, it is necessary to detect the end portion in three dimensions.

Further, as another method of detecting the end portion, a method of detecting and determining the end portion of the object to be measured by using the two-dimensional image obtained from the camera as it is, or a method of separately providing a simple non-contact sensor to detect the end portion is provided. A method of detecting a part can also be mentioned.
(Notification to user)

As a response when the possibility of collision is detected in advance by the end detection unit 265 or the regulation judgment unit 266, the data of the measurement position avoided by the collision, that is, the data of the measurement position avoided by the collision without explicitly notifying the user. The data of the portion where the processing is skipped may be lost. Alternatively, it can be explicitly notified to the user. For example, after the measurement, the measurement position avoiding the collision is displayed on the display unit 400 as a result report. Alternatively, it is notified that a collision has been detected in advance after or during the measurement. At this time, it may be requested to determine whether to continue the measurement process or interrupt it there. Alternatively, when the pre-detection is performed before the measurement, a message such as "Because the pre-collision is detected, some measurements are avoided" is displayed on the display unit 400 after the pre-detection or before the start of the measurement.

The three-dimensional shape measuring device and the three-dimensional shape measuring method of the present invention are based on the three-dimensional shape measuring device or digitizer that measures the height of the object to be measured by using a principle such as triangular distance measurement, or the inspection results thereof. Therefore, it can be suitably used as an inspection device for determining whether a product is a good product or a defective product.

1 ... Control PC
2 ... Monitor 3 ... Keyboard 4 ... Input device 100 ... Measurement unit 101 ... Main body case 102 ... Light-shielding cover 110 ... Light projection unit; 110A ... First measurement light projection unit; 110B ... Second measurement light projection unit 111 ... Measurement Light source 112 ... Pattern generation units 113 to 115, 122, 123 ... Lens 120 ... Light receiving unit 121 ... Camera 121B ... First camera; 121C ... Second camera 121a ... Imaging element; 121b ... First light receiving element; 121c ... Second light receiving element Element 125 ... Fixed unit 130 ... Illumination light output unit 140 ... Mounting units 141, 141a to 141c ... Translation stage 142, 142a ... Mounting surface 143 ... Rotation stage 144 ... Movement control unit 150 ... Measurement control unit 200 ... Controller 210 ... CPU
211 ... Point cloud data synthesis unit 216 ... Image inspection unit; 216b ... Measurement unit 220 ... ROM
228 ... Height image acquisition unit 230 ... Working memory 240 ... Storage device 250 ... Operation unit 260 ... Point group data generation unit 261 ... Top view map image generation unit 262 ... Mesh image generation unit 264 ... Measurement area setting unit 265 ... Edge Unit detection unit 266 ... Regulation judgment unit 300 ... Light source unit 310 ... Control board 320 ... Observation illumination light source 400 ... Display unit 500, 500B ... Three-dimensional shape measuring device 500A ... Three-dimensional shape measuring device main body 600 ... Pedestal unit 700 ... Support Part 702 ... Support column 1000 ... Three-dimensional shape measurement system WK, WK1 to WK5 ... Measurement object ML ... Measurement light; ML1 ... First measurement light; ML2 ... Second measurement light LA1 ... First optical axis; LA2 ... Second Optical axis MR1, MR2, MR3, MR4, MR5 ... Measurement area OI3 to OI6 ... Observation image SI3, SI4, SI5, SI6 ... Single field measurement data CI2 ... Composite image IL ... Illumination light ND ... Undetectable end of measurement object L1 ... Maximum value of the amount of protrusion of the object to be measured L2 ... Minimum separation distance O ... Origin D of the XY plane ... Movement distance of the translation stage OL ... Outer edge OP ... One point at the outer edge

Claims (11)

A three-dimensional shape measuring device that measures the three-dimensional shape of an object to be measured.
A rotating stage that rotates the mounting surface on which the object to be measured is placed around the rotation axis included in the mounting surface, and
A mounting portion including a translation stage for translating the above-described mounting surface in the plane to which the mounting surface belongs, based on a predetermined reference position included in the mounting surface.
A light projecting unit that irradiates a measurement object placed on the above-mentioned storage unit with measurement light having a predetermined pattern,
A light receiving unit that receives the measurement light that is irradiated by the light projecting unit and is reflected by the measurement object and outputs a light receiving signal that indicates the amount of received light.
The pedestal part that supports the above-mentioned placement part and
A support portion that is connected to the pedestal portion and that fixedly supports the light projecting portion and the light receiving portion so that a measurement region by measurement light is formed above the above-mentioned placement portion.
A point cloud data generation unit that generates point cloud data representing the three-dimensional shape of the object to be measured based on the light reception signal output by the light receiving unit supported by the support unit.
In the posture in which the translation stage is in the reference position, the translation stage is translated by the outer peripheral end of the above-mentioned placement portion and the surface facing the outer peripheral end and the support portion by a minimum distance or more. A movement control unit that controls the placement unit and
A three-dimensional shape measuring device including. The three-dimensional shape measuring device according to claim 1.
The movement control unit is configured to move the translation stage so that the end portion of the measurement object mounted on the previously described placement portion protruding from the previously described placement portion is included in the measurement area. A three-dimensional shape measuring device. The three-dimensional shape measuring device according to claim 1 or 2.
The movement control unit sets the translational stage on the pre-described mounting surface so that the end portion of the measurement object mounted on the pre-described mounting portion that protrudes from the pre-described mounting portion is included in the measurement area. In a plan view, a three-dimensional structure is such that the above-mentioned placement portion is in a direction (* X direction) that intersects the depth direction that approaches and separates from the support portion, and is configured to move toward the center side of the measurement region. Shape measuring device. The end of the three-dimensional shape measuring device according to any one of claims 1 to 3, further detecting an end of a measurement object mounted on the above-mentioned placement portion, which protrudes from the above-mentioned placement portion. A three-dimensional shape measuring device including a unit detection unit. The three-dimensional shape measuring device according to claim 4.
The end detection unit is a three-dimensional shape measuring device configured to execute an end detection operation in a state where the movement control unit translates the translation stage from the reference position by a distance equal to or greater than the minimum separation distance. .. The three-dimensional shape measuring device according to claim 4 or 5.
The end portion detection unit is a three-dimensional shape measuring device configured to detect the end portion based on the point cloud data generated by the point cloud data generation unit. The three-dimensional shape measuring device according to any one of claims 4 to 6, further comprising.
Whether to regulate the rotational movement of the rotating stage or the translational movement of the translation stage in the direction in which the end portion approaches the support portion, based on whether or not the end portion can be detected by the end portion detecting portion or the detection position. A three-dimensional shape measuring device provided with a regulatory judgment unit that determines whether or not it is present. The three-dimensional shape measuring device according to claim 7.
Based on the end detection result by the end detection unit, the regulation determination unit changes the movement direction and / or movement amount of the above-mentioned placement portion so that the end portion of the measurement object does not approach the support portion. A three-dimensional shape measuring device instructing the movement control unit to do so. The three-dimensional shape measuring device according to claim 7 or 8.
The regulation determination unit is configured to output an image, characters, or voice notifying that the end of the object to be measured approaches the support based on the result of detecting the end by the end detection unit. Three-dimensional shape measuring device. The three-dimensional shape measuring device according to any one of claims 1 to 9.
The above-mentioned placing portion is a three-dimensional shape measuring device in which the translational stage is provided above the rotating stage rotatably supported by the pedestal portion. The three-dimensional shape measuring device according to any one of claims 1 to 10.
The translational stage is a three-dimensional shape measuring device having a circular shape.