Contour Shape Measurement Apparatus and Method

Abstract

This invention relates to a contour shape measuring device, which measures the contour shape of the periphery of a measurement object based on a shadow image obtained by projecting parallel light from the tangential direction of the outer periphery onto the periphery of the measurement object via a camera. The device is characterized by controlling first to third support members for supporting the measurement object in a manner that ensures the parallel light is parallel to the surface of the measurement object along the projection direction. Each of the first to third support members is equipped with a first to third moving mechanism that moves the first to third support positions of the measurement object vertically; the aforementioned control individually controls each of the first to third moving mechanisms.

Description

Technical Field

[0001] This invention relates to a contour shape measuring device and a contour shape measuring method for measuring the contour shape of a circular plate-shaped object. Prior Technology

[0002] In a device for determining the outline shape of a circular object, a shadow image is generated by illuminating parallel light tangentially to the periphery of the object using a camera, thereby creating the shadow (image) of the periphery. For accurate shape determination, the parallel light and the inner and outer surfaces of the object must be set to be parallel to each other. For example, Japanese Patent No. 4897658 (D1) discloses a technique that adjusts the slope of the parallel light (the slope of the projection direction of the parallel light) for the object placed on a stage. The shape measuring device disclosed in D1 includes: a light projection means for projecting parallel light onto the end of a disc-shaped object to be measured; an imaging means for capturing a projected image of the end of the object to be measured from a direction opposite to the light projection direction of the light projection means; an optical system holding member for holding the light projection means and the imaging means; an optical system driving means for driving the optical system holding member to change the slope of the light projection direction relative to the surface of the object to be measured; a slope index detection means for detecting an index of the degree of tilt of the object to be measured relative to the light projection direction; and a first slope adjustment means for controlling the optical system driving means according to the detection result of the tilt index. This adjusts the slope of the aforementioned projection direction relative to the surface of the aforementioned object to be measured; the aforementioned slope index detection means is: a displacement detection means, which, while the aforementioned optical system holding member is held, detects the position of the surface of the aforementioned object to be measured in a direction orthogonal to the aforementioned projection direction at a plurality of observation positions along the aforementioned projection direction; the aforementioned first slope adjustment means adjusts the slope of the aforementioned projection direction in a direction that makes the relationship between the position of the aforementioned object to be measured in a direction orthogonal to the aforementioned projection direction at the plurality of observation positions approach the positional relationship of the aforementioned object to be measured in a predetermined target; the shape of the end face of the aforementioned object to be measured is determined based on the aforementioned projection image obtained by the aforementioned imaging means.

[0003] However, the shape measuring device disclosed in D1 adjusts the slope of the projection direction relative to the surface of the object by rotating the optical system holding member that holds the projection and imaging means. Therefore, the installation accuracy of the projection and imaging means when installing the optical system holding member before adjusting the slope of the projection direction will affect the measurement accuracy. Furthermore, in the shape measuring device disclosed in D1, the first slope adjustment means can only adjust one degree of freedom in the direction orthogonal to the projection direction, and the slope of the projection direction is adjusted after the projection and imaging means are installed on the optical system holding member. Therefore, in cases where the optical axis of the projection and imaging means cannot be adjusted relative to the object by the aforementioned first slope adjustment means, the projection and imaging means must be reinstalled on the optical system holding member. Summary of the Invention

[0004] [The problem the invention aims to solve] The present invention was made in light of the aforementioned circumstances, and its purpose is to provide a contour shape measuring device and a contour shape measuring method, which can more appropriately adjust the posture of the measuring object. [Technical means to solve the problem]

[0005] One aspect of the present invention, a contour shape measuring device and a contour shape measuring method, measures the contour shape of the periphery of a measuring object based on a shadow image obtained by projecting parallel light from the tangential direction of the outer periphery onto the periphery of the measuring object using a camera. The characteristic feature is that the first to third support members used to support the measuring object are controlled in such a way that the parallel light is parallel to the surface of the measuring object along the projection direction. The aforementioned first to third support members are equipped with first to third moving mechanisms that move the first to third support positions of the measuring object vertically, and the aforementioned control individually controls the first to third moving mechanisms. [Effects of the Invention]

[0006] The objects, features and advantages of the foregoing invention and other inventions will become apparent from the following detailed description and accompanying drawings. Simple Explanation of the Diagram

[0007] [Figure 1] is a block diagram showing the electrical configuration of the contour shape measuring device according to the embodiment. [Figure 2] is a schematic top view of the aforementioned contour shape measuring device. [Figure 3] is a schematic side view of the aforementioned contour shape measuring device when viewed from direction A as shown in Figure 2. [Figure 4] is a schematic side view of the aforementioned contour shape measuring device when viewed from direction B as shown in Figure 2. [Figure 5] is a diagram used to illustrate the supporting components. [Figure 6] is an example used to illustrate the multiple parameters of the contour shape. [Figure 7] is a diagram illustrating the calibration of the support member of the aforementioned contour shape measuring device. [Figure 8] is a flowchart showing the operation of the aforementioned contour shape measuring device for calibration. [Figure 9] is a flowchart showing the operation of the aforementioned contour shape measuring device for correcting the support member shown in Figure 8. [Figure 10] is a flowchart showing the operation of the aforementioned contour shape measuring device for correcting the support member with respect to the deformation shape. Implementation

[0008] Hereinafter, one or more embodiments of the present invention will be described with reference to the accompanying drawings. However, the scope of the invention is not limited to the disclosed embodiments. Furthermore, configurations with the same symbols in each figure represent the same configuration, and their descriptions are appropriately omitted. In this specification, reference numerals with omitted additional text are used to indicate general terms, while reference numerals with additional text are used to indicate specific configurations.

[0009] The contour shape measuring device of the embodiment is an apparatus that projects parallel light from the tangential direction of the outer periphery of a circular plate-shaped measuring object, captures the shadow of the periphery generated by the parallel light, and measures the contour shape of the periphery based on the captured image of the shadow of the periphery. This contour shape measuring device includes: at least three first to third support members for supporting the measuring object from below at at least three points; and a control unit that controls the first to third support members in such a way that the parallel light is parallel to the surface of the measuring object along the projection direction, based on the image of the shadow of the periphery. Each of the first to third support members has a first to third moving mechanism for moving the first to third support positions of the measuring object vertically, and the control unit individually controls the first to third moving mechanisms. The contour shape measuring device and the contour shape measuring method installed thereon will be described in more detail below.

[0010] Figure 1 is a block diagram showing the electrical configuration of the contour shape measuring device according to the embodiment. Figure 2 is a schematic top view of the aforementioned contour shape measuring device. Figure 3 is a schematic side view of the aforementioned contour shape measuring device when viewed from direction A shown in Figure 2. Figure 4 is a schematic side view of the aforementioned contour shape measuring device when viewed from direction B shown in Figure 2. Figure 5 is a diagram illustrating the support member. Figure 5A is an overall view, and Figure 5B is a diagram illustrating the support claw member.

[0011] The contour shape measuring device 1000 of the embodiment is shown in Figures 1 to 5, for example, including a light projection unit 1, an image capturing unit 2, an optical system holding unit 3, first to third support members 4-1 to 4-3, a control processing unit 5, an input unit 6, an output unit 7, an interface unit (IF unit) 8, and a memory unit 9.

[0012] The projection unit 1 is connected to the control processing unit 5 and, under the control of the control processing unit 5, projects parallel light from the outer periphery of the circular measuring object WK in the tangential direction (projection direction) DR. The measuring object WK can be any circular shape, such as wafers used in semiconductor manufacturing (e.g., silicon wafers) or aluminum or glass disk substrates used in hard drives. The projection unit 1 includes, for example, a light source 11 connected to the control processing unit 5, which emits illumination light under the control of the control processing unit 5; and an illumination optical system 12 that makes the illumination light emitted by the light source 11 parallel light and provides illumination. The light source 11 includes, for example, a white light-emitting diode (white LED) and a pinhole plate with pinholes of approximately 300 μm to 400 μm, and emits white light from the aforementioned white LED through the aforementioned pinholes as illumination light. The illumination optical system 12 includes, for example, a collimating lens 121 that makes the illumination light emitted by the light source 11 parallel; and first and second shielding plates 122 and 123 of the same shape with rectangular openings. This illumination optical system 12 makes the illumination light emitted by the light source 11 parallel by the collimating lens 121, and emits point-like parallel light through the rectangular openings of the first and second shielding plates 122 and 123. When a measurement object WK is disposed there, the aforementioned parallel light is projected onto the periphery of the measurement object WK. The first and second shielding plates 122 and 123 block light outside the imaging range of the imaging unit 2. In this example, there are two shielding plates, but one, three or more, or even no shielding plates are required.

[0013] The camera unit 2 is connected to the control processing unit 5 and, under the control of the control processing unit 5, captures the shadow (image) of the peripheral portion of the measurement object WK generated by the aforementioned parallel light. The camera unit 2 may include, for example, a light-receiving optical system 21 and a two-dimensional image sensor 22. The light-receiving optical system 21 is a telecentric lens comprising a first lens 211, an aperture 212, and a second lens 213, which forms the image (shadow) of the peripheral portion of the measurement object WK generated by the aforementioned parallel light onto the two-dimensional image sensor. The two-dimensional image sensor 22 is connected to the control processing unit 5 and may be, for example, a CCD or CMOS type two-dimensional image sensor. Under the control of the control processing unit 5, it captures the image (shadow) of the peripheral portion of the measurement object WK formed by the light-receiving optical system 21 and outputs the data (raw data) generated by the aforementioned capture to the control processing unit 5.

[0014] The optical system holding unit 3 is a device that holds the light-projecting unit 1 and the camera unit 2 in a fixed positional relationship, and is connected to the control processing unit 5. It is a device that adjusts the slope of the optical axis AX (the slope of the light projection direction DR) of the light-projecting unit 1 and the camera unit 2 according to the control of the control processing unit 5.

[0015] The aforementioned slope of the optical axis AX (slope of the projection direction DR) represents the slope of the optical axis AX relative to the surface (surface or interior) of the object being measured, when the periphery of the object being measured, WK, is located between the projection unit 1 and the imaging unit 2. It is expressed unambiguously by the angle formed between the surface (surface or interior) of the object being measured, WK, and the optical axis AX (projection direction DR). When the parallel light from the projection unit 1 is parallel to the surface of the object being measured, WK, along the projection direction DR, the aforementioned slope of the optical axis AX (slope of the projection direction) is 0 degrees.

[0016] The optical system holding part 3 includes, for example, a holding member 31, a support shaft 32, a shaft support member 33, a base member 34, and a slope adjustment mechanism (first slope adjustment mechanism) 35.

[0017] The retaining member 31 is a component that holds the projection unit 1 and the imaging unit 2. The retaining member 31 is, for example, a metal plate (rigid body) extending in a single direction, and is bent at approximately 90 degrees to form a rectangular retaining plate portion 311 and a rectangular upright plate portion 312, thereby forming an approximately L-shaped cross-section. In the retaining plate portion 311, the light source 11, collimating lens 121, first mask plate 122, second mask plate 123, first lens 211, aperture 212, second lens 213, and two-dimensional image sensor 22 are sequentially and fixedly arranged so that their optical axes AX are aligned. Therefore, if ideally arranged as designed, the optical axis AX will be aligned with the projection direction DR. The second mask plate 123 and the first lens 211 are arranged at appropriate intervals so that the periphery of the measurement object WK can be positioned. An opening is formed in the upright plate portion 312 at approximately the center position (the intersection of the two diagonals) to allow the support shaft 32 to be inserted.

[0018] The shaft support member 33 and the pedestal member 34 are both plate-shaped members. The shaft support member 33 is fixedly mounted on the pedestal member 34 in a vertical manner. The support shaft 32 is a cylindrical member that protrudes from the shaft support member 33 at a position higher than the center position in the height direction (vertical direction) (the upper position) and is inserted through the opening previously described in the vertical plate portion 312. In this way, the retaining member 31 is supported by the support shaft 32, which is orthogonal to the projection direction DR, and can rotate around the support shaft 32 as the center.

[0019] As shown in Figures 2 to 4, when the XYZ rectangular coordinate system is set, if it is ideally configured as designed, the projection direction DR (optical axis AX) is the X-axis direction (the left-right direction of each plane in Figures 2 to 4), and the aforementioned height direction is the Z-axis direction (the up-down direction of each plane in Figures 3 and 4). The Y-axis direction is orthogonal to the projection direction DR (optical axis AX) and the aforementioned height direction (the up-down direction of the plane in Figure 2). If the contour shape measuring device 1000 is ideally assembled as designed, and the periphery of the measuring object WK is ideally configured between the second shielding plate 123 and the first lens 211, then the surface of the measuring object WK will be parallel to the XY plane.

[0020] The slope adjustment mechanism 35 is connected to the control processing unit 5. Under the control of the control processing unit 5, it rotates the holding member 31 around the support shaft 32, thereby adjusting the slope of the projection direction DR (the slope of the optical axis AX). The slope adjustment mechanism 35 includes, for example: a columnar rod member 351, vertically mounted on the base member 34; a servo motor 352 disposed at the front end of the rod member 351; a worm gear 353 disposed on the rotation shaft of the servo motor 352; and a worm wheel 354 fixedly disposed on the upright plate portion 312 of the holding member 31. The worm gear 353 and the worm wheel 354 are a worm gear that meshes with each other. The servo motor 352 is connected to the control processing unit 5 and rotates under the control of the control processing unit 5, thereby driving the aforementioned worm gear, and thus causing the holding member 31, supported by the support shaft 32, to rotate around the support shaft 32. This changes the slope of the projection direction DR (the slope of the optical axis AX).

[0021] The first to third support members 4-1 to 4-3 are members used to support the measurement object WK from below at three points. The first to third support members 4-1 to 4-3 are arranged such that the first to third support positions supporting the measurement object WK are located at the vertices of a triangle. The first and second support members 4-1 and 4-2 are arranged relatively close to the aforementioned parallel light, and the third support member 4-3 is arranged relatively far away from the aforementioned parallel light. In this embodiment, in order to suppress the deflection of the measurement object WK, the aforementioned triangle is an isosceles triangle with the first line segment connecting the first support position and the second support position shorter than the second line segment connecting the first support position and the third support position (the length of the third line segment connecting the second support position and the third support position is equal to the length of the third line segment).

[0022] The first to third support members 4-1 to 4-3 have the same structure. Therefore, the following description mainly focuses on the first support member 4-1. The symbols for the second and third support members 4-2 and 4-3 are written in parentheses after the symbols for the first support member 4-1, which correspond to the structures of the second and third support members 4-2 and 4-3, in place of the descriptions for the second and third support members 4-2 and 4-3. The descriptions for the second and third support members 4-2 and 4-3 are omitted.

[0023] The first support member 4-1 (4-2, 4-3), as shown in FIG. 5, includes: a first moving mechanism 41-1 (41-2, 41-3) for moving the first support position of the measuring object WK in the vertical direction (Z direction); and a first support claw member 42-1 (42-2, 42-3) having an inclined first support surface TF4-1 (TF-2, TF-3) in a point contact manner with the periphery of the measuring object WK. The first moving mechanism 41-1 (41-2, 41-3) is connected to the first support claw member 42-1 (42-2, 42-3). The first moving mechanism 41-1 (41-2, 41-3) is connected to the control processing unit 5 and moves the first support claw member 42-1 (42-2, 42-3) in the vertical direction according to the control of the control processing unit 5. Therefore, by making point contact with the first support surface TF-1 (TF-2, TF-3) of the first support claw member 42-1 (42-2, 42-3) to support the first support position of the measurement object WK, it will move in the vertical direction. The first moving mechanism 41-1 (41-2, 41-3) is, for example, an electric cylinder (electromagnetic solenoid, electromagnetic actuator) vertically mounted on the base member 34. The aforementioned electric cylinder includes, for example: an electric motor connected to the control processing unit 5, which rotates according to the control of the control processing unit 5; a cylindrical piston rod; and a conversion mechanism that converts the rotational motion of the aforementioned electric motor into the linear motion of the aforementioned piston rod. The first support claw member 42-1 (42-2, 42-3) is a columnar member of angle column or cylinder, one end of which is obliquely cut, thereby having a first support surface TF-1 (TF-2, TF-3) that is an inclined push-pull surface. In the example of the first moving mechanism 41-1 (41-2, 41-3), the front end of the aforementioned electric cylinder piston rod is fixedly configured and connected to the other end of the first support claw member 42-1 (42-2, 42-3).

[0024] As shown in FIG2, the first to third support members 4-1 to 4-3 are arranged such that the first to third support positions are located at the vertices of the triangle (in this embodiment, the aforementioned isosceles triangle), and the first to third support surfaces TF-1 to TF-3 are arranged toward the inner side of the aforementioned triangle (in this embodiment, the aforementioned isosceles triangle) (more specifically, the center of the circumcircle of the aforementioned triangle). The object to be measured, WK, is supported from below by the first to third support surfaces TF-1 to TF-3 of the first to third support claw members 42-1 to 42-3 in a point-contact manner around its periphery. It is positioned between the projection unit 1 and the imaging unit 2 to project the aforementioned parallel light onto the periphery of the object to be measured, thus the holding plate 311 of the holding member 31 has openings at positions corresponding to the placement positions of the first and second support members 4-1 and 4-2, respectively, for the insertion of the first and second moving mechanisms 41-1 and 41-2. Alternatively, the openings for the insertion of the first and second moving mechanisms 41-1 and 41-2 may also be openings for the protrusion and retraction of the first and second support claw members 42-1 and 42-2.

[0025] Furthermore, support member 4 refers to the object WK being measured from below and supported at 4 or more points, and there may be 4 or more of them.

[0026] Input unit 6 is connected to control processing unit 5 and is a machine that inputs various instructions, such as instructions to start calibration or instructions to start measurement, and various data required to operate the contour shape measuring device 1000, such as the name of the measurement object WK. For example, it may be a plurality of input switches, a keyboard, a mouse, etc., with predetermined functions. Output unit 7 is connected to control processing unit 5 and is a machine that outputs instructions or data input from input unit 6 and measurement results, according to the control of control processing unit 5. For example, it may be a display device such as a CRT monitor, an LCD (liquid crystal display) or an organic EL monitor, or a printing device such as a printer.

[0027] Furthermore, the input unit 6 and the output unit 7 can also be constructed using a touch panel. In the case of such a touch panel, the input unit 6 is, for example, a position input device that detects and inputs the operation position using a resistive film or capacitive type, and the output unit 7 is a display device. In this touch panel, the position input device is provided on the display surface of the display device, and the display device displays one or more candidate input contents. When the user touches the display position showing the desired input content, the position input device detects the position and inputs the content displayed at the detected position as the user's operation input to the contour shape measuring device 1000. Because such a touch panel allows users to intuitively understand the input operation, it provides a contour shape measuring device 1000 that is easy for users to use.

[0028] The IF section 8 is connected to the control processing section 5 and operates under the control of the control processing section 5. For example, it can be a circuit for inputting and outputting data with an external machine, such as a serial communication RS-232C interface circuit, a Bluetooth (registered trademark) interface circuit, or a USB interface circuit. Furthermore, the IF section 8 can also be a data communication card or a communication interface circuit conforming to the IEEE 802.11 standard, used for transmitting and receiving communication signals with an external machine.

[0029] The memory unit 9 is electrically connected to the control processing unit 5 and, in accordance with the control of the control processing unit 5, stores various preset programs and various preset data.

[0030] The aforementioned predetermined programs include, for example, a control processing program, which includes, for example, a control program, an image processing program, a first slope control program, a second slope program, and a contour shape processing program. The aforementioned control program controls the functions of each part 11, 22, 6-9 of the contour shape measuring device 1000. The aforementioned image processing program generates image data (shadow image data) representing the shadow of the periphery of the measuring object WK by performing image processing on the data (raw data) output from the two-dimensional image sensor 22 of the self-image unit 2. The aforementioned first slope control program controls the slope adjustment mechanism (first slope adjustment mechanism) 35 so that the parallel light from the projection unit 1 is parallel to the surface of the measuring object WK along the projection direction DR. The aforementioned second slope control program individually controls the first to third moving mechanisms 41-1 to 41-3 (the second slope adjustment mechanism) of the first to third support members 4-1 to 4-3, ensuring that the parallel light from the projection unit 1 is parallel to the surface of the object being measured, WK, along the projection direction DR. The aforementioned contour shape processing program is a program that calculates the contour shape of the peripheral portion of the object being measured, based on the shadow image of the peripheral portion. The program executes the data required for each of these programs using various predetermined data, such as the name of the object being measured, WK, the reference value of the reference object with a known contour shape, and the measurement results.

[0031] Such a memory unit 9 may be, for example, a ROM (Read Only Memory) which is a non-volatile memory element, or an EEPROM (Electrically Erasable Programmable Read Only Memory) which is a rewritable non-volatile memory element. Furthermore, the memory unit 9 contains data stored during the execution of the aforementioned predetermined program, such as RAM (Random Access Memory), which serves as the working memory of the control processing unit 5. The memory unit 9 may also be configured as a hard disk device or a solid-state drive (SSD) with a relatively large memory capacity.

[0032] The control processing unit 5 is a circuit used to control the functions of each part 11, 22, 6-9 of the contour shape measuring device 1000 respectively, and to measure the contour shape of the peripheral part of the object to be measured. The control processing unit 5 is configured, for example, to include a CPU (Central Processing Unit) and its peripheral circuitry. In the control processing unit 5, by executing the aforementioned control processing program, it is functionally configured to include a control unit 51, an image processing unit 52, a first slope control unit 53, a second slope control unit 54, and a contour shape processing unit 55.

[0033] The control unit 51 controls the functions of each part 11, 22, 6-9 of the contour shape measuring device 1000, and thus manages the overall control of the contour shape measuring device 1000.

[0034] The image processing unit 52 performs image processing on the data (raw data) output by the two-dimensional image sensor 22 of the self-image unit 2 using a conventional processing method, thereby generating image data (shadow image data) representing the shadow of the periphery of the measured object WK.

[0035] The first slope control unit 53 controls the slope adjustment mechanism (first slope adjustment mechanism) 35 in such a way that the parallel light from the projection unit 1 is parallel to the surface of the object to be measured WK along the projection direction DR. For example, when the object to be measured, WK, is supported from below by the first to third support members 4-1 to 4-3, and the object to be measured, WK, is positioned between the projection unit 1 and the camera unit 2, the contour shape measuring device 1000 further includes two first and second rangefinders (e.g., laser rangefinders) at two points away from the projection unit 1 and the camera unit 2 along the optical axis AX, which measure the distances from above (or below) to the object to be measured, respectively. The first slope control unit 53 calculates the slope of the optical axis AX with respect to the surface of the object to be measured (the slope of the projection direction DR) based on the difference (distance difference) between the distances measured by the first and second rangefinders, and controls the slope adjustment mechanism 35 in a way that makes the slope of the optical axis AX calculated above zero, or in a way that makes the distance difference above zero.

[0036] The second slope control unit 54 individually controls the first to third moving mechanisms 41-1 to 41-3 (the second slope adjustment mechanism) of the first to third support members 4-1 to 4-3 in such a way that the parallel light from the projection unit 1 is parallel to the surface of the object to be measured WK along the projection direction DR.

[0037] In this embodiment, the posture of the holding member 31 is adjusted by controlling the slope adjustment mechanism 35 so that the parallel light from the projection section 1 is parallel to the surface of the measurement object WK along the projection direction DR (first correction process). The posture of the measurement object WK is adjusted by individually controlling the first to third moving mechanisms 41-1 to 41-3 of the first to third support members 4-1 to 4-3 so that the parallel light from the projection section 1 is parallel to the surface of the measurement object WK along the projection direction DR (second correction process). In this second correction process, as described later, the reference measurement object WK0 is used as the measurement object WK. Thus, in this embodiment, the geometric relationship between the projection direction DR and the surface of the measurement object WK is adjusted in two stages.

[0038] More specifically, if the parallelism is deviated from, the contour shape of the measurement result will deviate from the known contour shape (the contour shape of the measurement result includes errors). Therefore, in order to achieve the aforementioned parallelism, the second slope control unit 54, when measuring the contour shape of a known reference measurement object as the measurement object WK, controls the first to third moving mechanisms 41-1 to 41-3 of the first to third support members 4-1 to 4-3 in a way that minimizes the difference between the known contour shape and the contour shape of the measurement result. More specifically, the outline shape of the aforementioned peripheral portion is divided into multiple parts. For each part, a corresponding relationship is established using one or more predetermined parameters that represent the outline shape of that part. The second slope control unit 54 controls the first to third moving mechanisms 41-1 to 41-3 of the first to third support members 4-1 to 4-3 individually in a way that minimizes the difference between the reference value of one parameter among the multiple parameters of the aforementioned known outline shape and the measured value of the aforementioned parameter of the outline shape of the aforementioned measurement result.

[0039] Regarding the aforementioned individual controls, the second slope control unit 54 executes the following sequentially in a manner that minimizes the aforementioned difference: a first movement control, which controls one of the first and second movement mechanisms 41-1 and 41-2 configured to be relatively close to the first and second support members 4-1 and 4-2 of the aforementioned parallel light (e.g., the first movement mechanism 41-1); a second movement control, which controls the other of the aforementioned first and second movement mechanisms 41-1 and 41-2 (in this example, the second movement mechanism 41-2) in a manner that minimizes the aforementioned difference; and a third movement control, which controls the third movement mechanism 41-3 configured to be relatively far away from the third support member 4-3 of the aforementioned parallel light in a manner that minimizes the aforementioned difference; after executing the aforementioned third movement control, it returns to the aforementioned first movement control and executes the aforementioned first to third movement controls sequentially. Here, the second slope control unit 54, during the sequential execution of the first to third movement controls, determines whether the difference is below a permissible value after each of the first to third movement controls and before executing the next movement control. If the difference is below the permissible value, the next movement control is not executed and the process ends. Conversely, if the difference is not below the permissible value, the next movement control is executed. The permissible value can, for example, be appropriately preset based on a plurality of samples.

[0040] Using Figures 6 and 7, the second slope control unit 54 will be explained in more detail. Figure 6 is a diagram illustrating multiple parameters of the contour shape as an example. Figure 7 is a diagram illustrating the calibration of the support member of the aforementioned contour shape measuring device. The horizontal axis of Figure 7 is the first support position [μm], and its vertical axis parameter is A1 [μm].

[0041] In Figure 6, the outline shape OL of the measured object WK is illustrated with a relatively thick solid line. The outline shape OL of the aforementioned peripheral portion, in the example shown in Figure 6, is divided into a beveled portion (surface bevel) SB of the surface (one of the main surfaces), a beveled portion (inner bevel) RB of the inner surface (the other main surface opposite to one of the main surfaces), and a front end portion FE. For the surface bevel SB and the inner bevel RB, a correspondence is established between three parameters: the inclination angles θ1 and θ2, the bevel lengths A1 and A2, and the bevel heights B1 and B2, respectively. For the front end portion FE, a correspondence is established between one parameter: the position of the front end c (front end position) C. The inclination angle θ1 of the surface bevel SB is the angle formed between the surface of the surface bevel SB and the surface of the measured object WK, and is represented by this angle. The inclined length A1 of the surface inclined section SB, the starting point a1 of the surface inclined section SB, and the distance between the intersection line e1 of the surface of the surface inclined section SB and the tangent of the front end c are expressed as this length. The starting point a1 of the surface inclined section SB is the position where the surface of the measured object WK begins to tilt. The surface inclined section SB is the distance from the starting point a1 of the surface inclined section SB to the position where the surface of the surface inclined section SB deviates from the tilt angle θ1 of the surface inclined section SB. The inclined height B1 of the surface inclined section SB is the distance between the surface of the measured object WK and the intersection line e1 of the surface of the surface inclined section SB and the tangent of the front end c, expressed as this length. Similarly, the tilt angle θ2 of the inner inclined section RB is the angle formed between the surface of the inner inclined section RB and the inner surface of the measured object WK, expressed as this angle. The starting point a2 of the inner inclined section RB is the position where the inner surface of the measured object WK begins to tilt. The length A2 of the inclined surface RB is the distance between the starting point a2 of the inner inclined surface RB and the intersection line e2 of the surface of the inner inclined surface RB and the tangent surface of the front end c, and is expressed as this length. The height B2 of the inclined surface RB is the distance between the surface of the measured object WK and the intersection line e2 of the surface of the inner inclined surface RB and the tangent surface of the front end c, and is expressed as this length. The inner inclined surface RB extends from the starting point a2 of the inner inclined surface RB to the position where the surface of the inner inclined surface RB deviates from the inclination angle θ2 of the inner inclined surface RB. The front end FE is located between the surface inclined surface SB and the inner inclined surface RB.

[0042] All or multiple of the seven parameters A1, A2, B1, B2, θ1, θ2, and C may be used. However, these seven parameters A1, A2, B1, B2, θ1, θ2, and C are interdependent, and their values ​​are linked. Therefore, in this embodiment, one parameter among the seven parameters A1, A2, B1, B2, θ1, θ2, and C is used, for example, parameter A1 (the slope length A1 of the inclined surface SB). Of course, any one of the other parameters A2, B1, B2, θ1, θ2, and C may also be used. Furthermore, the parameters are not limited to A1, A2, B1, B2, θ1, θ2, and C. If the parameter is a parameter characterizing the contour shape of the periphery of the measured object WK, then other parameters may also be used.

[0043] When adjusting the posture of the measurement object WK in the second slope control unit 54, a reference measurement object WK0 (not shown) is first selected, and parameter A1 is used as the reference value of parameter A1; y0 is actually measured. For example, among a plurality of measurement objects WK, an appropriate one is selected as the reference measurement object WK0. When the measurement object WK is an industrial product, there is almost no difference between products, so the reference measurement object WK0f can be selected from a plurality of measurement objects WK. Furthermore, for example, by means of a vernier caliper or a 3D shape measuring machine, the user actually measures the parameter A1 of the reference measurement object WK0, and the aforementioned actually measured parameter A1; y0 is input to the contour shape measuring device 1000 through the input unit 6 and used as the reference value of parameter A1; y0 is stored in the memory unit 9.

[0044] Alternatively, for example, the parameter A1;y0 of the reference measurement object WK0 can be obtained using another contour shape measuring device 1000 that has been adjusted, and stored in the memory unit 9 as the reference value of parameter A1;y0. Furthermore, the aforementioned mounting device (not shown in the figure) adjusts its operation by placing the measurement object WK and the reference measurement object WK0 on the first to third support members 4-1 to 4-3 so that the center positions of the measurement object WK and the reference measurement object WK0 are aligned with the center positions of the first to third support members 4-1 to 4-3 (the center position of the circumcircle of the aforementioned isosceles triangle).

[0045] First, using the aforementioned mounting device (not shown in the diagram), the reference measurement object WK0 is mounted on the first to third support members 4-1 to 4-3. Furthermore, as mentioned above, since there is almost no difference between the products, the reference measurement object WK can be used as the reference measurement object WK0.

[0046] Next, the second slope control unit 54 controls one of the first and second moving mechanisms 41-1 and 41-2 in a manner that minimizes the aforementioned difference; in this case, it controls the first movement of the first moving mechanism 41-1. More specifically, the second slope control unit 54 moves the first moving mechanism vertically within a preset scanning range and at a preset scanning interval. Each time the mechanism moves at the aforementioned scanning interval, the contour shape processing unit 55 obtains the parameter A1 at the first support position and establishes a correspondence between the obtained measured parameter A1 and the aforementioned first support position (or number of movements), storing it in the memory unit 9. Furthermore, before the scan begins, the first moving mechanism 41-1 is set to a preset position (initial position) where the first support position is appropriately set. Next, when the scan is complete, the second slope control unit 54, using the first support position and parameter A1 as the x-axis and y-axis coordinates respectively, plots each measurement result on the coordinates represented by each first support position and each parameter A1, and finds the curve (or straight line) that best fits each measurement result; y=f(x). In this way, the relationship between the first support position; x and parameter A1; y; f is obtained. For example, in the example shown in Figure 7, the scanning range is set to -10 [μm] to +40 [μm] for the aforementioned preset (initial position); 0, and the scanning interval is set to 5 [μm]. At each of the first support positions at -10 [μm], -5 [μm], 0 [μm], +5 [μm], +10 [μm], +15 [μm], +20 [μm], +25 [μm], +30 [μm], +35 [μm], and +40 [μm], the actual measured parameters A1 are y. Next, the second slope control unit 54, as shown in Figure 7, substitutes the parameter A1; y of the curve (or straight line); y=f(x) obtained above into the reference value of parameter A1; y0 stored in the memory unit 9, and obtains the first support position in this case; x0 (y0=f(x0)). Next, the second slope control unit 54 controls the first moving mechanism 41-1 in such a way that it becomes the first support position x0 obtained above. In this way, the first movement control of the first moving mechanism 41-1 is performed in such a way that the aforementioned difference is minimized.

[0047] Next, the second slope control unit 54 obtains the parameter A1; y0r at the first support position; x0 using the contour shape processing unit 55 and stores it in the memory unit 9. Then, the second slope control unit 54 determines whether the difference between the reference value; y0 of parameter A1 and the measured value; y0r of parameter A1 obtained from the previous measurement result is below an allowable value. If the difference is below an allowable value, the second slope control unit 54 does not execute the next second movement control and ends. On the other hand, if the difference is not below an allowable value, the second slope control unit 54 executes the next second movement control.

[0048] In order to minimize the aforementioned difference, in this example, in the second movement control of the second movement mechanism 41-2, the second slope control unit 54 replaces the first movement mechanism 41-1 and operates in the same way as the first movement control for the second movement mechanism 41-2. That is, the second slope control unit 54 obtains a curve (or straight line) that best fits the measurement results of each parameter A1 of each second support position obtained by scanning the second support position with the aforementioned scanning range and the aforementioned scanning interval, and controls the second movement mechanism 41-2 in such a way that the obtained curve (or straight line) is substituted into the reference value y0 of parameter A1 stored in the memory unit 9 to obtain the second support position.

[0049] Next, the second slope control unit 54 obtains the parameter A1 at the second support position through the contour shape processing unit 55, and determines whether the difference between the reference value y0 of parameter A1 and the measured value y0r of parameter A1 obtained from the previous measurement result is below an allowable value. If the difference is below an allowable value, the second slope control unit 54 does not execute the next third movement control and ends. On the other hand, if the difference is not below an allowable value, the second slope control unit 54 executes the next third movement control.

[0050] In order to minimize the aforementioned difference, in this example, in the third movement control of the third movement mechanism 41-3, the second slope control unit 54 replaces the first movement mechanism 41-1 and operates in the same way as the first movement control for the third movement mechanism 41-3. That is, the second slope control unit 54 obtains a curve (or straight line) that best fits the measurement results of each parameter A1 of each third support position obtained by scanning the third support position with the aforementioned scanning range and the aforementioned scanning interval, and controls the third movement mechanism 41-3 in such a way that the obtained curve (or straight line) is substituted into the reference value y0 of parameter A1 stored in the memory unit 9 to obtain the third support position.

[0051] Next, the second slope control unit 54 obtains the parameter A1 at the third support position through the contour shape processing unit 55, and determines whether the difference between the reference value y0 of parameter A1 and the measured value y0r of parameter A1 obtained from the previous measurement result is below an allowable value. If the difference is below an allowable value, the second slope control unit 54 does not execute the next first movement control and ends. On the other hand, if the difference is not below an allowable value, the second slope control unit 54 executes the next first movement control.

[0052] The first to third movement processes are executed sequentially in a loop after each movement control until the difference between the reference value of parameter A1, y0 and the measured value of parameter A1, becomes below the allowable value.

[0053] Furthermore, there may be situations where, even if the process is executed sequentially as described above, the difference still does not fall below the allowable value. Therefore, for example, the contour shape measuring device 1000 may be configured such that the number of times the first to third movement controls are executed sequentially (number of cycles) is appropriately set in advance to 3 or 5 times. If, even after the aforementioned number of cycles is completed, the difference still does not fall below the allowable value, the first to third movement controls are terminated, and an error message (e.g., "Unable to be corrected. Please contact the manufacturer for repair.") is output to the output unit 7.

[0054] When adjusting using multiple parameters, the process is as follows: For each parameter, the support position x0 is obtained using the aforementioned method. The average value of the multiple obtained support positions x0 is calculated, and the moving mechanism is controlled using this average value. The adjustment ends when the difference between the reference value and the measured value of all parameters is below the allowable value set for each parameter.

[0055] Returning to Figures 1 to 5, the contour shape processing unit 55 obtains the contour shape of the periphery of the measured object WK based on the shadow image of the periphery. Next, the contour shape processing unit 55 obtains each parameter A1, A2, B1, θ1, θ2, and C from each of the generated straight lines or curves, and stores them in the memory unit 9.

[0056] The control processing unit 5, input unit 6, output unit 7, IF unit 8, and memory unit 9 of such a contour shape measuring device 1000 can be, for example, a computer such as a desktop or notebook computer.

[0057] Next, the operation of this embodiment will be explained. Figure 8 is a flowchart showing the operation of the aforementioned contour shape measuring device for correcting the previously described contour shape. Figure 9 is a flowchart showing the operation of the aforementioned contour shape measuring device for correcting the support member shown in Figure 8.

[0058] When the power is turned on, the contour shape measuring device 1000, as configured in this way, performs the necessary initialization of each part and begins to operate. The control processing unit 5 is functionally configured with a control unit 51, an image processing unit 52, a first slope control unit 53, a second slope control unit 54 and a contour shape processing unit 55 by executing the control processing program.

[0059] When the user (operator) instructs to start the calibration through the input unit 6, in Figure 8, firstly, the contour shape measuring device 1000 controls the slope adjustment mechanism 35 through the first slope control unit 53 of the control processing unit 5, thereby adjusting the posture of the holding member 31 so that the parallel light of the projection unit 1 is parallel to the surface of the measuring object WK along the projection direction DR (S1, first calibration processing).

[0060] Next, the contour shape measuring device 1000 controls the first to third moving mechanisms 41-1 to 41-3 of the first to third support members 4-1 to 4-3 by the second slope control unit 54 of the control processing unit 5, thereby adjusting the posture of the measuring object WK (reference measuring object WK0) in such a way that the parallel light of the projection unit 1 is parallel to the surface of the measuring object WK along the projection direction DR (S2, second correction processing), and ends this process.

[0061] In the second correction process S2, as shown in FIG9, the contour shape measuring device 1000 first places the reference measuring object WK0 on the first to third support members 4-1 to 4-3 by means of the control processing unit 5 and the aforementioned placement device (not shown) (S11).

[0062] Next, the contour shape measuring device 1000 performs first movement control (S12) to correct the first support member 4-1 by means of the second slope control unit 54.

[0063] Next, the contour shape measuring device 1000, at the first support position after executing the first movement control in process S12, determines whether the difference between the reference value of parameter A1 and the measured value of parameter A1 is below an allowable value (S13). If the result of this determination is that the difference is below an allowable value (Yes), the second slope control unit 54 does not execute the next second movement control and executes process S18. On the other hand, if the result of the determination is that the difference is not below an allowable value (No), the second slope control unit 54 executes process S14 to execute the next second movement control.

[0064] In processing S14, the contour shape measuring device 1000 performs second movement control by correcting the second support member 4-2 through the second slope control unit 54.

[0065] Next, the contour shape measuring device 1000, at the second support position after executing the second movement control in process S14, determines whether the difference between the reference value of parameter A1 and the measured value of parameter A1 is below an allowable value (S15). If the result of this determination is that the difference is below an allowable value (Yes), the second slope control unit 54 does not execute the next third movement control and executes process S18. On the other hand, if the result of the determination is that the difference is not below an allowable value (No), the second slope control unit 54 executes the next third movement control and executes process S16.

[0066] In processing S16, the contour shape measuring device 1000 performs third movement control by correcting the third support member 4-3 through the second slope control unit 54.

[0067] Next, the contour shape measuring device 1000, at the third support position after executing the third movement control in process S16, determines whether the difference between the reference value of parameter A1 and the measured value of parameter A1 is below the allowable value (S17). If the result of this determination is that the difference is below the allowable value (Yes), the second slope control unit 54 does not execute the next first movement control and executes process S18. On the other hand, if the result of the determination is that the difference is not below the allowable value (No), the second slope control unit 54 executes the next first movement control, causing the process to return to process S12.

[0068] In the aforementioned process S18, the contour shape measuring device 1000 terminates the process by announcing the end of the correction through the second slope control unit 54. The aforementioned announcement is, for example, outputting a message indicating the end of correction, such as "Correction completed.", to the output unit 7.

[0069] Furthermore, the aforementioned calibration does not need to be performed for every measurement, but can be performed at appropriate intervals (regularly or irregularly) as needed. For example, in the case where the measurement object WK is supported by the support member 4, if the support claw member 42 is formed of a material softer than the measurement object WK in order not to damage the measurement object WK, the support surface TF of the support claw member 42 will wear down after repeated measurements, causing the support position to deviate. Therefore, when the predetermined number of measurements is reached, the aforementioned calibration is performed by the user's instruction to start calibration, or by the determination of the number of measurements performed by the contour shape measuring device 1000.

[0070] As explained above, the contour shape measuring device 1000 and the contour shape measuring method of the embodiment support the measuring object WK from below at least 3 points with at least the first to third support members 4-1 to 4-3, and individually control the first to third moving mechanisms 41-1 to 41-3 of the first to third support members 4-1 to 4-3 that move the first to third support positions of the measuring object WK in the vertical direction. Therefore, without reinstalling the projection unit 1 and the camera unit 2, the posture of the measuring object WK can be adjusted with 2 degrees of freedom, thus the posture of the measuring object WK can be adjusted more appropriately.

[0071] The aforementioned contour shape measuring device 1000 and contour shape measuring method are capable of using a known contour shape to measure the first to third support positions of the first to third support members 4-1 to 4-3, and using a reference object WK0 to measure the first to third support positions, so that the parallel light is parallel to the surface of the object WK along the projection direction.

[0072] The aforementioned contour shape measuring device 1000 and contour shape measuring method are calibrated using one of a plurality of parameters, thus simplifying the calibration process.

[0073] The aforementioned contour shape measuring device 1000 and contour shape measuring method sequentially execute the first to third movement processes in a cyclic manner until the aforementioned difference becomes below the allowable value, thus enabling more accurate correction.

[0074] When the disc-shaped object WK is relatively thin, if the distance between the support positions is long, the object WK may be prone to deflection. If the periphery to which parallel light is projected is deflected, the accuracy of the measurement of the periphery's contour shape will deteriorate. Therefore, it is preferable to have a shorter distance between the first and second support positions that support the periphery to which parallel light is projected. If the first to third support members 4-1 to 4-3 are arranged such that the first to third support positions are located at the vertices of an equilateral triangle, then the distances between the support positions of the first to third support positions will be equal. However, the aforementioned contour shape measuring device 1000 and contour shape measuring method arrange the first to third support members 4-1 to 4-3 such that the vertices of an isosceles triangle with the line segment connecting the first support position and the second support position as the base are arranged such that the distance between the support positions of the first and second support positions (the 12th distance) is shorter than the distance between the support positions of the first and third support positions (the 13th distance) and the distance between the support positions of the second and third support positions (the 23rd distance). Therefore, the aforementioned risk of deflection can be reduced, and the degradation of measurement accuracy can be reduced.

[0075] The aforementioned contour shape measuring device 1000 and contour shape measuring method are configured with the first to third support members 4-1 to 4-3 facing the inside of the triangle with the inclined first to third support surfaces facing the inside of the triangle. Therefore, when the first to third support members 4-1 to 4-3 are individually controlled in the vertical direction, horizontal movement (movement in the XY plane) will be hindered. Thus, the first to third support members 4-1 to 4-3 can more reliably support the measuring object WK, thereby reducing the risk of the measuring object WK detaching from the support of the first to third support members 4-1 to 4-3.

[0076] Furthermore, in the aforementioned embodiment, the second correction process is executed by the first to third movement controls; however, it can also be executed by the first and second movement controls (a variation of the second correction process). More specifically, the second slope control unit 54 interactively executes the first movement control of one of the first and second movement mechanisms 41-1 and 41-2 of the first and second support members 4-1 and 4-2 (e.g., the first movement mechanism 41-1) and the second movement control of the other of the aforementioned first and second movement mechanisms 41-1 and 41-2 (in this example, the second movement mechanism 41-2) in such a way that the difference between the reference value of one of the plurality of parameters of the known contour shape and the measured value of the aforementioned parameter of the measured contour shape is below an allowable value. By adjusting the first and second support positions of the first and second support members 4-1 and 4-2, which are positioned relatively close to the parallel light, correction can be performed in most cases. The aforementioned profile shape measuring device 1000 of the deformed form performs the first and second movement processes alternately in such a way that the aforementioned difference is below the allowable value, thus enabling correction in a shorter time.

[0077] Figure 10 is a flowchart showing the operation of the aforementioned contour shape measuring device for correcting the support member of the deformed form. In the second correction process of the contour shape measuring device 1000 for the deformed form, instead of the aforementioned operation shown in Figure 9, the following operation shown in Figure 10 is performed.

[0078] In Figure 10, firstly, the contour shape measuring device 1000 is the same as the aforementioned process S11, placing the reference measuring object WK0 on the first to third support members 4-1 to 4-3 (S21), and the same as the aforementioned process S12, executing the first movement control (S22) to correct the first support member 4-1.

[0079] Next, the contour shape measuring device 1000, at the first support position after executing the first movement control in process S22, determines whether the difference between the reference value of parameter A1 and the measured value of parameter A1 is below an allowable value (S23). If the result of this determination is that the difference is below an allowable value (Yes), the second slope control unit 54 does not execute the next second movement control and executes process S26. On the other hand, if the result of the determination is that the difference is not below an allowable value (No), the second slope control unit 54 executes process S24 to execute the next second movement control.

[0080] In process S24, the contour shape measuring device 1000 is the same as in process S14, and performs second movement control to correct the second support member 4-2.

[0081] Next, the contour shape measuring device 1000, at the second support position after executing the second movement control in process S24, determines whether the difference between the reference value of parameter A1 and the measured value of parameter A1 is below an allowable value (S25). If the result of this determination is that the difference is below an allowable value (Yes), the second slope control unit 54 does not execute the next first movement control and executes process S26. On the other hand, if the result of the determination is that the difference is not below an allowable value (No), the second slope control unit 54 executes the next first movement control, causing the process to return to process S22.

[0082] In the aforementioned process S26, the contour shape measuring device 1000, in the same manner as in the aforementioned process S18, reports the completion of the calibration and ends the process.

[0083] This specification discloses various forms of technology as described above, but summarizes the main technologies therein as follows.

[0084] A contour shape measuring device comprises: a device that projects parallel light from the tangential direction of the outer periphery of a circular plate-shaped measuring object, captures the shadow of the periphery generated by the parallel light, and measures the contour shape of the periphery based on the captured image of the shadow of the periphery; the contour shape measuring device includes: at least three first to third support members for supporting the measuring object from below at at least three points; and a control unit that controls the first to third support members in such a way that the parallel light is parallel to the surface of the measuring object along the projection direction, based on the image of the shadow of the periphery; the first to third support members are equipped with first to third moving mechanisms for moving the first to third support positions of the measuring object in a vertical direction, and the control unit individually controls the first to third moving mechanisms.

[0085] Such a contour shape measuring device supports the measuring object from below at least 3 points with at least the first to the third support members, and individually controls the first to the third moving mechanism of the first to the third support members of the measuring object to move the first to the third support positions of the measuring object in the vertical direction. Therefore, without reinstalling the projection part and the camera part, the posture of the measuring object can be adjusted with 2 degrees of freedom, so the posture of the measuring object can be adjusted more appropriately.

[0086] In other forms, such as the aforementioned contour shape measuring device, the aforementioned control unit, in order to achieve the aforementioned parallelism, when measuring the aforementioned contour shape using a known reference measuring object as the measuring object, individually controls the aforementioned first to third moving mechanisms in a manner that minimizes the difference between the known contour shape and the measured contour shape.

[0087] Such a contour shape measuring device is able to measure the first to third support positions of the first to third support members using a reference object with a known contour shape, so that the aforementioned parallel light and the surface of the aforementioned measuring object are parallel along the projection direction.

[0088] In other forms, such as the aforementioned contour shape measuring device, the contour shape of the aforementioned peripheral portion is divided into a plurality of parts, and for the aforementioned parts, one or a plurality of parameters are established in a corresponding relationship. The aforementioned control unit individually controls the aforementioned first to third moving mechanisms based on the difference between the reference value of each of the aforementioned one or a plurality of parameters of the aforementioned known contour shape and the measured value of each of the aforementioned one or a plurality of parameters of the aforementioned measured contour shape.

[0089] Such a contour shape measuring device is capable of individually controlling the first to third moving mechanisms based on the difference between each reference value and each measured value of one or more of the aforementioned parameters.

[0090] In other forms, such as the aforementioned contour shape measuring device, the contour shape of the aforementioned peripheral portion is divided into a plurality of parts, and for the aforementioned parts, one or a plurality of parameters are established in a corresponding relationship. The aforementioned control unit individually controls the aforementioned first to third moving mechanisms in a manner that minimizes the difference between the reference value of one parameter among the plurality of parameters of the aforementioned known contour shape and the measured value of the aforementioned parameter of the aforementioned measured contour shape.

[0091] Such a contour shape measuring device uses one of a plurality of parameters for calibration, thus simplifying the calibration process.

[0092] In other configurations, such as the aforementioned contour shape measuring device, the first to third support members are arranged such that the first to third support positions are located at the vertices of a triangle; the first and second support members are positioned relatively close to the aforementioned parallel light; and the third support member is positioned relatively far from the aforementioned parallel light. The control unit sequentially executes: a first movement control, which controls one of the first and second movement mechanisms based on the aforementioned difference; a second movement control, which controls the other of the first and second movement mechanisms based on the aforementioned difference; and a third movement control, which controls the other based on the aforementioned difference. The aforementioned difference controls the aforementioned third movement mechanism; after executing the aforementioned third movement control, it returns to the aforementioned first movement control and sequentially executes the aforementioned first to third movement controls. During the sequential execution of the aforementioned first to third movement controls, after executing each of the aforementioned first to third movement controls and before executing the next movement control, it is determined whether the value of the aforementioned difference is below the allowable value. If the value of the aforementioned difference is below the allowable value, the next movement control is not executed and the process ends. On the other hand, if the value of the aforementioned difference is not below the allowable value, the next movement control is executed.

[0093] Such a contour shape measuring device performs the first to third movement processes in a cyclical manner until the difference value becomes below the allowable value, thus enabling more accurate correction.

[0094] In other forms, such as the aforementioned contour shape measuring device, the first to third support members are arranged such that the first to third support positions are located at the vertices of the triangle, the first and second support members are arranged relatively close to the aforementioned parallel light, and the third support member is arranged relatively far away from the aforementioned parallel light. The aforementioned control unit interactively executes a first movement control of one of the aforementioned first and second movement mechanisms and a second movement control of the other of the aforementioned first and second movement mechanisms, in such a way that the difference between the reference value of one of the known contour shape parameters and the measured value of the measured contour shape of the aforementioned first parameter is below an allowable value.

[0095] By adjusting the positions of the first and second support members, which are positioned relatively close to the parallel light, correction can be performed in most cases. The aforementioned contour shape measuring device performs the first and second movement processes alternately in such a way that the difference value is below the allowable value, thus enabling correction in a shorter time.

[0096] In other forms, such as the aforementioned contour shape measuring device, the first to third support members are configured such that the length of the first line segment connecting the first support position and the second support position is shorter than the length of the second line segment connecting the first support position and the third support position, and the first and second support members are positioned relatively close to the aforementioned parallel light, while the third support member is positioned relatively far away from the aforementioned parallel light.

[0097] When the disc-shaped object being measured is relatively thin, a long distance between the support positions may cause the object to warp. If the periphery to which parallel light is projected warps, the accuracy of measuring the contour shape of the periphery will deteriorate. Therefore, it is preferable to have a shorter distance between the first and second support positions that support the periphery to which parallel light is projected. If the first to third support members are arranged such that the first to third support positions are located at the vertices of an equilateral triangle, then the distances between the support positions of the first to third support positions will be equal. However, the aforementioned contour shape measuring device arranges the first to third support members such that the line segment connecting the first and second support positions is used as the base of an isosceles triangle. Therefore, the distance between the support positions of the first and second support positions (the 12th distance) is shorter than the distance between the support positions of the first and third support positions (the 13th distance) and the distance between the support positions of the second and third support positions (the 23rd distance). Thus, the aforementioned risk of deflection can be reduced, and the degradation of measurement accuracy can be mitigated.

[0098] In other forms, such as the aforementioned contour shape measuring device, the first to third support members further include: first to third support claw members, which have inclined first to third support surfaces such that they make point contact with the periphery of the measuring object; the first to third support members are arranged such that the first to third support positions are located at the vertices of a triangle and the first to third support surfaces face the inner side of the triangle; the first to third moving mechanisms are connected to the first to third support claw members to move the first to third support claw members in the vertical direction.

[0099] Such a contour shape measuring device arranges the first to third support members in such a way that the inclined first to third support surfaces face the inner side of the aforementioned triangle. Therefore, when the first to third support members are individually controlled in the vertical direction, the first to third support members can more reliably support the measuring object, thereby reducing the risk of the measuring object detaching from the support of the first to third support members.

[0100] Another method for measuring the contour shape of a circular plate-shaped object is as follows: A method in which parallel light is projected from the tangential direction of the outer periphery onto the periphery of the object being measured, and the shadow of the periphery generated by the parallel light is captured by an image. The contour shape of the periphery is then measured based on the image of the shadow of the periphery captured by the image. This contour shape measurement method includes: a support step in which the object being measured is supported from below at at least three points by at least three first to third support members; and a control step in which the first to third support members are controlled by a control unit based on the image of the shadow of the periphery, such that the parallel light is parallel to the surface of the object being measured along the projection direction. The first to third support members are equipped with first to third moving mechanisms that move the first to third support positions of the object being measured vertically. The control step individually controls the first to third moving mechanisms.

[0101] This contour shape measurement method involves supporting the object to be measured from below at least three points with at least the first to the third support members, and individually controlling the first to the third support positions of the object to be measured to move the first to the third support members of the first to the third support members in the vertical direction. Therefore, without reinstalling the projection unit and the camera unit, the posture of the object to be measured can be adjusted with two degrees of freedom, thus enabling more appropriate adjustment of the posture of the object to be measured.

[0102] This application is based on Japanese Patent Application No. 2024-174799 filed on October 4, 2024, the contents of which are included in this application.

[0103] To illustrate the present invention, it has been appropriately and fully described through embodiments with reference to the foregoing drawings. However, it should be understood that those skilled in the art can easily modify and / or improve the foregoing embodiments. Therefore, any modifications or improvements made by those skilled in the art, without departing from the scope of the claims described in the patent application, are also included in the scope of the claims.

[0104] 1: Light projection department 11: Light source 12: Illumination Optical System 121: Collimating Lens 122: First masking plate 123: Second masking plate 2: Camera Department 21: Light-receiving optical system 211: Lens No. 1 212: Aperture 213: Second Lens 22: Two-dimensional image sensor 3: Optical system holding section 31: Retaining Components 311: Maintain the board section 312: Vertical board department 32: Support shaft 33: Shaft support components 34:Pedestal component 35: Slope Adjustment Mechanism 351: Rod Member 352: Servo Motor 353: Worm Gear 354: Worm Gear 4-1: First Support Component 4-2: Second Support Component 4-3: Third Support Component 41-1: First moving mechanism 41-2: Second moving mechanism 41-3: Third moving mechanism 42-1: First support claw component 42-2: Second support claw component 42-3: Third support claw component 5: Control Processing Unit 51: Control Department 52: Image Processing Department 53: First slope control section 54: Second slope control section 55: Contour Shape Processing Department 6: Input Section 7: Output Section 8: Interface Department (IF Department) 9: Memory Department 1000: Profile Shape Measuring Device WK: Subject of measurement OL: Outline shape RB: Inside oblique face SB: Surface bevel part A1, A2: Inclined plane lengths B1, B2: Inclined height a1: The starting point of SB on the beveled surface. a2: The starting point of RB on the oblique surface inside. θ1, θ2: Inclination angle e1: Crossover e2: Crossover AX: Optical axis c(C): Frontend (Frontend Position) DR: light direction FE: Front end TF-1: First support surface TF-2: Second Support Surface TF-3: Third Support Surface

Claims

1. A contour shape measuring device, wherein parallel light is projected from the tangential direction of the outer periphery of a circular plate-shaped measuring object, and the shadow of the periphery generated by the parallel light is captured by an image, and the contour shape of the periphery is measured based on the image of the shadow of the periphery captured by the image; the contour shape measuring device comprises: at least three first to third support members for supporting the measuring object from below at at least three points; and a control unit that controls the first to third support members in such a way that the parallel light is parallel to the surface of the measuring object along the projection direction, based on the image of the shadow of the periphery; the first to third support members are equipped with first to third moving mechanisms for moving the first to third support positions of the measuring object in a vertical direction, and the control unit individually controls the first to third moving mechanisms.

2. The contour shape measuring device as described in claim 1, wherein, In order to achieve the aforementioned parallelism, when measuring the aforementioned contour shape using a reference object with a known contour shape as the measurement object, the aforementioned control unit individually controls the aforementioned first to third moving mechanisms in a manner that minimizes the difference between the known contour shape and the contour shape of the measurement result.

3. The contour shape measuring device as described in claim 2, wherein, The outline shape of the aforementioned peripheral portion is divided into multiple parts. For each of the aforementioned parts, one or more parameters are established to correspond to each other. The aforementioned control unit controls the aforementioned first to third moving mechanisms individually based on the difference between the reference value of each of the aforementioned one or more parameters of the known outline shape and the measured value of each of the aforementioned one or more parameters of the outline shape of the aforementioned measurement result.

4. The contour shape measuring device as described in claim 2, wherein, The aforementioned peripheral contour shape is divided into multiple parts. For each part, one or more parameters are established to correspond to it. The aforementioned control unit individually controls the aforementioned first to third moving mechanisms in a way that minimizes the difference between the reference value of one parameter among the multiple parameters of the aforementioned known contour shape and the measured value of the aforementioned parameter of the aforementioned measured contour shape.

5. The contour shape measuring device as described in claim 3, wherein, The aforementioned first to third support members are arranged such that the first to third support positions are located at the vertices of a triangle. The aforementioned first and second support members are arranged relatively close to the aforementioned parallel light, and the aforementioned third support member is arranged relatively far away from the aforementioned parallel light. The aforementioned control unit sequentially executes: a first movement control, which controls one of the aforementioned first and second movement mechanisms based on the aforementioned difference; a second movement control, which controls the other of the aforementioned first and second movement mechanisms based on the aforementioned difference; and a third movement control, which controls the aforementioned third movement mechanism based on the aforementioned difference; after executing the aforementioned third movement control, it returns to the aforementioned first movement control and sequentially executes the aforementioned first to third movement controls. During the sequential execution of the first to third movement controls, after each of the first to third movement controls is executed and before the next movement control is executed, it is determined whether the value of the difference is below the allowable value. If the difference is below the allowable value, the next movement control is not executed and the process ends. On the other hand, if the difference is not below the allowable value, the next movement control is executed.

6. The contour shape measuring device as described in claim 3, wherein, The aforementioned first to third support members are configured such that the aforementioned first to third support positions are located at the vertices of the triangle. The aforementioned first and second support members are configured relatively close to the aforementioned parallel light. The aforementioned third support member is configured relatively far away from the aforementioned parallel light. The aforementioned control unit interactively executes the following actions until the difference value is below the allowable value: a first movement control controls one of the aforementioned first and second movement mechanisms to minimize the aforementioned difference; and a second movement control controls the other of the aforementioned first and second movement mechanisms to minimize the aforementioned difference.

7. The contour shape measuring device as described in any one of claims 1 to 6, wherein, The aforementioned first to third support members are configured such that the length of the first line segment connecting the aforementioned first support position and the aforementioned second support position is shorter than the length of the second line segment connecting the aforementioned first support position and the aforementioned third support position, and the aforementioned first line segment is the vertex of an isosceles triangle with the aforementioned first line segment as the base. The aforementioned first and second support members are configured relatively close to the aforementioned parallel light, and the aforementioned third support member is configured relatively far away from the aforementioned parallel light.

8. The contour shape measuring device as described in any one of claims 1 to 6, wherein, The aforementioned first to third support members are further provided with: first to third support claw members, which have inclined first to third support surfaces such that they make point contact with the periphery of the aforementioned measuring object; the aforementioned first to third support members are arranged such that the aforementioned first to third support positions are located at the vertices of a triangle and the aforementioned first to third support surfaces face the inner side of the aforementioned triangle; the aforementioned first to third moving mechanisms are connected to the aforementioned first to third support claw members to move the aforementioned first to third support claw members in the vertical direction.

9. A method for measuring contour shape, wherein parallel light is projected from the tangential direction of the outer periphery of a circular plate-shaped measuring object, and the shadow of the periphery generated by the parallel light is captured by an image, and the contour shape of the periphery is measured based on the image of the shadow of the periphery captured by the image; the method for measuring contour shape includes: a support step, wherein the measuring object is supported from below at at least three points by at least three first to third support members; and a control step, wherein the first to third support members are controlled by a control unit based on the image of the shadow of the periphery, such that the parallel light is parallel to the surface of the measuring object along the projection direction; the first to third support members are equipped with first to third moving mechanisms for moving the first to third support positions of the measuring object in a vertical direction; and the control step individually controls the first to third moving mechanisms.

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