JP6986219B2 - Shape measuring device, shape measuring program and shape measuring method - Google Patents

Description

The present technology relates to a shape measuring device for measuring the shape of an object to be measured.

As a shape measuring device that measures the shape of the object to be measured, an angle detector that optically detects the tilt angle of the measurement surface is used, and a device that derives the shape of the measurement surface based on the position and tilt angle of the measurement point. It has been proposed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2003-161615

An embodiment of the present technology is a shape measuring device. In the shape measuring device of this embodiment, the work holder holding the object to be measured and the probe light irradiate the measurement surface of the object to be measured, and the angle of the measurement surface is based on the probe light reflected by the measurement surface. By moving the work holder and the angle detector relative to each other, the probe light irradiating the measurement surface is moved in the axial directions of the first axis, the second axis, and the third axis. An irradiation position moving mechanism to be moved, a position state detector that detects the position state of the work holder and the angle detector in each axis direction of the first axis, the second axis, and the third axis, and the measurement surface. The positions of the work holder and the angle detector are controlled so that the probe light is incident on the target measurement point in a predetermined incident state, and the angle detector detects the detection. The first axis includes a control unit that derives the shape of the measurement surface based on the angle of the measurement surface, and the control unit detects a preset reference shape of the measurement surface by the position state detector. , The actual measurement surface to which the probe light is irradiated based on the position state of the second axis and the position state of the third axis is reset based on the position state of the other two axes. The measurement point is specified, and the angle of the measurement surface detected by the angle detector is corrected based on the inclination angle of the specified actual measurement point in the reference shape to obtain the inclination angle of the actual measurement point. , It is configured to derive the shape of the measurement surface.

Another aspect illustrating this technique is a shape measuring method. In this shape measurement method, the probe light emitted by the angle detector is incidentally incident on the target measurement point on the measurement surface of the object to be measured held by the work holder in a predetermined incident state. As described above, the work holder and the angle detector are moved relative to each other to control the positions of the probe light irradiating the measurement surface in the axial directions of the first axis, the second axis, and the third axis. The measurement surface is irradiated with the probe light to detect the angle of the measurement surface, and the work holder and the angle detector have the first axis, the second axis, and the third axis by the position state detector. The position state of each axis direction is detected, and the position state of the first axis, the second axis, and the third axis detected by the position state detector in the preset reference shape of the measurement surface. The actual measurement point of the measurement surface irradiated with the probe light is specified based on the position and state of the other two axes, and the actual measurement point is specified. Includes correcting the angle of the measurement surface detected by the angle detector based on the inclination angle in the reference shape of the above to obtain the inclination angle of the actual measurement point, and deriving the shape of the measurement surface. Consists of.

Yet another embodiment illustrating this technique is a shape measuring program for causing a computer to perform the shape measuring method.

It is a schematic block diagram of the shape measuring apparatus which illustrates the aspect of this technique. It is a schematic block diagram of the control system of the said shape measuring apparatus. It is a schematic diagram of the optical unit seen in the direction of arrow III in FIG. 1. It is explanatory drawing for demonstrating the principle of an angle detector. It is a schematic block diagram which exemplifies a specific form of an angle detector, (a) is a schematic block diagram in the case where a probe light is perpendicularly incident on a measurement surface, and (b) is a schematic block diagram in which a probe light is incident on a measurement surface at a small angle of incidence. It is a schematic block diagram in the case of obliquely incident. It is explanatory drawing which illustrates the 1st movement pattern of the object to be measured when moving a probe light along a measurement line. It is explanatory drawing which illustrates the 2nd movement pattern of the object to be measured when moving a probe light along a measurement line. It is explanatory drawing for demonstrating the operation of the control unit at the time of performing the shape measurement of a measurement surface. It is explanatory drawing for demonstrating the shape derivation method in the case where there is a positional deviation between a measurement point in a reference shape and a measurement point actually measured. It is explanatory drawing which schematically showed the position and inclination angle of each measurement point on the measurement line, and the shape of the measurement surface to be derived, which are obtained by the shape derivation method of the aspect of this technique. It is a flowchart which described the outline of the shape derivation process of the measurement surface along the measurement line included in the measurement program executed by the control unit. It is explanatory drawing which contrasts and shows the process of shape measurement in the conventional shape measuring apparatus, and the process of shape measurement in the shape measuring apparatus of the aspect of this technique.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. First, the overall configuration of the shape measuring device according to the present disclosure will be outlined with reference to FIGS. 1 to 3. FIG. 1 is a schematic configuration diagram of the shape measuring device LMS, FIG. 2 is a schematic block diagram of a control system in the shape measuring device LMS, and FIG. 3 is a schematic diagram of an optical unit 20 seen in the direction of arrow III in FIG.

In order to clarify the explanation, a coordinate system including x-axis, y-axis, and z-axis that are orthogonal to each other is defined and shown in FIG. Here, the x-axis is an axis extending left and right along the paper surface, the y-axis is an axis extending back and forth through the paper surface, the z-axis is an axis extending up and down along the paper surface, and the xy plane is a horizontal plane. The z-axis corresponds to the vertical axis. For convenience of explanation, the direction shown in FIG. 1 may be referred to as the left-right direction along the x-axis, the front-back direction along the y-axis, and the up-down direction along the z-axis. The method of taking each of the y and z axes is arbitrary and does not specify the position or posture.

The shape measuring device LMS irradiates the measurement surface of the work stage unit 10 for moving the object W to be measured in each of the x, y, and z axis directions with the probe light PL, and is reflected by the measurement surface. Each part such as an optical unit 20 that measures the angle of the measurement surface based on the probe light, a head stage unit 30 that swings the optical unit 20 around the θx axis, a work stage unit 10, an optical unit 20, and a head stage unit 30. It is configured to include a control unit 50 that controls the operation of the above.

The work stage unit 10, the optical unit 20, and the head stage unit 30 are installed in an environment chamber 82 based on the base frame 81 and controlled so that the temperature and humidity are constant at predetermined values. A surface plate 85 is supported on the base frame 81 via a precision vibration isolator 83, and a work stage unit 10 is attached to the surface plate 85. Further, a gate type frame 18 straddling the work stage unit 10 is attached to the surface plate 85, and an optical unit 20 is attached to the upper beam 18b of the gate type frame 18 via the head stage unit 30.

The work stage unit 10 is mainly composed of a work holder 15 for holding the object W to be measured and a plurality of stages for moving the work holder 15 in each axial direction. That is, the work stage unit 10 moves the work holder 15 in the x-axis direction (horizontal direction), the x-stage 11, the y-axis direction (front-back direction), and the z-axis direction (vertical direction). It is composed of a z-stage 13, a θz stage 14 that rotates the work holder 15 around a θz axis (swivel axis) extending vertically, and the like.

The portal frame 18 is provided with an x sensor 41, a y sensor 42, and a z sensor 43 for detecting the x-axis direction position, the y-axis direction position, and the z-axis direction position of the work holder 15, respectively, and the detection is performed by each sensor. The position detection signal of the work holder 15 is input to the control unit 50. Further, the θz stage 14 is provided with a θz sensor 44 that detects the turning angle position of the work holder 15, and the turning angle detection signal of the work holder 15 detected by this sensor is input to the control unit 50. The x sensor 41, the y sensor 42, and the z sensor 43 can use a length measuring interferometer, a linear scale, or the like, and the θz sensor 44 can use a linear scale or a rotary encoder having a curved scale.

The optical unit 20 is provided with an angle detector 22 that irradiates the object W to be measured with the probe light PL, receives the probe light reflected by the measurement surface, and detects the angle of the measurement surface. The angle detector 22 is attached to the unit base 23 to form a measuring head 25.

FIG. 4 is an explanatory diagram for explaining the principle of the angle detector. The angle detector 22 is reflected by the light source 221 that generates the probe light, the condenser lens 222 that collects the probe light PL generated by the light source 221 and irradiates the measurement surface Ws of the object to be measured, and the measurement surface Ws. It is composed of a collimating lens 223 that collimates the probe light (referred to as reflected light) RL, a light detector 224 that detects the position of the reflected light, and the like.

The light source 221 is a laser light source that stabilizes the oscillation wavelength, light output, beam pointing, and the like, and for example, a fiber laser, a DFB semiconductor laser, or the like is used. A collimator is provided in the output unit of the light source 221, and the probe light PL converted into a parallel luminous flux is output from the light source 221. The photodetector 224 is a detector that detects the position of the reflected light RL, and for example, a QPD (Quadrant Photo Detector), a solid-state image sensor such as a CCD or CMOS can be used. In this embodiment, a configuration using QPD is shown.

In the angle detector 22, the probe light PL emitted from the light source 221 is condensed by the condenser lens 222 and incident on the measurement surface Ws. The probe light reflected by the measurement surface Ws, that is, the reflected light RL, is collimated by the collimating lens 223 and incident on the photodetector 224. With this configuration, in the angle detector 22, even if the position of the measurement surface Ws changes (shifts) in the vertical direction, the incident position of the reflected light RL incident on the photodetector 224 hardly changes. On the other hand, when the angle of the measurement surface Ws changes (tilts), the incident position of the reflected light RL incident on the photodetector 224 changes significantly. Therefore, the inclination angle of the measurement surface Ws can be calculated based on the angle detection signal output from the photodetector 224 to the control unit 50.

FIG. 5 illustrates a specific configuration of the angle detector 22. FIG. 5A is a schematic configuration diagram showing a configuration example in which the probe light PL is vertically incident on the measurement surface Ws. The same components as those of the angle detector described above are assigned the same number, and duplicate description is omitted. The angle detector 22 of this configuration example is composed of a light source 221, a polarization beam splitter 225, a quarter wavelength version 226, a condenser lens 222, a photodetector 224, and the like. The light source 221 of this configuration outputs linearly polarized probe light converted into a parallel luminous flux.

The probe light PL emitted from the light source 221 passes through the polarization beam splitter 225, is converted into circularly polarized light by the 1/4 wavelength plate 226, is condensed by the condenser lens 222, and is incident on the measurement surface Ws. The probe light reflected by the measurement surface Ws, that is, the reflected light RL, is collimated by the condenser lens 222, and is converted into linearly polarized light whose polarization surface is rotated by 90 degrees by passing through the 1/4 wavelength plate 226. Therefore, the reflected light RL is reflected by the polarizing beam splitter 225 and incident on the photodetector 224.

In the angle detector 22 of this configuration, the incident angle of the probe light incident on the measurement surface Ws is 0 degrees, that is, vertical incident, and the condenser lens 222 that concentrates the probe light PL on the measurement surface Ws collects the reflected light RL. It is configured to share the function of the collimating lens that collimates. That is, the probe light PL and the reflected light RL are transmitted through the condenser lens 222, so that the collimating lens (223) is omitted. Therefore, similarly to the angle detector 22 shown in FIG. 4, the angle of the measurement surface Ws can be detected, and the angle detector 22 can be miniaturized to make the measurement head 25 compact.

FIG. 5B is a schematic configuration diagram showing a configuration example in which the probe light PL is obliquely incident on the measurement surface Ws at a relatively small incident angle γ. Similar to the configuration form of FIG. 5A, the same components as those of the angle detector described above are assigned the same number, and duplicate description will be omitted. The angle detector 22 of this configuration example is composed of a light source 221, a condenser lens 222, a mirror 227, an aperture 228, a photodetector 224, and the like. The light source 221 outputs the probe light converted into a parallel luminous flux.

The probe light PL emitted from the light source 221 is condensed by the condenser lens 222 and obliquely incident on the measurement surface Ws at a small incident angle γ. The incident angle γ is set to about 3 to 8 degrees, for example, γ = 5 degrees. The reflected light RL reflected by the measurement surface Ws is collimated by the condenser lens 222, reflected by the mirror 227, and incident on the photodetector 224.

In the angle detector 22 of this configuration, the collimating lens (223) is omitted because the probe light is obliquely incident with a relatively small incident angle γ, and an aperture 228 is provided between the photodetector 224 and the condenser lens 222. It is configured. Therefore, similarly to the angle detector shown in FIG. 5A, the angle detector 22 can be miniaturized and the measurement head 25 can be compactly configured. Further, since the backside reflected light that may occur when the material of the object to be measured W is transparent can be effectively removed by the aperture 228 provided immediately before the light detector 224, the thickness of the object to be measured is tentatively increased. Even when it is thin or the wedge angle is small, the shape of the measurement surface can be accurately measured.

In the shape measuring device, a non-contact form of the angle detector can be used including the illustrated angle detector. In the following, for the sake of simplicity, the case where the angle detector 22 shown in FIG. 5A is used will be described as an example. At this time, the angle detector 22 is attached to the central portion of the measurement head 25 so that the optical axis of the probe optical PL intersects the θx axis 33 perpendicularly.

The head stage unit 30 includes a θx stage 35 that extends the measurement head 25 horizontally along the paper surface in FIG. 1 and swings around the θx axis (measurement axis) 33 extending in the direction perpendicular to the paper surface in FIG. Will be done. By swinging the measurement head 25 around the θx axis 33 by the θx stage 35, the probe light PL emitted from the optical unit 20 can be scanned on the measurement surface of the object W to be measured. The θx stage 35 is provided with a θx sensor 45 that detects the swing angle position of the measurement head 25, and the swing angle detection signal of the measurement head 25 detected by the θx sensor 45 is input to the control unit 50. As the θx sensor 45, a rotary encoder or a linear scale having a curved scale can be used.

The control unit 50 is output from the operation unit 51 in which the operator operates, the storage unit 52 in which the measurement program and the reference shape of the object to be measured are set and stored, the calculation unit 53 in which various calculation processes are performed, and the calculation unit 53. Based on the command signal output from the stage control unit 54 and the calculation unit 53 that control the operation of each stage 11, 12, 13, 35, 14 of x, y, z, θx, θz. It includes a measurement control unit 55 that controls the operation of the optical unit 20, an I / O unit 56 that inputs and outputs signals to and from the outside, and the like.

The operation unit 51 records on a liquid crystal display panel that displays information such as measurement programs and measurement results, a keyboard for inputting numerical values and character information, a mouse for performing selection operations, various switches, and a recording medium such as a CD or USB memory. A reader / writer that can read and write the reference shape data and measurement results of the measured surface Ws is provided, and the type of measurement surface Ws (for example, flat surface, spherical surface, aspherical surface, cylindrical, etc.) and measurement can be performed interactively. Shape measurement corresponding to patterns (radial, line, grid, etc.) can be performed.

The storage unit 52 is configured to be provided with a plurality of storage elements such as ROM and RAM. In the ROM, a control program for controlling the operation of each part of the shape measuring device LMS, a measurement program corresponding to the type of the object to be measured W and the measurement pattern, and the like are set and stored in advance. By selecting and setting the type and measurement pattern of the object to be measured W in the operation unit 51 and incorporating the corresponding measurement program into the control program, a shape measuring device suitable for measuring the shape of the object to be measured W is configured. The RAM has a reference shape (vector data of design values) of the measurement surface Ws of the object to be measured read via the reader / writer provided in the operation unit 51 or the I / O unit 56, and each of them during execution of the measurement program. Position information output from the shaft sensors 41 to 45, angle data of each measurement point output from the angle detector 22, and the like are temporarily stored.

The calculation unit 53 is composed of a CPU, a shift register, and the like, performs various calculation processes based on a control program and a measurement program preset and stored in the storage unit 52, and commands the stage control unit 54, the measurement control unit 55, and the like. A signal is output to control the operation of the work stage unit 10, the optical unit 20, and the head stage unit 30. The stage control unit 54 is driven by the x stage 11, y stage 12, z stage 13, θz stage 14, head stage unit 30, θx stage 35, etc. of the work stage unit 10 based on the command signal output from the calculation unit 53. It outputs a signal and controls the operation of each stage. The measurement control unit 55 outputs a measurement control signal to the angle detector 22 based on the command signal output from the calculation unit 53, and controls the shape measurement of the measurement surface Ws.

6 and 7 illustrate the movement pattern of the object W to be measured when the probe light PL and the object W to be measured are relatively moved to scan the probe light PL along the measurement line. Both figures schematically show the situation where the object W held in the work holder 15 is looked down from above, and the measurement lines on the measurement surface scanned by the probe optical PL are indicated _{by L 1 to} L _3. There is. FIG. 6 is an example of a movement pattern suitable for measuring an object to be measured whose surface shape of the measurement surface is axisymmetric (rotational symmetry) such as a meniscus lens and an aspherical lens. In this example, when the θx stage 35 is operated to swing the measurement head 25 and the probe light PL is moved, the x stage 11 and y are made so that the probe light PL passes through the central axis of the object W to be measured. The x-axis direction position and the y-axis direction position of the object to be measured W are aligned by the stage 12.

Then, as shown in FIG. 6 (a), from a state in which the probe light PL is irradiated to the start point SP of the measurement surface, it is scanned along the probe light PL on the measurement line L ₁ by operating the θx stage 35, measuring the angle of the measuring surface at each measurement point on the measurement line L _1. Next, as shown in FIG. 6B, the object W to be measured is rotated by a predetermined angle (for example, about 2 degrees) by the θz stage 14 to be held at the turning angle position, and the θx stage 35 is operated again. It is scanned along the probe light PL to the measurement line L _2, to measure the angle of the measuring surface at each measurement point on the measurement line L _2. Similarly, the θz stage 14 and the θx stage 35 are operated to measure the angle of the measurement surface at each measurement point along the _{measurement line L 3 ....} Then, the shape of the measurement surface along each measurement line is derived by the shape derivation method described in detail later. As a result, it is possible to obtain measurement data in which the entire measurement surface of the object W to be measured is measured in a radial shape.

FIG. 7 is an example of a movement pattern suitable for measuring a rectangular flat plate-shaped object to be measured, a cylindrical lens, or the like. In this example, the state in which the probe light PL is irradiated to the start point SP of the measurement surface, to actuate the θx stage 35 is scanned along the probe light PL on the measurement line L _1, each measured on the measurement line L ₁ Measure the angle of the measurement surface at the point. Next, the x stage 11 is operated to move the object W to be measured to the right in FIG. 7, and then the θx stage 35 is operated to _{scan the probe optical PL along the measurement line L 2} to scan the measurement line L. ₂ Measure the angle of the measurement surface for each measurement point on the top.

Similarly, the x stage 11 and the θx stage 35 are operated to measure the angle of the measurement surface at each measurement point along the _{measurement line L 3 ....} Then, the shape of the measurement surface along each measurement line is derived by the shape derivation method described in detail later. As a result, it is possible to obtain measurement data obtained by measuring the shape of the entire measurement surface of the object W to be measured in a parallel line shape. Further, after the above measurement, the object W to be measured is swiveled by a predetermined angle (for example, 90 degrees) by the θz stage 14 to be held at the swivel angle position, and the measurement surface along the measurement line is again moved by alternating the θx stage 35 and the stage 11. By performing the shape measurement of the above, it is possible to obtain the measurement data obtained by measuring the shape of the entire measurement surface in a grid pattern.

In this way, the shape measuring device LMS drives the θx stage 35 to swing the measuring head 25 around the θx axis 33, thereby scanning the probe optical PL along the measuring line. That is, the measurement lines L (L _{1 to} L _3, etc.) are formed in the y-axis direction.

The movement pattern of the object to be measured W when the probe light PL is scanned along the measurement line is not limited to the patterns shown in FIGS. 6 and 7. For example, the movement pattern may be such that the measurement line is spiral. Similar to FIG. 6, this movement pattern is also suitable for measuring an object to be measured whose surface shape of the measurement surface is axisymmetric (rotational symmetry). In this case, the θx stage 35 is operated to scan the probe light linearly from the state where the probe light is irradiated to the center of the measurement surface which is the start point SP, and the object W to be measured is continuously scanned by the θz stage 14. Rotate to. As a result, the angle of the measurement surface can be measured at each measurement point on the spiral measurement line extending from the center to the outside of the measurement surface. In the case of the spiral movement pattern, it is not necessary to stop the movement of each stage, so that the measurement time can be further shortened.

When scanning the probe light PL along the measurement line L, the control unit 50 previously sets the probe light PL to the target measurement point based on the reference shape of the measurement surface preset in the storage unit 52. The operation of the work stage unit 10 and the head stage unit 30 is controlled so as to be incident on the measurement surface Ws in a predetermined incident state. For example, when the angle detector 22 illustrated in FIG. 5A is used, the θx stage 35, so that the probe light PL emitted from the angle detector 22 is perpendicularly incident on the measurement surface Ws at a constant distance. It controls the operation of the y stage 12 and the z stage 13. In other words, the y stage 12 and the z stage so that the normal line set at the irradiation position of the probe light on the measurement surface passes through the θx axis 33 and the distance between the irradiation position and the θx axis 33 becomes the predetermined measurement distance D. 13 controls the operation.

At this time, the θx stage 35, the y stage 12, and the z stage 13 move the irradiation position in the plane including the measurement line L in the respective axial directions of the first axis, the second axis, and the third axis. This is an example of the mechanism. Further, the θx sensor 45, the y sensor 42, and the z sensor 43 are positioned to detect the position state (positional state of the work holder 15 and the angle detector 22) in the respective axial directions of the first axis, the second axis, and the third axis. This is an example of a state detector. The incident state is, for example, the angle at which the probe light PL is incident on the tangent plane at the target measurement point. In this example, the vertical incident is predetermined, but the incident angle is not limited to this.

Specifically, the control unit 50 controls the operation of the θx stage 35, the y stage 12, and the z stage 13 as follows. First, the calculation unit 53 reads out the reference shape (cross-sectional shape) of the measurement surface Ws along the measurement line set by the measurement program from the reference shape of the measurement surface Ws set and stored in the storage unit 52, and is on the measurement line. Calculate the tilt angle of each part of. Each part on the measurement line includes a measurement point and can be set at a finer pitch. Next, from the calculated tilt angle of each part, the probe light is vertically incident on the measurement surface Ws, and the swing angle position of the measurement head 25 (θx stage 35) where the distance between the θx axis 33 and the measurement point becomes the measurement distance D. , Y stage 12 and z stage 13 coordinate positions are calculated. The calculation unit 53 outputs a command signal corresponding to the calculated position state to the stage control unit 54.

The stage control unit 54 generates a drive signal based on the command signal output from the calculation unit 53, outputs the drive signal to the stages 12, 13, 35 of y, z, and θx, and outputs the drive signal to the measured object W and The measurement head 25 is relatively moved. At this time, the measurement control unit 55 outputs a measurement control signal to the optical unit 20 to emit the probe optical PL from the angle detector 22 to measure the angle of the measurement surface at each measurement point. The range irradiated with the probe light PL is, for example, a circular spot having a diameter of about 200 μm. The angle detector 22 detects the average angle around the x-axis of this spot.

FIG. 8 is an explanatory diagram schematically illustrating the state of the control, and shows a case where the measurement surface Ws has a concave aspherical shape. The measurement surface Ws in FIG. 8 shows a case where the radius of curvature of the measurement point Pwa at the axial center portion is r ₁ and the radius of curvature of the measurement points Pwb and Pwc at the peripheral portion is r _2. The calculation unit 53 reads out the reference shape of the measurement surface along the measurement line from the reference shape of the entire measurement surface Ws preset and stored in the storage unit 52, and each unit including the measurement points Pwa, Pwb, Pwc ... On the measurement line. The inclination angle of the measurement surface is calculated. Next, from the calculated tilt angle of each part, the probe light PL is vertically incident on the measurement surface, and the angle position of the θx stage 35 where the distance between the θx axis 33 and the measurement point becomes the measurement distance D, the y stage 12 and the z stage. 13 coordinate positions are calculated.

Then, the drive signal based on the calculated stage position is output to the θx stage 35, the y stage 12, and the z stage 13, and the measurement head 25 is swung and the object W to be measured is moved. If the θx stage 35, y stage 12, and z stage 13 are accurately positioned at the predetermined stage positions calculated as described above, the measurement points Pwa, Pwb, Pwc ... On the measurement line along the y-axis are included. In each part, the probe light PL emitted from the angle detector 22 vertically incidents on the measurement surface at the measurement distance D. Then, the inclination angle of each measurement point Pwa, Pwb, Pwc ... Can be calculated based on the angle detected by the angle detector 22. The angle detected by the angle detector 22 is the difference from the angle detected when the probe light PL is vertically incident, and the angle obtained by adding the swing angle of the probe light PL to the angle detected at this time is each. It is calculated as the tilt angle of the measurement points Pwa, Pwb, Pwc ...

The angle detector 22 uses a QPD as a photodetector 224, and can detect the tilt angle of the measurement surface in all directions. In this configuration example, the angle around the x-axis (inclination angle in the y-axis direction) is calculated from the angle of the measurement surface detected by the angle detector 22.

However, in reality, the θx stage 35, the y stage 12, and the z stage 13 are displaced due to a drive error or the like. Therefore, in order to accurately position each stage at the predetermined stage position, one is performed while checking the position states of the work holder 15 and the angle detector 22 detected by the θx sensor 45, the y sensor 42, and the z sensor 43. It is necessary to fine-tune the position of each stage for each measurement point and stop at the target coordinate position, which makes it difficult to quickly perform high-precision shape measurement.

Therefore, in the shape measuring device LMS, the θx sensor 45, the y sensor 42, and the z sensor are controlled so that the probe optical PL is perpendicularly incident on the measurement surface Ws at the target measurement point based on the reference shape of the object to be measured. The actual measurement point irradiated with the probe light was specified using the position and state of each moving axis detected by 43 and the reference shape of the measurement surface, and the specified actual measurement point was detected by the angle detector 22. The shape of the measurement surface is derived by applying the angle of the measurement surface. At this time, for each measurement point on the measurement line, the reference shape is reset based on the detected value of the position state of any one of the plurality of moving axes, and the actual measurement is performed based on the position state of the other two axes. Identify the point. Hereinafter, a specific configuration example will be described with respect to a method of deriving the shape of the measurement surface based on one position state detected by the detector. In addition, in this specification, a "position state" indicates a position and an angle (posture). Therefore, the "positional state in the axial direction" includes the position in the axial direction and the angle around the axis.

As described above, in measuring the shape of the measurement surface, the moving axes to be moved when scanning the probe light are the θx axis, the y-axis, and the z-axis. The position states detected for these moving axes are the swing angle position around the θx axis of the angle detector 22 detected by the θx sensor 45, and the y-axis direction of the object W to be measured detected by the y sensor 42. The position and the position in the z-axis direction of the object W to be measured detected by the z sensor 43. Here, the swing angle position around the θx axis of the angle detector 22 detected by the θx sensor 45 is equivalent to the swing angle position around the θx axis of the probe light PL. Further, the y-axis direction position of the measured object W detected by the y sensor 42 is equivalent to the y-axis direction position of the measurement surface Ws, and the z-axis direction position of the measured object W detected by the z sensor 43 is measured. It is equivalent to the position of the surface Ws in the x-axis direction.

In the shape measuring device LMS exemplified in the present embodiment, these three position states, that is, the swing angle position of the probe light PL detected by the θx sensor 45 around the θx axis, and the measurement surface Ws detected by the y sensor 42. Of the y-axis direction position and the z-axis direction position of the measurement surface Ws detected by the z sensor 43, the swing angle position around the θx axis of the probe light PL is referred to as “reference position information”. Then, the position of the reference shape is corrected in calculation based on the y-axis direction position of the measurement surface Ws detected by the y sensor 42 and the z-axis direction position of the measurement surface Ws detected by the z sensor 43, and the actual measurement is performed. Identify the point.

Hereinafter, the case where there is a positional deviation between the target measurement point and the actually measured measurement point will be described with reference to FIG. 9, which schematically shows the state. In FIG. 9, the reference shape Sa in which the target measurement point is set is shown by a thin solid line, the reset reference shape Sb is shown by a dotted line, and the actually measured measurement surface Sc (Ws) is shown by a thick solid line. In addition, in order to clarify the explanation, the positional deviation of each axis is largely shown in FIG.

_{First, the swing angle θ x 1} around the θx axis of the probe light PL, the y-axis direction position of the measurement surface Ws, and the x-axis direction of the measurement surface Ws so that the probe light PL is vertically incident on the target measurement point P _1. The position is set. Then, the operation of each stage is controlled and the measurement surface Ws is irradiated with the probe light PL, but there is an angle shift in the actual swing angle of the probe light PL, and the position shift is in the moving position of the measurement surface Ws. Exists. In FIG. 9, the swing angle of the probe light when the probe light PL is vertically incident on _{the target measurement point P 1 is θ x 1} , but the actual swing angle detected by the θx sensor 45 is θ x ₁ ′. It is different from the set angle. Further, the y-axis direction position and the x-axis direction position of the measurement surface Ws are also different from the set positions. Therefore, if there is no such positional deviation, the probe light PL _{vertically incidents on the target measurement point P 1} , but the actual incident position is P ₁ ′ and the incident angle also deviates from the vertical.

In the shape measuring device LMS, the swing angle position around the θx axis of the probe light PL detected by the θx sensor 45 is referred to as “reference position information”. Then, the reference shape Sb shown by the dotted line is reset so that the probe light PL having the actual swing angle θ x ₁ ′ is incident on the initially targeted measurement point (target measurement point) P _1b. In other words, the reference shape is positioned at the position where the probe light PL having the actual swing angle θ x _{1 ′ is incident on the target measurement point P 1b} , and the virtual reference shape Sb is set. _{Let P 1b} (y _1b , z _1b ) be the position of the target measurement point P _{1b in the reset reference shape Sb.}

Further, the calculation unit 53 has a target measurement point on the actual measurement surface Sc from the y-axis direction position of the measurement surface Ws detected by the y sensor 42 and the z-axis direction position of the measurement surface Ws detected by the z sensor 43. _Find the position of P 1c. _{Let P 1c} (y _1c , z _1c ) be the position _{of the target measurement point P 1c} on the actual measurement surface Sc obtained at this time. Next, the calculation unit 53 calculates _{the distance between the target measurement point P 1b} and the target measurement point P _1c in the y-axis direction Δy ₁ = y _1b −y _{1c and the distance Δz 1} = z _1b −z _1c in the z-axis direction. .. _{Then, the position of the target measurement point P 1c} on the actual measurement surface Sc (Ws) _{, the calculated interval Δy 1} in the y-axis direction _{and the interval Δz 1 in the} z-axis direction, and the actual swing angle θx of the probe light PL. _{From 1 ′, the actual measurement point P 1} ′ (y ₁ ′, z ₁ ′) to which the probe light PL is irradiated on the measurement surface Sc is specified.

_{Then, the angle α 1} detected by the angle detector 22 is corrected based on the inclination angle in the reference shape of the specified measurement point P ₁ ′ (y ₁ ′, z ₁ ′), and the corrected angle α ₁ ′ is corrected. Ask for. Actual measurement points P ₁ 'inclination angle beta ₁ of the angle alpha _1' after the correction is' by adding the β ₁ = _{α 1} 'swing angle [theta] x ₁ probe light calculated by + [theta] x _1'.

Similarly, for each measurement point P _n (y _n , z n), (n = _{1 to m ), the reference shape Sb is reset with the swing angle θ x n} ′ of the probe light PL as the “reference position information”. _{Further, the position P n} ′ (y _n ′, z _n ′) of the actual measurement point irradiated with the probe light is obtained based on the y-axis direction position of the measurement surface Ws and the z-axis direction position of the measurement surface Ws. .. And by correcting the detected angle alpha _n 'seek, angle alpha _n' after the correction angle alpha _n corrected by the angle detector 22 adds the swing angle [theta] x _n 'of the probe light (β _n = _{α n} ′ + _{θ x n} ′) to obtain the tilt angle of each measurement point.

And the inclination angle beta _n 'position y _n in the y-axis direction' the obtained corrected measurement point P _n is' position status data P _n 'of the measuring point P _n (y _n', beta _n) as the storage unit It is recorded in the RAM of 52. _{The position state data P n} ′ (y _n ′ β _n ) recorded in the RAM of the storage unit 52 is as follows.
P ₁ ′ (y ₁ ′, β ₁ )
P ₂ ′ (y ₂ ′, β ₂ )
P ₃ ′ (y ₃ ′, β ₃ )
・
・
・
P _m ′ (y _m ′, β _m )

The calculation unit 53 performs calculation processing from the obtained position y _n ′ of each measurement point in the y-axis direction and the inclination angle β _n by using a known method such as integration processing or fitting processing, and the dotted line is shown in FIG. The shape of the measurement surface Ws along the measurement line shown by is derived. Specifically, it can be derived as follows.

_{Now, let z 01} be the position of the measurement point P ₁ ′ with respect to the virtual measurement point P ₀ ′ in the z-axis direction. At this time, measurement for the position of the z-axis direction z _12, z-axis position z ₂₃ 'of the measuring point P _3' with respect to the measurement point P _2, the measurement point P ₃ 'of the' measurement point P ₂ 'with respect to the measurement point P _{1 The position z 34} ... Of the point P ₄ ′ in the z-axis direction is calculated as follows.
z ₁₂ = z ₀₁ + tan {(β ₁ + β ₂ ) / 2} × (y ₂ ′ − y ₁ ′)
z ₂₃ = z ₁₂ + tan {(β ₂ + β ₃ ) / 2} × (y ₃ ′ − y ₂ ′)
z ₃₄ = z ₂₃ + tan {(β ₃ + β ₄ ) / 2} × (y ₄ ′ − y ₃ ′)
・
・
・

_{Here, by setting the position z 01} of the measurement point P ₁ ′ in the z-axis direction to a predetermined value (for example, zero) _{in the above equation, z 12} , z ₂₃ , z ₃₄ ... Are sequentially obtained, and the measurement point P ₁ ′ is sequentially obtained. , P ₂ ′, P ₃ ′… The coordinate positions are obtained. Then, the shape of the measurement surface Ws is derived by connecting each of these measurement points and performing an appropriate fitting process.

As described above, in the shape measuring device of the present embodiment, the timing of acquiring data from each sensor needs to be in a state where _{the swing angle of the probe optical PL completely matches the target swing angle θ x 1.} It suffices if it is in the vicinity region including θ x _1. For example, "can be a, the swing angle [theta] x _1" has been [theta] x ₁ of the swing angle [theta] x ₁ near the probe light detected by the [theta] x sensor 45 y-axis direction position y ₁ ", z-axis direction when the position z ₁ only to be obtained as a set ", the angle alpha ₁ of the measurement surface". At this time, by the swing angle is the [theta] x ₁ "and" reference position information ", by applying the above-described method The shape of the measurement surface can be derived.

With such a configuration, it is possible to acquire data at each measurement point without stopping any of the three moving axes that relatively move the measurement surface and the probe light. Incidentally, the vicinity area including the measurement point of the target is a swing angular position [theta] x ₁ is 10 degrees of the probe light PL at the time of vertically incident probe light, for example, in the measurement points _{P 1, θx 1, θx 2} , θx _When the angle pitch of 3 ... is 1 degree, the swing angle θ x ₁ ′ of _{the probe light PL at the time of measurement is about θ x 1} ′ = 10 ± 0.1 degrees (angle between adjacent measurement points). It can be about 1/10 of the pitch).

Next, regarding the more specific flow of the measurement surface Ws shape derivation method outlined above, the measurement surface shape derivation process KP along the measurement line included in the measurement program executed by the control unit 50 is described. This will be described with reference to FIG. 11 which describes the outline.

When the measurement line of the object to be measured is specified and the shape derivation process KP of the measurement surface Ws along the measurement line is started, first, in step S1, the reference shape of the measurement surface along the measurement line from the RAM of the storage unit 52 and the reference shape of the measurement surface along the measurement line. _{The position coordinates P n} (y _n , z _n ) of the target measurement point set on the measurement line are read out. In step S3, n at the measurement point Pn is reset and n = 0 is substituted in the calculation unit 53. In step S5, the measurement control unit 55 outputs a signal to turn on the probe light to the angle detector 22, and the angle measurement of the measurement surface is started. In step S7, n = n + 1 is substituted and a target measurement point is set. In the first flow, the target measurement point is P ₁ (the first flow will be described in the same manner below).

_{In step S10, the swing angle θ x 1} of the probe light PL when the probe light is vertically incident on the target measurement point P ₁ set in step S7, the y-axis direction position y _{1 of} the measurement surface, and z of the measurement surface. The axial position z _{1 and the} like are calculated by the calculation unit 53.

In step S20, the drive signal corresponding to the position state of each axis calculated in step S10 is output from the stage control unit 54 to the θx stage 35, the y stage 12, and the z stage 13, and the probe light is scanned along the measurement line. Will be done.

In step S30, when the swing angle [theta] x of the probe light PL is detected by the [theta] x sensor 45 is in the vicinity area including the [theta] x _1, swing angle [theta] x ₁ to [theta] x sensor 45 has detected ', y sensor 42 detects The y-axis direction position y ₁ ′, the z-axis direction position z _{1 ′ detected by the z sensor 43, and the angle α 1 of the} measurement surface detected by the angle detector 22 are acquired and temporarily recorded in the RAM of the storage unit 52. At this time, the information temporarily recorded in the RAM of the storage unit 52 is P ₁ ′ (y ₁ ′, z ₁ ′, θx ₁ ′, α ₁ ). The timing of acquiring data from each sensor in step S30 does not have to be a state in which the _{swing angle detected by the θx sensor 45 completely matches θx 1,} and it may be in the vicinity region including _{θx 1.} Then, 'y-axis direction position y ₁ when the' swinging angle detected by the [theta] x sensor 45 is [theta] x _1, z-axis direction position z ₁ if ', the angle alpha ₁ of the measuring surface' is acquired as the data set good.

In step S40, the calculation unit 53 resets the reference shape Sb using _{the swing angle θ x 1 ′ detected by the θx sensor 45 as the reference position information.} That is, the reference shape Sb is positioned at a position where the probe light PL having a swing angle θ x _{1 ′ is incident on the target measurement point P 1.} Then, the position P _1b (y _1b , z _1b ) of the target measurement point P _1b in the reset reference shape Sb is calculated. The calculated position P _1b (y _1b , z _1b ) is temporarily recorded in the RAM of the storage unit 52.

In step S50, the position P _1c (y _1c , _{) of the target measurement point P 1c} on the actual measurement surface Sc is based on the y-axis direction position detected by the y sensor 42 and the z-axis direction position detected by the z sensor 43. z _1c ) is calculated. The calculated position P _1c (y _1c , z _1c ) is temporarily recorded in the RAM of the storage unit 52.

In step S60, from the position P _1b (y _1b , z _{1b ) of the target measurement point P 1b} calculated in step S40 and the position P _1c (y _1c , z _1c ) of the target measurement point P _{1c calculated in step S50. , The distance Δy 1 in} the y-axis direction _{and the distance Δz 1} in the z-axis direction of the two target measurement points P _1b and P _1c are calculated. Then, from the position of the target measurement point P _1c on the actual measurement surface, the y-axis direction interval Δy ₁ and the z-axis direction interval Δz _1, and the actual swing angle θ x ₁ ′ of the probe optical PL, the measurement surface Sc. _{The actual measurement point P 1} ′ (y ₁ ′, z ₁ ′) to which the probe light PL is irradiated is specified.

_{In step S70, the angle α 1} detected by the angle detector 22 is corrected based on the inclination angle of the reference shape of the actual measurement point position P ₁ ′ (y ₁ ′, z _{1 ′) specified in step S60.} Te 'seek, the angle alpha _1' after the correction angle alpha ₁ of the corrected finding the inclination angle beta ₁ of 'measurement point P ₁ by adding the' swing angle [theta] x ₁ probe light. In step S72, 'y-axis direction position, and the measurement point P ₁ obtained in step S70' actual measurement point P ₁ specified in step S60 the inclination angle beta ₁ of the position status data of the measuring points P ₁ ' It is recorded in the RAM of the storage unit 52 as _{P 1} ′ (y ₁ ′, β _1).

In step S75, it is determined whether or not n of the measurement point Pn is n = m, which is the last measurement point set in step S1, and if n = m, the process proceeds to step S80 and n ≠ m. If is, the process returns to step S7. As a result, the position state data P _m ′ (y _m ′, β _n ) is recorded in the RAM of the storage unit 52 for a plurality of measurement points P _n = P _{1 to} P _{m set on the measurement line.}

In step S80, the calculation unit 53 calculates the position coordinates of _{each measurement point P n ′ based on the position state data P m} ′ (y _m ′, β _n ) of the plurality of measurement points recorded in the RAM in step S72. The shape of the measurement surface along the measurement line is derived. The shape of the derived measurement surface is recorded in the RAM of the storage unit 52. Further, the shape of the measurement surface derived according to the setting is displayed on the liquid crystal display panel of the operation unit 51, or is output to a printer, a USB memory, an external computer, etc. via the I / O unit 56, and is designated. The process of deriving the shape of the measurement surface along the measurement line KP is completed.

The calculation unit 53 sets up the shape measurement along the next measurement line according to the measurement program, returns to step S1, and executes the shape derivation of the measurement surface along the next measurement line.

In the shape measuring device LMS described above, in order to make the probe light of the angle detector 22 incident on the measurement surface in a predetermined incident state, the measurement surface and the probe light are relatively moved in the surface including the measurement line. The θx stage 35, y stage 12, and z stage 13 are synchronously controlled. The positional state of these stages is detected by the θx sensor 45, the y sensor 42, and the z sensor 43.

In the above example, the movement of each stage, the detection by each sensor, the identification of the actual measurement point, and the correction of the detection angle were continuously performed for one measurement point, but all the measurement points. After moving each stage and detecting with each sensor, the actual measurement points may be specified and the detection angles may be corrected for all the measurement points. In this case, a determination as to whether or not it is the last measurement point corresponding to step S75 is provided between steps S30 and S40, and step S75 itself is omitted. Further, the movement of each stage in step S20, the detection by each sensor in step S30, the identification of the actual measurement point from step S40 to step S72, and the correction of the detection angle may be processed in parallel.

_{When measuring the angle of the measurement surface at the measurement points P 1} , P ₂ , P ₃ ... On the measurement line by moving the three stages in this way, the three positional states conventionally detected by the sensors of each stage. The angle of the measurement surface was measured by the angle detector after all of the above were in a state that matched the position and state of the target measurement point. FIG. 12A shows the relationship between the movement of the stage and the angle measurement at the measurement point in the conventional shape measurement. The vertical axis in the figure is the moving speed of an arbitrary stage (for example, θx stage), and the horizontal axis is time. To measure the angle of the measurement surface for measurement points P ₁ , P ₂ , P ₃ , etc., each measurement point is accelerated, moved, and decelerated, paused at the target position, and then the other two stages. The angle of the measurement surface is measured after the position states of all the stages including the above have reached the target position states.

FIG. 12B shows the relationship between the movement of the stage and the angle measurement at the measurement point in the shape measuring device LMS according to the present disclosure. The vertical axis and the horizontal axis in the figure are the same as those in FIG. 12 (a). In the shape measuring device LMS, _{when measuring the angle of the measuring surface for the measuring points P 1} , P ₂ , P ₃ ... On the measuring line by moving three stages, each is in the vicinity region including the target measuring point. The position state of the stage is detected, and the reference shape is determined based on the position state of any one of the three detected position states (in the embodiment, the swing angle θxn'of the probe light detected by the θx sensor 45). Reset. Then, the actual measurement point is specified from the position state detected by the other two sensors, and the angle of the measurement surface detected by the angle detector is applied to the actual measurement point to obtain the shape of the measurement surface. Derived.

That is, the shape measuring device LMS simultaneously acquires three position states when one of the three position states that specify the measurement point is in the vicinity region including the target position state, and one of them. Based on one, the actual measurement point is specified from the other two positional states and the reference shape, and the shape of the measurement surface is derived. At this time, it is not necessary that the target position state and the actual position state match. Therefore, as shown in FIG. 12 (b), _{the angle measurement of the measurement points P 1} , P ₂ , P ₃ ... Can be performed while moving any stage without pausing. As a result, the shape of the measurement surface can be obtained in a shorter time than before, not only when the measurement points are set at the same measurement pitch as before, but also when a large number of measurement points are set at a finer pitch than before. Can be measured. Therefore, according to the shape measuring device LMS and the shape measuring method of the present disclosure, highly accurate shape measurement can be performed at high speed.

In the embodiment described above, the three position states detected when the irradiation position of the probe light is moved in the plane including the measurement line, that is, the θx axis of the probe light detected by the θx sensor 45. Of the swing angle position, the y-axis direction position of the measurement surface detected by the y sensor 42, and the z-axis direction position of the measurement surface detected by the z sensor 43, the swing of the probe light detected by the θx sensor 45. The configuration using the angular position as the reference position information was explained. However, the reference position information may be in another position state, and may be, for example, the position in the z-axis direction of the measurement surface detected by the z sensor 43.

Further, in order to scan the probe light by incidenting it on the measurement surface in a predetermined incident state, the y-axis in the plane including the measurement line is set as the moving axis 3 for moving the probe light in the plane including the measurement line. And, movement in the z-axis direction and swing around the θx axis perpendicular to the surface including the measurement line are specified, and the measurement surface is moved in the y-axis and z-axis directions to swing the probe light around the θx axis. Was exemplified. However, how to move the measurement surface and the probe light can be appropriately set according to the configuration of the shape measuring device. For example, a configuration in which the probe light is fixed and the measurement surface is moved in three axial directions (y-axis direction, z-axis direction, and around the θx axis), or the probe light is moved in the z-axis direction to move the measurement surface in the y-axis direction and It can be configured to move around the θx axis, and the same effect can be obtained by applying the present technology even in such a configuration.

The present technology can also have the following configurations.
(1) A work holder that holds the object to be measured and
An angle detector that irradiates the measurement surface of the object to be measured with probe light and detects the angle of the measurement surface based on the probe light reflected by the measurement surface.
A position state detector that detects the position state of the work holder and the angle detector,
The positions of the work holder and the angle detector are controlled by the angle detector so that the probe light is incident on the target measurement point on the measurement surface in a predetermined incident state. A control unit for deriving the shape of the measurement surface based on the detected angle of the measurement surface is provided.
The control unit uses the position state of the workholder and the angle detector detected by the position state detector and a preset reference shape of the measurement surface to irradiate the measurement surface with the probe light. A shape measuring device for deriving the shape of the measuring surface by specifying the actual measuring point of the above and applying the angle of the measuring surface detected by the angle detector to the identified actual measuring point.

(2) Irradiation position moving mechanism that moves the probe light to irradiate the measurement surface in the respective axial directions of the first axis, the second axis, and the third axis by relatively moving the work holder and the angle detector. Equipped with
The position state detector detects the position state of the first axis, the second axis, and the third axis in each axial direction.
The control unit resets the reference shape based on any one of the position states of the first axis, the second axis, and the third axis detected by the position state detector, and further sets the other. The shape measuring device according to (1) above, which identifies the actual measurement point based on the positional state of the two axes.

(3) The angle detector can rotate around the first axis and can rotate around the first axis.
The work holder is movable in the second axis direction and the third axis direction, and is movable.
The position state detector detects the angular position of the angle detector as the position state in the first axis direction, and detects the moving position of the work holder as the position state in the second axis and the third axis direction. death,
The shape measuring device according to (2) above, wherein the control unit is based on the position state in the first axial direction.

(4) A plurality of target measurement points are provided along a preset measurement line.
The control unit controls the positions of the workholder and the angle detector so that the angle detector continuously detects the plurality of target measurement points (1) to (3). The shape measuring device according to any one of.

(5) For each of the plurality of target measurement points, the angle detector detects the angle, the control unit identifies the actual measurement point, and the angle to the specified actual measurement point. The shape measuring device according to (4) above, which applies a detection angle by a detector.

(6) With respect to the plurality of target measurement points After the angle detector detects the angle of each measurement point, the control unit identifies and specifies the actual measurement point with respect to the plurality of target measurement points. The shape measuring device according to (4) above, wherein the detection angle by the angle detector is applied to each actual measurement point.

(7) The angle detection by the angle detector for the plurality of target measurement points, the identification of the actual measurement points for the plurality of target measurement points by the control unit, and the specified actual measurement points. The shape measuring apparatus according to (4) above, wherein the application of the angle to the above is performed in parallel.

(8) The probe light emitted by the angle detector is in a predetermined incident state with respect to the target measurement point on the measurement surface of the object to be measured held by the work holder. To control the position of the work holder and the angle detector,
Irradiating the measurement surface with the probe light to detect the angle of the measurement surface, and
To detect the positional state of the work holder and the angle detector,
Using the detected position and state of the workholder and the angle detector and the preset reference shape of the measurement surface, the actual measurement point of the measurement surface irradiated with the probe light is specified and specified. A shape measuring method including deriving the shape of the measuring surface by applying the angle of the measuring surface detected by the angle detector to the actual measuring point.

(9) A shape measurement program for causing a computer to execute the shape measurement method according to (8) above. That is, the probe light emitted by the angle detector is in a predetermined incident state with respect to the target measurement point on the measurement surface of the object to be measured held by the work holder. Steps to control the position of the work holder and the angle detector,
The step of irradiating the measurement surface with the probe light to detect the angle of the measurement surface, and
The step of detecting the positional state of the work holder and the angle detector, and
Using the detected position and state of the workholder and the angle detector and the preset reference shape of the measurement surface, the actual measurement point of the measurement surface irradiated with the probe light is specified and specified. A shape measurement program including a step of applying the angle of the measurement surface detected by the angle detector to the actual measurement point and deriving the shape of the measurement surface.

In the shape measuring device described in (1), the shape measuring method described in (8), and the shape measuring program described in (9), the position states of the work holder and the angle detector detected by the position state detector are used. By identifying the actual measurement point irradiated with the probe light using the preset reference shape of the measurement surface, and applying the angle of the measurement surface detected by the angle detector to the specified actual measurement point. , The shape of the measurement surface is derived. Therefore, the shape of the measurement surface can be measured without positioning and stationary the object to be measured at each measurement point (in a state where the object to be measured is relatively moved with respect to the probe light). Therefore, according to the shape measuring device and the shape measuring method of the present disclosure, highly accurate shape measurement can be performed at high speed.

10 Work stage unit (irradiation position movement mechanism)
11 x stage 12 y stage 13 z stage 15 work holder 22 angle detector 30 head stage unit (irradiation position movement mechanism)
33 θx axis (1st axis)
35 θx stage 42 y sensor (position state detector)
43 z sensor (position state detector)
45 θx sensor (position state detector)
50 Control unit (control unit)
L (L _{1 to} L ₃ ) Measurement line LMS shape measuring device P ₁ , P ₂ , P ₃ … Target measurement point P ₁ ′, P ₂ ′, P ₃ ′… Actual measurement point PL probe optical KP shape derivation Process (shape measurement program that realizes shape measurement method)
W Measured object Ws Measurement surface

Claims (8)

A work holder that holds the object to be measured and
An angle detector that irradiates the measurement surface of the object to be measured with probe light and detects the angle of the measurement surface based on the probe light reflected by the measurement surface.
An irradiation position moving mechanism that moves the probe light to irradiate the measurement surface in the respective axial directions of the first axis, the second axis, and the third axis by relatively moving the work holder and the angle detector.
A position state detector that detects the position state of the work holder and the angle detector in each axis direction of the first axis, the second axis, and the third axis.

The positions of the work holder and the angle detector are controlled by the angle detector so that the probe light is incident on the target measurement point on the measurement surface in a predetermined incident state. A control unit for deriving the shape of the measurement surface based on the detected angle of the measurement surface is provided.
The control unit uses any one of the position states of the first axis, the second axis, and the third axis detected by the position state detector as a reference for the reference shape of the measurement surface set in advance. It is reset, and the actual measurement point of the measurement surface irradiated with the probe light is specified based on the positional state of the other two axes, and the inclination angle of the specified actual measurement point in the reference shape is set. based on the angle detector to correct the angle of said detected measuring surface by seeking an inclination angle of the actual measurement points, the shape measuring apparatus for deriving a shape of the measurement surface. The angle detector is rotatable around the first axis and is rotatable around the first axis.
The work holder is movable in the second axis direction and the third axis direction, and is movable.
The position state detector detects the angular position of the angle detector as the position state in the first axis direction, and detects the moving position of the work holder as the position state in the second axis and the third axis direction. death,
The shape measuring device according to claim 1, wherein the control unit is based on the position state in the first axial direction. A plurality of target measurement points are provided along a preset measurement line.
The first or second aspect of the present invention, wherein the control unit controls the positions of the work holder and the angle detector so that the angle detector continuously detects the plurality of target measurement points. Shape measuring device. For each of the plurality of target measurement points, the angle is detected by the angle detector, the actual measurement point is specified by the control unit, and the angle detector to the specified actual measurement point is used. The shape measuring device according to claim 3 , wherein the detection angle is applied. After the angle detector detects the angle of each measurement point with respect to the plurality of target measurement points, the control unit identifies the actual measurement point with respect to the plurality of target measurement points and each of the specified actual measurement points. The shape measuring apparatus according to claim 3 , wherein the detection angle by the angle detector is applied to the measurement point of the above. The angle detection by the angle detector for the plurality of target measurement points, the identification of the actual measurement points for the plurality of target measurement points by the control unit, and the identification of each of the specified actual measurement points. The shape measuring device according to claim 3 , wherein the angle is applied in parallel. The workholder is held so that the probe light emitted by the angle detector is incident on the target measurement point on the measurement surface of the object to be measured held in the workholder in a predetermined incident state. And the angle detector are relatively moved to control the positions of the probe light irradiating the measurement surface in the axial directions of the first axis, the second axis, and the third axis.
Irradiating the measurement surface with the probe light to detect the angle of the measurement surface, and
The position state detector detects the position state of the work holder and the angle detector in each axis direction of the first axis, the second axis, and the third axis .
The preset reference shape of the measurement surface is reset based on any one of the position states of the first axis, the second axis, and the third axis detected by the position state detector, and further. The actual measurement point of the measurement surface irradiated with the probe light is specified based on the positional state of the other two axes, and the angle detection is performed based on the inclination angle of the specified actual measurement point in the reference shape. A shape measuring method including correcting the angle of the measuring surface detected by the instrument to obtain the inclination angle of the actual measuring point and deriving the shape of the measuring surface. A shape measurement program for causing a computer to execute the shape measurement method according to claim 7.

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