Processing System

Abstract

This machining system includes: a mounting apparatus on which a workpiece and a reference member are mounted; a machining apparatus capable of performing irradiation of a machining beam via an objective optical system; a light detection apparatus capable of irradiating the reference member with a measurement beam via the objective optical system and capable of receiving light from the reference member; a machining head including the objective optical system; a rotation apparatus that rotates the mounting apparatus; and a calculation unit. The light detection apparatus acquires a first detection result by irradiation of the measurement beam to the reference member located at a first position, and acquires a second result by irradiation of the measurement beam to the reference member having moved to a second position. The calculation unit calculates a movement error generated in movement of at least one of the mounting apparatus and the machining head on the basis of positional information of the reference member obtained from the first and second detection results.

Description

[Technical Field]

[0001] The present invention relates to the technical field of machining systems capable of machining a workpiece, for example. [Background technology]

[0002] As a machining system capable of machining a workpiece, Patent Document 1 describes a machining device that forms a structure by irradiating a machining beam onto the surface of a workpiece. In such a machine tool, a technical challenge is to appropriately calculate movement errors. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2000 / 054925 Brochure Summary of the Invention

[0004] According to a first aspect, there is provided a processing system comprising: a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a processing device capable of irradiating the workpiece with a processing beam for processing the workpiece via an objective optical system; a photodetector capable of irradiating the reference member with a measurement beam via the objective optical system and receiving at least a portion of the light from the reference member generated by the irradiation of the measurement beam via the objective optical system; a processing head including the objective optical system; a rotation device that rotates the mounting device; and a calculation unit, wherein the photodetector obtains a first detection result by irradiating the measurement beam onto the reference member located at a first position, and obtains a second detection result by irradiating the measurement beam onto the reference member that has moved from the first position to a second position different from the first position using the rotation device; and the calculation unit calculates a movement error that occurs in the movement of at least one of the mounting device and the processing head based on position information of the reference member obtained using the first detection result and position information of the reference member obtained using the second detection result.

[0005] According to a second aspect, there is provided a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a photodetector capable of irradiating the reference member with a measurement beam for measuring the reference member via an objective optical system and receiving at least a part of light from the reference member generated by the irradiation of the measurement beam; a rotation device capable of rotating the mounting device about a first axis and about a second axis intersecting the first axis; a movement device that moves a processing head including at least the objective optical system along a movement axis; and a calculation unit, wherein the rotation device moves the reference member from an eighth position to a ninth position by rotating the mounting device about the first axis, and moves the reference member from a tenth position to an eleventh position by rotating the mounting device about the second axis; a ninth detection result is obtained by irradiating the reference member moved to the ninth position with the measurement beam via the objective optical system located at the twelfth position, a tenth detection result is obtained by irradiating the reference member located at a tenth position with the measurement beam via the objective optical system located at a thirteenth position, and an eleventh detection result is obtained by irradiating the reference member located at the eleventh position with the measurement beam via the objective optical system located at the thirteenth position or a fourteenth position different from the thirteenth position, and the calculation unit calculates a movement error occurring in movement of at least one of the placement device and the machining head based on position information of the reference member obtained using the eighth detection result, the position information of the reference member obtained using the ninth detection result, the position information of the reference member obtained using the tenth detection result, and the position information of the reference member obtained using the eleventh detection result.

[0006] According to a third aspect, there is provided a processing system comprising a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed, an optical detection device capable of irradiating a measurement beam for measuring the reference member onto the reference member via an objective optical system and capable of receiving at least a portion of the light from the reference member generated by the irradiation of the measurement beam, and a drive device for moving the mounting device, wherein the optical detection device irradiates the measurement beam onto the reference member located at an eighth position via the objective optical system located at a twelfth position, and irradiates the measurement beam onto the reference member moved to a ninth position via the objective optical system located at the twelfth position.

[0007] According to a fourth aspect, there is provided a processing system comprising: a mounting device on which a workpiece can be placed, and on which a reference member different from the workpiece can be placed; an optical detection device capable of irradiating the reference member with a measurement beam for measuring the reference member via an objective optical system and capable of receiving at least a portion of the light from the reference member generated by the irradiation of the measurement beam; and a drive device for moving the mounting device, wherein the optical detection device irradiates the measurement beam onto the reference member located at a 10th position via the objective optical system located at a 15th position, and irradiates the measurement beam onto the reference member moved to an 11th position via the objective optical system located at the 15th position, and further irradiates the measurement beam onto the reference member located at the 10th position via the objective optical system located at a 13th position, and irradiates the measurement beam onto the reference member moved to the 11th position via the objective optical system located at a 14th position.

[0008] According to a fifth aspect, there is provided a processing system comprising: a mounting device on which a workpiece can be placed, and on which a reference member different from the workpiece can be placed; an optical detection device capable of irradiating a measurement beam for measuring the reference member onto the reference member via an objective optical system and capable of receiving at least a portion of the light from the reference member generated by the irradiation of the measurement beam; and a drive device for moving the mounting device, wherein the optical detection device irradiates the measurement beam onto the reference member located at a 10th position via the objective optical system located at a 16th position, and irradiates the measurement beam onto the reference member moved to an 11th position via the objective optical system located at the 16th position, and further irradiates the measurement beam onto the reference member moved to the 11th position via the objective optical system located at a 17th position.

[0009] The functions and other advantages of the present invention will become apparent from the following detailed description of the preferred embodiments. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view that schematically shows the configuration of a processing system according to this embodiment. [Figure 2] FIG. 2 is a system configuration diagram showing the system configuration of the machining system according to this embodiment. [Figure 3] FIG. 3 is a cross-sectional view showing the configuration of the machining head in this embodiment. [Figure 4] FIG. 4 is a perspective view showing a processed shot area. [Figure 5] FIG. 5 is a perspective view showing a measurement shot area. [Figure 6] 6(a) and 6(b) are cross-sectional views showing marks formed on a workpiece for performing optical calibration operations. [Figure 7] FIG. 7 is a plan view showing a plurality of processing marks formed at a plurality of locations in the processing shot area and the measurement shot area. [Figure 8] Each of Figures 8(a) to 8(c) shows an example of the reference member. [Figure 9] 9(a) and 9(b) are cross-sectional views showing the moving reference member. [Figure 10] 10(a) and 10(b) are cross-sectional views showing a processing head that moves so as to follow a moving reference member. [Figure 11] FIG. 11 is a cross-sectional view showing a processing head that moves so as to follow a reference member that rotates around the C axis. [Figure 12] FIG. 12 is a cross-sectional view showing a processing head that moves so as to follow a reference member that rotates around the A axis. [Figure 13] FIG. 13 is a cross-sectional view showing a processing head that moves so as to follow the moving reference member. [Figure 14] FIG. 14 is a cross-sectional view showing a processing head that measures a moving reference member without moving it. [Figure 15] Each of Figures 15(a) to 15(c) shows the calculation results of the position of the reference member. [Figure 16] FIG. 16 is a flowchart showing the flow of the deformation error calculation operation. [Figure 17] 17(a) and 17(b) show a stage that rotates around the A axis. [Figure 18] Each of Figures 18(a) to 18(d) shows a moving reference member. [Figure 19] 19(a) and 19(b) each show the relationship between the distance from the processing head to the reference member and the radius of rotation of the reference member. [Figure 20] FIG. 20 shows the relationship between the distance from the processing head to the reference member and the rotation angle of the stage. [Figure 21] Each of Figures 21(a) to 21(d) shows a moving reference member. [Figure 22] 22(a) and 22(b) each show the relationship between the distance from the processing head to the reference member and the radius of rotation of the reference member. [Figure 23] FIG. 23 shows a stage that rotates around the A axis. [Figure 24] Each of Figures 24(a) and 24(b) shows a moving reference member. [Figure 25] Each of Figures 25(a) and 25(b) is a cross-sectional view showing a processing head that moves so as to follow a moving reference member. [Figure 26] FIG. 26 shows the relationship between the position (movement trajectory) of the reference member and the movement error. [Figure 27] Each of Figures 27(a) and 27(b) is a cross-sectional view showing a processing head that measures a reference member. [Figure 28] Each of Fig. 28(a) and Fig. 28(b) is a cross-sectional view showing a processing head for measuring a reference member having a curved surface and a flat surface. [Figure 29] Each of Figures 29(a) and 29(b) is a plan view showing the position of the reference member. [Figure 30] Each of Figures 30(a) and 30(b) is a cross-sectional view showing a processing head that measures a reference member. [Figure 31] Each of Figures 31(a) and 31(b) is a cross-sectional view showing a processing head that measures a reference member. [Figure 32] Each of Figures 32(a) and 32(b) is a cross-sectional view showing a processing head that measures a reference member. [Figure 33] Each of Figures 33(a) and 33(b) is a cross-sectional view showing a processing head that measures a reference member. [Figure 34] FIG. 34 is a system configuration diagram showing the system configuration of the measurement system. [Figure 35] FIG. 35 is a side view showing a modified example of the head drive system. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of a machining system, a movement error calculation system, a movement error calculation method, and a measurement system will be described with reference to the drawings. Hereinafter, embodiments of a machining system, a movement error calculation system, a movement error calculation method, and a measurement system will be described using a machining system SYS capable of machining a workpiece W, which is an example of an object. Note that, because the machining system SYS is capable of machining a workpiece W, the machining system SYS may also be called a machine tool.

[0012] In the following description, the positional relationships of the various components that make up the machining system SYS will be explained using an XYZ Cartesian coordinate system defined by mutually orthogonal X, Y, and Z axes. For ease of explanation, the X-axis and Y-axis directions are assumed to be horizontal (i.e., predetermined directions within a horizontal plane), and the Z-axis direction is assumed to be vertical (i.e., a direction perpendicular to the horizontal plane, essentially an up-and-down direction). The rotation directions around the X-axis, Y-axis, and Z-axis (in other words, tilt directions) are referred to as the θX direction, θY direction, and θZ direction, respectively. Here, the Z-axis direction may be the direction of gravity. The XY plane may also be assumed to be horizontal.

[0013] (1) Configuration of the machining system SYS First, the configuration of the machining system SYS in this embodiment will be described.

[0014] (1-1) Overall configuration of the machining system SYS First, the structure of the machining system SYS in this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view schematically showing the configuration of the machining system SYS in this embodiment. Figure 2 is a system configuration diagram showing an example of the system configuration of the machining system SYS in this embodiment.

[0015] As shown in FIGS. 1 and 2, the machining system SYS includes a machining unit 1 and a control unit 2. At least a portion of the machining unit 1 may be housed in an internal space SP of a housing 3. The internal space SP of the housing 3 may be purged with a purge gas such as nitrogen gas, or may not be purged with a purge gas. The internal space SP of the housing 3 may be evacuated, or may not be evacuated. However, the machining unit 1 does not have to be housed in the internal space SP of the housing 3. A local space surrounding only a portion of the machining unit 1 may be purged with a purge gas, or may be evacuated.

[0016] The machining unit 1 is capable of machining a workpiece W, which is an object to be machined (which may also be referred to as a base material), under the control of the control unit 2. The workpiece W may be, for example, a metal, an alloy (e.g., duralumin, etc.), a semiconductor (e.g., silicon), a resin, a composite material such as CFRP (Carbon Fiber Reinforced Plastic), paint (for example, a paint layer applied to a base material), glass, or an object made of any other material.

[0017] The machining unit 1 irradiates the workpiece W with processing light EL in order to process the workpiece W. The processing light EL may be any type of light as long as it can process the workpiece W when irradiated onto the workpiece W. In this embodiment, the explanation will be given using an example in which the processing light EL is laser light, but the processing light EL may be a type of light other than laser light. Furthermore, the wavelength of the processing light EL may be any wavelength as long as it can process the workpiece W when irradiated onto the workpiece W. For example, the processing light EL may be visible light or invisible light (e.g., at least one of infrared light, ultraviolet light, extreme ultraviolet light, etc.). The processing light EL may include pulsed light (e.g., pulsed light having an emission time of picoseconds or less). Alternatively, the processing light EL may not include pulsed light. In other words, the processing light EL may be continuous light.

[0018] The machining unit 1 may perform removal machining, which removes a portion of the workpiece W by irradiating the workpiece W with the processing light EL. For example, the machining unit 1 may perform removal machining so that the workpiece W has a desired shape. For example, the machining unit 1 may perform removal machining so that a riblet structure is formed on the surface of the workpiece W. The riblet structure may include a structure that can reduce the resistance of the surface of the workpiece W to the fluid (particularly, at least one of frictional resistance and turbulent frictional resistance). The riblet structure may include a structure that can reduce noise generated when the fluid moves relative to the surface of the workpiece W. Alternatively, in addition to or instead of removal machining, the machining unit 1 may perform additional machining, which forms a shaped object on the workpiece W by irradiating the workpiece W with the processing light EL. Alternatively, in addition to or instead of removal machining and / or additional machining, the machining unit 1 may perform machining, which processes the workpiece W by bringing a tool into contact with the workpiece W. In this case, the machining unit 1 does not need to irradiate the workpiece W with the processing light EL.

[0019] The processing unit 1 is further capable of measuring the measurement object M under the control of the control unit 2. In order to measure the measurement object M, the processing unit 1 irradiates the measurement object M with measurement light ML for measuring the measurement object M. Specifically, the processing unit 1 measures the measurement object M by irradiating the measurement light ML onto the measurement object M and detecting (i.e., receiving) at least a portion of the light from the measurement object M irradiated with the measurement light ML. The light from the measurement object M irradiated with the measurement light ML is light from the measurement object M generated by the irradiation of the measurement light ML.

[0020] The measurement light ML may be any type of light as long as it can measure the measurement object M by irradiating it onto the measurement object M. In this embodiment, the description will be given using an example in which the measurement light ML is laser light. However, the measurement light ML may be a type of light other than laser light. Furthermore, the wavelength of the measurement light ML may be any wavelength as long as it can measure the workpiece W by irradiating it onto the measurement object M. For example, the measurement light ML may be visible light or invisible light (e.g., at least one of infrared light, ultraviolet light, extreme ultraviolet light, etc.). The measurement light ML may include pulsed light (e.g., pulsed light having an emission time of picoseconds or less). Alternatively, the measurement light ML may not include pulsed light. In other words, the measurement light ML may be continuous light.

[0021] The processing unit 1 may be capable of using the measurement light ML to measure the characteristics of the measurement object M. The characteristics of the measurement object M may include, for example, at least one of the position of the measurement object M, the shape of the measurement object M, the reflectance of the measurement object M, the transmittance of the measurement object M, the temperature of the measurement object M, and the surface roughness of the measurement object M.

[0022] In the following description, an example will be described in which the processing unit 1 at least measures the position of the measurement object M. The position of the measurement object M may include the position of the surface of the measurement object M. The position of the surface of the measurement object M may include the position of at least a portion of the surface of the measurement object M. Furthermore, the position of the measurement object M may mean the position of the measurement object M with respect to the processing head 13 (i.e., the relative position). In other words, the position of the measurement object M may mean the position of the measurement object M in a measurement coordinate system based on the processing head 13. Furthermore, as will be described later, the operation of measuring the position of the measurement object M may include the operation of measuring the shape of the measurement object M. This is because the shape of the measurement object M can be calculated from the position of the measurement object M.

[0023] The measurement object M may include, for example, a workpiece W to be machined by the machining unit 1. The measurement object M may include, for example, any object placed on the stage 16. The any object placed on the stage 16 may include, for example, the workpiece W. The any object placed on the stage 16 may include a reference member FM used in the movement error calculation operation described below. The measurement object M may include, for example, the stage 16.

[0024] The machining unit 1 may measure the measurement object M during a period before machining of the workpiece W is started. In other words, the machining unit 1 may measure the measurement object M before the machining unit 1 starts machining of the workpiece W. The machining unit 1 may measure the measurement object M during a period when machining of the workpiece W is being performed. In other words, the machining unit 1 may perform machining of the workpiece W and measurement of the measurement object M in parallel. The machining unit 1 may measure the measurement object M during a period after machining of the workpiece W is completed. In other words, the machining unit 1 may measure the measurement object M after the machining unit 1 has completed machining of the workpiece W.

[0025] In order to process the workpiece W and measure the measurement object M, the processing unit 1 is equipped with a processing light source 11, a measurement light source 12, a processing head 13, a head drive system 14, a position measurement device 15, a stage 16, a stage drive system 17, and a position measurement device 18.

[0026] The processing light source 11 generates processing light EL. When the processing light EL is laser light, the processing light source 11 may include, for example, a laser diode. Furthermore, the processing light source 11 may be a light source capable of pulse oscillation. In this case, the processing light source 11 can generate pulsed light (for example, pulsed light having an emission time of picoseconds or less) as the processing light EL. Note that the processing light source 11 may also be a CW (continuous wave) light source that generates CW.

[0027] The measurement light source 12 generates the measurement light ML. When the measurement light ML is a laser beam, the measurement light source 12 may include, for example, a laser diode. Furthermore, the measurement light source 12 may be a light source capable of pulse oscillation. In this case, the measurement light source 12 can generate pulsed light (for example, pulsed light having an emission time of picoseconds or less) as the processing light EL. Note that the measurement light source 12 may also be a CW (continuous wave) light source that generates CW.

[0028] The machining head 13 irradiates the workpiece W with the machining light EL generated by the machining light source 11 and the measurement light ML generated by the measurement light source 12, and irradiates the measurement object M with the measurement light ML. In order to irradiate the workpiece W with the machining light EL and the measurement object M with the measurement light ML, the machining head 13 is equipped with a machining optical system 131, a measurement optical system 132, a combining optical system 133, and an objective optical system 134. The machining head 13 irradiates the workpiece W with the machining light EL via the machining optical system 131, the combining optical system 133, and the objective optical system 134. The machining head 13 also irradiates the measurement light ML onto the measurement object M via the measurement optical system 132, the combining optical system 133, and the objective optical system 134. The structure of the machining head 13 will be described in detail later with reference to FIG. 3.

[0029] The head drive system 14 moves the machining head 13. The head drive system 14 may, for example, move the machining head 13 (i.e., move linearly) along a movement axis along at least one of the X-axis direction, the Y-axis direction, and the Z-axis direction. In this case, the head drive system 14 may be referred to as a movement device. The head drive system 14 may, for example, move the machining head 13 along at least one of the θX direction, the θY direction, and the θZ direction in addition to or instead of at least one of the X-axis direction, the Y-axis direction, and the Z-axis direction. In other words, the head drive system 14 may rotate (i.e., rotationally move) the machining head 13 around at least one of the rotation axis along the X-axis direction, the rotation axis along the Y-axis direction, and the rotation axis along the Z-axis direction. In this case, the head drive system 14 may be referred to as a rotation device. In the following description, the rotation axis along the X-axis direction, the rotation axis along the Y-axis direction, and the rotation axis along the Z-axis direction will be referred to as the A-axis, the B-axis, and the C-axis, respectively. In this embodiment, an example will be described in which the head drive system 14 moves the processing head 13 along each of the X-axis direction, the Y-axis direction, and the Z-axis direction. The head drive system 14 may also be referred to as a drive device.

[0030] When the head drive system 14 moves the machining head 13, the relative positional relationship between the machining head 13 and a stage 16 (described later) (and further, a workpiece W placed on the stage 16) changes. As a result, the relative positional relationship between a processing shot area PSA (see FIG. 4 described later) where the machining head 13 performs processing and the workpiece W changes. In other words, the processing shot area PSA moves with respect to the workpiece W. The machining unit 1 may process the workpiece W while moving the machining head 13. Specifically, the machining unit 1 may set the processing shot area PSA at a desired position on the workpiece W by moving the machining head 13, and process the desired position on the workpiece W. However, if the processing shot area PSA can be set at a desired position on the workpiece W by moving the stage 16 described later, the machining unit 1 may process the workpiece W without moving the machining head 13.

[0031] Furthermore, when the head drive system 14 moves the processing head 13, the relative positional relationship between the measurement shot area MSA (see FIG. 4 described later) where the processing head 13 performs measurement and the measurement object M placed on the stage 16 changes. In other words, the measurement shot area MSA moves with respect to the measurement object M. The processing unit 1 may measure the measurement object M while moving the processing head 13. Specifically, the processing unit 1 may set the measurement shot area MSA at a desired position on the measurement object M by moving the processing head 13, and measure the desired position on the measurement object M. However, if the measurement shot area MSA can be set at the desired position on the measurement object M by moving the stage 16 described later, the processing unit 1 may measure the measurement object M without moving the processing head 13.

[0032] The position measurement device 15 can measure the position of the machining head 13. The position measurement device 15 may include, for example, an interferometer (e.g., a laser interferometer). The position measurement device 15 may include, for example, an encoder (for example, at least one of a linear encoder and a rotary encoder). When the head drive system 14 uses a stepping motor as a drive source, the position measurement device 15 may include, for example, an open-loop control position detection device. The open-loop control position detection device is a position detection device that measures the position of the machining head 13 by estimating the amount of movement of the machining head 13 from the integrated value of the number of pulses used to drive the stepping motor.

[0033] The workpiece W is placed on the stage 16. For this reason, the stage 16 may be referred to as a placement device. Specifically, the workpiece W is placed on a placement surface 161 of the stage 16. In the example shown in FIG. 1, the placement surface 161 is a surface that intersects with the Z axis. The stage 16 is capable of supporting the workpiece W placed on the stage 16. The stage 16 may also be capable of holding the workpiece W placed on the stage 16. In this case, the stage 16 may be equipped with at least one of a mechanical chuck, an electrostatic chuck, a vacuum chuck, or the like to hold the workpiece W.

[0034] A measurement object M may be placed on the stage 16. Specifically, the measurement object M is placed on a placement surface 161 of the stage 16. The stage 16 is capable of supporting the measurement object M placed on the stage 16. The stage 16 may be capable of holding the measurement object M placed on the stage 16. In this case, the stage 16 may include at least one of a mechanical chuck, an electrostatic chuck, a vacuum chuck, or the like in order to hold the measurement object M.

[0035] The stage 16 is disposed at a position that allows it to face the processing head 13. In the example shown in Fig. 1, the stage 16 is disposed below the processing head 13. However, the stage 16 may be disposed at a position different from the position below the processing head 13.

[0036] The stage drive system 17 moves the stage 16. The stage drive system 17 may move the stage 16 along a movement axis along at least one of the X-axis direction, the Y-axis direction, and the Z-axis direction, for example. In this case, the stage drive system 17 may be referred to as a movement device. The stage drive system 17 may move the stage 16 along at least one of the θX direction, the θY direction, and the θZ direction, in addition to or instead of at least one of the X-axis direction, the Y-axis direction, and the Z-axis direction. That is, the stage drive system 17 may rotate (i.e., rotationally move) the stage 16 around at least one of the rotation axis along the X-axis direction (i.e., the A-axis), the rotation axis along the Y-axis direction (i.e., the B-axis), and the rotation axis along the Z-axis direction (i.e., the C-axis). In this case, the stage drive system 17 may be referred to as a rotation device. In this embodiment, an example will be described in which the stage drive system 17 rotates the stage 16 around each of the rotation axes of the A-axis and the C-axis. The stage drive system 17 may also be referred to as a drive device.

[0037] When the stage 31 moves, the mounting surface 161 of the stage 16 also moves. Therefore, the operation of moving the stage 31 may include the operation of moving the mounting surface 161. Furthermore, if the stage 31 is supported by another support member, the stage 31 may move in conjunction with the movement of the support member that supports the stage 31. In other words, the operation of moving the stage 31 may include the operation of moving the stage 31 by moving the support member that supports the stage 31.

[0038] When the stage drive system 17 moves the stage 16, the relative positional relationship between the machining head 13 and the stage 16 (and further, the workpiece W placed on the stage 16) changes. As a result, the relative positional relationship between the workpiece W and a processing shot area PSA (see FIG. 4 described later) where the machining head 13 performs processing changes. In other words, the processing shot area PSA moves relative to the workpiece W. The machining unit 1 may process the workpiece W while moving the stage 16. Specifically, the machining unit 1 may set the processing shot area PSA at a desired position on the workpiece W by moving the stage 16, and process the desired position on the workpiece W. However, if the processing shot area PSA can be set at a desired position on the workpiece W by moving the above-mentioned machining head 13, the machining unit 1 may process the workpiece W without moving the stage 16.

[0039] Furthermore, when the stage drive system 17 moves the stage 16, the relative positional relationship between the measurement shot area MSA (see FIG. 4 described later) where the processing head 13 performs measurement and the measurement object M placed on the stage 16 changes. That is, the measurement shot area MSA (see FIG. 4 described later) moves with respect to the measurement object M. The processing unit 1 may measure the measurement object M while moving the stage 16. Specifically, the processing unit 1 may set the measurement shot area MSA at a desired position on the measurement object M by moving the stage 16, and measure the desired position on the measurement object M. However, if the measurement shot area MSA can be set at the desired position on the measurement object M by moving the processing head 13 described above, the processing unit 1 may measure the measurement object M without moving the stage 16. Note that the operation of setting the measurement shot area MSA at a desired position on the measurement object M may be considered equivalent to the operation of positioning the measurement shot area MSA in a desired range on the surface of the measurement object M.

[0040] The position measurement device 18 can measure the position of the stage 16. The position measurement device 18 may include, for example, an interferometer (e.g., a laser interferometer). The position measurement device 18 may include, for example, an encoder (at least one of a linear encoder and a rotary encoder, as an example). When the stage drive system 17 uses a stepping motor as a drive source, the position measurement device 18 may include, for example, an open-loop control position detection device. The open-loop control position detection device is a position detection device that measures the position of the stage 16 by estimating the amount of movement of the stage 16 from the integrated value of the number of pulses used to drive the stepping motor.

[0041] The control unit 2 controls the operation of the machining unit 1. The control unit 2 may also be referred to as a control unit. For example, the control unit 2 may control the operation of the machining head 13 provided in the machining unit 1. For example, the control unit 2 may control the operation of at least one of the machining optical system 131, the measurement optical system 132, the synthesis optical system 133, and the objective optical system 134 provided in the machining head 13. For example, the control unit 2 may control the operation of the head drive system 14 provided in the machining unit 1 (for example, the movement of the machining head 13). For example, the control unit 2 may control the operation of the stage drive system 17 provided in the machining unit 1 (for example, the movement of the stage 16).

[0042] The control unit 2 may control the operation of the machining unit 1 based on the measurement results of the measurement object M by the machining unit 1. Specifically, the control unit 2 may generate measurement data of the measurement object M (e.g., data related to at least one of the position and shape of the measurement object M) based on the measurement results of the measurement object M, and control the operation of the machining unit 1 based on the generated measurement data. For example, the control unit 2 may generate measurement data of at least a portion of the workpiece W (e.g., calculate at least one of the position and shape of at least a portion of the workpiece W) based on the measurement results of the workpiece W, which is an example of the measurement object M, and control the operation of the machining unit 1 to machine the workpiece W based on the measurement data. As an example, the control unit 2 may control the operation of the machining unit 1 based on the measurement data so that a processing shot area PSA to be irradiated with processing light EL is set to a desired position on the workpiece W.

[0043] In this embodiment, the control unit 2 may perform a movement error calculation operation to calculate a movement error (in other words, a motion error) occurring in the movement of at least one of the machining head 13 and the stage 16, based on the measurement results by the machining unit 1. Specifically, the control unit 2 may perform the movement error calculation operation based on the measurement results of a reference member FM, which will be described later, by the machining unit 1. The control unit 2 that performs the movement error calculation operation may be referred to as a movement error calculation system. The movement error calculation operation will be described in detail later with reference to FIG. 11 etc.

[0044] The control unit 2 may include, for example, an arithmetic device and a storage device. The control unit 2 may also be referred to as a calculation unit. The arithmetic device may include, for example, at least one of a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The storage device may include, for example, a memory. The control unit 2 functions as a device that controls the operation of the machining unit 1 by the arithmetic device executing a computer program. This computer program is a computer program for causing the arithmetic device to perform (i.e., execute) the operations to be performed by the control unit 2, which will be described later. In other words, this computer program is a computer program for causing the control unit 2 to function so as to cause the machining unit 1 to perform the operations to be performed later. The computer program executed by the arithmetic device may be recorded in a storage device (i.e., a recording medium) included in the control unit 2, or may be recorded in any storage medium (e.g., a hard disk or semiconductor memory) built into or externally attachable to the control unit 2. Alternatively, the arithmetic device may download the computer program to be executed from a device external to the control unit 2 via a network interface.

[0045] The control unit 2 does not have to be provided inside the machining unit 1. For example, the control unit 2 may be provided outside the machining unit 1 as a server or the like. In this case, the control unit 2 and the machining unit 1 may be connected via a wired and / or wireless network (or a data bus and / or a communication line). As the wired network, a network using a serial bus interface, such as at least one of IEEE1394, RS-232x, RS-422, RS-423, RS-485, and USB, may be used. As the wired network, a network using a parallel bus interface may be used. As the wired network, a network using an interface compliant with Ethernet (registered trademark), such as at least one of 10BASE-T, 100BASE-TX, and 1000BASE-T, may be used. As the wireless network, a network using radio waves may be used. An example of a network using radio waves is a network compliant with IEEE802.1x (for example, at least one of wireless LAN and Bluetooth (registered trademark)). A network using infrared rays may be used as the wireless network. A network using optical communication may be used as the wireless network. In this case, the control unit 2 and the machining unit 1 may be configured to be able to send and receive various information via the network. The control unit 2 may also be able to send information such as commands and control parameters to the machining unit 1 via the network. The machining unit 1 may include a receiving device that receives information such as commands and control parameters from the control unit 2 via the network. The machining unit 1 may also include a transmitting device that transmits information such as commands and control parameters to the control unit 2 via the network (i.e., an output device that outputs information to the control unit 2). Alternatively, a first control device that performs part of the processing performed by the control unit 2 may be provided inside the machining unit 1, while a second control device that performs another part of the processing performed by the control unit 2 may be provided outside the machining unit 1.

[0046] A computational model that can be constructed by machine learning may be implemented in the control unit 2 by the computation device executing a computer program. An example of a computational model that can be constructed by machine learning is a computational model including a neural network (so-called artificial intelligence (AI)). In this case, learning of the computational model may include learning of parameters of the neural network (e.g., at least one of weights and biases). The control unit 2 may control the operation of the machining unit 1 using the computational model. That is, the operation of controlling the operation of the machining unit 1 may include the operation of controlling the operation of the machining unit 1 using the computational model. Note that a computational model that has been constructed by offline machine learning using training data may be implemented in the control unit 2. Furthermore, the computational model implemented in the control unit 2 may be updated by online machine learning on the control unit 2. Alternatively, the control unit 2 may control the operation of the machining unit 1 using a computational model implemented in a device external to the control unit 2 (i.e., a device provided outside the machining unit 1) in addition to or instead of the computational model implemented in the control unit 2.

[0047] The recording medium for recording the computer program executed by the control unit 2 may be at least one of a CD-ROM, CD-R, CD-RW, flexible disk, optical disk such as MO, DVD-ROM, DVD-RAM, DVD-R, DVD+R, DVD-RW, DVD+RW, and Blu-ray®, magnetic medium such as magnetic tape, magneto-optical disk, semiconductor memory such as USB memory, and any other medium capable of storing a program. The recording medium may also include a device capable of recording a computer program (e.g., a general-purpose device or a dedicated device in which a computer program is implemented in an executable state in at least one of software and firmware). Furthermore, each process or function included in the computer program may be realized by logical processing blocks realized within the control unit 2 when the control unit 2 (i.e., a computer) executes the computer program, or by hardware such as a predetermined gate array (FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit)) included in the control unit 2, or may be realized in a form in which logical processing blocks and partial hardware modules that realize some of the hardware elements are mixed.

[0048] (1-2) Configuration of the processing head 13 Next, an example of the configuration of the processing head 13 will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing an example of the configuration of the processing head 13.

[0049] 3, the processing light EL generated by the processing light source 11 is incident on the processing head 13 via an optical transmission member 111 such as an optical fiber. The processing light source 11 may be disposed outside the processing head 13. The processing light source 11 may also be disposed inside the processing head 13.

[0050] As described above, the processing head 13 includes the processing optical system 131, the measurement optical system 132, the composite optical system 133, and the objective optical system 134. The processing optical system 131, the measurement optical system 132, the composite optical system 133, and the objective optical system 134 may be housed in a head housing 135 of the processing head 13. The processing optical system 131, the measurement optical system 132, the composite optical system 133, and the objective optical system 134 may be attached to the head housing 135. However, at least one of the processing optical system 131, the measurement optical system 132, the composite optical system 133, and the objective optical system 134 does not have to be housed in the head housing 135.

[0051] The processing optical system 131 is an optical system into which the processing light EL from the processing light source 11 is incident. The processing optical system 131 is an optical system that emits the processing light EL that has entered the processing optical system 131 toward the combining optical system 133. The processing light EL emitted from the processing optical system 131 is irradiated onto the workpiece W via the combining optical system 133 and the objective optical system 134. In this way, the processing optical system 131 processes the workpiece W by irradiating the processing light EL onto the workpiece W via the objective optical system 134. For this reason, the processing optical system 131 may also be referred to as a processing device.

[0052] The processing optical system 131 may include, for example, a position adjustment optical system 1311, an angle adjustment optical system 1312, and a focusing position adjustment optical system 1313. The position adjustment optical system 1311 can adjust the emission position of the processing light EL from the processing optical system 131. The position adjustment optical system 1311 may include, for example, a parallel plane plate that can be tilted with respect to the traveling direction of the processing light EL, and the emission position of the processing light EL may be changed by changing the tilt angle of the parallel plane plate. The angle adjustment optical system 1312 can adjust the emission angle (i.e., emission direction) of the processing light EL from the processing optical system 131. The angle adjustment optical system 1312 may include, for example, a mirror that can be tilted with respect to the traveling direction of the processing light EL, and the emission angle of the processing light EL may be changed by changing the tilt angle of this mirror. The focusing position adjustment optical system 1313 is an optical element that can adjust the focusing position of the processing light EL in the traveling direction of the processing light EL. The focusing position adjustment optical system 1313 may include, for example, a plurality of lenses arranged along the traveling direction of the processing light EL. In this case, the focusing position of the processing light EL is adjusted by moving at least one of the plurality of lenses along its optical axis direction. Alternatively, the focusing position adjustment optical system 1313 may include, for example, an optical member (typically, a galvanometer mirror) that can move the focusing position of the processing light EL along a desired direction by deflecting the processing light EL. However, the processing optical system 131 does not have to include at least one of the position adjustment optical system 1311, the angle adjustment optical system 1312, and the focusing position adjustment optical system 1313.

[0053] The processing light EL emitted from the processing optical system 131 enters the combining optical system 133. The combining optical system 133 includes a beam splitter (e.g., a polarizing beam splitter) 1331. The beam splitter 1331 emits the processing light EL incident on the beam splitter 1331 toward the objective optical system 134. In the example shown in FIG. 3, the processing light EL incident on the beam splitter 1331 passes through the polarization separation surface of the beam splitter 1331 and is emitted toward the objective optical system 134. Therefore, in the example shown in FIG. 3, the processing light EL enters the polarization separation surface of the beam splitter 1331 in a state having a polarization direction that can pass through the polarization separation surface (e.g., a polarization direction that becomes p-polarized light with respect to the polarization separation surface).

[0054] The processing light EL emitted from the combining optical system 133 is incident on the objective optical system 134. The objective optical system 134 emits the processing light EL that has entered the objective optical system 134 toward the workpiece W. The objective optical system 134 includes a galvanometer mirror 1341 and an fθ lens 1342.

[0055] The processing light EL incident on the objective optical system 134 is incident on the galvanometer mirror 1341. The galvanometer mirror 1341 deflects the processing light EL (i.e., changes the emission angle of the processing light EL). By deflecting the processing light EL, the galvanometer mirror 1341 changes the focusing position of the processing light EL in a plane intersecting the optical axis EX of the fθ lens 1342 (i.e., in a plane along the XY plane). Typically, as shown in FIG. 3, the processing head 13 irradiates the workpiece W with the processing light EL in a state where the optical axis EX of the fθ lens 1342 intersects with the surface of the workpiece W. Therefore, when the focusing position of the processing light EL in the plane intersecting the optical axis EX is changed, the target irradiation position PA of the processing light EL on the surface of the workpiece W is changed in a direction along the surface of the workpiece W. In other words, the target irradiation position PA of the processing light EL is changed along at least one of the X-axis direction and the Y-axis direction.

[0056] The galvanometer mirror 1341 includes an X-scan mirror 1341X and a Y-scan mirror 1341Y. Each of the X-scan mirror 1341X and the Y-scan mirror 1341Y is a variable tilt angle mirror whose angle with respect to the optical path of the processing light EL incident on the galvanometer mirror 1341 is changeable. The X-scan mirror 1341X deflects the processing light EL so as to change the irradiation position of the processing light EL on the workpiece W along the X-axis direction. In this case, the X-scan mirror 1341X may be rotatable or swingable about the Y-axis. The Y-scan mirror 1341Y deflects the processing light EL so as to change the irradiation position of the processing light EL on the workpiece W along the Y-axis direction. In this case, the Y-scan mirror 1341Y may be rotatable or swingable about the X-axis.

[0057] The galvanometer mirror 1341 allows the processing light EL to scan a processing shot area PSA defined with reference to the processing head 13. In other words, the galvanometer mirror 1341 allows the target irradiation position PA to move within the processing shot area PSA defined with reference to the processing head 13. An example of the processing shot area PSA is shown in FIG. 4. As shown in FIG. 4, the processing shot area PSA indicates an area (in other words, a range) where processing is performed by the processing head 13 while the positional relationship between the processing head 13 and the workpiece W is fixed (i.e., without change). Typically, the processing shot area PSA is set to coincide with or be narrower than the scanning range of the processing light EL deflected by the galvanometer mirror 1341 while the positional relationship between the processing head 13 and the workpiece W is fixed. Furthermore, the processing shot area PSA (target irradiation position PA) can be relatively moved on the surface of the workpiece W by moving the processing head 13 with the head drive system 14 and / or moving the stage 16 with the stage drive system 17.

[0058] The processing shot area PSA may be the maximum range of the range in which processing is performed by the processing head 13 with the positional relationship between the processing head 13 and the workpiece W fixed. The scanning range of the processing light EL deflected by the galvanometer mirror 1341 may be the scanning range of the processing light EL when the deflection angle is the maximum within the range of deflection angles determined by the galvanometer mirror 1341. In the example shown in FIG. 4, the shape of the processing shot area PSA is rectangular. However, the shape of the processing shot area PSA is not limited to the rectangular shape shown in FIG. 4. For example, the shape of the processing shot area PSA may be polygonal, circular, or elliptical. The shape of the processing shot area PSA may be set by an operator of the processing system SYS. The size of the processing shot area PSA may be set by an operator of the processing system SYS.

[0059] The objective optical system 134 may include any deflection optical element capable of deflecting the processing light EL in addition to or instead of the galvanometer mirror 1341. An example of such a deflection optical element is a polygon mirror having multiple reflecting surfaces with different angles. The polygon mirror is rotatable so as to change the angle of incidence of the processing light EL with respect to one reflecting surface while the processing light EL is irradiated onto the one reflecting surface and to switch the reflecting surface onto which the processing light EL is irradiated among multiple reflecting surfaces. Other examples of such a deflection optical element include at least one of an acousto-optic element, an electro-optic element, an MEMS mirror, and a two-dimensional mirror that can rotate (oscillate) in two axial directions.

[0060] 3, the processing light EL from the galvanometer mirror 1341 is incident on the fθ lens 1342. The fθ lens 1342 irradiates the processing light EL from the galvanometer mirror 1341 onto the workpiece W. Specifically, the fθ lens 1342 emits the processing light EL in a direction along the optical axis EX of the fθ lens 1342. As a result, the processing light EL emitted by the fθ lens 1342 travels in a direction along the optical axis EX and is incident on the workpiece W.

[0061] The fθ lens 1342 focuses the processing light EL from the galvanometer mirror 1341 onto the workpiece W. In this case, the processing light EL emitted from the fθ lens 1342 may be irradiated onto the workpiece W without passing through another optical element having power (in other words, an optical member such as a lens). In this case, the fθ lens 1342 may be referred to as the final optical element because it is the optical element having the final stage of power (in other words, the optical element closest to the workpiece W) among multiple optical elements arranged on the optical path of the processing light EL.

[0062] In order for the machining head 13 to irradiate the workpiece W with the machining light EL, the machining head 13 only needs to be equipped with at least an fθ lens 1342. In this case, the machining light EL may be incident on the machining head 13 via the machining optical system 131, the synthesis optical system 133, and the galvanometer mirror 1341, which are arranged outside the machining head 13. The machining head 13 may irradiate the machining light EL incident on the machining head 13 onto the workpiece W via the fθ lens 1342.

[0063] Furthermore, measurement light ML generated by the measurement light source 12 is incident on the processing head 13 via an optical transmission member 121 such as an optical fiber. The measurement light source 12 may be arranged outside the processing head 13. The measurement light source 12 may also be arranged inside the processing head 13.

[0064] The measurement light source 12 may include an optical frequency comb light source. An optical frequency comb light source is a light source that can generate light containing frequency components equally spaced on the frequency axis (hereinafter referred to as an "optical frequency comb") as pulsed light. In this case, the measurement light source 12 emits pulsed light containing frequency components equally spaced on the frequency axis as measurement light ML. However, the measurement light source 12 may include a light source other than the optical frequency comb light source.

[0065] In the example shown in FIG. 3, the processing system SYS includes a plurality of measurement light sources 12. For example, the processing system SYS may include a measurement light source 12#1 and a measurement light source 12#2. The plurality of measurement light sources 12 may each emit a plurality of measurement light beams ML that are phase-synchronized and coherent with each other. For example, the plurality of measurement light sources 12 may have different oscillation frequencies. Therefore, the plurality of measurement light beams ML emitted by the plurality of measurement light sources 12 may be measurement light beams ML with different pulse frequencies (for example, the number of pulsed light beams per unit time, which is the reciprocal of the emission period of the pulsed light). However, the processing system SYS may also include a single measurement light source 12.

[0066] The measurement light ML emitted from the measurement light source 12 is incident on the measurement optical system 132. The measurement optical system 132 is an optical system that emits the measurement light ML that has entered the measurement optical system 132 toward the combining optical system 133. The measurement light ML emitted from the measurement optical system 132 is irradiated onto the measurement object M via the combining optical system 133 and the objective optical system 134. That is, in order to measure the measurement object M, the measurement optical system 132 irradiates the measurement light ML onto the measurement object M via the combining optical system 133 and the objective optical system 134.

[0067] The measurement optical system 132 includes, for example, a mirror 1320, a beam splitter 1321, a beam splitter 1322, a detector 1323, a beam splitter 1324, a mirror 1325, a detector 1326, a mirror 1327, and a galvanometer mirror 1328. However, the measurement optical system 132 does not necessarily include the galvanometer mirror 1328.

[0068] The measurement light ML emitted from the measurement light source 12 is incident on the beam splitter 1321. Specifically, the measurement light ML emitted from the measurement light source 12#1 (hereinafter referred to as "measurement light ML#1") is incident on the beam splitter 1321. The measurement light ML emitted from the measurement light source 12#2 (hereinafter referred to as "measurement light ML#2") is incident on the beam splitter 1321 via the mirror 1320. The beam splitter 1321 outputs the measurement light ML#1 and ML#2 incident on the beam splitter 1321 toward the beam splitter 1322. In other words, the beam splitter 1321 outputs the measurement light ML#1 and ML#2 incident on the beam splitter 1321 from different directions in the same direction (i.e., the direction in which the beam splitter 1322 is disposed).

[0069] The beam splitter 1322 reflects measurement light ML#1-1, which is a part of measurement light ML#1 that is incident on the beam splitter 1322, toward the detector 1323. The beam splitter 1322 emits measurement light ML#1-2, which is another part of measurement light ML#1 that is incident on the beam splitter 1322, toward the beam splitter 1324. The beam splitter 1322 reflects measurement light ML#2-1, which is a part of measurement light ML#2 that is incident on the beam splitter 1322, toward the detector 1323. The beam splitter 1322 emits measurement light ML#2-2, which is another part of measurement light ML#2 that is incident on the beam splitter 1322, toward the beam splitter 1324.

[0070] The measurement beams ML#1-1 and ML#2-1 emitted from the beam splitter 1322 are incident on the detector 1323. The detector 1323 receives (i.e., detects) the measurement beams ML#1-1 and ML#2-1. In particular, the detector 1323 receives interference light generated by the interference between the measurement beams ML#1-1 and ML#2-1. Note that the operation of receiving interference light generated by the interference between the measurement beams ML#1-1 and ML#2-1 may be considered equivalent to the operation of receiving the measurement beams ML#1-1 and ML#2-1. The detection result of the detector 1323 is output to the control unit 2.

[0071] The measurement beams ML#1-2 and ML#2-2 emitted from the beam splitter 1322 are incident on the beam splitter 1324. The beam splitter 1324 emits at least a portion of the measurement beam ML#1-2 incident on the beam splitter 1324 toward a mirror 1325. The beam splitter 1324 emits at least a portion of the measurement beam ML#2-2 incident on the beam splitter 1324 toward a mirror 1327.

[0072] The measurement light ML#1-2 emitted from the beam splitter 1324 is incident on the mirror 1325. The measurement light ML#1-2 incident on the mirror 1325 is reflected by the reflecting surface of the mirror 1325 (the reflecting surface may also be referred to as a reference surface). Specifically, the mirror 1325 reflects the measurement light ML#1-2 incident on the mirror 1325 toward the beam splitter 1324. That is, the mirror 1325 emits the measurement light ML#1-2 incident on the mirror 1325 as measurement light ML#1-3, which is its reflected light, toward the beam splitter 1324. In this case, the measurement light ML#1-3 may also be referred to as a reference light. The measurement light ML#1-3 emitted from the mirror 1325 is incident on the beam splitter 1324. The beam splitter 1324 emits the measurement beams ML#1-3 incident on the beam splitter 1324 toward the beam splitter 1322. The measurement beams ML#1-3 emitted from the beam splitter 1324 are incident on the beam splitter 1322. The beam splitter 1322 emits the measurement beams ML#1-3 incident on the beam splitter 1322 toward the detector 1326.

[0073] On the other hand, measurement light ML#2-2 emitted from beam splitter 1324 is incident on mirror 1327. Mirror 1327 reflects measurement light ML#2-2 incident on mirror 1327 toward galvanometer mirror 1328. That is, mirror 1327 emits measurement light ML#2-2 incident on mirror 1327 toward galvanometer mirror 1328.

[0074] The galvanometer mirror 1328 deflects the measurement light ML#2-2 (i.e., changes the emission angle of the measurement light ML#2-2). By deflecting the measurement light ML#2-2, the galvanometer mirror 1328 changes the focusing position of the measurement light ML#2-2 in a plane intersecting the optical axis EX of the fθ lens 1342 (i.e., in a plane along the XY plane). Typically, as shown in FIG. 3, the machining head 13 irradiates the workpiece W with the measurement light ML#2-2 in a state in which the optical axis EX of the fθ lens 1342 intersects with the surface of the measurement object M (in the example shown in FIG. 3), the workpiece W). Therefore, when the focusing position of the measurement light ML#2-2 in the plane intersecting the optical axis EX is changed, the target irradiation position MA of the measurement light ML#2-2 on the surface of the measurement object M is changed in a direction along the surface of the measurement object M. In other words, the target irradiation position MA of the measurement light ML#2-2 is changed along at least one of the X-axis direction and the Y-axis direction.

[0075] The galvanometer mirror 1328 includes an X-scan mirror 1328X and a Y-scan mirror 1328Y. Each of the X-scan mirror 1328X and the Y-scan mirror 1328Y is a variable tilt angle mirror whose angle with respect to the optical path of the measurement light ML#2-2 incident on the galvanometer mirror 1328 is changeable. The X-scan mirror 1328X deflects the measurement light ML#2-2 so as to change the irradiation position of the measurement light ML#2-2 on the measurement object M along the X-axis direction. In this case, the X-scan mirror 1328X may be rotatable or swingable about the Y-axis. The Y-scan mirror 1328Y deflects the processing light EL so as to change the irradiation position of the measurement light ML#2-2 on the measurement object M along the Y-axis direction. In this case, the Y-scan mirror 1328Y may be rotatable or swingable about the X-axis.

[0076] The measurement light ML#2-2 from the galvanometer mirror 1328 enters the combining optical system 133. The beam splitter 1331 of the combining optical system 133 emits the measurement light ML#2-2 that entered the beam splitter 1331 toward the objective optical system 134. In the example shown in FIG. 3, the measurement light ML#2-2 that entered the combining optical system 133 is reflected at the polarization separation surface and then emitted toward the objective optical system 134. Therefore, in the example shown in FIG. 3, the measurement light ML#2-2 enters the polarization separation surface of the beam splitter 1331 while having a polarization direction that can be reflected at the polarization separation surface (for example, a polarization direction that becomes s-polarized light with respect to the polarization separation surface).

[0077] As described above, the processing light EL is incident on the beam splitter 1331 in addition to the measurement light ML#2-2. That is, both the measurement light ML#2-2 and the processing light EL pass through the beam splitter 1331. The beam splitter 1331 outputs the processing light EL and the measurement light ML#2-2, which have entered the beam splitter 1331 from different directions, in the same direction (that is, toward the same objective optical system 134). Therefore, the beam splitter 1331 essentially functions as a combining optical element that combines the processing light EL and the measurement light ML#2-2.

[0078] Note that, when the wavelengths of the processing light EL and the measurement light ML are different, the combining optical system 133 may include a dichroic mirror as a combining optical element instead of the beam splitter 1331. Even in this case, the combining optical system 133 can combine the processing light EL and the measurement light ML#2-2 using the dichroic mirror (that is, combine the optical path of the processing light EL and the optical path of the measurement light ML#2-2).

[0079] The measurement light ML#2-2 emitted from the beam splitter 1331 is incident on the galvanometer mirror 1341. The galvanometer mirror 1341 deflects the measurement light ML#2-2 in the same way as when it deflects the processing light EL. Therefore, the galvanometer mirror 1341 can change the target irradiation position MA of the measurement light ML#2-2 on the surface of the measurement object M in a direction along the surface of the measurement object M.

[0080] As described above, the processing light EL is incident on the galvanometer mirror 1341 in addition to the measurement light ML#2-2. That is, the processing light EL and measurement light ML#2-2 combined by the beam splitter 1331 are incident on the galvanometer mirror 1341. Therefore, both the measurement light ML#2-2 and the processing light EL pass through the same galvanometer mirror 1341. For this reason, the galvanometer mirror 1341 can synchronously change the target irradiation position PA of the processing light EL and the target irradiation position MA of the measurement light ML#2-2. That is, the galvanometer mirror 1341 can change the target irradiation position PA of the processing light EL and the target irradiation position MA of the measurement light ML#2-2 in conjunction with each other.

[0081] On the other hand, as described above, the measurement light ML#2-2 is irradiated onto the measurement object M via the galvanometer mirror 1328, while the processing light EL is irradiated onto the workpiece W without passing through the galvanometer mirror 1328. Therefore, the processing system SYS can use the galvanometer mirror 1328 to independently move the target irradiation position MA of the measurement light ML#2-2 relative to the target irradiation position PA of the processing light EL. The processing system SYS can independently change the target irradiation position PA of the processing light EL and the target irradiation position MA of the measurement light ML#2-2. The processing system SYS can change the positional relationship between the target irradiation position PA of the processing light EL and the target irradiation position MA of the measurement light ML#2-2. Note that if the positional relationship between the target irradiation position PA of the processing light EL and the target irradiation position MA of the measurement light ML#2-2 is not changed, the processing system SYS does not need to include the galvanometer mirror 1328.

[0082] At least one of the galvanometer mirrors 1341 and 1328 enables the measurement light ML to scan a measurement shot area MSA that is determined based on the processing head 13. In other words, at least one of the galvanometer mirrors 1341 and 1328 enables the target irradiation position MA to move within the measurement shot area MSA that is determined based on the processing head 13. An example of the measurement shot area MSA is shown in FIG. 5. As shown in FIG. 5, the measurement shot area MSA indicates an area (in other words, a range) where measurement is performed by the processing head 13 while the positional relationship between the processing head 13 and the measurement object M is fixed (i.e., without change). Typically, the measurement shot area MSA is set to coincide with or be narrower than the scanning range of the measurement light ML deflected by at least one of the galvanometer mirrors 1341 and 1328 while the positional relationship between the processing head 13 and the measurement object M is fixed. Furthermore, by moving the processing head 13 using the above-mentioned head drive system 14 and / or by moving the stage 16 using the stage drive system 17, the measurement shot area MSA (target irradiation position MA) can be moved relatively on the surface of the measurement object M.

[0083] The measurement shot area MSA may be the maximum range of the range in which measurement is performed by the processing head 13 with the positional relationship between the processing head 13 and the measurement target M fixed. The scanning range of the measurement light ML deflected by the galvanometer mirror 1341 may be the scanning range of the measurement light ML when the deflection angle is the maximum within the range of deflection angles determined by the galvanometer mirror 1341. In the example shown in FIG. 5, the shape of the measurement shot area MSA is rectangular. However, the shape of the measurement shot area MSA is not limited to the rectangular shape shown in FIG. 5. For example, the shape of the measurement shot area MSA may be polygonal, circular, or elliptical. The shape of the measurement shot area MSA may be set by an operator of the processing system SYS. The size of the measurement shot area MSA may be set by an operator of the processing system SYS.

[0084] 3, measurement light ML#2-2 emitted from the galvanometer mirror 1341 is incident on the fθ lens 1342. The fθ lens 1342 irradiates the measurement light ML#2-2 from the galvanometer mirror 1341 onto the measurement object M. Specifically, the fθ lens 1342 emits measurement light ML#2-2 in a direction along the optical axis EX of the fθ lens 1342. As a result, measurement light ML#2-2 emitted from the fθ lens 1342 travels in a direction along the optical axis EX and is incident on the measurement object M.

[0085] The fθ lens 1342 may focus the measurement light ML#2-2 from the galvanometer mirror 1341 onto the measurement object M. In this case, the measurement light ML#2-2 emitted from the fθ lens 1342 may be irradiated onto the measurement object M without passing through another optical element having power (in other words, an optical member such as a lens).

[0086] When the measurement light ML#2-2 is irradiated onto the measurement object M, light resulting from the irradiation of the measurement light ML#2-2 is generated from the measurement object M. In other words, when the measurement object M is irradiated with the measurement light ML#2-2, light resulting from the irradiation of the measurement light ML#2-2 is emitted from the measurement object M. The light resulting from the irradiation of the measurement light ML#2-2 (in other words, light emitted from the measurement object M due to the irradiation of the measurement light ML#2-2) may include at least one of the measurement light ML#2-2 reflected by the measurement object M (i.e., reflected light), the measurement light ML#2-2 scattered by the measurement object M (i.e., scattered light), the measurement light ML#2-2 diffracted by the measurement object M (i.e., diffracted light), and the measurement light ML#2-2 transmitted through the measurement object M (i.e., transmitted light).

[0087] At least a part of the light emitted from the measurement object M due to the irradiation of the measurement light ML#2-2 is incident on the objective optical system 134 as returned light RL. Specifically, of the light emitted from the measurement object M due to the irradiation of the measurement light ML#2-2, light that travels along the optical path of the measurement light ML#2-2 incident on the measurement object M is incident on the objective optical system 134 as returned light RL. In this case, the optical path of the measurement light ML#2-2 that is emitted from the fθ lens 1342 and incident on the measurement object may be the same as the optical path of the returned light RL that is emitted from the measurement object M and incident on the fθ lens 1342. As an example, when the measurement light ML is perpendicularly incident on the measurement object M, the returned light RL may be light that is mainly composed of specularly reflected light of the measurement light ML. Of course, when the measurement light ML is perpendicularly incident on the measurement object M, the return light RL may include light other than the specularly reflected light of the measurement light ML (for example, at least one of the diffusely reflected light, scattered light, transmitted light, and diffracted light of the measurement light ML). As another example, when the measurement light ML is obliquely incident on the measurement object M (in other words, non-perpendicularly incident), the return light RL may be light mainly composed of the diffusely reflected light of the measurement light ML. Of course, when the measurement light ML is obliquely incident on the measurement object M, the return light RL may include light other than the diffusely reflected light of the measurement light ML (for example, at least one of the specularly reflected light, scattered light, transmitted light, and diffracted light of the measurement light ML). The return light RL incident on the objective optical system 134 enters the combining optical system 133 via the fθ lens 1342 and the galvanometer mirror 1341. The beam splitter 1331 of the combining optical system 133 emits the return light RL incident on the beam splitter 1331 toward the measurement optical system 132. 3, the return light RL incident on the beam splitter 1331 is reflected by the polarization separation surface and emitted toward the measurement optical system 132. Therefore, in the example shown in Fig. 3, the return light RL is incident on the polarization separation surface of the beam splitter 1331 in a state in which it has a polarization direction that allows it to be reflected by the polarization separation surface.

[0088] The return light RL emitted from the beam splitter 1331 is incident on a galvanometer mirror 1328 of the measurement optical system 132. The galvanometer mirror 1328 emits the return light RL incident on the galvanometer mirror 1328 toward a mirror 1327. The mirror 1327 reflects the return light RL incident on the mirror 1327 toward the beam splitter 1324. The beam splitter 1324 emits at least a portion of the return light RL incident on the beam splitter 1324 toward the beam splitter 1322. The beam splitter 1322 emits at least a portion of the return light RL incident on the beam splitter 1322 toward a detector 1326.

[0089] As described above, in addition to the return light RL, the measurement light ML#1-3 is incident on the detector 1326. That is, the return light RL that travels toward the detector 1326 via the measurement object M and the measurement light ML#1-3 that travels toward the detector 1326 without traveling through the measurement object M are incident on the detector 1326. The detector 1326 receives (i.e., detects) the measurement light ML#1-3 and the return light RL. In particular, the detector 1326 receives interference light generated by interference between the measurement light ML#1-3 and the return light RL. Note that the operation of receiving interference light generated by interference between the measurement light ML#1-3 and the return light RL may be considered equivalent to the operation of receiving the measurement light ML#1-3 and the return light RL. The detection result of the detector 1326 is output to the control unit 2.

[0090] In this way, the measurement optical system 132 irradiates the measurement object M with measurement light ML via the objective optical system 134, and receives return light RL from the measurement object M via the objective optical system 134. Such a measurement optical system 132 may also be referred to as a light detection device.

[0091] The control unit 2 acquires the detection results of the detector 1323 and the detector 1326. The control unit 2 may generate measurement data of the measurement object M (e.g., measurement data related to at least one of the position and the shape of the measurement object M) based on the detection results of the detector 1323 and the detection results of the detector 1326.

[0092] Specifically, since the pulse frequency of measurement light ML#1 is different from the pulse frequency of measurement light ML#2, the pulse frequency of measurement light ML#1-1 is different from the pulse frequency of measurement light ML#2-1. Therefore, the interference light between measurement light ML#1-1 and measurement light ML#2-1 is interference light in which pulse light appears in synchronization with the timing when the pulse light constituting measurement light ML#1-1 and the pulse light constituting measurement light ML2#2-1 simultaneously enter the detector 1323. Similarly, the pulse frequency of measurement light ML#1-3 is different from the pulse frequency of return light RL. Therefore, the interference light between measurement light ML#1-3 and return light RL is interference light in which pulse light appears in synchronization with the timing when the pulse light constituting measurement light ML#1-3 and the pulse light constituting return light RL simultaneously enter the detector 1326. Here, the position (position on the time axis) of the pulse light of the interference light detected by the detector 1326 varies depending on the positional relationship between the processing head 13 and the measurement object M. This is because the interference light detected by the detector 1326 is interference light between the return light RL traveling toward the detector 1326 via the measurement object M and the measurement light ML#1-3 traveling toward the detector 1326 without traveling through the measurement object M. On the other hand, the position (position on the time axis) of the pulsed light of interference light detected by the detector 1323 does not vary depending on the positional relationship between the processing head 13 and the measurement object M (that is, essentially, the positional relationship between the processing head 13 and the measurement object M). For this reason, it can be said that the time difference between the pulsed light of interference light detected by the detector 1326 and the pulsed light of interference light detected by the detector 1323 indirectly indicates the positional relationship between the processing head 13 and the measurement object M. Specifically, it can be said that the time difference between the pulsed light of interference light detected by the detector 1326 and the pulsed light of interference light detected by the detector 1323 indirectly indicates the distance between the processing head 13 and the measurement object M in the direction along the optical path of the measurement light ML (that is, the direction along the traveling direction of the measurement light ML). Therefore, the control unit 2 can calculate the distance between the processing head 13 and the object to be measured M in a direction along the optical path of the measurement light ML (e.g., the Z-axis direction) based on the time difference between the pulsed light of interference light detected by detector 1326 and the pulsed light of interference light detected by detector 1323.In other words, the control unit 2 can calculate the position of the measurement object M in a direction along the optical path of the measurement light ML (e.g., the Z-axis direction). More specifically, the control unit 2 can calculate the distance between the irradiated portion of the measurement object M irradiated with the measurement light ML#2-2 and the processing head 13. The control unit 2 can calculate the position of the irradiated portion in a direction along the optical path of the measurement light ML (e.g., the Z-axis direction). Furthermore, because the irradiation position of the measurement light ML#2-2 on the measurement object M is determined by the drive states of the galvanometer mirrors 1341 and 1328, the control unit 2 can calculate the position of the irradiated portion in a direction intersecting the optical path of the measurement light ML (e.g., at least one of the X-axis direction and the Y-axis direction) based on the drive states of the galvanometer mirrors 1341 and 1328. As a result, the control unit 2 can generate measurement data indicating the position of the irradiated portion in a measurement coordinate system based on the processing head 13 (e.g., a position in a three-dimensional coordinate space). Furthermore, information regarding the position of the processing head 13 and information regarding the position of the stage 16 can be acquired from the position measurement devices 15 and 18, respectively. Therefore, the control unit 2 can generate measurement data indicating the position of the irradiated portion in a reference coordinate system that serves as the basis for the processing system SYS (for example, a three-dimensional position in a three-dimensional coordinate space) based on the position of the irradiated portion in the measurement coordinate system, information regarding the position of the processing head 13, and information regarding the position of the stage 16.

[0093] The processing head 13 may irradiate multiple portions of the measurement object M with the measurement light ML#2-2. For example, at least one of the galvanometer mirrors 1341 and 1328 may change the irradiation position of the measurement light ML#2-2 on the measurement object M so that the processing head 13 irradiates multiple portions of the measurement object M with the measurement light ML#2-2. For example, at least one of the processing head 13 and the stage 16 may move so that the processing head 13 irradiates multiple portions of the measurement object M with the measurement light ML#2-2. When the measurement light ML#2-2 is irradiated onto multiple portions of the measurement object M, the control unit 2 can generate measurement data indicating the positions of the multiple portions of the measurement object M. As a result, the control unit 2 can generate measurement data indicating the shape of the measurement object M based on the measurement data indicating the positions of the multiple portions. For example, the control unit 2 can generate measurement data indicating the shape of the measurement object M by calculating a three-dimensional shape composed of virtual planes (or curved surfaces) connecting the multiple portions whose positions have been identified as the shape of the measurement object M.

[0094] (2) Operations performed by the processing system SYS Next, the operations performed by the processing system SYS will be described. In particular, the operations performed by the processing system SYS using the measurement light ML will be described. As described above, the processing system SYS may perform a movement error calculation operation to calculate a movement error of at least one of the processing head 13 and the stage 16 using the measurement results of the reference member FM using the measurement light ML. Furthermore, before performing the movement error calculation operation, the processing system SYS may perform an optical calibration operation to align the target irradiation position PA where the processing head 13 irradiates the processing light EL with the target irradiation position MA where the processing head 13 irradiates the measurement light ML. Furthermore, the processing system SYS may perform a deformation error calculation operation to calculate a movement error that occurs in the movement of at least one of the processing head 13 and the stage 16 due to deformation of a member included in the processing unit 1. Therefore, in the following explanation, the optical calibration operation, the movement error calculation operation, and the deformation error calculation operation will be described in order.

[0095] (2-1) Optical calibration operation First, the optical calibration operation will be described. As described above, the optical calibration operation is an operation for aligning the target irradiation position PA onto which the machining head 13 irradiates the processing light EL with the target irradiation position MA onto which the machining head 13 irradiates the measurement light ML. As described above, the target irradiation position PA moves within a processing shot area PSA set on the workpiece W by the galvanometer mirror 1341. Similarly, the target irradiation position MA moves within a measurement shot area MSA set on the measurement target M by the galvanometer mirror 1341. Typically, in a direction intersecting the optical axis EX of the fθ lens 1342 (e.g., at least one of the X-axis direction and the Y-axis direction), the target irradiation position PA onto which the processing light EL from the galvanometer mirror 1341 in one state is irradiated coincides with the target irradiation position MA onto which the measurement light ML from the galvanometer mirror 1341 in the same state is irradiated. Note that the state of the galvanometer mirror 1341 may include the angles of the X-scanning mirror 1341X and the Y-scanning mirror 1341Y. However, due to some factor, the target irradiation position PA onto which the processing light EL from the galvanometer mirror 1341 in one state is irradiated may not coincide with the target irradiation position MA onto which the measurement light ML from the galvanometer mirror 1341 in the same state is irradiated. The optical calibration operation may be an operation that calculates the relationship (e.g., positional relationship) between such target irradiation positions PA and MA. In the following description, an example will be described in which the optical calibration operation is an operation that calculates the amount of positional deviation between such target irradiation positions PA and MA. That is, in the following description, an example will be described in which the amount of positional deviation between the target irradiation position PA and MA is used as the relationship between the target irradiation position PA and MA.

[0096] In this embodiment, the machining system SYS may perform an optical calibration operation in which a test workpiece Wt (or a workpiece W that is actually being machined) is irradiated with the machining light EL, and machining marks formed on the workpiece Wt are measured using the measurement light ML, thereby calculating the relationship between the target irradiation position PA of the machining light EL and the target irradiation position MA of the measurement light ML. An example of an optical calibration operation in which machining marks are measured using such measurement light ML will be described below.

[0097] Specifically, when there is no positional deviation between the target irradiation position PA and the target irradiation position MA (i.e., the amount of positional deviation is zero), the target irradiation position PA coincides with the target irradiation position MA. Therefore, as shown in FIG. 6( a), when a machining mark is formed on the workpiece Wt by the machining light EL from the galvanometer mirror 1341 in the first state, the measurement light ML from the galvanometer mirror 1341 in the same first state is irradiated onto the machining mark. On the other hand, when there is a positional deviation between the target irradiation position PA and the target irradiation position MA (i.e., the amount of positional deviation is not zero), the target irradiation position PA does not coincide with the target irradiation position MA. Therefore, as shown in FIG. 6( b), when a machining mark is formed on the workpiece Wt by the machining light EL from the galvanometer mirror 1341 in the first state, the measurement light ML from the galvanometer mirror 1341 in the same first state is not irradiated onto the machining mark. In this case, if at least one of the machining head 13 and the stage 16 is moved a predetermined amount, the measurement light ML will be irradiated onto the machining mark. In this case, the amount of movement of at least one of the processing head 13 and the stage 16 corresponds to the amount of positional deviation between the target irradiation position PA and the target irradiation position MA.

[0098] For this reason, the control unit 2 may calculate the amount of positional deviation between the target irradiation position PA and the target irradiation position MA by controlling the machining unit 1 to perform the following operation. First, the control unit 2 may set the state of the galvanometer mirror 1341 to a predetermined state, and then control the machining head 13 to irradiate the workpiece Wt with the machining light EL to form a machining mark on the workpiece Wt. Then, the control unit 2 may control the machining head 13 to irradiate the workpiece Wt with the measurement light ML while maintaining the state of the galvanometer mirror 1341 in the predetermined state. In this case, the control unit 2 may determine whether or not a machining mark can be detected from the measurement results of the workpiece Wt using the measurement light ML. If it is determined that a machining mark can be detected from the measurement results of the workpiece Wt using the measurement light ML, it is estimated that the measurement light ML is irradiating the machining mark. For this reason, in this case, the control unit 2 may determine that the amount of positional deviation between the target irradiation position PA and the target irradiation position MA is zero. On the other hand, if it is determined that the machining traces cannot be detected from the measurement results of the workpiece Wt using the measurement light ML, it is estimated that the measurement light ML is not irradiated onto the machining traces. Therefore, in this case, the control unit 2 may move at least one of the machining head 13 and the stage 16 until the machining traces can be detected from the measurement results of the workpiece Wt using the measurement light ML (i.e., until the measurement light ML is irradiated onto the machining traces). In this case, the control unit 2 may calculate, from the measurement results of at least one of the position measurement devices 15 and 18, the movement amount of at least one of the machining head 13 and the stage 16 until the machining traces can be detected from the measurement results of the workpiece Wt using the measurement light ML. The calculated movement amount may be used as the amount of positional deviation between the target irradiation position PA and the target irradiation position MA.

[0099] As shown in FIG. 7 , the processing unit 1 may irradiate multiple locations within the processing shot area PSA with the processing light EL by changing the state of the galvanometer mirror 1341 (specifically, by changing the angle of at least one of the X-scanning mirror 1341X and the Y-scanning mirror 1341Y). As a result, processing marks are formed at each of the multiple locations within the processing shot area PSA. In this case, the processing unit 1 may irradiate the measurement light ML to the multiple processing marks formed at each of the multiple locations within the processing shot area PSA by changing the state of the galvanometer mirror 1341. Here, the processing shot area PSA typically coincides with or is included in the measurement shot area MSA. Therefore, it may be considered that the processing unit 1 irradiates the measurement light ML to the multiple processing marks formed at each of the multiple locations within the measurement shot area MSA by changing the state of the galvanometer mirror 1341. As a result, the control unit 2 can calculate the positional deviation amount between the target irradiation position PA and the target irradiation position MA at each of the multiple locations within the processing shot area PSA (i.e., the multiple locations within the measurement shot area MSA).

[0100] As described above, the processing optical system 131 includes the focusing position adjustment optical system 1313. In this case, the processing unit 1 may perform the same operation while changing the focusing position of the processing light EL and moving the processing head 13 along the Z-axis direction so that the changed focusing position of the processing light EL is located on the surface of the workpiece Wt. In other words, the processing unit 1 may form and measure processing marks each time it changes the focusing position of the processing light EL and moves the processing head 13 along the Z-axis direction so that the changed focusing position of the processing light EL is located on the surface of the workpiece Wt. As a result, the control unit 2 can calculate the positional deviation amount between the target irradiation position PA and the target irradiation position MA at each of multiple locations in the three-dimensional space where the processing unit 1 performs processing and measurement.

[0101] When the amount of positional deviation is calculated, the control unit 2 may control the machining unit 1 based on the amount of positional deviation. Specifically, the control unit 2 may control the machining unit 1 based on the amount of positional deviation to machine the workpiece W and measure the measurement object M in the same way as when no positional deviation occurs between the target irradiation position PA and the target irradiation position MA, even when a positional deviation occurs between the target irradiation position PA and the target irradiation position MA, based on the amount of positional deviation. In the movement error calculation operation and the deformation error calculation operation described below, the control unit 2 may control the machining unit 1 based on the amount of positional deviation to measure the reference member FM in the same way as when no positional deviation occurs between the target irradiation position PA and the target irradiation position MA, even when a positional deviation occurs between the target irradiation position PA and the target irradiation position MA. Typically, the control unit 2 may control the machining unit 1 to adjust the relationship between the target irradiation position PA and the target irradiation position MA based on the amount of positional deviation. In this case, the control unit 2 may control the machining unit 1 to machine the workpiece W and measure the measurement object M after adjusting the relationship between the target irradiation position PA and the target irradiation position MA based on the amount of positional deviation. For example, the control unit 2 may control the processing unit 1 based on the amount of positional deviation at each position within the processing shot area PSA so that the target irradiation position PA and the target irradiation position MA coincide with each other at each position within the processing shot area PSA. For example, the control unit 2 may control the processing unit 1 based on the amount of positional deviation at each position within the measurement shot area MSA so that the target irradiation position PA and the target irradiation position MA coincide with each other at each position within the measurement shot area MSA.

[0102] As one example, the target irradiation position PA on the workpiece W can be changed by the galvanometer mirror 1341. Therefore, the control unit 2 may control the galvanometer mirror 1341 so as to adjust the relationship between the target irradiation position PA and the target irradiation position MA by moving the target irradiation position PA. As another example, the target irradiation position PA on the workpiece W can be changed by at least one of the position adjustment optical system 1311 and the angle adjustment optical system 1312. Therefore, the control unit 2 may control at least one of the position adjustment optical system 1311 and the angle adjustment optical system 1312 so as to adjust the relationship between the target irradiation position PA and the target irradiation position MA by moving the target irradiation position PA. As another example, the target irradiation position PA on the workpiece W can be changed by moving at least one of the machining head 13 and the stage 16. Therefore, the control unit 2 may move at least one of the machining head 13 and the stage 16 so as to adjust the relationship between the target irradiation position PA and the target irradiation position MA by moving the target irradiation position PA. As another example, the target irradiation position MA on the measurement object M can be changed by at least one of the galvanometer mirrors 1341 and 1328. Therefore, the control unit 2 may control at least one of the galvanometer mirrors 1341 and 1328 so as to adjust the relationship between the target irradiation position PA and the target irradiation position MA by moving the target irradiation position MA. As another example, the target irradiation position MA on the measurement object M can be changed by moving at least one of the processing head 13 and the stage 16. Therefore, the control unit 2 may move at least one of the processing head 13 and the stage 16 so as to adjust the relationship between the target irradiation position PA and the target irradiation position MA by moving the target irradiation position MA.

[0103] (2-2) Movement error calculation operation Next, the movement error calculation operation will be described. As described above, the movement error calculation operation is an operation for calculating a movement error of at least one of the machining head 13 and the stage 16 using the measurement results of the reference member FM using the measurement light ML. Therefore, to perform the movement error calculation operation, the machining unit 1 may irradiate the reference member FM with the measurement light ML and receive the return light RL from the reference member FM. Furthermore, the control unit 2 may calculate the movement error based on the measurement results of the reference member FM by the machining unit 1 (i.e., the detection results of the return light RL from the reference member FM).

[0104] The reference member FM is any member that can be measured using the measurement light ML. The reference member FM may be any member for which the reference position of the reference member FM can be calculated from the measurement results of the reference member FM. Examples of the reference member FM are shown in FIGS. 8(a) to 8(c). As shown in FIG. 8(a), the reference member FM may be a member with a curved surface. In the example shown in FIG. 8(a), the reference member FM is a member including a sphere. In this case, for example, the position of the center of the sphere may be used as the reference position of the reference member FM. As shown in FIG. 8(b), the reference member FM may be a member with a flat surface. In the example shown in FIG. 8(b), the reference member FM is a member including a polyhedron. Examples of polyhedrons include at least one of a regular tetrahedron, a regular octahedron, a regular dodecahedron, and a regular tetradecahedron. In this case, for example, the position of the center of gravity of the polyhedron may be used as the reference position of the reference member FM. For example, the position where multiple line segments extending from multiple vertices of a polyhedron toward the centers of gravity of multiple faces opposite the multiple vertices intersect may be used as the reference position of the reference member FM. As shown in Figure 8(c), the reference member FM may be a member whose surface includes both flat and curved surfaces. In the example shown in Figure 8(c), the reference member FM is a member that includes two flat surfaces FMs1 facing opposite to each other and formed by removing parts of a sphere, and a curved surface FMs2 that forms the surface of the remaining part of the sphere that was not removed.

[0105] When the movement error calculation operation is performed, the reference member FM is placed on the stage 16. On the other hand, when the movement error calculation operation is not performed, the reference member FM does not have to be placed on the stage 16. As an example, the reference member FM may be detachably attached to the stage 16. In this case, when the movement error calculation operation is performed, the reference member FM may be attached to the stage 16. On the other hand, when the movement error calculation operation is not performed, the reference member FM may be removed from the stage 16. However, the reference member FM may be fixed to the stage 16 so that it cannot be removed from the stage 16. Note that when the reference member FM is fixed to the stage 16, a cover may be attached to isolate the reference member FM from the atmosphere in the processing chamber (the internal space SP of the housing 3) in order to reduce contamination of the reference member FM.

[0106] The reference member FM may be placed at any position on the stage 16. For example, the reference member FM may be placed on the mounting surface 161 of the stage 16. For example, the reference member FM may be placed on a surface different from the mounting surface 161 of the stage 16, for example, above the mounting surface 161 (the +Z-axis direction side of the mounting surface 161 when the mounting surface is positioned on the XY plane) or below the mounting surface 161 (the -Z-axis direction side of the mounting surface 161 when the mounting surface is positioned on the XY plane). However, as will be described in detail later, it is preferable that the reference member FM move in accordance with the movement (particularly, rotational movement) of the stage 16 in order to perform the movement error calculation operation. For this reason, the reference member FM may be located at a position away from the rotation axis of the stage 16 along a direction intersecting the rotation axis. For example, in this embodiment, the stage 16 is rotatable about a rotation axis AX along the A-axis and a rotation axis CX along the C-axis. For this reason, as shown in Figures 8(a) to 8(c), the reference member FM may be positioned at a position spaced apart from the rotation axis AX in a direction intersecting the rotation axis AX (in the example shown in Figures 8(a) to 8(c), the Y-axis direction), and at a position spaced apart from the rotation axis CX in a direction intersecting the rotation axis CX (in the example shown in Figures 8(a) to 8(c), the Y-axis direction).

[0107] As shown in FIGS. 9(a) and 9(b), under the control of the control unit 2, the machining unit 1 may measure a reference member FM located at position P1, and may also measure a reference member FM moved from position P1 to position P2 different from position P1. In this case, the control unit 2 may acquire from the machining unit 1 a detection result of return light RL from the reference member FM generated by irradiating the reference member FM located at position P1 with measurement light ML. Furthermore, the control unit 2 may acquire from the machining unit 1 a detection result of return light RL from the reference member FM generated by irradiating the reference member FM located at position P2 with measurement light ML. The control unit 2 may calculate a movement error based on the detection result of return light RL from the reference member FM located at position P1 and the detection result of return light RL from the reference member FM located at position P2.

[0108] As an example, because the reference member FM is placed on the stage 16, the reference member FM moves when the stage 16 moves. Therefore, the machining unit 1 may first measure the reference member FM located at position P1 by irradiating the reference member FM located at position P1 with a measurement light ML, as shown in FIG. 9(a). Then, as shown in FIG. 9(b), the machining unit 1 may move the stage 16 so that the reference member FM located at position P1 moves from position P1 to position P2, which is different from position P1. In this embodiment, because the stage 16 is movable in the rotational direction around the rotation axis AX along the A axis and the rotational direction around the rotation axis CX along the C axis, the positions P1 and P2 may differ in at least one of the rotational directions around the A axis and the C axis. Then, as shown in FIG. 9(b), the machining unit 1 may measure the reference member FM located at position P2 by irradiating the reference member FM located at position P2 with a measurement light ML. In this case, the machining unit 1 may measure the reference member FM located at position P2 by irradiating the reference member FM stopped at position P2 with measurement light ML. That is, the machining unit 1 may alternately measure the reference member FM, move the reference member FM, and stop the reference member FM. However, the machining unit 1 may also measure the reference member FM moving at position P2.

[0109] The machining unit 1 may further measure the reference member FM after it has moved from position P2 to a position different from positions P1 and P2. That is, the machining unit 1 may measure the reference member FM at three or more positions. For example, the machining unit 1 may rotate the stage 16 360 degrees around the rotation axis CX. During this process, the machining unit 1 may measure the reference member FM at three or more positions on a circumference that indicates the movement trajectory of the reference member FM. As an example, the machining unit 1 may measure the reference member FM each time the stage 16 rotates a predetermined angle around the rotation axis CX. For example, the machining unit 1 may rotate the stage 16 180 degrees around the rotation axis AX. For example, the machining unit 1 may rotate the stage 16 around the rotation axis AX in a range from -90 degrees to +90 degrees. The rotation angle of the stage 16 around the rotation axis AX may be defined so that the rotation angle is zero degrees when the mounting surface 161 of the stage 16 is parallel to the XY plane (i.e., perpendicular to the Z axis). During this process, the machining unit 1 may measure the reference member FM at three or more positions on a semicircle that indicates the movement trajectory of the reference member FM. As an example, the machining unit 1 may measure the reference member FM each time the stage 16 rotates a predetermined angle around the rotation axis AX.

[0110] The machining unit 1 may move the machining head 13 so that the machining head 13 follows the moving reference member FM. Specifically, the machining unit 1 may move the machining head 13 so that the moving reference member FM is included in a measurement shot area MSA that is determined based on the machining head 13. Specifically, as shown in FIG. 10(a), the machining unit 1 may irradiate the reference member FM located at position P1 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P4. Position P4 is a position that satisfies the condition that the reference member FM located at position P1 is included in the measurement shot area MSA of the machining head 13 located at position P4 (i.e., position P1 is included). Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P1 using the machining head 13 (particularly, the objective optical system 134) located at position P4. Thereafter, as shown in FIG. 10(b), the machining unit 1 may move the stage 16 so that the reference member FM located at position P1 moves from position P1 to position P2. Furthermore, as shown in FIG. 10(b), the machining unit 1 may move the machining head 13 located at position P4 so that the machining head 13 moves from position P4 to position P5 different from position P4. Position P5 is a position that satisfies the condition that the reference member FM located at position P2 is included in the measurement shot area MSA of the machining head 13 located at position P5 (i.e., position P2 is included). Thereafter, as shown in FIG. 10(b), the machining unit 1 may irradiate measurement light ML from the machining head 13 located at position P5 (particularly, the objective optical system 134) to the reference member FM located at position P2. Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P2 using the machining head 13 located at position P5 (particularly, the objective optical system 134). In this case, the machining unit 1 may measure the reference member FM located at position P2 using the machining head 13 stopped at position P5. In other words, the machining unit 1 may alternately measure the reference member FM, move the reference member FM and the machining head 13, and stop the reference member FM and the machining head 13.However, the machining unit 1 may measure the reference member FM located at position P2 using the machining head 13 moving at position P5.

[0111] As an example, when the stage 16 rotates around the rotation axis CX, the reference member FM typically moves within a plane along the XY plane, as shown in Fig. 11. Therefore, when the reference member FM moves within a plane along the XY plane as the stage 16 rotates around the rotation axis CX, the machining unit 1 may move the machining head 13 along at least one of the X-axis direction and the Y-axis direction so that the machining head 13 follows the moving reference member FM, as shown in Fig. 11. However, when the reference member FM moves within a plane along the XY plane as the stage 16 rotates around the rotation axis CX, the machining unit 1 may move the machining head 13 along the Z-axis direction in addition to or instead of at least one of the X-axis direction and the Y-axis direction.

[0112] As another example, when the stage 16 rotates around the rotation axis AX, the reference member FM typically moves within a plane along the YZ plane, as shown in Fig. 12. Therefore, when the reference member FM moves within a plane along the YZ plane as the stage 16 rotates around the rotation axis AX, the machining unit 1 may move the machining head 13 along at least one of the Y-axis direction and the Z-axis direction so that the machining head 13 follows the moving reference member FM, as shown in Fig. 12. However, when the reference member FM moves within a plane along the YZ plane as the stage 16 rotates around the rotation axis AX, the machining unit 1 may move the machining head 13 along the X-axis direction in addition to or instead of at least one of the Y-axis direction and the Z-axis direction.

[0113] 11 and 12, the machining unit 1 may be considered to be performing simultaneous three-axis control, which controls movement along three axes including two linear movement axes and one rotation axis. In this case, the operations shown in FIGS. 11 and 12 may be operations specified in ISO10791-6.2014, an international standard for calculating the movement error (motion error or motion accuracy) of a machine tool. However, the operations shown in FIGS. 11 and 12 differ from the operations specified in ISO10791-6.2014 in that a measurement device using a measurement light ML (i.e., a measurement device including a measurement optical system 132) is used instead of a measurement device including a ball bar or a displacement meter.

[0114] In this embodiment, the stage 16 does not rotate around a rotation axis along the B axis. However, if the stage 16 were rotatable around a rotation axis along the B axis, the reference member FM would typically move within a plane along the ZX plane. Therefore, if the reference member FM moves within a plane along the ZX plane as the stage 16 rotates around a rotation axis along the B axis, the machining unit 1 may move the machining head 13 along at least one of the Z axis and the X axis so that the machining head 13 follows the moving reference member FM. However, if the reference member FM moves within a plane along the ZX plane as the stage 16 rotates around a rotation axis along the B axis, the machining unit 1 may move the machining head 13 along the Y axis in addition to or instead of at least one of the Z axis and the X axis.

[0115] The machining unit 1 may move the machining head 13 so that the positional relationship between the moving reference member FM and the machining head 13 that moves to follow the reference member FM does not change. In other words, the machining unit 1 may move the machining head 13 so that the positional relationship between the moving reference member FM and the machining head 13 that moves to follow the reference member FM is maintained. For example, when the reference member FM moves as the stage 16 rotates around the rotation axis CX, the machining unit 1 may move the machining head 13 so that the positional relationship between the reference member FM that rotates and moves around the rotation axis CX and the machining head 13 does not change. Typically, the machining unit 1 may move the machining head 13 along at least one of the X-axis direction and the Y-axis direction so that the movement trajectory of the machining head 13 in a plane along the XY plane describes an arc around the rotation axis CX. For example, when the reference member FM moves as the stage 16 rotates around the rotation axis AX, the machining unit 1 may move the machining head 13 so that the positional relationship between the reference member FM that rotates and moves around the rotation axis AX and the machining head 13 does not change. Typically, the machining unit 1 may move the machining head 13 along at least one of the Y-axis direction and the Z-axis direction so that the movement trajectory of the machining head 13 in a plane along the YZ plane describes an arc around the rotation axis AX. In this case, the control unit 2 may move the machining head 13 by performing circular interpolation control.

[0116] Note that a state in which the positional relationship between the reference member FM and the machining head 13 does not change may mean a state in which the positional relationship between the reference position of the reference member FM and the machining head 13 does not change. A state in which the positional relationship between the reference member FM and the machining head 13 does not change may mean a state in which the relationship between the three-dimensional coordinates of the reference member FM and the three-dimensional coordinates of the machining head 13 in three-dimensional space does not change. When the positional relationship between the reference member FM and the machining head 13 does not change, the orientation of the reference member FM relative to the machining head 13 may change as the stage 16 rotates. The orientation of the machining head 13 relative to the reference member FM may change as the stage 16 rotates. Alternatively, the orientation of the reference member FM relative to the machining head 13 may not change regardless of the rotation of the stage 16. The orientation of the machining head 13 relative to the reference member FM may not change as the stage 16 rotates.

[0117] Note that when the machining head 13 moves to track the reference member FM, as shown in FIG. 13 , the machining head 13 does not necessarily have to be positioned directly above the reference member FM. Specifically, the machining head 13 does not necessarily have to be positioned at a position where the optical axis EX of the fθ lens 1342 overlaps with the reference member FM. Essentially, the machining head 13 only needs to be positioned at a position where the reference member FM is included in the measurement shot area MSA. Similarly, even when the machining head 13 does not move, the machining head 13 does not necessarily have to be positioned directly above the reference member FM. In this case, the movement amount of the machining head 13 in one movement direction may be greater or smaller than the movement amount of the reference member FM in the same movement direction. In the example shown in FIG. 13 , the movement amount of the reference member FM in the Y-axis direction is greater than the movement amount of the reference member FM in the Y-axis direction due to movement of the stage 16 around the rotation axis CX of the machining head 13.

[0118] However, the machining unit 1 does not have to move the machining head 13 so that the machining head 13 follows the moving reference member FM. For example, even when the machining head 13 does not move, the machining unit 1 does not have to move the machining head 13 so that the moving reference member FM is included in the measurement shot area MSA. In this case, as shown in FIG. 14 , the machining unit 1 may irradiate the measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P3 onto the reference member FM located at position P1. Furthermore, the machining unit 1 may receive the return light RL from the reference member FM located at position P1 using the machining head 13 (particularly, the objective optical system 134) located at position P3. Thereafter, the machining unit 1 may move the stage 16 so that the reference member FM located at position P1 moves from position P1 to position P2. Thereafter, the machining unit 1 may irradiate the measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P3 onto the reference member FM located at position P2. Furthermore, the processing unit 1 may use the processing head 13 (particularly the objective optical system 134) located at position P3 to receive return light RL from the reference member FM located at position P2. Therefore, position P3 is a position that satisfies the condition that the measurement shot area MSA of the processing head 13 located at position P3 includes both the reference member FM located at position P1 and the reference member FM located at position P2 (that is, includes both positions P1 and P2).

[0119] After completing the measurement of the reference member FM, the control unit 2 may calculate a movement error occurring in the movement of at least one of the machining head 13 and the stage 16 based on the measurement results of the reference member FM. Specifically, the control unit 2 may calculate the position of the reference member FM (particularly, the reference position) based on the measurement results of the reference member FM. That is, the control unit 2 may generate measurement data (i.e., position information) indicating the position of the reference member FM. In particular, because the reference member FM moves, the control unit 2 may calculate the movement trajectory of the reference member FM (particularly, the movement trajectory of the reference position). That is, the control unit 2 may generate measurement data indicating the movement trajectory of the reference member FM. Note that examples of measurement data indicating the calculated position of the reference member FM (particularly, the movement trajectory) are shown in FIGS. 15(a) to 15(c). FIGS. 15(a) to 15(c) show the position (three-dimensional position) of the reference member FM measured every time the stage 16 is rotated 30 degrees around the rotation axis CX. In particular, Figure 15(a) shows the position (three-dimensional position) of the reference member FM projected onto the XY plane. Figure 15(b) shows the position (three-dimensional position) of the reference member FM projected onto the YZ plane. Figure 15(c) shows the position (three-dimensional position) of the reference member FM projected onto the ZX plane. Thereafter, the control unit 2 may calculate a movement error based on the calculated position of the reference member FM (i.e., the measurement data, which is position information).

[0120] Specifically, the shape of the movement trajectory of the reference member FM when no movement error occurs differs from the shape of the movement trajectory of the reference member FM when a movement error occurs. For example, when the stage 16 is rotated around the rotation axis CX, the shape of the movement trajectory of the reference member FM in the XY plane when no movement error occurs is a perfect circle, whereas the shape of the movement trajectory of the reference member FM in the XY plane when a movement error occurs is a shape other than a perfect circle. For example, when the stage 16 is rotated around the rotation axis CX, the shape of the movement trajectory of the reference member FM in the YZ plane when no movement error occurs is a straight line parallel to the Y axis, whereas the shape of the movement trajectory of the reference member FM in the YZ plane when a movement error occurs is a shape other than a straight line parallel to the Y axis. For example, when the stage 16 is rotated around the rotation axis CX, the shape of the movement trajectory of the reference member FM in the ZX plane when no movement error occurs is a straight line parallel to the X axis, whereas the shape of the movement trajectory of the reference member FM in the ZX plane when a movement error occurs is a shape other than a straight line parallel to the X axis. 15(a) to 15(c) show the calculation results of the position of the reference member FM when a movement error occurs. Therefore, the control unit 2 can calculate the movement error based on the position of the reference member FM. As an example, if the machining head 13 does not move when measuring the reference member FM (i.e., the machining head 13 is fixed and does not follow the reference member FM), it can be seen from the position of the reference member FM shown in FIGS. 15(b) and 15(c) that a movement error may have occurred in which the rotation axis CX is tilted with respect to the Z axis. In other words, the control unit 2 can calculate the movement error of the stage 16 from the position of the reference member FM shown in FIGS. 15(b) and 15(c). As another example, when the machining head 13 moves (i.e., follows the reference member FM) when measuring the reference member FM under conditions where the movement error of the machining head 13 is small enough to be ignored (i.e., the movement accuracy of the machining head 13 is very high), it can be seen from the position of the reference member FM shown in Figures 15(b) and 15(c) that a movement error may occur in which the rotation axis CX is tilted with respect to the Z axis.That is, the control unit 2 can calculate the movement error of the stage 16 from the position of the reference member FM shown in Figures 15(b) and 15(c). Conversely, if the machining head 13 moves (i.e., follows the reference member FM) when measuring the reference member FM under circumstances where the movement error of the stage 16 is negligibly small (i.e., the rotation accuracy of the stage 16 is very high), the control unit 2 may calculate the movement error of the machining head 13 from the position of the reference member FM shown in Figures 15(b) and 15(c). As another example, if the machining head 13 moves (i.e., follows the reference member FM) when measuring the reference member FM under circumstances where the movement error of the machining head 13 is known to the control unit 2, it can be seen from the position of the reference member FM shown in Figures 15(b) and 15(c) and the information regarding the movement error of the machining head 13 that a movement error may have occurred, in which the rotation axis CX is tilted with respect to the Z axis.

[0121] The movement error occurring in the movement of the machining head 13 may include an error corresponding to the difference (i.e., deviation) between the actual movement amount of the machining head 13 in one movement direction and the target value of the movement amount of the machining head 13 in the position movement direction when the head drive system 14 moves the machining head 13 along one movement direction. The movement error occurring in the movement of the machining head 13 may include an error corresponding to the actual movement amount of the machining head 13 in another movement direction different from the one movement direction when the head drive system 14 moves the machining head 13 along the one movement direction. For example, when the head drive system 14 moves the machining head 13 so that the machining head 13 moves only along one movement direction, ideally the machining head 13 will not move along the other movement directions. Therefore, when the machining head 13 that should move in one movement direction actually moves along the other movement direction, a movement error of the machining head 13 in the other movement direction occurs.

[0122] As described above, the head drive system 14 moves the processing head 13 along the X-axis direction. In this case, the movement error occurring in the movement of the processing head 13 is expressed as the movement error E X The movement error E X is the movement error E in the X-axis direction XX and the Y-axis movement error E YX and the Z-axis movement error E ZX and the rotational movement error around the A axis, E AX and the rotational movement error around the B axis E BX and the rotational movement error around the C axis E CX The movement error E XX The movement error E may be the difference between the actual movement amount of the machining head 13 in the X-axis direction and the target value of the movement amount of the machining head 13 in the X-axis direction when the head drive system 14 moves the machining head 13 along the X-axis direction. YX may be the actual movement amount of the machining head 13 in the Y-axis direction when the head drive system 14 moves the machining head 13 along the X-axis direction. ZX may be the actual movement amount of the machining head 13 in the Z-axis direction when the head drive system 14 moves the machining head 13 along the X-axis direction. AX may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the A axis when the head drive system 14 moves the machining head 13 along the X axis direction. BX may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the B axis when the head drive system 14 moves the machining head 13 along the X axis direction. CX may be the actual movement amount (rotation amount) of the processing head 13 in the rotation direction around the C axis when the head drive system 14 moves the processing head 13 along the X axis direction.

[0123] As described above, the head drive system 14 moves the processing head 13 along the Y-axis direction. In this case, the movement error occurring in the movement of the processing head 13 is expressed as the movement error E Y The movement error E Y is the movement error E in the X-axis direction XY and the Y-axis movement error E YY and the Z-axis movement error E ZY and the rotational movement error around the A axis, E AY and the rotational movement error around the B axis E BY and the rotational movement error around the C axis E CY The movement error E XY may be the actual movement amount of the machining head 13 in the X-axis direction when the head drive system 14 moves the machining head 13 along the Y-axis direction. YY The movement error E may be the difference between the actual movement amount of the machining head 13 in the Y-axis direction and the target value of the movement amount of the machining head 13 in the Y-axis direction when the head drive system 14 moves the machining head 13 along the Y-axis direction. ZY may be the actual movement amount of the machining head 13 in the Z-axis direction when the head drive system 14 moves the machining head 13 along the Y-axis direction. AY may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the A axis when the head drive system 14 moves the machining head 13 along the Y axis direction. BY may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the B axis when the head drive system 14 moves the machining head 13 along the Y axis direction. CY may be the actual movement amount (rotation amount) of the processing head 13 in the rotation direction around the C axis when the head drive system 14 moves the processing head 13 along the Y axis direction.

[0124] As described above, the head drive system 14 moves the processing head 13 along the Z-axis direction. In this case, the movement error occurring in the movement of the processing head 13 may be calculated as the movement error occurring in the movement of the processing head 13 when the processing head 13 moves along the Z-axis direction (linear movement). The movement error E Z is the movement error E in the X-axis direction XZ and the Y-axis movement error E YZ and the Z-axis movement error E ZZ and the rotational movement error around the A axis, E AZ and the rotational movement error around the B axis E BZ and the rotational movement error around the C axis E CZ The movement error E XZ may be the actual movement amount of the machining head 13 in the X-axis direction when the head drive system 14 moves the machining head 13 along the Z-axis direction. YZ may be the actual movement amount of the machining head 13 in the Y-axis direction when the head drive system 14 moves the machining head 13 along the Z-axis direction. ZZ The movement error E may be the difference between the actual movement amount of the machining head 13 in the Z-axis direction and the target value of the movement amount of the machining head 13 in the Z-axis direction when the head drive system 14 moves the machining head 13 along the Z-axis direction. AZ may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the A axis when the head drive system 14 moves the machining head 13 along the Z axis direction. BZ may be the actual movement amount (rotation amount) of the machining head 13 in the rotation direction around the B axis when the head drive system 14 moves the machining head 13 along the Z axis direction. CZ may be the actual movement amount (rotation amount) of the processing head 13 in the rotation direction around the C axis when the head drive system 14 moves the processing head 13 along the Z axis direction.

[0125] The movement error occurring in the movement of the stage 16 may include an error corresponding to the difference (i.e., deviation) between the actual movement amount of the stage 16 in one movement direction and the target value of the movement amount of the stage 16 in the position movement direction when the stage drive system 17 moves the stage 16 along one movement direction. The movement error occurring in the movement of the stage 16 may include an error corresponding to the actual movement amount of the stage 16 in another movement direction different from the one movement direction when the stage drive system 17 moves the stage 16 along the one movement direction. For example, if the stage drive system 17 moves the stage 16 so that the stage 16 moves only along one movement direction, ideally the stage 16 will not move along another movement direction. Therefore, if the stage 16 that should move in one movement direction actually moves along another movement direction, a movement error of the stage 16 in the other movement direction occurs.

[0126] As described above, the stage drive system 17 moves the stage 16 in the rotation direction around the A axis. In this case, the movement error occurring in the movement of the stage 16 is the movement error E A The movement error E A is the movement error E in the X-axis direction XA and the Y-axis movement error E YA and the Z-axis movement error E ZA and the rotational movement error around the A axis, E AA and the rotational movement error around the B axis E BA and the rotational movement error around the C axis E CA The movement error E XA may be the actual movement amount of the stage 16 in the X-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the A-axis. YA may be the actual movement amount of the stage 16 in the Y-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the A-axis. ZAmay be the actual movement amount of the stage 16 in the Z-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the A-axis. AA The movement error E may be the difference between the actual movement amount of the stage 16 in the rotation direction around the A axis and the target value of the movement amount of the stage 16 in the rotation direction around the A axis when the stage drive system 17 moves the stage 16 in the rotation direction around the A axis. BA may be the actual movement (rotation) amount of the stage 16 in the rotation direction around the B axis when the stage drive system 17 moves the stage 16 in the rotation direction around the A axis. CA may be the actual movement amount (rotation amount) of the stage 16 in the rotation direction around the C axis when the stage drive system 17 moves the stage 16 in the rotation direction around the A axis.

[0127] As described above, the stage drive system 17 moves the stage 16 in the rotation direction around the C axis. In this case, the movement error occurring in the movement of the stage 16 is the movement error E C The movement error E C is the movement error E in the X-axis direction XC and the Y-axis movement error E YC and the Z-axis movement error E ZC and the rotational movement error around the A axis, E AC and the rotational movement error around the B axis E BC and the rotational movement error around the C axis E CC The movement error E XC may be the actual movement amount of the stage 16 in the X-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the C-axis. YC may be the actual movement amount of the stage 16 in the Y-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the C-axis. ZCmay be the actual movement amount of the stage 16 in the Z-axis direction when the stage drive system 17 moves the stage 16 in the rotation direction around the C-axis. AC may be the actual movement amount (rotation amount) of the stage 16 in the rotation direction around the A axis when the stage drive system 17 moves the stage 16 in the rotation direction around the XC axis. BC may be the actual movement (rotation) amount of the stage 16 in the rotation direction around the B axis when the stage drive system 17 moves the stage 16 in the rotation direction around the C axis. CC may be the difference between the actual movement amount of the stage 16 in the rotation direction around the C axis and the target value of the movement amount of the stage 16 in the rotation direction around the C axis when the stage drive system 17 moves the stage 16 in the rotation direction around the C axis.

[0128] When the stage drive system 17 rotates the stage 16 in the rotation direction around the A axis, the machining unit 1 may measure a reference member FM placed on the stage 16 rotating in the rotation direction around the A axis. In this case, the control unit 2 may calculate the rotation center coordinate of the stage 16 around the A axis (i.e., the position of the A axis) based on the measurement results of the reference member FM. Similarly, when the stage drive system 17 rotates the stage 16 in the rotation direction around the C axis, the machining unit 1 may measure the reference member FM placed on the stage 16 rotating in the rotation direction around the C axis. In this case, the control unit 2 may calculate the rotation center coordinate of the stage 16 around the C axis (i.e., the position of the C axis) based on the measurement results of the reference member FM. In this way, the control unit 2 may calculate the rotation center coordinate of the stage 16 around one rotation axis (i.e., the position of one rotation axis) based on the measurement results of the reference member FM placed on the stage 16 rotating in the rotation direction around one rotation axis.

[0129] The movement error may include an error relating to the relationship between the movement axis of the processing head 13 and the movement axis (rotation axis) of the stage 16. For example, the movement error may include an error relating to the orthogonality (squareness) between the movement axis of the processing head 13 and the rotation axis of the stage 16. For example, the movement error may include an error relating to the parallelism between the movement axis of the processing head 13 and the rotation axis of the stage 16.

[0130] The movement error may include an error related to the movement axis of the machining head 13. For example, the movement error may include an error related to the orthogonality (perpendicularity) between one movement axis of the machining head 13 and another movement axis.

[0131] The movement error may include an error related to the movement axis (rotation axis) of the stage 16. For example, the movement error may include an error related to the orthogonality (perpendicularity) between one rotation axis of the stage 16 and another rotation axis.

[0132] The operation of calculating the movement error based on the position of the reference member FM may be the same as the operation of calculating the movement error (i.e., the motion error) based on the position of the ball bar or reference sphere specified in ISO 10791-6.2014. In other words, the operation of calculating the movement error based on the position of the reference member FM may be the same as the measurement using a ball bar or the so-called R-test measurement.

[0133] As an example, the control unit 2 may calculate the movement error appearing in the position of the reference member FM by analyzing the position (e.g., the movement trajectory) of the reference member FM. In other words, the control unit 2 may analyze the position (e.g., the movement trajectory) of the reference member FM to identify the cause of the deviation of the position of the reference member FM from the ideal position, and calculate the movement error related to the cause.

[0134] As another example, if the movement accuracy of the machining head 13 is higher than that of the stage 16, the position of the reference member FM may be considered to be more affected by movement errors occurring in the movement of the stage 16 than by movement errors occurring in the movement of the machining head 13. In this case, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 based on the position of the reference member FM. For example, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 along the rotation direction around the C-axis based on the position of the reference member FM measured while rotating the stage 16 around the rotation axis CX. For example, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 along the rotation direction around the A-axis based on the position of the reference member FM measured while rotating the stage 16 around the rotation axis AX. As an example, the measurement data shown in Figures 15(b) and 15(c) indicate that the rotation axis CX of the stage 16 is not perpendicular to the movement axis (X-axis or Y-axis) of the machining head 13. Therefore, the control unit 2 may calculate the error regarding the orthogonality between the rotation axis CX of the stage 16 and the movement axis (X-axis or Y-axis) of the processing head 13 based on the measurement data shown in Figures 15(b) and 15(c).

[0135] As another example, if the machining head 13 does not move when measuring the reference member FM, the position of the reference member FM is not affected by errors occurring in the movement of the machining head 13, but is affected by movement errors occurring in the movement of the stage 16. In this case, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 based on the position of the reference member FM. For example, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 along the rotation direction about the C-axis based on the position of the reference member FM measured while rotating the stage 16 around the rotation axis CX. For example, the control unit 2 may calculate the movement errors occurring in the movement of the stage 16 along the rotation direction about the A-axis based on the position of the reference member FM measured while rotating the stage 16 around the rotation axis AX.

[0136] As another example, if the movement accuracy of the stage 16 is higher than the movement accuracy of the machining head 13, the position of the reference member FM may be considered to be more affected by movement errors occurring in the movement of the machining head 13 than by movement errors occurring in the movement of the stage 16. In this case, the control unit 2 may calculate the movement errors occurring in the movement of the machining head 13 based on the position of the reference member FM. For example, the control unit 2 may calculate the movement errors occurring in the movement of the machining head 13 along the X-axis direction based on the position of the reference member FM measured while moving the machining head 13 along the X-axis direction. For example, the control unit 2 may calculate the movement errors occurring in the movement of the machining head 13 along the Y-axis direction based on the position of the reference member FM measured while moving the machining head 13 along the Y-axis direction. For example, the control unit 2 may calculate the movement errors occurring in the movement of the machining head 13 along the Z-axis direction based on the position of the reference member FM measured while moving the machining head 13 along the Z-axis direction.

[0137] When a movement error is calculated, the control unit 2 may control the machining unit 1 based on the movement error. Specifically, even when a movement error occurs, the control unit 2 may control the machining unit 1 so that the workpiece W is machined and the measurement object M is measured in the same way as when no movement error occurs. For example, even when a movement error occurs, the control unit 2 may control the head drive system 14 that moves the machining head 13 so that the machining head 13 moves in the same way as when no movement error occurs. In other words, the control unit 2 may move the machining head 13 so that the movement error is canceled out. For example, even when a movement error occurs, the control unit 2 may control the stage drive system 17 that moves the stage 16 so that the stage 16 moves in the same way as when no movement error occurs. In other words, the control unit 2 may move the stage 16 so that the movement error is canceled out. Furthermore, since the movement error is calculated from information regarding the position of the reference member FM, the control unit 2 may be considered to be controlling the movement of at least one of the processing head 13 and the stage 16 based on information regarding the position of the reference member FM (i.e., controlling at least one of the head drive system 14 and the stage drive system 17).

[0138] The control unit 2 may store movement error information relating to the calculated movement error in a storage device included in the control unit 2. The control unit 2 may store movement error information relating to the calculated movement error in a storage device arranged outside the control unit 2. In this case, the control unit 2 may control the machining unit 1 based on the movement error information stored in the storage device.

[0139] The control unit 2 may store the movement error information in the storage device together with temperature information regarding the temperature of the machining unit 1 during the measurement period in which the reference member FM was measured to calculate the movement error. The temperature of the machining unit 1 may include the temperature of the environment in which the machining unit 1 is installed (e.g., the temperature of the internal space SP in which the machining unit 1 is housed). The temperature of the machining unit 1 may also include the temperature of components included in the machining unit 1 (e.g., at least one of the machining head 13, the head drive system 14, the stage 16, and the stage drive system 17). The temperature information may include information regarding statistical values ​​of the temperature of the machining unit 1 during the measurement period (e.g., at least one of the maximum value, minimum value, average value, and median value). The control unit 2 may store, in the storage device, multiple pieces of movement error information corresponding to multiple environments in which the machining unit 1 has different temperatures, together with the temperature information. In this case, the control unit 2 may control the machining unit 1 based on one piece of movement error information corresponding to the temperature closest to the current temperature of the machining unit 1.

[0140] The machining system SYS may perform such a movement error calculation operation at regular intervals. For example, the machining system SYS may perform the movement error calculation operation every n1 (where n1 is an integer greater than or equal to 1) days. For example, the machining system SYS may perform the movement error calculation operation every n2 (where n2 is an integer greater than or equal to 1) weeks. For example, the machining system SYS may perform the movement error calculation operation every n3 (where n3 is an integer greater than or equal to 1) months. For example, the machining system SYS may perform the movement error calculation operation every n4 (where n4 is an integer greater than or equal to 1) years. For example, the machining system SYS may perform the movement amount error calculation operation every n5 (where n5 is an integer greater than or equal to 1) hours.

[0141] As described above, in the present embodiment, the control unit 2 can calculate the movement error occurring in the movement of at least one of the machining head 13 and the stage 16. Therefore, under the control of the control unit 2, the machining unit 1 can machine the workpiece W and the measurement object M while reducing the influence of the movement error. In particular, in the present embodiment, since the reference member FM is measured using the measurement light ML emitted from the machining head 13, there is no need to attach a dedicated measuring device (e.g., a displacement meter specified in ISO10791-6.2014) for measuring the reference member FM. Therefore, the control unit 2 can calculate the position of the reference member FM with relatively high accuracy without being affected by the installation error resulting from the installation of the measuring device. As a result, the control unit 2 can calculate the movement error with relatively high accuracy. Therefore, under the control of the control unit 2, the machining unit 1 can machine the workpiece W and the measurement object M while more appropriately reducing the influence of the movement error.

[0142] (2-3) Deformation error calculation operation Next, the deformation error calculation operation will be described. As described above, the deformation error calculation operation is an operation for calculating a movement error that occurs in the movement of at least one of the machining head 13 and the stage 16 due to deformation of a member included in the machining unit 1.

[0143] Specifically, the members (hereinafter referred to as "head drive members") included in the head drive system 14 that moves the machining head 13 may be deformed due to changes in the temperature of the machining unit 1. Examples of head drive members include at least one of an X guide member (in other words, an X rail member) that extends along the X axis to move the machining head 13 along the X axis, a Y guide member (in other words, a Y rail member) that extends along the Y axis to move the machining head 13 along the Y axis, and a Z guide member (in other words, a Z rail member) that extends along the Z axis to move the machining head 13 along the Z axis. For example, the head drive member may expand due to an increase in temperature. For example, the head drive member may contract due to a decrease in temperature. That is, thermal expansion or thermal contraction of the head drive member may occur. In this case, a movement error may occur in the movement of the machining head 13 due to deformation (e.g., thermal expansion or thermal contraction) of the head drive member.

[0144] Similarly, the members (hereinafter referred to as "stage driving members") included in the stage driving system 17 that moves the stage 16 may be deformed due to changes in the temperature of the processing unit 1. For example, the stage driving members may expand due to an increase in temperature. For example, the stage driving members may expand due to a decrease in temperature. In other words, thermal expansion or thermal contraction of the stage driving members may occur. In this case, a movement error may occur in the movement of the stage 16 due to deformation (e.g., thermal expansion or thermal contraction) of the stage driving members.

[0145] Therefore, in this embodiment, the processing system SYS performs a deformation error calculation operation to calculate a movement error that occurs in the movement of at least one of the processing head 13 and the stage 16 due to deformation of a component (for example, at least one of the head driving component and the stage driving component) provided in the processing unit 1.

[0146] Here, in a processing system (e.g., a general 5-axis processing machine) in which both the processing head for processing the workpiece W and the stage on which the workpiece W is placed move, the movement accuracy of the stage is likely to be sufficiently higher than the movement accuracy of the processing head. In this case, the movement error of the stage can be considered to be negligibly small. In other words, the stage can be considered to move extremely accurately. In this case, the processing system SYS can accurately calculate the movement error occurring in the movement of the processing head by performing a deformation error calculation operation. Therefore, in the following explanation, for simplicity, a deformation error calculation operation for calculating the movement error occurring in the movement of the processing head 13 due to deformation of the head drive member will be described. However, the processing system SYS may also calculate the movement error occurring in the movement of the stage 16 due to deformation of the stage drive member by performing an operation similar to the deformation error calculation operation described below.

[0147] The deformation error calculation operation will be described below with reference to Fig. 16. Fig. 16 is a flowchart showing the flow of the deformation error calculation operation.

[0148] As shown in FIG. 16, first, the above-mentioned reference member FM is placed on the stage 16 (step S11).

[0149] Thereafter, the control unit 2 calculates the position of the reference member FM on the stage 16 (step S12). In this embodiment, an example will be described in which the control unit 2 calculates the radius of rotation R of the reference member FM around the rotation axis CX as an index value indicating the position of the reference member FM on the stage 16. In this case, the control unit 2 may calculate the radius of rotation R by performing at least one of a first radius calculation operation and a second radius calculation operation. Below, the first and second radius calculation operations will be described in order.

[0150] First, the first radius calculation operation will be described. In this case, as shown in FIGS. 17(a) and 17(b), the machining unit 1 rotates the stage 16 around the rotation axis AX under the control of the control unit 2. In this case, the machining unit 1 may rotate the stage 16 around the rotation axis AX so that the mounting surface 161 on which the reference member FM is placed is parallel to the Z-axis direction (i.e., the direction of gravity). The machining unit 1 may rotate the stage 16 around the rotation axis AX so that the mounting surface 161 becomes a surface along the traveling direction of the measurement light ML emitted from the machining head 13 (the Z-axis direction in the example shown in FIGS. 17(a) and 17(b)). The machining unit 1 may rotate the stage 16 around the rotation axis AX so that the rotation axis CX perpendicular to the mounting surface 161 is perpendicular to the Z-axis direction.

[0151] 18(a) to 18(d), under the control of the control unit 2, the machining unit 1 may measure the reference member FM located at position P8, and may also measure the reference member FM moved from position P8 to position P9 different from position P8. In this case, the control unit 2 may acquire, from the machining unit 1, a detection result of the return light RL from the reference member FM generated by irradiating the reference member FM located at position P8 with the measurement light ML. Furthermore, the control unit 2 may acquire, from the machining unit 1, a detection result of the return light RL from the reference member FM generated by irradiating the reference member FM located at position P9 with the measurement light ML. The control unit 2 may calculate the radius of rotation R based on the detection result of the return light RL from the reference member FM located at position P8 and the detection result of the return light RL from the reference member FM located at position P9.

[0152] Specifically, the machining unit 1 may first measure the reference member FM located at position P8 by irradiating the reference member FM located at position P8 with measurement light ML, as shown in FIGS. 18(a) and 18(b). Then, the machining unit 1 may rotate the stage 16 around the rotation axis CX so that the reference member FM located at position P8 moves from position P8 to position P9 different from position P8, as shown in FIGS. 18(c) and 18(d). Then, the machining unit 1 may measure the reference member FM located at position P9 by irradiating the reference member FM located at position P9 with measurement light ML, as shown in FIGS. 18(c) and 18(d). In this case, the machining unit 1 may measure the reference member FM located at position P9 by irradiating the reference member FM stopped at position P9 with measurement light ML. In other words, the machining unit 1 may alternately measure the reference member FM, move (rotate) the reference member FM, and stop the reference member FM. However, the machining unit 1 may measure the reference member FM that is moving at the position P9.

[0153] Positions P8 and P9 may satisfy a first position condition that positions P8 and P9 are aligned along the traveling direction of the measurement light ML. Conversely, the machining unit 1 may rotate the stage 16 around the rotation axis CX so that positions P8 and P9 satisfy the first position condition. In the example shown in FIGS. 18(a) to 18(d), the traveling direction of the measurement light ML is the Z-axis direction. In this case, the machining unit 1 may rotate the stage 16 around the rotation axis CX so that positions P8 and P9 are aligned along the Z-axis direction.

[0154] Positions P8 and P9 may satisfy a second position condition that positions P8 and P9 are located at the same position in a direction along a plane intersecting the traveling direction of the measurement light ML and are located at different positions in a direction along the traveling direction of the measurement light ML. Conversely, the machining unit 1 may rotate the stage 16 around the rotation axis CX so that positions P8 and P9 satisfy the second position condition. In the example shown in FIGS. 18(a) to 18(d), the traveling direction of the measurement light ML is the Z-axis direction. In this case, the machining unit 1 may rotate the stage 16 around the rotation axis CX so that positions P8 and P9 are located at the same position in a direction along an XY plane intersecting the Z-axis direction (e.g., at least one of the X-axis direction and the Y-axis direction) (so that the X coordinate and the Y coordinate are the same). 18(a) to 18(d), the machining unit 1 rotates the stage 16 about the rotation axis CX so that positions P8 and P9 are located at the same positions in both the X-axis direction and the Y-axis direction. Furthermore, the machining unit 1 may rotate the stage 16 about the rotation axis CX so that positions P8 and P9 are located at different positions in the Z-axis direction. In the example shown in FIGS. 18(a) to 18(d), the machining unit 1 rotates the stage 16 about the rotation axis CX so that position P8 is located above position P9 along the Z-axis direction.

[0155] Positions P8 and P9 may satisfy a third position condition that positions P8 and P9 are located at two positions where a circle C (see FIGS. 18(b) and 18(d)) centered on the rotation axis CX intersects with a straight line L (see FIGS. 18(b) and 18(d)) passing through the center of the circle (i.e., the rotation axis CX). Conversely, the processing unit 1 may rotate the stage 16 around the rotation axis CX so that positions P8 and P9 satisfy the third position condition.

[0156] When positions P8 and P9 satisfy both the first and third position conditions, as shown in FIGS. 18(a) and 18(b), position P8 corresponds to the uppermost position on the movement trajectory of the reference member FM when the stage 16 rotates around the rotation axis CX. On the other hand, as shown in FIGS. 18(c) and 18(d), position P9 corresponds to the lowermost position on the movement trajectory of the reference member FM when the stage 16 rotates around the rotation axis CX. In this case, the machining unit 1 may move the reference member FM located at position P8 to position P9 by rotating the stage 16 by 180 degrees around the rotation axis CX. Note that when positions P8 and P9 satisfy the first and third position conditions, positions P8 and P9 necessarily satisfy the second position condition.

[0157] In the first radius calculation operation, it is preferable that positions P8 and P9 satisfy the first and third position conditions. In this case, the machining unit 1 may rotate the stage 16 about the rotation axis AX so that the mounting surface 161 on which the reference member FM is placed is parallel to the Z-axis direction, and then, if necessary, rotate the stage 16 about the rotation axis CX so that the reference member FM is located at position P8, which is the uppermost position on the movement trajectory of the reference member FM when the stage 16 rotates about the rotation axis CX. The machining unit 1 may then measure the reference member FM located at position P8. The machining unit 1 may then rotate the stage 16 180 degrees about the rotation axis CX to move the reference member FM located at position P8 to position P9, which is the lowermost position on the movement trajectory of the reference member FM when the stage 16 rotates about the rotation axis CX. The machining unit 1 may then measure the reference member FM located at position P9.

[0158] The machining unit 1 may measure both the reference member FM located at position P8 and the reference member FM located at position P9 without moving the machining head 13. Specifically, as shown in FIGS. 18(a) and 18(b), the machining unit 1 may irradiate the reference member FM located at position P8 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P12. Furthermore, the machining unit 1 may receive the return light RL from the reference member FM located at position P8 using the machining head 13 (particularly, the objective optical system 134) located at position P12. Furthermore, as shown in FIGS. 18(c) and 18(d), the machining unit 1 may irradiate the reference member FM located at position P9 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P12. Furthermore, the machining unit 1 may receive the return light RL from the reference member FM located at position P9 using the machining head 13 (particularly, the objective optical system 134) located at position P12. In this case, position P12 is a position that satisfies the condition that the measurement shot area MSA of the processing head 13 located at position P12 includes both the reference member FM located at position P8 and the reference member FM located at position P9 (i.e., includes both positions P8 and P9).

[0159] After completing the measurement of the reference member FM, the control unit 2 may calculate the radius of rotation R based on the measurement results of the reference member FM. Specifically, the control unit 2 may calculate the distance from the machining head 13 to the reference member FM based on the measurement results of the reference member FM. That is, as shown in FIGS. 19(a) and 19(b), the control unit 2 may calculate a distance d81 from the machining head 13 to the reference member FM located at position P8 and a distance d91 from the machining head 13 to the reference member FM located at position P9. Here, because positions P8 and P9 correspond to the uppermost and lowermost positions on the movement trajectory of the reference member FM, respectively, as shown in FIGS. 19(a) and 19(b), the difference between the distance d81 and the distance d91 (i.e., d91 - d81) is equal to twice the radius of rotation R. Therefore, the control unit 2 may calculate the radius of rotation R using the formula R = (d91 - d81) / 2.

[0160] In addition to or instead of measuring the reference member FM located at position P8 and the reference member FM located at position P9, the machining unit 1 may measure the reference member FM multiple times while the stage 16 is rotating 360 degrees around the rotation axis CX. In this case, as shown in FIG. 20 , the control unit 2 may calculate the relationship between the rotation angle of the stage 16 around the rotation axis CX and the distance from the machining head 13 to the reference member FM based on the measurement results of the reference member FM. The control unit 2 may then calculate a difference d_diff between the maximum and minimum values ​​of the distance from the machining head 13 to the reference member FM. The difference d_diff between the maximum and minimum values ​​of the distance from the machining head 13 to the reference member FM corresponds to the difference between positions P8 and P9 described above. Therefore, the control unit 2 may calculate the radius of rotation R using the formula R = d_diff / 2.

[0161] Next, the second radius calculation operation will be described. In the second radius calculation operation, as in the first radius calculation operation, the machining unit 1 rotates the stage 16 around the rotation axis AX. Then, in the second radius calculation operation, as in the first radius calculation operation, the machining unit 1 measures the reference member FM located at position P8, and may also measure the reference member FM moved from position P8 to position P9, which is different from position P8.

[0162] The second radius calculation operation may differ from the first radius calculation operation in which positions P8 and P9 satisfy the first to third positional conditions in that positions P8 and P9 satisfy the first and second positional conditions but do not satisfy the third positional condition. In this case, as shown in Figures 21(a) and 21(b), the machining unit 1 may position the reference member FM at position P8 by rotating the stage 16 by a predetermined angle θ in one direction around the rotation axis CX (counterclockwise in the example shown in Figure 21(b)) from a reference state in which it is assumed that the reference member FM is located at position P0, which is located at the same position (same height) as the rotation axis CX in the Z-axis direction. In this state, the machining unit 1 may measure the reference member FM located at position P8. Thereafter, as shown in FIGS. 21(c) to 21(d), the machining unit 1 may place the reference member FM at position P9 by rotating the stage 16 by a predetermined angle θ from the reference state in another direction opposite to the one direction around the rotation axis CX (clockwise in the example shown in FIG. 21(d)). In this state, the machining unit 1 may measure the reference member FM located at position P9. However, as long as the machining unit 1 can measure the reference member FM located at position P8 and the reference member FM located at position P9, the method of moving the stage 16 is not limited to this method. For example, after measuring the reference member FM located at position P8, the machining unit 1 may move the reference member FM located at position P8 to position P9 by rotating the stage 16 by 2θ.

[0163] After completing the measurement of the reference member FM, the control unit 2 may calculate the radius of gyration R based on the measurement results of the reference member FM. Specifically, the control unit 2 may calculate the distance from the machining head 13 to the reference member FM based on the measurement results of the reference member FM. That is, as shown in FIGS. 22(a) and 22(b), the control unit 2 may calculate a distance d82 from the machining head 13 to the reference member FM located at position P8, and a distance d92 from the machining head 13 to the reference member FM located at position P9. In this case, as shown in FIGS. 22(a) and 22(b), the relationship sinθ=((d92-d82) / 2) / R holds between the distances d82 and d92 and the radius of gyration R. Therefore, the control unit 2 may calculate the radius of gyration R using the formula R=(d92-d82) / 2sinθ.

[0164] The machining unit 1 may perform the operation of rotating the stage 16 around the rotation axis CX so as to position the reference member FM at each of positions P8 and P9 multiple times while changing the rotation angle θ of the stage 16. In other words, when the rotation angle θ changes, the positions P8 and P9 also change. For this reason, the machining unit 1 may perform the operation of rotating the stage 16 around the rotation axis CX so as to position the reference member FM at each of positions P8 and P9 multiple times while changing the positions P8 and P9. As a result, the reference member FM may be sequentially positioned at multiple different positions P8, and may also be sequentially positioned at multiple different positions P9. In the following description, it is assumed that the stage 16 is rotated around the rotation axis CX at a rotation angle θ k (Note that k is an integer between 1 and N, and N is an integer indicating the number of times the stage 16 is rotated), the reference member FM reaches the position P8 k and P9 kIn this case, the machining unit 1 may measure the reference member FM located at position P8 and the reference member FM located at position P9 each time the stage 16 is rotated around the rotation axis CX so as to place the reference member FM at positions P8 and P9, respectively. That is, the machining unit 1 measures the reference member FM located at position P81 and the reference member FM located at position P91, measures the reference member FM located at position P82 and the reference member FM located at position P92, ..., the machining unit 1 may measure the reference member FM located at position P81 and the reference member FM located at position P91, measure the reference member FM located at position P82 and the reference member FM located at position P92, ..., the machining unit 1 may measure the reference member FM located at position P81 and the reference member FM located at position P91, ..., the machining unit 1 may ... N Reference member FM located at position P9 N Then, the control unit 2 measures the reference member FM located at position P8 k Reference member FM located at position P9 k Based on the measurement results of the reference member FM located at k That is, the control unit 2 may calculate the radius of rotation R1, the radius of rotation R2, . . . , the radius of rotation R N Then, the control unit 2 calculates the radius of rotation R1 to R2. N The average value of these may be calculated as the radius of rotation R.

[0165] In the second radius calculation operation, the distance between positions P8 and P9 in the traveling direction of the measurement light ML is shorter than in the first radius calculation operation. This reduces the effect of defocusing of the measurement light ML on the accuracy of the radius of rotation R calculated by the control unit 2. Therefore, the control unit 2 can calculate the radius of rotation R with relatively high accuracy even when the focal depth of the processing head 13 (for example, the focal depth of the objective optical system 134) is relatively shallow (small).

[0166] 16 again, after the rotation radius R is calculated, the machining unit 1 rotates the stage 16 around the rotation axis AX under the control of the control unit 2 (step S13). In this case, as shown in FIG. 23, the machining unit 1 may rotate the stage 16 around the rotation axis AX so that a mounting surface 161 on which the reference member FM is placed is perpendicular to the Z-axis direction (i.e., the direction of gravity). The machining unit 1 may rotate the stage 16 around the rotation axis AX so that the mounting surface 161 becomes a plane that intersects with the traveling direction of the measurement light ML emitted from the machining head 13 (the Z-axis direction in the example shown in FIG. 23). The machining unit 1 may rotate the stage 16 around the rotation axis AX so that a rotation axis CX perpendicular to the mounting surface 161 is parallel to the Z-axis direction.

[0167] Thereafter, the machining unit 1 measures the reference member FM (step S14). Specifically, as shown in FIGS. 24(a) and 24(b), under the control of the control unit 2, the machining unit 1 may measure the reference member FM located at position P10, and may also measure the reference member FM moved from position P10 to position P11 different from position P10. More specifically, as shown in FIG. 24(a), the machining unit 1 may first measure the reference member FM located at position P10 by irradiating the reference member FM located at position P10 with measurement light ML. Then, as shown in FIG. 24(b), the machining unit 1 may rotate (rotationally move) the stage 16 around the rotation axis CX so that the reference member FM located at position P10 moves from position P10 to position P11 different from position P10. Then, as shown in FIG. 24(b), the machining unit 1 may measure the reference member FM located at position P11 by irradiating the reference member FM located at position P11 with measurement light ML. As a result, the control unit 2 may acquire, from the processing unit 1, the detection result of the return light RL from the reference member FM generated by irradiating the reference member FM located at position P10 with the measurement light ML. Furthermore, the control unit 2 may acquire, from the processing unit 1, the detection result of the return light RL from the reference member FM generated by irradiating the reference member FM located at position P11 with the measurement light ML. The control unit 2 may calculate a movement error based on the detection result of the return light RL from the reference member FM located at position P10 and the detection result of the return light RL from the reference member FM located at position P11.

[0168] Note that the operation of measuring the reference member FM in step S14 may be the same as the operation of measuring the reference member FM in the movement error calculation operation described above. That is, in step S14, the machining unit 1 may measure the reference member FM located at position P10 and the reference member FM moved to position P11 by performing an operation similar to the operation of measuring the reference member FM in the movement error calculation operation described above. Therefore, in order to avoid redundant explanation, a detailed explanation of the operation of measuring the reference member FM in step S14 will be omitted. Unless otherwise specified, in step S14, the machining unit 1 may perform an operation similar to the operation of measuring the reference member FM in the movement error calculation operation described above.

[0169] The machining unit 1 may move the machining head 13 so that the machining head 13 follows the moving reference member FM. Specifically, the machining unit 1 may move the machining head 13 so that the moving reference member FM is included in a measurement shot area MSA that is determined based on the machining head 13. Specifically, as shown in FIG. 25(a), the machining unit 1 may irradiate the reference member FM located at position P10 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P6. Position P6 is a position that satisfies the condition that the measurement shot area MSA of the machining head 13 located at position P6 includes the reference member FM located at position P10 (i.e., position P10 is included). Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P10 using the machining head 13 (particularly, the objective optical system 134) located at position P6. Thereafter, as shown in FIG. 25(b), the machining unit 1 may rotate the stage 16 around the rotation axis CX so that the reference member FM located at position P10 moves from position P10 to position P11. Furthermore, as shown in FIG. 25(b), the machining unit 1 may move the machining head 13 located at position P6 so that the machining head 13 moves from position P6 to position P7, which is different from position P6. Position P7 is a position that satisfies the condition that the reference member FM located at position P11 is included in the measurement shot area MSA of the machining head 13 located at position P7 (i.e., position P11 is included). Thereafter, as shown in FIG. 25(b), the machining unit 1 may irradiate measurement light ML from the machining head 13 located at position P7 (particularly, the objective optical system 134) to the reference member FM located at position P11. Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P11 using the machining head 13 located at position P7 (particularly, the objective optical system 134).

[0170] 16 again, after the measurement of the reference member FM is completed, the control unit 2 may calculate a movement error that occurs in the movement of at least one of the machining head 13 and the stage 16 due to deformation of the members included in the machining unit 1, based on the radius of rotation calculated in step S12 and the measurement result of the reference member FM acquired in step S14 (step S15). That is, the control unit 2 calculates the movement error based on the measurement result of the reference member FM in step S12 and the measurement result of the reference member FM in step S14.

[0171] Specifically, the control unit 2 may calculate the position of the reference member FM (particularly, the reference position) based on the measurement results of the reference member FM. That is, the control unit 2 may generate measurement data (i.e., position information) indicating the position of the reference member FM. In particular, because the reference member FM moves, the control unit 2 may calculate the movement trajectory of the reference member FM (particularly, the movement trajectory of the reference position). That is, the control unit 2 may generate measurement data indicating the movement trajectory of the reference member FM. Note that an example of measurement data indicating the calculated position of the reference member FM (particularly, the movement trajectory) is shown using a solid line in FIG. 26. FIG. 26 shows the position (three-dimensional position) of the reference member FM measured while rotating the stage 16 around the rotation axis CX and projected onto the XY plane. Thereafter, the control unit 2 may calculate a movement error based on the calculated position of the reference member FM (i.e., the measurement data, which is position information).

[0172] Specifically, because the radius of rotation R of the reference member FM is calculated in step S12 of FIG. 16, the control unit 2 can calculate the ideal movement trajectory of the reference member FM when the stage 16 rotates around the rotation axis CX (i.e., a movement trajectory that forms a perfect circle with a radius R). On the other hand, the measurement data indicates the actual movement trajectory of the reference member FM. Here, if no movement error occurs, the calculated movement trajectory of the reference member FM coincides with the ideal movement trajectory of the reference member FM. On the other hand, if a movement error occurs, the calculated movement trajectory of the reference member FM will at least partially differ from the ideal movement trajectory of the reference member FM. Therefore, it can be said that the difference between the calculated movement trajectory of the reference member FM and the ideal movement trajectory of the reference member FM indicates a movement error. For this reason, the control unit 2 may calculate a theoretical movement trajectory of the reference member FM based on the radius of rotation R calculated in step S12 of FIG. 16. Furthermore, the control unit 2 may calculate the actual movement trajectory of the reference member FM based on the measurement result of the reference member FM acquired in step S14 of Fig. 16. Thereafter, the control unit 2 may calculate a movement error based on the difference between the ideal movement trajectory of the reference member FM and the actual movement trajectory of the reference member FM.

[0173] The movement error of the machining head 13 calculated in the deformation error calculation operation may be the same as the movement error of the machining head 13 calculated in the movement error calculation operation described above. For example, in the deformation error calculation operation, the control unit 2 calculates a movement error (for example, a movement error E X , movement error E Y and movement error E Z For example, in the deformation error calculation operation, the control unit 2 may calculate an error related to the movement axis of the machining head 13 (for example, an error related to the orthogonality (perpendicularity) between one movement axis of the machining head 13 and another movement axis). For example, in the deformation error calculation operation, the control unit 2 may calculate a movement error different from the movement errors exemplified above.

[0174] 26, the control unit 2 may calculate, as the movement error in the X-axis direction (e.g., X-axis deformation amount) occurring in the movement of the machining head 13 due to deformation of the head drive member, the absolute value of the difference between the size (e.g., diameter) Lx of the ideal movement trajectory of the reference member FM in the X-axis direction and the size (i.e., twice the radius of rotation R) of the actual movement trajectory of the reference member FM in the X-axis direction. For example, as shown in FIG. 26, the control unit 2 may calculate, as the movement error in the Y-axis direction (e.g., Y-axis deformation amount) occurring in the movement of the machining head 13 due to deformation of the head drive member, the absolute value of the difference between the size (e.g., diameter) Ly of the ideal movement trajectory of the reference member FM in the Y-axis direction and the size (i.e., twice the radius of rotation R) of the actual movement trajectory of the reference member FM in the Y-axis direction. 26, the control unit 2 may calculate the amount of deviation in the X-axis direction between the ideal movement trajectory of the reference member FM and the actual movement trajectory of the reference member FM when the rotation angle of the stage 16 is a predetermined angle θd as a movement error in the X-axis direction (e.g., pitch error) that occurs in the movement of the machining head 13 due to deformation of the head driving member. For example, as shown in Fig. 26, the control unit 2 may calculate the amount of deviation in the Y-axis direction between the ideal movement trajectory of the reference member FM and the actual movement trajectory of the reference member FM when the rotation angle of the stage 16 is a predetermined angle θd as a movement error in the Y-axis direction (e.g., pitch error) that occurs in the movement of the machining head 13 due to deformation of the head driving member.

[0175] When a movement error is calculated, the control unit 2 may control the machining unit 1 based on the movement error. Specifically, even when a movement error occurs, the control unit 2 may control the machining unit 1 so that the workpiece W is machined and the measurement object M is measured in the same manner as when no movement error occurs. For example, even when a movement error occurs, the control unit 2 may control the head drive system 14 that moves the machining head 13 so that the machining head 13 moves in the same manner as when no movement error occurs. That is, the control unit 2 may move the machining head 13 so that the movement error is canceled out. When a movement error occurring in the movement of the stage 16 is calculated by the deformation error calculation operation, for example, the control unit 2 may control the stage drive system 17 that moves the stage 16 so that the stage 16 moves in the same manner as when no movement error occurs, even when a movement error occurs. That is, the control unit 2 may move the stage 16 so that the movement error is canceled out. Since the movement error is calculated from information about the position of the reference member FM, the control unit 2 may be considered to control the movement of at least one of the processing head 13 and the stage 16 based on the information about the position of the reference member FM (i.e., to control at least one of the head drive system 14 and the stage drive system 17).The control unit 2 may be considered to control the movement of at least one of the processing head 13 and the stage 16 (i.e., to control at least one of the head drive system 14 and the stage drive system 17) based on information about the position of the reference member FM calculated from the measurement results of the reference member FM located at position P8, the measurement results of the reference member FM located at position P9, the measurement results of the reference member FM located at position P10, and the measurement results of the reference member FM located at position P11.

[0176] The control unit 2 may store movement error information relating to the calculated movement error in a storage device included in the control unit 2. The control unit 2 may store movement error information relating to the calculated movement error in a storage device arranged outside the control unit 2. In this case, the control unit 2 may control the machining unit 1 based on the movement error information stored in the storage device.

[0177] The control unit 2 may store the movement error information in a storage device together with temperature information regarding the temperature of the machining unit 1 during the measurement period in which the reference member FM was measured to calculate the movement error (in this case, the deformation error). The temperature information may include information regarding statistical values ​​of the temperature of the machining unit 1 during the measurement period (e.g., at least one of the maximum value, minimum value, average value, and median value). The control unit 2 may store, together with the temperature information, multiple pieces of movement error information corresponding to multiple environments in which the machining unit 1 has different temperatures. In this case, the control unit 2 may control the machining unit 1 based on one piece of movement error information corresponding to the temperature closest to the current temperature of the machining unit 1.

[0178] The machining system SYS may perform such a deformation error calculation operation at regular intervals. For example, the machining system SYS may perform the deformation error calculation operation every n1 (where n1 is an integer greater than or equal to 1) days. For example, the machining system SYS may perform the deformation error calculation operation every n2 (where n2 is an integer greater than or equal to 1) weeks. For example, the machining system SYS may perform the deformation error calculation operation every n3 (where n3 is an integer greater than or equal to 1) months. For example, the machining system SYS may perform the deformation error calculation operation every n4 (where n4 is an integer greater than or equal to 1) years. For example, the machining system SYS may perform the deformation error calculation operation every n5 (where n5 is an integer greater than or equal to 1) hours. Alternatively, as described above, one of the causes of movement errors is a change in temperature of the machining unit 1. In this case, the machining system SYS may perform the deformation error calculation operation when the change in temperature of the machining unit 1 exceeds a tolerable amount. That is, the machining system SYS may perform the deformation error calculation operation when it is estimated that a member included in the machining unit 1 has been deformed. Also, the above-described deformation error calculation operation may be performed after the machining system SYS is manufactured, that is, regardless of changes in the environment surrounding the machining system SYS. In this case, the manufacturing error of the machining system SYS can be calculated.

[0179] As described above, in this embodiment, the control unit 2 can calculate a movement error that occurs in the movement of at least one of the machining head 13 and the stage 16 due to deformation of a member included in the machining unit 1. Therefore, even if a member included in the machining unit 1 is deformed, the machining unit 1 can machine the workpiece W and the measurement object M under the control of the control unit 2 while reducing the influence of the movement error.

[0180] It should be noted that the members of the machining unit 1 may be deformed due to factors other than changes in the temperature of the environment in which the machining system SYS is installed. Even in this case, the machining system SYS may perform the deformation error calculation operation described above to calculate the movement error that occurs when the members of the machining unit 1 are deformed due to factors other than changes in the temperature of the environment. Examples of factors that cause deformation of the members of the machining unit 1 include at least one of aging deterioration of the machining system SYS (for example, aging deterioration of the members of the machining unit 1) and fluctuations in pressure in the machining space where the workpiece W is machined.

[0181] (3) Variations Next, a modified example of the machining system SYS will be described.

[0182] (3-1) Modified Example of Movement Error Calculation Operation In the above description, the control unit 2 calculates the movement error based on at least the measurement results of the reference member FM located at position P1 and the measurement results of the reference member FM located at position P2. That is, the machining unit 1 moves the stage 16 to move the reference member M and measures the reference member FM located at each of multiple different positions. However, the machining unit 1 may measure the reference member FM located at position P1 while not measuring the reference member FM located at position P2. That is, the machining unit 1 may not move the reference member M by moving the stage 16, and may not measure the reference member FM located at each of multiple different positions. In this case, the machining unit 1 may measure the reference member FM located at the same position while moving the machining head 13 along the traveling direction of the measurement light ML.

[0183] Specifically, as shown in Fig. 27(a), the machining unit 1 may measure the reference member FM located at position P1 using the machining head 13 located at position P21. Thereafter, as shown in Fig. 27(b), the machining unit 1 may move the machining head 13 along the Z-axis direction so that the machining head 13 located at position P21 moves from position P21 to position P22, which is different from position P21, in the Z-axis direction, which is the traveling direction of the measurement light ML. Thereafter, as shown in Fig. 27(b), the machining unit 1 may measure the reference member FM located at position P1 using the machining head 13 located at position P22.

[0184] Thereafter, the control unit 2 calculates the movement error occurring in the movement of the machining head 13 (in this case, the movement error E in the Z-axis direction occurring in the movement of the machining head 13 along the Z-axis direction) based on the measurement result of the reference member FM. ZZ ) may be calculated. Specifically, the control unit 2 may calculate the distance d21 between the machining head 13 located at position P21 and the reference member FM based on the measurement result of the reference member FM using the machining head 13 located at position P21. Furthermore, the control unit 2 may calculate the distance d22 between the machining head 13 located at position P22 and the reference member FM based on the measurement result of the reference member FM using the machining head 13 located at position P22. Here, the movement error E ZZ If no movement error E occurs, the difference between the distance d22 and the distance d21 (i.e., d22-d21) should match the target value of the movement amount of the machining head 13 in the Z-axis direction. ZZ If this occurs, the difference between the distance d22 and the distance d21 (i.e., d22-d21) does not match the target value of the movement amount of the machining head 13 in the Z-axis direction. In this case, it is estimated that the machining head 13 has moved a distance longer than the target value of the movement amount when moving from position P21 to position P22 due to a movement error. For this reason, the control unit 2 calculates the difference between the distance d22 and the distance d21, and calculates the difference between the calculated difference and the target value of the movement amount of the machining head 13 in the Z-axis direction as the movement error E. ZZ It may be calculated as:

[0185] The same operation may be performed in the deformation error calculation operation.

[0186] In the above description, when the movement error calculation operation is performed, the reference member FM is disposed at a position away from the rotation axis of the stage 16 along a direction intersecting the rotation axis. However, the reference member FM may also be disposed on the rotation axis of the stage 31. That is, the reference member FM may be disposed at the rotation center of the stage 31. In this case, the machining unit 1 may measure the reference member FM using the measurement light ML each time the stage 31 is rotated around the rotation axis by a predetermined rotation amount (i.e., by a predetermined rotation angle). The control unit 2 may calculate the rotation accuracy of the rotation axis of the stage 31 (e.g., the rotational positioning error of the rotation axis) as an example of a movement error based on the measurement results of the reference member FM. Specifically, when the rotation accuracy is calculated, a reference member FM including a polyhedron shown in FIG. 8(b) may be placed on the stage 31. In this case, the control unit 2 can calculate the orientation (e.g., the direction in which the normal extends) of each face of the reference member FM (i.e., each face of the polyhedron) based on the measurement results of the reference member FM. Therefore, the control unit 2 calculates the orientation of each surface of the reference member FM each time the stage 31 rotates by a predetermined amount. As a result, the control unit 2 can calculate the deviation between the orientation of each surface of the reference member FM and the rotation axis of the stage 31. Here, because the measurement accuracy of the measurement object using the measurement light ML is relatively high, it is estimated that the deviation between the orientation of each surface of the reference member FM and the rotation axis of the stage 31 is a deviation caused by a positioning error of the rotation axis of the stage 31. Therefore, the control unit 2 can calculate the deviation between the orientation of each surface of the reference member FM and the rotation axis of the stage 31 as a positioning error of the rotation axis of the stage 31.

[0187] (3-2) Modified Example of Calculating Deformation Error As explained with reference to FIG. 11(c), a member whose surface includes both a flat surface FMs1 and a curved surface FMs2 may be used as the reference member FM. In this case, when measuring the reference member FM to calculate the radius of gyration R in step S12 of FIG. 16, the machining unit 1 may measure the reference member FM by irradiating the flat surface FMs1 of the reference member FM with the measurement light ML, as shown in FIG. 28(a). This is because, when the distance between the machining head 13 and the reference member FM is calculated to calculate the radius of gyration R, the distance between the machining head 13 and the flat surface of the reference member FM can be calculated more accurately than the distance between the machining head 13 and the curved surface of the reference member FM. In this case, the machining unit 1 may rotate the stage 16 around the A axis so that the measurement light ML can be irradiated onto the flat surface FMs1 of the reference member FM. On the other hand, when measuring the reference member FM after calculating the radius of rotation R in step S14 of Fig. 16, the machining unit 1 may measure the reference member FM by irradiating the curved surface FMs2 of the reference member FM with the measurement light ML, as shown in Fig. 28(b). This is because, when the reference position of the reference member FM is calculated to calculate the movement error, if the shape of the curved surface FMs2 of the reference member FM (e.g., the shape of a spherical surface) is known, the reference position of the reference member FM (e.g., the position of the center of the sphere) can be calculated with high accuracy. In this case, the machining unit 1 may rotate the stage 16 around the A axis so that the measurement light ML can be irradiated onto the curved surface FMs2 of the reference member FM. In step S14 of FIG. 19, the machining unit 1 measures the reference member FM located at position P10 and the reference member FM located at position P11. Here, as shown in FIG. 29(a), if position P10 and position P11 are located at the same position along either the X-axis direction or the Y-axis direction, the machining unit 1 only needs to move the machining head 13 in either the X-axis direction or the Y-axis direction to measure the reference member FM located at position P10 and the reference member FM located at position P11. In other words, the machining unit 1 does not need to move the machining head 13 in the other of the X-axis direction or the Y-axis direction. In the example shown in FIG. 29(a), because position P10 and position P11 are located at the same position along the Y-axis direction, the machining unit 1 moves the machining head 13 in the X-axis direction to measure the reference member FM located at position P10 and the reference member FM located at position P11, but does not need to move the machining head 13 in the Y-axis direction. However, in this case, it becomes difficult to calculate the movement error occurring in the movement of the machining head 13 along either the X-axis direction or the Y-axis direction. Therefore, the machining unit 1 may measure a reference member FM located at each of at least two different positions along the X-axis direction, and may also measure a reference member FM located at each of at least two different positions along the Y-axis direction. For example, as shown in FIG. 29(b), the machining unit 1 may measure a reference member FM located at each of different positions P23 and P24 along the X-axis direction, and may also measure a reference member FM located at each of different positions P25 and P26 along the Y-axis direction. In this case, during the process of measuring the measuring member FM, the machining head 13 moves along both the X-axis direction and the Y-axis direction. As a result, the control unit 2 can calculate the movement error occurring in the movement of the machining head 13 along each of the X-axis direction and the Y-axis direction.

[0188] 19, the control unit 2 may calculate the three-dimensional position of the reference member FM in addition to the distance between the machining head 13 and the reference member FM. Specifically, the control unit 2 may calculate the three-dimensional position of the reference member FM located at position P8 and the three-dimensional position of the reference member FM located at position P9. In this case, the control unit 2 calculates the movement error in the Z-axis direction (for example, the above-mentioned movement error E) that occurs in the movement of the machining head 13 along at least one of the X-axis direction and the Y-axis direction, based on the measurement result of the reference member FM in step S14 of FIG. 16 and the three-dimensional position of the reference member FM calculated in step S12 of FIG. ZX and movement error E ZY) may be calculated. Specifically, the control unit 2 may calculate the ideal distance d0 between the machining head 13 and the reference member FM at the time when the reference member FM is measured in step S14 of FIG. 16 based on the three-dimensional position of the reference member FM calculated in step S12 of FIG. 16 and the amount of rotation of the stage 16 in step S13 of FIG. 16. Furthermore, the control unit 2 may calculate the actual distance between the machining head 13 and the reference member FM at the time when the reference member FM is measured in step S14 of FIG. 16 based on the measurement results of the reference member FM in step S14 of FIG. 16. For example, the control unit 2 may calculate a distance d330 between the machining head 13 and the reference member FM located at position P10, and a distance d331 between the machining head 13 and the reference member FM located at position P11. Here, if no movement error occurs in the Z-axis direction, the distances d330 and d331 should each match the ideal distance d0, as shown in FIG. 30(a). On the other hand, if a movement error occurs in the Z-axis direction, at least one of the distances d330 and d331 will not match the ideal distance d0. This is because, if a movement error occurs in the Z-axis direction, the machining head 13 will move not only in at least one of the X-axis direction and the Y-axis direction but also along the Z-axis direction as it moves from position P6 to position P7. For this reason, the control unit 2 may calculate the difference between the ideal distance d0 and at least one of the distances d330 and d331 calculated from the measurement results as the movement error in the Z-axis direction. Alternatively, the control unit 2 may calculate the difference between the distances d330 and d331 calculated from the measurement results as the movement error in the Z-axis direction.

[0189] When calculating the rotation radius R in step S12 of FIG. 19, the machining unit 1 rotates the stage 16 around the rotation axis AX so that the mounting surface 161 on which the reference member FM is placed is parallel to the Z-axis direction (see FIGS. 17(a) and 17(b)). However, in step S12, the machining unit 1 may measure the reference member FM in a state in which the mounting surface 161 on which the reference member FM is placed is perpendicular to the Z-axis direction. Specifically, as shown in FIG. 31(a), the machining unit 1 may irradiate measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P15 to the reference member FM located at position P10 (or a position different from position P10, the same applies hereinafter in this paragraph). Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P10 using the machining head 13 located at position P15. 31(b), the machining unit 1 may irradiate measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P15 onto the reference member FM located at position P11 (or a position different from position P11, the same applies hereinafter in this paragraph). Furthermore, the machining unit 1 may receive return light RL from the reference member FM located at position P11 using the machining head 13 located at position P15. Therefore, position P15 is a position that satisfies the condition that the measurement shot area MSA of the machining head 13 located at position P15 includes both the reference member FM located at position P10 and the reference member FM located at position P11 (i.e., includes both positions P10 and P11). Furthermore, if necessary, the machining unit 1 may further measure the reference member FM that has moved from position P11 to a position different from positions P10 and P11. The machining unit 1 may measure the reference member FM each time the stage 16 rotates a predetermined angle around the rotation axis CX. Thereafter, the control unit 2 may calculate the position (particularly, the movement trajectory) of the reference member FM based on the measurement results of the reference member FM. Here, since the machining head 13 is not moving, the calculated movement trajectory is not affected by movement errors that occur in the movement of the machining head 13. Therefore, the calculated movement trajectory is the actual movement trajectory of the reference member FM.Therefore, the control unit 2 may calculate the radius of the calculated movement trajectory (for example, the radius of the movement trajectory projected onto the XY plane) as the radius of rotation R of the reference member FM. In this case, since it is not necessary to rotate the stage 16 around the A axis to calculate the radius of rotation R, the accuracy of the radius of rotation R is not affected by movement errors that occur in the movement of the stage 16 around the A axis. Therefore, the control unit 2 can calculate the radius of rotation R with relatively high accuracy.

[0190] 16, the machining unit 1 may measure at least the reference member FM located at position P10 and the reference member FM located at position P11. In this case, as shown in FIG. 32(a), the machining unit 1 may irradiate the reference member FM located at position P10 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P13, which is different from position P15. Position P13 is a position that satisfies the condition that the reference member FM located at position P10 is included in the measurement shot area MSA of the machining head 13 located at position P13 (i.e., position P10 is included). Furthermore, the machining unit 1 may use the machining head 13 located at position P13 to receive return light RL from the reference member FM located at position P10. Then, as shown in FIG. 32(b), the machining unit 1 may rotate the stage 16 around the rotation axis CX so that the reference member FM located at position P10 moves from position P10 to position P11. Furthermore, as shown in FIG. 32(b), the machining unit 1 may move the machining head 13 so that the machining head 13 located at position P13 moves from position P13 to position P14, which is different from position P13. Position P14 is a position that satisfies the condition that the reference member FM located at position P11 is included in the measurement shot area MSA of the machining head 13 located at position P14 (i.e., position P11 is included). Thereafter, as shown in FIG. 32(b), the machining unit 1 may irradiate measurement light ML from the machining head 13 located at position P14 (particularly, the objective optical system 134) to the reference member FM located at position P11. Furthermore, the machining unit 1 may use the machining head 13 located at position P14 to receive return light RL from the reference member FM located at position P11.

[0191] Alternatively, as shown in FIG. 33(a), the machining unit 1 may irradiate the reference member FM located at position P10 with measurement light ML from the machining head 13 (particularly, the objective optical system 134) located at position P16, which is the same position P15 where the machining head 13 was located to calculate the radius of rotation R. Furthermore, the machining unit 1 may use the machining head 13 located at position P16 to receive return light RL from the reference member FM located at position P10. Thereafter, as shown in FIG. 33(b), the machining unit 1 may rotate the stage 16 around the rotation axis CX so that the reference member FM located at position P10 moves from position P10 to position P11. Furthermore, as shown in FIG. 33(b), the machining unit 1 may move the machining head 13 located at position P16 so that the machining head 13 located at position P16 moves from position P16 to position P17, which is different from position P16. Position P17 is a position that satisfies the condition that the reference member FM located at position P11 is included in the measurement shot area MSA of the machining head 13 located at position P17 (i.e., position P11 is included). Thereafter, as shown in FIG. 33(b), the machining unit 1 may irradiate measurement light ML from the machining head 13 (particularly the objective optical system 134) located at position P17 onto the reference member FM located at position P11. Furthermore, the machining unit 1 may use the machining head 13 located at position P17 to receive return light RL from the reference member FM located at position P11.

[0192] The control unit 2 may calculate a movement error of the stage 16 based on the radius of rotation R of the reference member FM calculated in the first radius calculation operation and the movement amount of the reference member FM in the second radius calculation operation. Specifically, when the radius of rotation R of the reference member FM is calculated in the first radius calculation operation, the control unit 2 can calculate, from the radius of rotation R, target values ​​of the movement amount (e.g., d92-d82 shown in FIG. 25 ) of the reference member FM when the stage 16 is rotated clockwise and counterclockwise by a desired rotation angle (e.g., 180 degrees, a rotation angle smaller than 180 degrees, or a rotation angle larger than 180 degrees) about the rotation axis CX from the reference state in the second radius calculation operation. Meanwhile, the control unit 2 can calculate the actual movement amount of the reference member FM when the stage 16 is rotated by the desired rotation angle about the rotation axis CX based on the measurement result of the reference member FM in the second radius calculation operation. When there is no movement error of the stage 16, the target value of the movement amount of the measuring member FM and the actual movement amount of the measuring member FM match. On the other hand, when there is a movement error of the stage 16, the target value of the movement amount of the measuring member FM and the actual movement amount of the measuring member FM do not match. For this reason, the control unit 2 may calculate the movement error of the stage 16 by comparing the target value of the movement amount of the measuring member FM with the actual movement amount of the measuring member FM. Note that this is not limited to when the stage 16 is rotated clockwise and counterclockwise by a desired rotation angle from the reference state, but the same can be said when the stage 16 is rotated in any direction by a desired rotation angle.

[0193] In the above description, in FIG. 16, the machining system SYS calculates the radius of rotation R of the reference member FM (step S12), and then measures the reference member FM while rotating the stage 16 about the rotation axis CX (step S14). However, the machining system SYS may calculate the radius of rotation R of the reference member FM (step S12) after measuring the reference member FM while rotating the stage 16 about the rotation axis CX (step S14). In other words, the machining system SYS may change the order in which the operations of steps S12 and S14 are performed. Even in this case, the control unit 2 can calculate the movement error. The machining system SYS may arbitrarily change the order of the operations shown in FIG. 16 as long as it is possible to calculate the movement error.

[0194] In the above description, the operation of step S12 in FIG. 16 (i.e., at least one of the first and second radius calculation operations for calculating the radius of rotation R) is performed to calculate a movement error. However, the processing system SYS may perform the operation of step S12 in FIG. 16 for a purpose other than calculating a movement error. The processing system SYS may perform the operation of step S12 in FIG. 16 regardless of the calculation of a movement error. For example, the processing system SYS may perform the operation of step S12 in FIG. 16 to calculate the degree of at least one of thermal expansion and thermal contraction of the mounting surface 161 of the stage 16. Specifically, the processing system SYS may calculate the radius of rotation R in advance as a reference radius of rotation R0 by at least one of the first and second radius calculation operations under a condition in which the processing system SYS is placed in a reference environment in advance. Thereafter, the processing system SYS may calculate the degree of at least one of thermal expansion and thermal contraction of the mounting surface 161 of the stage 16 from the rotation radius R obtained by performing at least one of the first radius calculation operation and the second radius calculation operation again and the reference rotation radius R0.

[0195] (3-3) Other Modifications In the above description, the machining system SYS capable of machining the workpiece W performs the movement error calculation operation. However, a measurement system SYSa capable of measuring a measurement object M such as the workpiece W may perform at least one of the above-described optical calibration operation, movement error calculation operation, and deformation error calculation operation. An example of the configuration of the measurement system SYSa is shown in FIG. 34. As shown in FIG. 34, the measurement system SYSa may differ from the machining system SYS in that it includes a measurement unit 1a instead of the machining unit 1. The measurement unit 1a may differ from the machining unit 1 in that it includes a measurement light source 11a instead of the machining light source 11 and a measurement head 13a instead of the machining head 13. The measurement light source 11a is capable of generating measurement light. The measurement head 13a may differ from the machining head 13 in that it includes a measurement optical system 131a for irradiating the measurement object M with the measurement light generated by the measurement light source 11a instead of the machining optical system 131. Other features of the measurement system SYSa may be the same as those of the machining system SYS. The optical calibration operation performed by the measurement system SYSa may be an operation for aligning a target irradiation position onto which the measurement head 13a irradiates measurement light (i.e., measurement light from the measurement optical system 131a) and a target irradiation position MA onto which the measurement head 13a irradiates measurement light ML (i.e., measurement light ML from the measurement optical system 132). The movement error calculation operation performed by the measurement system SYSa may be an operation for calculating a movement error occurring in the movement of at least one of the measurement head 13a and the stage 16. The deformation error calculation operation performed by the measurement system SYSa may be an operation for calculating a movement error occurring in the movement of at least one of the measurement head 13a and the stage 16 due to deformation of a member included in the measurement unit 1a.

[0196] The measurement optical system 132 may be detachably attached to the processing head 13. In this case, when the measurement light ML is irradiated onto the reference member FM, the measurement optical system 132 may be attached to the processing head 13. On the other hand, when the processing head 13 processes the workpiece W, the measurement optical system 132 may be detached from the processing head 13.

[0197] In the above description, the processing system SYS processes the workpiece W by irradiating the workpiece W with processing light EL. In other words, the processing system SYS processes the workpiece W by irradiating the workpiece W with an energy beam in the form of light. However, the processing system SYS may irradiate the workpiece W with any energy beam other than light to process the workpiece W. Examples of any energy beam include at least one of a charged particle beam and an electromagnetic wave. Examples of a charged particle beam include at least one of an electron beam and an ion beam. Furthermore, in the above description, the processing system SYS processes the workpiece W by irradiating the workpiece W with measurement light ML. However, the processing system SYS may irradiate the workpiece W with any energy beam other than light to measure the workpiece W.

[0198] As shown in FIG. 35 , the head drive system 14 may include a robot arm. That is, the head drive system 14 may move the processing head 13 using a robot arm. The robot arm may be a manipulator with three or more degrees of freedom. The robot arm may function as a robot having a so-called vertical multi-joint structure. The robot arm may function as a polar coordinate robot having a horizontal multi-joint structure. The robot arm may function as a cylindrical coordinate robot. The robot arm may function as a Cartesian coordinate robot. The robot arm may function as a parallel link robot. The processing head 13 may be attached to the tip of the robot arm. That is, the processing head 13 may be attached to the robot arm as an end effector. Although not shown, the stage drive system 17 may also include a robot arm. That is, the stage drive system 17 may move the stage 16 using a robot arm.

[0199] (4) Supplementary notes The following additional notes are provided regarding the above-described embodiment. [Appendix 1] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a processing device capable of irradiating a processing beam for processing the workpiece onto the workpiece via an objective optical system; a light detection device capable of irradiating the reference member with a measurement beam via the objective optical system and receiving, via the objective optical system, at least a portion of light from the reference member generated by the irradiation of the measurement beam; a processing head including the objective optical system; a rotation device that rotates the placement device; Calculation unit and Equipped with the light detection device obtains a first detection result by irradiating the measurement beam onto the reference member located at a first position, and obtains a second detection result by irradiating the measurement beam onto the reference member that has been moved from the first position to a second position different from the first position using the rotation device; The calculation unit calculates a movement error occurring in movement of at least one of the placement device and the processing head based on position information of the reference member obtained using the first detection result and position information of the reference member obtained using the second detection result. Processing system. [Appendix 2] The light detection device irradiates the measurement beam onto the reference member located at the first position via the objective optical system located at a third position, and irradiates the measurement beam onto the reference member located at the second position via the objective optical system located at the third position. 10. The processing system of claim 1. [Appendix 3] the light detection device is capable of deflecting the measurement beam so that the measurement beam scans a measurement region; The first and second positions are located within the measurement region that can be scanned with the measurement beam from the objective optical system located at the third position. 10. The processing system of claim 2. [Appendix 4] The movement error calculated by the calculation unit includes a movement error that occurs when the rotation device moves the placement device. 4. The processing system of any one of claims 1 to 3. [Appendix 5] a moving device that moves the processing head along a movement axis that intersects with the optical axis of the objective optical system, the light detection device irradiates the measurement beam onto the reference member located at the first position via the objective optical system located at a fourth position, and receives light from the reference member; thereafter, the rotation device rotates the mounting device so that the reference member moves from the first position to the second position, and the movement device moves the objective optical system so that the objective optical system moves from the fourth position to a fifth position different from the fourth position; Thereafter, the light detection device irradiates the measurement beam onto the reference member located at the second position via the objective optical system located at the fifth position, and receives light from the reference member. 5. The processing system of any one of claims 1 to 4. [Appendix 6] Further, a moving device is provided to move the processing head along a moving axis, the light detection device irradiates the measurement beam onto the reference member located at an eighth position and the reference member located at a ninth position via the objective optical system, and then irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a sixth position, and receives light from the reference members; Thereafter, the rotation device rotates the mounting device so that the reference member moves from the tenth position to an eleventh position different from the tenth position, and the movement device moves the objective optical system so that the objective optical system moves from the sixth position to a seventh position different from the sixth position; Thereafter, the photodetector irradiates the measurement beam onto the reference member located at the eleventh position via the objective optical system located at the seventh position, and receives light from the reference member. 6. The processing system of any one of claims 1 to 5. [Appendix 7] a control unit that controls the processing device and the light detection device, The control unit adjusts the relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam. 7. The processing system of any one of claims 1 to 6. [Appendix 8] a control unit that controls the processing device and the light detection device, The control unit controls the light detection device to irradiate the measurement beam onto the reference member located at the first position and the reference member located at the second position, based on a relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam. 7. The processing system of any one of claims 1 to 6. [Appendix 9] a control unit that controls the processing device and the light detection device, The control unit adjusts a relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam, and then controls the light detection device to irradiate the reference member located at the first position and the reference member located at the second position with the measurement beam. 7. The processing system of any one of claims 1 to 6. [Appendix 10] Further, a moving device is provided to move the processing head along a moving axis, The movement error calculated by the calculation unit includes at least one of a movement error occurring when the rotation device moves the mounting device and a movement error occurring when the movement device moves the mounting device. 10. The processing system of any one of claims 1 to 9. [Appendix 11] the light detection device is capable of irradiating the measurement beam onto the workpiece via the objective optical system, and is capable of receiving at least a portion of light from the workpiece generated by irradiation of the measurement beam via the objective optical system; A processing position to which the processing beam is irradiated is controlled based on at least one of the position and the shape of at least a part of the workpiece obtained using a detection result of the light detection device by irradiating the measurement beam onto the workpiece. 11. The processing system of any one of claims 1 to 10. [Appendix 12] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a rotation device that can rotate the mounting device around a first axis and around a second axis that intersects with the first axis; a moving device that moves a processing head including at least the objective optical system along a moving axis; Calculation unit and Equipped with the rotation device rotates the mounting device around the first axis to move the reference member from an eighth position to a ninth position, and rotates the mounting device around the second axis to move the reference member from a tenth position to an eleventh position; the light detection device obtains an eighth detection result by irradiating the reference member located at the eighth position with the measurement beam via the objective optical system located at a twelfth position, obtains a ninth detection result by irradiating the reference member moved to the ninth position with the measurement beam via the objective optical system located at the twelfth position, obtains a tenth detection result by irradiating the reference member located at the tenth position with the measurement beam via the objective optical system located at a thirteenth position, and obtains an eleventh detection result by irradiating the reference member located at the eleventh position with the measurement beam via the objective optical system located at the thirteenth position or a fourteenth position different from the thirteenth position, The calculation unit calculates a movement error occurring in movement of at least one of the placement device and the processing head based on position information of the reference member obtained using the eighth detection result, position information of the reference member obtained using the ninth detection result, position information of the reference member obtained using the tenth detection result, and position information of the reference member obtained using the eleventh detection result. Processing system. [Appendix 13] the mounting device includes a mounting surface on which the reference member is placed, the rotation device is capable of making the placement surface parallel to the direction of gravity and perpendicular to the direction of gravity by rotating the placement device around the first axis, the rotation device is capable of moving the reference member from the eighth position to the ninth position by rotating the placement device around the second axis when the placement surface is parallel to the direction of gravity; The rotation device is capable of moving the reference member from the tenth position to the eleventh position by rotating the placement device around the second axis when the placement surface is perpendicular to the direction of gravity. 13. The processing system of claim 12. [Appendix 14] the mounting device includes a mounting surface on which the reference member is placed, the rotation device rotates the mounting device around the first axis along the mounting surface so that the mounting surface becomes a surface along a traveling direction of the measurement beam; After the placement surface becomes a surface along the traveling direction of the measurement beam, (i) the photodetector irradiates the measurement beam onto the reference member located at the eighth position via the objective optical system located at the twelfth position, and then (ii) the rotation device rotates the placement device around the second axis intersecting both the placement surface and the first axis so that the reference member moves from the eighth position to the ninth position, and then (iii) the photodetector irradiates the measurement beam onto the reference member located at the ninth position via the objective optical system located at the twelfth position. 14. The processing system of claim 12 or 13. [Appendix 15] The eighth position and the ninth position are aligned along the traveling direction of the measurement beam. 15. The processing system of any one of claims 12 to 14. [Appendix 16] The eighth position and the ninth position are located at the same position in a direction along a plane intersecting the traveling direction of the measurement beam, and are located at different positions in a direction along the traveling direction of the measurement beam. 16. The processing system of any one of claims 12 to 15. [Appendix 17] The rotation device rotates the placement device around the second axis so that the eighth position and the ninth position are located at two positions where a circle centered on the second axis intersects with a line passing through the center of the circle. 17. The processing system of any one of claims 12 to 16. [Appendix 18] The rotation device rotates the mounting device 180 degrees around the second axis to move the reference member from the eighth position to the ninth position. 18. The processing system of any one of claims 12 to 17. [Appendix 19] the rotation device rotates the placement device multiple times while changing the rotation angle so that the reference member moves from the eighth position to the ninth position; The photodetector irradiates the measurement beam onto the reference member positioned at the eighth position and the reference member positioned at the ninth position every time the rotation device rotates the mounting device. 19. The processing system of any one of clauses 12 to 18. [Appendix 20] The reference member includes both a curved surface and a flat surface, the light detection device irradiates the measurement beam onto the flat surface of the reference member located at the eighth position and the flat surface of the reference member located at the ninth position; The photodetector irradiates the measurement beam onto the curved surface of the reference member located at the tenth position and the curved surface of the reference member located at the eleventh position. 20. The processing system of any one of claims 12 to 19. [Appendix 21] A processing beam for processing the workpiece can be irradiated onto the workpiece via the objective optical system, and the measurement beam can be irradiated onto the reference member. 21. The processing system of any one of clauses 12 to 20. [Appendix 22] The moving device moves the objective optical system of the processing head so that the objective optical system follows the reference member that is moved by the rotation device rotating the placement device. 22. The processing system of any one of claims 12 to 21. [Appendix 23] a control unit that controls the moving device based on position information of the reference member obtained using each of the eighth detection result and the ninth detection result, and position information of the reference member obtained using each of the tenth detection result and the eleventh detection result. 23. The processing system of any one of clauses 12 to 22. [Appendix 24] The calculation unit (i) calculates an ideal movement trajectory of the reference member that moves when the rotation device rotates the mounting device, based on position information of the reference member obtained using each of the eighth detection result and the ninth detection result; and (ii) calculates an actual measurement result of the movement trajectory of the reference member, based on measurement results of the reference member obtained using each of the tenth detection result and the eleventh detection result. The moving device is controlled based on the difference between the ideal movement locus of the reference member and the actual measurement result of the movement locus of the reference member. 24. The processing system of claim 23. [Appendix 25] The reference member includes at least one of a curved surface and a flat surface. 25. The processing system of any one of claims 1 to 24. [Appendix 26] The rotation device is controlled based on position information of the reference member obtained using the measurement beam. 26. The processing system of any one of claims 1 to 25. [Appendix 27] a moving device that moves the objective optical system along a movement axis; The moving device is controlled based on position information of the reference member obtained using the measurement beam. 5. The processing system of any one of claims 1 to 4. [Appendix 28] a control unit that controls the moving device based on position information of the reference member obtained using the measurement beam 25. The processing system of any one of clauses 12 to 24. [Appendix 29] the moving device moves the processing head along a first movement axis, a second movement axis intersecting the first movement axis, and a third movement axis intersecting the first and second movement axes, the calculation unit calculates a movement error occurring in movement of the machining head along at least one of the first to third movement axes; The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error. 25. The processing system of any one of clauses 12 to 24. [Appendix 30] the rotation device is capable of rotating the placement device around a first axis; the calculation unit calculates a movement error occurring in movement of the mounting device along a rotation direction around the first axis; The rotation device moves the placement device based on the movement error calculated by the calculation unit so as to cancel out the movement error. 14. The processing system of any one of claims 1 to 13. [Appendix 31] Further provided is a moving device that moves the processing head along a first movement axis extending in a vertical direction, The calculation unit calculates a movement error that occurs in movement of the machining head along the first movement axis, The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error. 31. The processing system of any one of claims 1 to 13 and 30. [Appendix 32] a moving device that moves the processing head along a second movement axis that extends horizontally and a third movement axis that extends horizontally and intersects with the second movement axis; the calculation unit calculates a movement error occurring in movement of the machining head along at least one of the second and third movement axes; The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error. 32. The processing system of any one of appendixes 1 to 13 and 30 to 31. [Appendix 33] the light detection device is capable of irradiating the measurement beam onto the workpiece through the objective optical system during at least one of a first period before processing of the workpiece is started, a second period during which the workpiece is being processed, and a third period after processing of the workpiece W is completed, and is capable of receiving at least a portion of the light from the workpiece W generated by irradiation with the measurement beam through the objective optical system; The calculation unit calculates at least one of the position and the shape of at least a part of the workpiece based on the detection result of the light detection device when the measurement beam is irradiated onto the workpiece. 33. The processing system of any one of claims 1 to 32. [Appendix 34] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a processing device for processing the workpiece; a light detection device capable of irradiating the reference member with a measurement beam via an objective optical system and receiving at least a portion of light from the reference member generated by the irradiation of the measurement beam; a processing head including at least the objective optical system and a part of the processing device; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at a first position, and irradiates the measurement beam onto the reference member moved by the drive device from the first position to a second position different from the first position. Processing system. [Appendix 35] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at an eighth position via the objective optical system located at a twelfth position, and irradiates the measurement beam onto the reference member moved to a ninth position via the objective optical system located at the twelfth position. Processing system. [Appendix 36] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at a 10th position via the objective optical system located at a 15th position, and irradiates the measurement beam onto the reference member moved to an 11th position via the objective optical system located at the 15th position, and further irradiates the measurement beam onto the reference member located at a 10th position via the objective optical system located at a 13th position, and irradiates the measurement beam onto the reference member moved to an 11th position via the objective optical system located at a 14th position. Processing system. [Appendix 37] a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a sixteenth position, irradiates the measurement beam onto the reference member moved to an eleventh position via the objective optical system located at the sixteenth position, and further irradiates the measurement beam onto the reference member moved to the eleventh position via the objective optical system located at a seventeenth position. Processing system. [Appendix 38] A movement error calculation system for calculating a movement error occurring in movement of at least one of a mounting device on which a workpiece is rotatably mounted and a machining head of a machine tool that moves the mounting device and a machining head and processes the workpiece using the machining head, comprising: a light detection device that irradiates a measurement beam onto a reference member placed on the mounting device via an objective optical system attached to the processing head, and receives at least a portion of light from the reference member generated by the irradiation of the measurement beam via the objective optical system; Calculation unit and Equipped with the light detection device acquires a first detection result by irradiating the measurement beam onto the reference member located at a first position, and acquires a second detection result by irradiating the measurement beam onto the reference member that has moved from the first position to a second position different from the first position due to rotation of the reference member placed on the mounting device; The calculation unit calculates a movement error occurring in movement of at least one of the placement device and the processing head based on position information of the reference member obtained using the first detection result and position information of the reference member obtained using the second detection result. Movement error calculation system. [Appendix 39] The processing head is capable of irradiating the workpiece with a processing beam for processing the workpiece via the objective optical system. 39. The movement error calculation system of claim 38. [Appendix 40] The machine tool includes a rotation device that rotates the placement device to rotate at least one of the workpiece and the reference member. 40. The movement error calculation system according to claim 38 or 39. [Appendix 41] the machine tool includes a moving device that moves the machining head so as to follow the reference member that rotates; The light detection device obtains the first detection result by irradiating the reference member, which is located at the first position, with the measurement beam via the objective optical system of the processing head, which is located at a third position, and follows the reference member, which is located at the second position, and obtains the second detection result by irradiating the reference member, which is located at a fourth position, with the measurement beam via the objective optical system of the processing head, which is located at a fourth position, and follows the reference member, which is located at the second position. 41. A movement error calculation system according to any one of appendices 38 to 40. [Appendix 42] The light detection device irradiates the measurement beam onto at least one of the workpiece and the reference member along a first optical path, and receives, via the objective optical system, light that travels along the first optical path among light generated by the irradiation of the measurement beam. 42. A movement error calculation system according to any one of appendices 38 to 41. [Appendix 43] A movement error calculation method for calculating a movement error occurring in movement of at least one of a mounting device on which a workpiece is rotatably mounted and a machining head of a machine tool that machines the workpiece using the machining head while moving the mounting device and / or the machining head, comprising: irradiating a measurement beam onto a reference member placed on the mounting device and located at a first position via an objective optical system attached to the processing head; receiving, via the objective optical system, at least a portion of light from the reference member located at the first position, which is generated by irradiation with the measurement beam; After rotating the reference member on the mounting device, irradiating the measurement beam onto the reference member located at a second position different from the first position via the objective optical system; receiving at least a portion of light from the reference member located at the second position, the light being generated by irradiation with the measurement beam; calculating the movement error based on a detection result regarding the reference member located at the first position and a detection result regarding the reference member located at the second position; A movement error calculation method including: [Appendix 44] a placement device for placing a workpiece; a machining head that processes the workpiece placed on the placement device; a rotation device that rotates and moves the placement device; a light detection device that irradiates a measurement beam onto a reference member placed on the mounting device via an objective optical system attached to the processing head, and receives at least a portion of light from the reference member generated by the irradiation of the measurement beam via the objective optical system; a control unit that controls the rotation device and the light detection device so that the measurement beam is irradiated onto the reference member located at a first position, and the measurement beam is irradiated onto the reference member that has been rotationally moved from the first position to a second position different from the first position by the rotation device; Equipped with The workpiece is machined based on a detection result regarding the reference member located at the first position and a detection result regarding the reference member located at the second position. Processing system. [Appendix 45] When the measurement beam is irradiated onto the reference member, the light detection device is attached to the processing head, When the processing head processes the workpiece, the light detection device is detached from the processing head. 45. The processing system of claim 44. [Appendix 46] a placement device for placing a workpiece; a measuring head that measures the workpiece placed on the placement device; a rotation device that rotates and moves the placement device; a light detection device that irradiates a measurement beam onto a reference member placed on the mounting device via an objective optical system attached to the measurement head, and receives at least a portion of light from the reference member generated by the irradiation of the measurement beam via the objective optical system; a control unit that controls the rotation device and the light detection device so that the measurement beam is irradiated onto the reference member located at a first position, and the measurement beam is irradiated onto the reference member that has been rotationally moved from the first position to a second position different from the first position by the rotation device; Equipped with measuring the workpiece based on a detection result regarding the reference member located at the first position and a detection result regarding the reference member located at the second position; Measurement system. [Appendix 47] A movement error calculation system for a measuring device that measures a workpiece using a measurement head while moving at least one of a mounting device on which a workpiece is rotatably mounted and a measurement head, the system calculating a movement error that occurs in movement of at least one of the mounting device and the measurement head, a light detection device that irradiates a measurement beam onto a reference member placed on the mounting device via an objective optical system attached to the measurement head, and receives at least a portion of light from the reference member generated by the irradiation of the measurement beam via the objective optical system; Calculation unit and Equipped with the light detection device obtains a first detection result by irradiating the measurement beam onto the reference member located at a first position, and obtains a second detection result by irradiating the measurement beam onto the reference member that has moved from the first position to a second position different from the first position due to rotation of the reference member; The calculation unit calculates a movement error occurring in movement of at least one of the mounting device and the measuring head based on position information of the reference member obtained using the first detection result and position information of the reference member obtained using the second detection result. Movement error calculation system.

[0200] At least some of the constituent elements of each of the above-described embodiments can be appropriately combined with at least some of the other constituent elements of each of the above-described embodiments. Some of the constituent elements of each of the above-described embodiments may not be used. Furthermore, to the extent permitted by law, the disclosures of all publications and U.S. patents cited in each of the above-described embodiments are incorporated herein by reference.

[0201] The present invention is not limited to the above-described embodiments, but can be modified as appropriate within the scope of the claims and the gist or idea of ​​the invention as can be read from the entire specification, and machining systems, movement error calculation systems, movement error calculation methods, and measurement systems that involve such modifications are also included in the technical scope of the present invention. [Explanation of symbols]

[0202] SYS Machining System 1 Processing unit 13 Processing head 131 Processing optical system 132 Measurement Optical System 1323, 1326 detectors 133 Synthetic optical system 134 Objective Optical System 1342 fθ lens 14 Head drive system 16 stages 17 Stage drive system 2. Control Unit 3. Housing 4 Measuring components 41 Beam Profiler double work M Measurement target FM reference material EL processing light ML measurement light PA, MA target irradiation position PSA processing shot area MSA measurement shot area

Claims

1. A mounting device capable of mounting a workpiece and a reference member different from the workpiece; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a drive unit for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at an eighth position via the objective optical system located at a twelfth position, and irradiates the measurement beam onto the reference member moved to a ninth position via the objective optical system located at the twelfth position. Processing system.

2. A processing device capable of irradiating a processing beam for processing the workpiece onto the workpiece via the objective optical system; a processing head including the objective optical system; a rotation device that rotates the placement device; Calculation unit and Equipped with the light detection device is capable of receiving, via the objective optical system, at least a portion of the light from the reference member generated by irradiation with the measurement beam; the light detection device obtains a first detection result by irradiating the measurement beam onto the reference member located at a first position, and obtains a second detection result by irradiating the measurement beam onto the reference member that has been moved from the first position to a second position different from the first position using the rotation device; The calculation unit calculates a movement error occurring in movement of at least one of the placement device and the processing head based on position information of the reference member obtained using the first detection result and position information of the reference member obtained using the second detection result. The processing system of claim 1 .

3. The light detection device irradiates the measurement beam onto the reference member located at the first position via the objective optical system located at a third position, and irradiates the measurement beam onto the reference member located at the second position via the objective optical system located at the third position. The processing system according to claim 2 .

4. the light detection device is capable of deflecting the measurement beam so that the measurement beam scans a measurement region; The first and second positions are located within the measurement region that can be scanned with the measurement beam from the objective optical system located at the third position. The processing system according to claim 3 .

5. The movement error calculated by the calculation unit includes a movement error that occurs when the rotation device moves the placement device. The processing system according to any one of claims 2 to 4.

6. a moving device that moves the processing head along a movement axis that intersects with the optical axis of the objective optical system, the light detection device irradiates the measurement beam onto the reference member located at the first position via the objective optical system located at a fourth position and receives light from the reference member; thereafter, the rotation device rotates the mounting device so that the reference member moves from the first position to the second position, and the movement device moves the objective optical system so that the objective optical system moves from the fourth position to a fifth position different from the fourth position; Thereafter, the light detection device irradiates the measurement beam onto the reference member located at the second position via the objective optical system located at the fifth position, and receives light from the reference member. The processing system according to any one of claims 2 to 5.

7. Further, a moving device is provided to move the processing head along a moving axis, the light detection device irradiates the measurement beam onto the reference member located at the eighth position and the reference member located at the ninth position via the objective optical system, and then irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a sixth position, and receives light from the reference members; Thereafter, the rotation device rotates the mounting device so that the reference member moves from the tenth position to an eleventh position different from the tenth position, and the movement device moves the objective optical system so that the objective optical system moves from the sixth position to a seventh position different from the sixth position; Thereafter, the light detection device irradiates the measurement beam onto the reference member located at the eleventh position via the objective optical system located at the seventh position, and receives light from the reference member. The processing system according to any one of claims 2 to 6.

8. a control unit that controls the processing device and the light detection device, The control unit adjusts the relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam. The processing system according to any one of claims 2 to 7.

9. a control unit that controls the processing device and the light detection device, The control unit controls the light detection device to irradiate the measurement beam onto the reference member located at the first position and the reference member located at the second position, based on a relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam. The processing system according to any one of claims 2 to 7.

10. a control unit that controls the processing device and the light detection device, The control unit adjusts a relationship between a processing position to be irradiated with the processing beam and a measurement position to be irradiated with the measurement beam, and then controls the light detection device to irradiate the reference member located at the first position and the reference member located at the second position with the measurement beam. The processing system according to any one of claims 2 to 7.

11. Further, a moving device is provided to move the processing head along a moving axis, The movement error calculated by the calculation unit includes at least one of a movement error occurring when the rotation device moves the mounting device and a movement error occurring when the movement device moves the mounting device. The processing system according to any one of claims 2 to 10.

12. the light detection device is capable of irradiating the measurement beam onto the workpiece via the objective optical system, and is capable of receiving at least a portion of light from the workpiece generated by irradiation of the measurement beam via the objective optical system; A processing position to which the processing beam is irradiated is controlled based on at least one of the position and the shape of at least a part of the workpiece obtained using a detection result of the light detection device by irradiating the measurement beam onto the workpiece. The processing system according to any one of claims 2 to 11.

13. a rotation device that can rotate the mounting device around a first axis and around a second axis that intersects with the first axis; a moving device that moves a processing head including at least the objective optical system along a moving axis; Calculation unit and Equipped with the rotation device rotates the mounting device around the first axis to move the reference member from the eighth position to the ninth position, and rotates the mounting device around the second axis to move the reference member from the tenth position to the eleventh position; the light detection device acquires an eighth detection result by irradiating the reference member located at the eighth position with the measurement beam via the objective optical system located at the twelfth position, acquires a ninth detection result by irradiating the reference member moved to the ninth position with the measurement beam via the objective optical system located at the twelfth position, acquires a tenth detection result by irradiating the reference member located at the tenth position with the measurement beam via the objective optical system located at a thirteenth position, and acquires an eleventh detection result by irradiating the reference member located at the eleventh position with the measurement beam via the objective optical system located at the thirteenth position or a fourteenth position different from the thirteenth position, The calculation unit calculates a movement error occurring in movement of at least one of the placement device and the machining head based on position information of the reference member obtained using the eighth detection result, position information of the reference member obtained using the ninth detection result, position information of the reference member obtained using the tenth detection result, and position information of the reference member obtained using the eleventh detection result. The processing system according to any one of claims 1 to 12.

14. the mounting device includes a mounting surface on which the reference member is placed, the rotation device is capable of making the placement surface parallel to the direction of gravity and perpendicular to the direction of gravity by rotating the placement device around the first axis, the rotation device is capable of moving the reference member from the eighth position to the ninth position by rotating the placement device around the second axis when the placement surface is parallel to a direction of gravity, The rotation device is capable of moving the reference member from the tenth position to the eleventh position by rotating the placement device around the second axis when the placement surface is perpendicular to the direction of gravity. The processing system of claim 13.

15. the mounting device includes a mounting surface on which the reference member is placed, the rotation device rotates the mounting device around the first axis along the mounting surface so that the mounting surface becomes a surface along a traveling direction of the measurement beam; After the placement surface becomes a surface along the traveling direction of the measurement beam, (i) the photodetector irradiates the measurement beam onto the reference member located at the eighth position via the objective optical system located at the twelfth position, and then (ii) the rotation device rotates the placement device around the second axis intersecting both the placement surface and the first axis so that the reference member moves from the eighth position to the ninth position, and then (iii) the photodetector irradiates the measurement beam onto the reference member located at the ninth position via the objective optical system located at the twelfth position. The processing system according to claim 13 or 14.

16. The eighth position and the ninth position are aligned along the traveling direction of the measurement beam.

16. The processing system according to any one of claims 13 to 15.

17. The eighth position and the ninth position are located at the same position in a direction along a plane intersecting the traveling direction of the measurement beam, and are located at different positions in a direction along the traveling direction of the measurement beam.

17. The processing system according to any one of claims 13 to 16.

18. The rotation device rotates the placement device around the second axis so that the eighth position and the ninth position are located at two positions where a circle centered on the second axis intersects with a line passing through the center of the circle.

18. The processing system according to any one of claims 13 to 17.

19. The rotation device rotates the mounting device by 180 degrees around the second axis to move the reference member from the eighth position to the ninth position.

19. The processing system according to any one of claims 13 to 18.

20. the rotation device rotates the placement device multiple times while changing the rotation angle so that the reference member moves from the eighth position to the ninth position; The optical detection device irradiates the measurement beam onto the reference member located at the eighth position and the reference member located at the ninth position every time the rotation device rotates the mounting device.

20. The processing system according to any one of claims 13 to 19.

21. The reference member includes both a curved surface and a flat surface, the light detection device irradiates the measurement beam onto the flat surface of the reference member located at the eighth position and the flat surface of the reference member located at the ninth position; The photodetector irradiates the measurement beam onto the curved surface of the reference member located at the tenth position and the curved surface of the reference member located at the eleventh position.

21. The processing system according to any one of claims 13 to 20.

22. A processing beam for processing the workpiece can be irradiated onto the workpiece via the objective optical system, and the measurement beam can be irradiated onto the reference member.

22. The processing system according to any one of claims 13 to 21.

23. The moving device moves the objective optical system of the processing head so that the objective optical system follows the reference member that is moved by the rotation device rotating the placement device.

23. The processing system according to any one of claims 13 to 22.

24. a control unit that controls the moving device based on position information of the reference member obtained using each of the eighth detection result and the ninth detection result, and position information of the reference member obtained using each of the tenth detection result and the eleventh detection result.

24. The processing system according to any one of claims 13 to 23.

25. the calculation unit (i) calculates an ideal movement trajectory of the reference member that moves when the rotation device rotates the mounting device, based on position information of the reference member obtained using each of the eighth detection result and the ninth detection result; and (ii) calculates an actual measurement result of the movement trajectory of the reference member, based on measurement results of the reference member obtained using each of the tenth detection result and the eleventh detection result. The moving device is controlled based on the difference between the ideal movement locus of the reference member and the actual measurement result of the movement locus of the reference member.

25. The processing system of claim 24.

26. The reference member includes at least one of a curved surface and a flat surface.

26. The processing system of any one of claims 2 to 25.

27. The rotation device is controlled based on position information of the reference member obtained using the measurement beam.

27. The processing system of any one of claims 2 to 26.

28. Further, a moving device is provided to move the processing head along a moving axis, The moving device is controlled based on position information of the reference member obtained using the measurement beam. The processing system according to any one of claims 2 to 5.

29. a control unit that controls the moving device based on position information of the reference member obtained using the measurement beam 26. The processing system of any one of claims 13 to 25.

30. the moving device moves the processing head along a first movement axis, a second movement axis intersecting the first movement axis, and a third movement axis intersecting the first and second movement axes, the calculation unit calculates a movement error occurring in movement of the machining head along at least one of the first to third movement axes; The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error.

26. The processing system of any one of claims 13 to 25.

31. the rotation device is capable of rotating the placement device around a first axis; the calculation unit calculates a movement error occurring in movement of the mounting device along a rotation direction around the first axis, The rotation device moves the placement device based on the movement error calculated by the calculation unit so as to cancel out the movement error. The processing system according to any one of claims 2 to 14.

32. a moving device that moves the processing head along a first movement axis that extends in a vertical direction; the calculation unit calculates a movement error occurring in movement of the machining head along the first movement axis, The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error.

32. The processing system of any one of claims 2 to 14 and 31.

33. a moving device that moves the processing head along a second movement axis that extends horizontally and a third movement axis that extends horizontally and intersects with the second movement axis; the calculation unit calculates a movement error occurring in movement of the machining head along at least one of the second and third movement axes; The moving device moves the processing head based on the movement error calculated by the calculation unit so as to cancel out the movement error.

33. The processing system of any one of claims 2 to 14 and 31 to 32.

34. the light detection device is capable of irradiating the measurement beam onto the workpiece via the objective optical system during at least one of a first period before processing of the workpiece is started, a second period during which the workpiece is being processed, and a third period after processing of the workpiece is completed, and is capable of receiving at least a portion of light from the workpiece generated by irradiation of the measurement beam via the objective optical system; The calculation unit calculates at least one of the position and the shape of at least a part of the workpiece based on the detection result of the light detection device when the measurement beam is irradiated onto the workpiece.

34. The processing system of any one of claims 2 to 33.

35. a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a fifteenth position, and irradiates the measurement beam onto the reference member moved to an eleventh position via the objective optical system located at the fifteenth position, and further irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a thirteenth position, and irradiates the measurement beam onto the reference member moved to an eleventh position via the objective optical system located at a fourteenth position. Processing system.

36. a mounting device on which a workpiece can be placed and on which a reference member different from the workpiece can be placed; a light detection device that can irradiate a measurement beam for measuring the reference member via an objective optical system onto the reference member and can receive at least a portion of light from the reference member that is generated by the irradiation of the measurement beam; a driving device for moving the mounting device; Equipped with The photodetector irradiates the measurement beam onto the reference member located at a tenth position via the objective optical system located at a sixteenth position, irradiates the measurement beam onto the reference member moved to an eleventh position via the objective optical system located at the sixteenth position, and further irradiates the measurement beam onto the reference member moved to the eleventh position via the objective optical system located at a seventeenth position. Processing system.

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