JP2014074648A - Contact type shape measuring apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact type shape measuring apparatus and method, in which variation of a contact force or floating of a probe, which is caused by the fact that an inertia force is acted in a direction in which the probe is separated from or approaches a surface to be measured, is reduced so as to perform high-precision measurement.SOLUTION: In a contact type shape measuring apparatus having a probe and a stage for supporting the probe, in which by applying, while conveying the stage in a first direction, a prescribed contact force to the probe in a second direction different from the first direction, the probe is scanned along the surface to be measured to thereby measure a surface shape of the surface to be measured, there are provided gradient variation quantity derivation means for deriving a gradient variation quantity of the surface to be measured in the second direction in accordance with the conveyance quantity in the first direction, and correction force calculation means for calculating a correction force in a direction identical to the direction of the gradient variation quantity, and measurement is performed by adding a correction force to the prescribed contact force.

Description

  The present invention relates to an optical element and a contact-type shape measuring apparatus and method for measuring the shape of a molding die for manufacturing an optical element with high accuracy.

  As the functions of various optical devices such as imaging cameras, laser beam printers, and copiers become higher, the shapes of optical elements incorporated in these optical devices are becoming more complex. Under such circumstances, there is an increasing need for measurement of complicated shapes such as a surface shape with a small radius of curvature, a surface shape near the boundary between two surfaces, and a side surface shape with a small diameter. In order to measure the shape of an optical element having a complicated shape or a molding die for manufacturing the optical element, a contact-type shape measuring apparatus that measures the shape by scanning the probe is used.

  As an example of the prior art of a contact-type shape measuring device that measures the shape of a surface to be measured using an optical element or a molding die as an object to be measured, there is a shape measuring device disclosed in Patent Document 1. One end of the probe is brought into contact with the surface to be measured, and the three-dimensional position of the opposite end is measured. A spring mechanism is provided between the probe and the stage, and a contact force is obtained by pushing the stage from the balanced position. When the stage is driven in the XY direction, the probe follows the shape of the surface to be measured in the Z direction while moving in the XY direction. The stage is controlled to follow in the Z direction so as to maintain a pressing amount corresponding to a predetermined contact force. Measurement data is obtained by scanning the entire surface of the surface to be measured. Subsequently, the measurement data is analyzed to obtain shape information. The obtained shape information is used for evaluating the performance of the optical element or calculating the correction processing amount of the molding die.

  Here, it is known that the contact force between the probe and the surface to be measured should be reduced in order to cause the probe to accurately scan the surface to be measured. As a means for reducing the contact force, a contact type probe disclosed in Patent Document 2 can be cited. This contact probe incorporates a magnetic circuit comprising a yoke, a permanent magnet and a coil. The magnetic force generated by the magnetic circuit exerts a constant force that cancels the gravity applied to the probe and a force as a spring element that changes according to the displacement of the probe. Since the magnetic force is used, the contact force can be reduced and high-precision measurement can be performed.

Japanese Patent Laid-Open No. 10-19504 Japanese Patent Laid-Open No. 2003-047442

  FIG. 8 is a diagram for explaining a problem of the prior art. Fig.8 (a) is a figure explaining the subject at the time of measuring the surface shape of a small curvature radius. Examples of the measurement object having such a surface shape include a microlens array.

Probe 1, and the surface to be measured above w1 having a convex surface shape in the X direction is scanned at a constant velocity v _X. The gradient of the measured surface w1 at the position of p1 is set as g _p1 = Δz _p1 / Δx. Using the symbol Δ, the minute amount of a is expressed as Δa. The gradient of the measurement target surface w1 at the position of p2 after scanning the minute section Δx is set as g _p2 = Δz _p2 / Δx. When the probe 1 is scanning along the surface to be measured w1, the velocity of the probe 1 at the position of _p1 is v _p1 = v _X g _p1 . Similarly, the velocity of the probe 1 at the position of _p2 is v _p2 = v _X g _p2 . At this time, if the measured surface w1 is convex, the probe 1 is accelerated in a direction approaching the measured surface w1. The gradient change amount of the measured surface w1 from p1 to p2 is defined as h _p12 = (g _p2 −g _p1 ) / Δx = ((Δz _p2 −Δz _p1 ) / Δx) / Δx = Δ ² z _p12 / Δx ² Then, the acceleration of the probe 1 is
a _p12 = v _X ² h _p12
It can be expressed as. The acceleration in the direction in which the probe 1 approaches the surface to be measured w1 is normally generated by the contact force fc. In other words, when the contact force fc is zero, the acceleration in the direction approaching the measured surface w1 does not occur. Therefore, the probe 1 is separated in a direction away from the surface to be measured w1. In this way, the force that the probe 1 tries to move away from the surface to be measured w1 is generally called inertial force. The inertial force fi in the above is calculated as a value obtained by multiplying the acceleration _ap12 by the mass m of the probe 1.
fi = ma _p12 = mv _X ² h _p12
Since the inertial force fi works, the force that the probe 1 actually applies to the measurement target surface w1 is smaller than the predetermined contact force fc. Here, an actual contact force that is fluctuated by the inertial force fi is defined as an actual contact force fr.

  In a general contact-type shape measuring apparatus, the probe is in contact with the surface to be measured with a predetermined contact force. At this time, the probe receives a drag from the surface to be measured. When the surface to be measured is inclined with respect to the surface orthogonal to the probe longitudinal phrase, a component force of drag is applied in the direction orthogonal to the probe longitudinal direction. This component force causes the probe to fall. When one end of the probe is brought into contact with the surface to be measured and the three-dimensional position of the opposite end is measured, the probe tilt causes a measurement error. Usually, a probe shape calibration value is acquired in a state that includes probe tilting, and measurement data is calibrated using this shape calibration value. Therefore, if calibration is correctly performed, the influence on the measurement accuracy due to the tilting of the probe is small. However, when the contact force fluctuates, a difference occurs between the amount of probe collapse included in the shape calibration value and the actual amount of probe collapse. As a result, the influence on the measurement accuracy due to the tilting of the probe cannot be ignored. That is, the fluctuation of the actual contact force fr described above becomes a fluctuation of the tilting amount of the probe 1 and causes a measurement error.

  When the inertial force fi exceeds a predetermined contact force fc, the actual contact force fr becomes zero. This indicates that the probe 1 floats and does not follow the surface to be measured w1. If the probe 1 floats, the shape of the surface to be measured w1 cannot be copied to the probe, which clearly causes a measurement error.

Further, when the gradient change amount _{h p12} of the surface to be measured w1 is large, the inertia force fi is increased. That is, the smaller the radius of curvature of the surface to be measured w1, the greater the variation in the amount of probe tilt, and the greater the measurement error.

Increasing the scanning speed v _X, inertial force fi is increased. That is, as the probe is scanned at a higher speed, the variation in the amount of tilt of the probe increases and the measurement error increases.

  When the contact force fc is small, the threshold value at which the actual contact force fr becomes zero decreases. In other words, the smaller the contact force, the more easily the probe floats and the measurement error increases.

  So far, the convex shape has been described, but the same applies to the concave shape. In the case of a concave shape, the actual contact force fr increases due to the inertial force fi. As the contact force fr increases, the amount of probe tilt varies. Further, the drag from the surface to be measured increases, and the probe may be flipped up and floated. As described above, fluctuations in the amount of tilt of the probe and floating of the probe occur, causing measurement errors.

FIG. 8B is a diagram illustrating a problem when measuring the surface shape near the boundary between two surfaces. Examples of the measurement object having such a surface shape include a prism and a grating.

Probe 1, and are scanned at a constant velocity v _X on the measurement surface w2 in the X direction with a boundary so that two surfaces becomes a mountain type. Also in this case, the shape of the measured surface w2 changes sharply during the minute interval ΔX near the boundary between the two surfaces. Therefore, an inertial force fi that causes the probe 1 to leave as viewed from the surface to be measured w2 works. That is, fluctuations in the amount of probe tilt and probe floating occur, causing measurement errors.

FIG. 8C is a diagram for explaining a problem in measuring a small-diameter side surface shape. Examples of the measurement object having such a surface shape include a camera lens and a pickup lens.
Probe 1 is to be scanned over the cylindrical surface to be measured wb at a constant tangential velocity v _t. When the radius of curvature R of the cylinder is assumed, the angular velocity ω = Δθ / Δt is expressed as ω = v _t / R by dividing the tangential velocity v _t by the radius of curvature R. At this time, the probe 1 is accelerated by a _p12 = Rω ^{2 in the} center direction. In other words, when viewed from the measurement target surface wb, the inertial force that the probe 1 tries to leave is working. That is, fluctuations in the amount of probe tilt and probe floating occur, causing measurement errors.

  As described above, there is a problem that, as viewed from the surface to be measured, the inertial force acts in the direction in which the probe moves away from the surface to be measured or the phrase that approaches the surface, and the contact force varies. In particular, when the contact force is small, there is a problem that the probe floats. Accordingly, an object of the present invention is to provide a contact-type shape measuring apparatus and method for performing highly accurate measurement by reducing fluctuations in contact force due to the inertial force of the probe due to the shape of the surface to be measured and floating of the probe. To do.

  In order to achieve the above object, an invention according to the present application includes a probe and a stage that supports the probe, and a second direction different from the first direction with respect to the probe while feeding the stage in the first direction. In the contact-type shape measuring apparatus that measures the surface shape of the surface to be measured by applying a predetermined contact force to the surface to be scanned along the surface to be measured, according to the feed amount in the first direction, the second A gradient change amount deriving means for deriving the gradient change amount of the surface to be measured in the direction of and a correction force calculating means for calculating a correction force in the same direction as the gradient change amount, and applying the correction force to the predetermined contact force It is characterized by measuring.

  In addition, while supporting the probe on the stage and feeding the stage in the first direction, a predetermined contact force is applied to the probe in a second direction different from the first direction, so that the probe follows the surface to be measured. In a contact-type shape measuring method that scans and measures the surface shape of the surface to be measured, the gradient change amount of the surface to be measured in the second direction is derived according to the feed amount in the first direction, and the gradient change amount The correction force is calculated in the same direction, and the measurement is performed by adding the correction force to a predetermined contact force.

  According to the shape measuring apparatus and method of the present invention, the gradient change amount of the surface to be measured is derived according to the feed amount of the stage, and the correction force in the same direction as the gradient change amount is applied, so that the shape of the surface to be measured is obtained. It is possible to cancel the probe inertia force caused by the above and reduce the fluctuation of the contact force that the probe actually applies to the surface to be measured. Therefore, highly accurate measurement can be performed.

  Furthermore, by calculating the correction force by multiplying the gradient change amount by a coefficient, there is an effect that the fluctuation of the contact force that the probe actually applies to the measurement surface can be reduced more appropriately.

  Furthermore, when the first direction is on the XY plane of the Cartesian coordinate system and the second direction is the Z direction, the apparatus configuration is relatively simple, and the configuration is suitable for measuring the surface shape of the optical element. Become.

  Furthermore, if the first direction is on the contact surface of the surface to be measured and the second direction is the normal direction of the surface to be measured, the probe follows the normal direction of the surface to be measured. It becomes a suitable structure.

It is a figure explaining the structure of the contact-type shape measuring apparatus concerning the 1st Example of this invention. It is a flowchart explaining the method to calculate the correction force concerning 1st Example of this invention. It is a figure explaining the direction of the correction force concerning the 1st example of the present invention. It is a figure explaining the structure of the contact-type shape measuring apparatus concerning the 2nd Example of this invention. It is a figure showing the result of having computed the probe locus in the measurement of the surface shape of a small curvature radius. It is a figure showing the result of having computed the probe locus | trajectory in the measurement of the surface shape of the boundary vicinity of 2 surfaces. It is a figure explaining the structure of the contact-type shape measuring apparatus concerning the 3rd Example of this invention. It is a figure explaining the subject of a prior art.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram for explaining the configuration of a contact-type shape measuring apparatus according to the first embodiment of the present invention.

  The probe 1 supported by the stage 6 scans the surface to be measured w of the object 2 to be measured. The probe 1 is supported by the housing 4 via the linear guide 3. Thereby, it is possible to move in one axial direction with respect to the housing 4. That is, the linear guide 3 has a structure in which the frictional resistance and the viscous resistance are reduced in the moving direction so as to move easily, and the rigidity is increased in the direction orthogonal to the moving direction so that the linear guide 3 is difficult to move. Examples of means for obtaining such characteristics include an air bearing. A spring mechanism 5 is provided between the probe 1 and the housing 4. The housing 4 is attached to the tip of the lower surface 6a of the stage 6 facing the object 2 to be measured. The DUT 2 is placed on the pedestal 14.

  A through hole 6b is provided at the tip of the stage 6 to which the housing 4 is attached. The three-dimensional position data of the mirror 1m attached to the end 1d in the axial direction of the probe 1 is measured (described later). The measurement data at the three-dimensional position is sent to the measurement data calculation means 13 via the signal line 20 and the signal line 21. The measured data of the measured three-dimensional position is also transmitted to the Z drive control means 12 via the signal line 20 and the signal line 22.

  The probe 1 includes a probe shaft 1a, a probe tip 1b attached to one end of the probe shaft 1a in the axial direction, and a sphere 1c arranged at the tip of the probe tip 1b. The probe shaft 1 a is supported so as to be movable in the axial direction by a linear guide 3 disposed at the tip of a flange portion 4 a extending inward from the wall of the housing 4. The flange portion 4 a is provided at two locations at a predetermined interval in the axial direction of the housing 4.

  As shown in FIGS. 3 and 7, a sphere 1c arranged at the tip of the probe tip 1b is inserted into the probe shaft 1a and fixed to the tip of a probe rod 1d that can be extended to the outside. Accordingly, the sphere 1c protrudes from the tip of the probe tip 1b according to the extension of the probe rod 1d.

  The spring mechanism 5 functions as a spring element that generates a force according to the relative position between the probe 1 and the stage 6 in the direction along the movement axis of the linear guide 3. Here, the movement axis of the linear guide 3 is the gravity direction (Z direction). Examples of the spring mechanism 5 include a plate spring using material rigidity and a magnetic spring using magnetic force. Further, although the linear guide 3 and the spring mechanism 5 are configured separately, two functions can be obtained as an integrated configuration. For example, the structure which attaches two leaf | plate springs on the probe 1 in parallel is mentioned.

  Regarding the relative position of the probe 1 and the stage 6 in the Z direction, a position where the gravity applied to the probe 1 and the force generated by the spring mechanism 5 are balanced is defined as a neutral position. When the stage 6 is pushed from the neutral position while the probe 1 is in contact with the surface to be measured w, a force according to the pushed amount is applied to the probe 1. In this way, the force applied to the probe 1 is defined as the contact force. In the static state, the same force as the contact force applied to the probe 1 is also applied in the Z direction of the surface to be measured w. Further, the amount of pushing the stage 6 from the neutral position is defined as the pushing amount.

  A mirror 1m is attached to the other end 1d in the axial direction of the probe 1, and the three-dimensional position of the probe 1 can be measured using laser measurement or the like. A mirror 6m is attached to the upper surface 6c of the end located further on the tip than the through hole 6b of the stage 6, and the three-dimensional position of the stage 6 can be measured similarly. The measurement data of the three-dimensional position obtained by the mirror 6m is sent to the Z drive control means 12 via the signal line 23 and the signal line 22. Also, the relative position in the Z direction can be obtained from the measurement data of the three-dimensional positions of the probe 1 and the stage 6.

  A Z driving means 7 and an XY driving means 8 are attached to the stage 6. The Z drive means 7 can drive the stage 6 in the Z-axis translation direction. The XY drive unit 8 can drive the stage 6 in the XY axis translation direction. Here, the drive shaft of the drive means for driving the stage 6 may be appropriately changed such as a translation direction, a rotation direction, or a combination thereof. The XY drive unit 8 is placed on the base member 15.

  When the XY driving unit 8 is driven to move the stage 6 on the XY plane (first direction) of the orthogonal coordinate system, the probe 1 follows the shape of the surface to be measured w in the Z direction while moving in the XY direction. . At this time, the Z driving means 7 is also driven by the method described later.

  The gradient change amount deriving unit 10 derives information on the gradient change amount h of the measured surface w stored in advance and sends the information to the correction force calculating unit 11. The correction force calculator 11 calculates the correction force fa based on the information on the gradient change amount h. Thereafter, information on the correction force fa is sent to the Z drive control means 12. Information on the relative position of the probe 1 and the stage 6 in the Z direction (second direction) is also sent to the Z drive control means 12.

  The Z drive control means 12 stores in advance a push amount A necessary for generating a predetermined contact force fc. Further, the pushing amount B of the stage 6 necessary for generating the correction force fa is obtained. The total amount of the push amount A and the push amount B is the target push amount. The Z drive control means 12 obtains the drive amount in the Z direction of the stage 6 so that the difference between the current push amount and the target push amount becomes small. The current pushing amount can be obtained from the relative position of the probe 1 and the stage 6 in the Z direction. Information on the obtained drive amount is sent to the Z drive means 7. The Z drive means 7 drives the stage 6 in the Z direction based on the drive amount information. If the stage 6 has a target pushing amount, a force obtained by adding a predetermined contact force fc and a correction force fa is applied to the probe 1.

  The measurement data of the three-dimensional position of the probe 1 is also sent to the measurement data calculation means 13. After acquiring the measurement data by scanning the entire surface to be measured w, the measurement data calculation means 13 analyzes the measurement data as necessary and outputs it as shape information. The shape information is used for evaluating the performance of the optical element or calculating the correction processing amount of the molding die.

  Next, a method for calculating the correction force fa will be described with reference to the flowchart of FIG.

  Calculation is started in S101. In S102, a discrete time Δt for applying the correction force fa is determined. In step S103, a stage feed coordinate point sequence {s} is determined in the stage feed direction. {} Represents point sequence data. When sending the stage in the XY direction, {s} = {(X, Y)}. In S104, a stage feed speed point sequence {v} = {(vX, vY)} corresponding to the stage feed coordinate point sequence {s} is determined. The XY driving means 8 is driven based on the stage feed coordinate point sequence {s} and the stage feed speed point sequence {v}. Thereby, the stage 6 can be moved in the X and Y directions along the designated scanning locus. The movement of the probe 1 in the XY direction is also determined according to the movement of the stage 6 in the XY direction.

Next, in S105, a gradient change point sequence {h} = {Δ ² Z / Δs ² } representing the gradient change amount h of the measured surface is determined. Here, {Δs} is {Δs} = {v} Δt. In S106, the correction force point sequence {fa} = α {v ² h} = α {v ² (Δ ² Z / Δs ² )} is calculated and calculated. α is a correction force coefficient. When the correction force coefficient α is set equal to the mass m of the probe 1, the correction force fa becomes equal to the inertial force fi. Actually, it is determined in consideration of measurement error of mass m, measurement noise and the like. If the correction force point sequence {fa} is previously calculated in correspondence with the stage feed coordinate point sequence {s}, the corresponding correction is performed at the timing when the stage 6 passes a certain coordinate on the stage feed coordinate point sequence {s}. A force fa can be applied to the probe 1. Here, although the discrete time Δt is described as being uniform, it may be variable according to the location so that it is finely set at a place where the gradient change amount h is steep and coarsely set at a place where the gradient change amount h is gentle. good. In S107, the calculation ends.

  FIG. 3 is a diagram for explaining the direction of the correction force according to the first embodiment of the present invention. FIG. 3A shows the direction of the correction force fa in the case of a convex measured surface. Since the measured surface w is on the lower side in the Z direction, the predetermined contact force fc is applied downward. Further, if the measured surface w is convex, the gradient change amount h is downward. When the gradient change amount h is downward, the inertial force fi works upward in the direction opposite to the gradient change amount h. Here, the purpose of the correction force fa is to reduce the fluctuation of the actual contact force fr due to the inertial force fi acting as described above. Therefore, the correction force fa is applied downward in the direction opposite to the inertia force fi.

  FIG. 3B shows the direction of the correction force fa when the surface is a concave measurement surface. In the case of a concave surface to be measured, the gradient change amount h is upward. When the gradient change amount h is upward, the inertial force fi works downward in the direction opposite to the gradient change amount h. Therefore, the correction force fa is applied upward.

  As described above, the correction force fa is in the same direction as the gradient change amount h. If the correction force fa in the same direction as the gradient change amount h is applied, the correction force fa and the inertia force fi cancel each other, and the fluctuation of the actual contact force fr can be reduced. If fluctuations in the actual contact force fr can be reduced, fluctuations in the probe tilt amount and occurrence of probe floating can be suppressed. That is, highly accurate measurement can be performed.

  FIG. 4 is a diagram for explaining the configuration of the contact-type shape measuring apparatus according to the second embodiment of the present invention. In the second embodiment, correction force generating means 9 is added to the first embodiment. Therefore, the description of the same part as the first embodiment is omitted. The correction force generating means 9 is composed of a magnetic circuit composed of a yoke, a permanent magnet, and a coil (each not shown). Based on the correction force information received from the correction force calculation means 11, the current flowing in the coil is controlled. Thereby, a correction force is applied to the probe 1. With such a configuration, the correction force can be controlled at a higher speed than the configuration in which the correction force is applied by controlling the push amount of the stage 6 as in the first embodiment.

  FIG. 5 is a diagram showing the result of computer calculation of the probe trajectory in the measurement of the surface shape with a small radius of curvature. The probe locus (XZ direction) when the stage is sent in the X direction is shown. The horizontal axis is the X direction, and the vertical axis is the Z direction. The probe trajectory 101 is a case where the apparatus of the present invention is used. The probe trajectory 102 is a case where a conventional apparatus is used. The surface to be measured is a convex spherical surface having a curvature radius of 1 mm. The probe mass is 10 g. The stage is sent from the left side (the side where the tilt angle is gentle) to the right side (the side where the tilt angle is steep) in FIG. The stage feed speed is 2 mm / s. The horizontal axis represents the inclined surface from about 45 ° to about 90 °. When the two probe trajectories are compared, the difference between the two is large on the right side of FIG. This shows a state in which the probe trajectory 101 is scanning the surface to be measured while the probe trajectory 102 is away from the surface to be measured and is floating.

  FIG. 6 is a diagram showing the result of computer calculation of the probe trajectory in the measurement of the surface shape near the boundary between the two surfaces. The probe locus (XZ direction) when the stage is sent in the X direction is shown. The horizontal axis is the X direction, and the vertical axis is the Z direction. The probe locus 201 is a case where the apparatus of the present invention is used. The probe trajectory 202 is a case where a conventional apparatus is used. The surface to be measured is a surface having a mountain shape with both opening angles of 150 °. If they are installed symmetrically, it can be said that the surface has a boundary between an upward inclined surface of 15 ° and a downward inclined surface of 15 °. The probe mass is 10 g. The stage is sent from the left side (upward inclined surface side) to the right side (downward inclined surface side) of FIG. The stage feed speed is 2 mm / s. When the two probe loci are compared, the difference between the two is large with the peak of the mountain shape as the boundary. This shows a state in which the probe trajectory 201 scans the surface to be measured while the probe trajectory 202 is separated from the surface to be measured and floats.

  From the above two results, it can be seen that by applying a correction force in the same direction as the gradient change amount, the inertial force can be canceled out, and fluctuations in the contact force actually applied to the surface to be measured and probe floating can be suppressed. . Therefore, highly accurate measurement can be performed.

  FIG. 7 is a diagram for explaining the configuration of a contact-type shape measuring apparatus according to the third embodiment of the present invention. In the third embodiment, instead of the linear guide 3 driven in the Z direction, a rotation guide 3b rotating around the X axis and the Y axis is attached. Further, instead of the Z drive means 12, an XY drive control means 12b is attached. Information on the drive amount from the XY drive control means 12 b is sent to the XY drive means 8. This makes it easy to measure the cylindrical side surface wb of the DUT 2.

  In the present embodiment, the probe 1 measures the surface shape by bringing a sphere 1c attached to the tip of a probe rod 1d extending from the probe tip 1b into contact with the cylindrical side surface wb of the object 2 to be measured.

  A specific driving method applies contact force in the normal direction of the side surface while feeding the stage 6 onto the contact surface of the side surface. Alternatively, a contact force is applied in the Y direction (or X direction) while feeding the stage 6 to the XZ plane (or YZ plane). According to such a configuration, even on a vertical surface such as the cylindrical side surface of the object 2 to be measured, the contact actually applied to the measurement surface by applying a correction force corresponding to the inertial force to the predetermined contact force. Force fluctuations and probe lift can be suppressed.

DESCRIPTION OF SYMBOLS 1 Probe 2 Measured object 6 Stage 9 Correction force generation means 10 Gradient change amount derivation means 11 Correction force calculation means 12 Z drive control means 12b XY drive control means 13 Measurement data calculation means fa Correction force fc Predetermined contact force fi Inertial force fr actual contact force h gradient change amount w, wb surface to be measured 101, 201 probe trajectory 102, 202 according to the present invention probe trajectory according to the prior art

Claims (5)

  A probe and a stage for supporting the probe, and applying the predetermined contact force to the probe in a second direction different from the first direction while feeding the stage in the first direction, the probe to be measured In the contact-type shape measuring device that measures the surface shape of the surface to be measured by scanning the surface of the surface, the gradient change that derives the gradient change amount of the surface to be measured in the second direction according to the feed amount in the first direction A contact-type shape measuring apparatus comprising: a quantity derivation unit; and a correction force calculation unit that calculates a correction force in the same direction as the gradient change amount, and performs measurement by adding the correction force to a predetermined contact force.   The contact-type shape measuring apparatus according to claim 1, wherein the correction force is calculated by multiplying the gradient change amount by a coefficient.   The contact-type shape measuring apparatus according to claim 1, wherein the first direction is a direction on an XY plane of an orthogonal coordinate system, and the second direction is a Z direction.   The contact-type shape measuring apparatus according to claim 1, wherein the first direction is a direction on the contact surface of the surface to be measured, and the second direction is a normal direction of the surface to be measured.   By supporting the probe on the stage and feeding the stage in the first direction, applying a predetermined contact force to the probe in a second direction different from the first direction, the probe is scanned following the surface to be measured. In the contact-type shape measuring method for measuring the surface shape of the measured surface, the gradient change amount of the measured surface in the second direction is derived according to the feed amount in the first direction, and is the same as the gradient change amount. A contact-type shape measuring method, wherein a correction force is calculated for a direction, and the correction force is added to a predetermined contact force for measurement.

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