JPH06147886A - Surface profile measuring equipment - Google Patents

Abstract

PURPOSE:To deal with complicated profile including nonspherical profile by satisfying contradictory requirements of suppression of damage on the surface to be measured and high speed measurement through high response load control while enhancing accuracy and speed of measurement and enlarging the measuring range. CONSTITUTION:The body of the equipment comprises a frame 4 which functions as the reference of movement of a mover 3, and a controller (not shown), wherein the mover 3 is formed on the frame 4 such that an actuator 5 drives the mover 3 vertically by a microdistance. A mover displacement detecting means 7 for detecting displacement of the mover 3 is disposed on the top surface of the mover 3 having bottom surface secured with a parallel spring 2. A probe 1 is provided integrally or detacluably to one end part of the parallel spring 2 while directing vertically downward and an elastic body displacement detecting means 6 for detecting the displacement of the parallel spring 2 is disposed while spaced apart therefrom. An object 9 to be measured is held on a stage 8 below the probe 1 while directing the surface to be measured upward and the stage 8 is installed movably up and down.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact type surface profile measuring apparatus, and in particular, it eliminates the influence of flaw generation or measurement load variation on a measurement result when measuring with a stylus or stylus, The present invention relates to a device for performing high-speed measurement by following highly responsiveness.

[0002]

2. Description of the Related Art A stylus (hereinafter referred to as a stylus) for measuring nm order by a contact type surface profile measuring device.
Elastic deformation at the contact point of the stylus on the surface to be measured due to flaws (scanning traces) at the time of measurement by the "stylus" collectively and measurement load adversely affects the measurement results. The generation of flaws during measurement depends on the material of the object to be measured and the relationship between the shape and size of the stylus and the measured load. For example, precision machine 5
1/4/1985, p. 674-P. 680 (Kouzo Miyamoto: Surface shape measurement by contact type and non-contact type) appears as a plastic conversion region between the stylus samples, that is, a flaw, depending on the size of the stylus tip radius even if the same measurement load is applied to the same material. It is analytically shown from Hertz's elastic contact theory that the areas of the regions are different. Further, the shape and size of the stylus and stylus are restricted by the geometric shape conformability to the surface shape to be measured in addition to the generation of flaws. In this respect, for example, APPLIED OPTIC
S, 15 May 1981, Vol. 20, No. 10,
P. 1785-1802 (JMBennett: Stylus profili
ng instrument for measuring statistical properties
of smooth optical surfaces) has a report on shape tracking and the occurrence of flaws. As a method for solving the problems related to the flaws and the shape followability during scanning, the STM
And AFM, which perform non-contact scanning utilizing surface characteristics (for example, tunneling current and interatomic force) and contact scanning with an extremely light load (nN to μN order). These are generally 0.1μ in tip radius for observing ultrafine structures.
Although a stylus of m or less is used, the stress state at the contact point between the stylus and the surface to be measured is severe, and the amount of elastic deformation of the surface to be measured due to the measurement load affects the measurement result as an error. The study on this point and the development of the measuring device are National
Technical Report, Vol. 36, N
o. 2, Apr. 1990, P.I. 232-239 (Keiichi Yoshizumi et al.) And 1989 Precision Engineering Society Autumn Academic Lecture Proceedings. 541-542 (Oguchi, Kaneko: Development of ultra-light load stylus type surface profile measuring instrument)
An example can be seen in 95301.

[0003]

A conventional contact-type surface profile measuring device for the problems of the generation of flaws and elastic deformation due to the stylus is as follows.
Many devices satisfy the probe tip radius and the corresponding measurement load as shown in B0651. In thin-film step measuring instruments, etc., the only way to reduce damage to the surface to be measured by making the measuring load extremely low is that the coordinate measuring machine controls the measuring load, but the stylus diameter is on the order of mm. Therefore, it is difficult to say that an effective approach is taken when considering the shape accuracy of the stylus itself. Especially in the roughness meter
As shown in 1-200509, generally, there are a lot of eccentric constitutions. Shigeyasu Amioka: Mechanism design of precision measuring instrument, development company, 19
No measures are taken against the fluctuation of the measured load during scanning as pointed out in 70 as well.

Flaws at the time of measurement due to high precision of measurement,
While it is necessary to solve the elastic deformation problem, at the same time, high speed measurement is required. As aspherical optical components such as CD pickup lenses are becoming more aspherical, evaluation of complex shapes is becoming more important. However, evaluation of complex shapes requires more measurement points or a wider range of shape data, and the number of scans However, the measurement time is increased. It seems that the aspherical surface of optical parts will be widely used in toric lenses for scanning optical systems, projector lenses, and short-wavelength optical elements (toroidal mirrors, parabolic mirrors, etc.). It is important to realize high speed.

A problem in increasing the speed of contact-type surface measurement is the resonance frequency of the system consisting of the contact rigidity between the stylus and the surface to be measured and the mass of the stylus. In high-speed scanning, the stylus is required to follow the frequency component represented by the product of the spatial frequency of the surface to be measured and the scanning speed. However, in order to reduce damage to the surface to be measured, such as the occurrence of flaws and the amount of elastic deformation, it is necessary to make the measurement load extremely low. At this time, as can be seen from Hertz's elastic contact theory, The contact rigidity between the measurement surfaces is low. As a result, the resonance frequency of the spring-mass system consisting of the stylus and the surface to be measured becomes low, and such a point makes it difficult to achieve both a low load and a high measurement speed that reduces damage to the surface to be measured. ing. An effective measure to increase the resonance frequency of the spring-mass system consisting of contact rigidity and stylus is to reduce the weight of the stylus. That point,
The roughness meter is advantageous because the stylus portion is light, weighing several tens of mg, but it is difficult to measure complex shapes because the measurement range is narrow and the measurement load is narrow. In the case of a coordinate measuring machine, high-speed measurement is difficult because load control and measurement are applied to one axis. JP-A-60-64206,
As can be seen in JP-A-62-277501, JP-A-3-100415 and the like, there are many measuring probes in which a stylus is supported by a parallel spring, a measuring load is controlled by a coil magnet, and a displacement is detected by a differential transformer. Since the stylus diameter is large, the contact rigidity between the stylus and the surface to be measured is high and the contact is stable.However, since the components are large, high response of load control cannot be expected, and the increase in measurement time with the increase in the number of measurement points Inevitable. Also, the size of the stylus itself limits the geometrically conformable shape, and it is difficult to deal with the complicated shape required for aspherical optical components.

The present invention has been made in view of the above problems of the prior art, and reduces the damage to the surface to be measured such as the generation of scratches and the elastic deformation at the contact point of the stylus and the load control with high responsiveness. The object is to provide a surface profile measuring device that meets the contradictory requirements of high-speed measurement by using, and is capable of dealing with complex shapes such as aspherical shapes by increasing the measurement accuracy and speed and expanding the measurement range. There is.

[0007]

According to the present invention for achieving the above object, a contact surface of a measured object is contact-scanned with a stylus, and a displacement amount of the measured surface is used. In a surface shape measuring device for measuring a surface shape, a moving body provided at a position facing the surface to be measured, which has high responsiveness in a direction facing the surface to be measured and is capable of minute movement, and the moving body. A load control that is fixedly attached to the measuring surface, and the stylus whose tip is directed to the measuring surface is configured to be displaceable with respect to the measuring surface and attachable or integrally provided with an elastic body. A mechanism, a displacement detection unit that is disposed separately from each of the elastic body and the moving body, and that detects each displacement amount of the elastic body and the moving body; and the load according to the detection result of the displacement detection unit. Has a control device that controls the control mechanism The control device applies a load to a set load while bringing the stylus into contact with the surface to be measured by the movement of the moving body, and a difference between a displacement amount of the moving body and a displacement amount of the elastic body is equal to the set load. It is characterized in that the position of the moving body is controlled so as to be always equal to the corresponding displacement amount.

[0008] Further, the measuring device or the load control mechanism is equipped with one of them, and a holding base movable opposite to the measuring object or the load control mechanism is provided. Is above the movement range, the holding table is moved so that the difference between the displacement amount of the movable body and the displacement amount of the elastic body is always equal to the displacement amount corresponding to the set load. The position of the holding table may be controlled together with the position control.

[0009]

In the surface shape measuring apparatus of the present invention, the moving body provided with a high responsiveness to the surface to be measured and capable of making a minute movement is moved toward the surface to be measured by the control device, and is moved to the moving body. At the same time as the tip of the stylus provided on the fixed elastic body is brought closer to the surface to be measured, each displacement amount is monitored by each displacement detection means separately arranged on the moving body and the elastic body. , The amount of displacement of the moving body and the elastic body is detected. At this time, it is confirmed whether or not the displacement amounts of the moving body and the elastic body monitored from the respective displacement detecting means arranged are equal, and when they are equal, it is determined that the stylus is not in contact with the surface to be measured yet. , Keep moving the moving body. If they are not equal, it is determined that the stylus is in contact, and the difference between the displacement amounts of the moving body and the elastic body is detected. This difference in the amount of displacement corresponds to the amount of displacement of the elastic body itself, and if the spring constant of the elastic body is known, the load applied to the measured surface can be obtained. The load is controlled so that the load is always equal to a preset load, and the surface of the surface to be measured is contact-scanned, and the change amount of the displacement amount of the elastic body is output from the displacement detecting means of the elastic body. The surface shape of the measured surface is measured.

Further, in addition to a load control mechanism composed of a movable body and an elastic body as a configuration of the entire apparatus, a load control mechanism in which the tip of the stylus is directed to the surface to be measured or the tip of the stylus is covered. By providing a holding table on which either one of the measured objects facing the measurement surface is mounted and making it possible to move oppositely,
The control device changes the surface shape of the surface to be measured at the time of measurement, so when the moving body exceeds the moving range, the holding table is moved and the load applied to the surface to be measured is set in advance. The load is controlled so that it is always equal to the load. In this case, the surface shape of the surface to be measured is measured by adding the displacement amount of the holding table to the change amount of the displacement amount of the elastic body output from the displacement detecting means of the elastic body.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.

(First Embodiment) FIG. 1 is a perspective view showing the features of the main constitution of the first embodiment of the surface profile measuring apparatus of the present invention. FIG. 2 is a side view of the first embodiment of the surface profile measuring apparatus of the present invention.

The apparatus main body 10 of the present embodiment has a frame 4 serving as a movement reference of the moving body 3 and a control device (not shown). The moving body 3 which is a parallel spring fine movement stage includes a piezoelectric element or the like in the frame 4. The actuator 5 is formed so as to be finely movable in the vertical direction by being driven. On the upper surface of the moving body 3, moving body displacement detecting means 7 for detecting the amount of displacement of the moving body 3.
, And the parallel spring 2 as an elastic body is fixedly installed on the lower surface of the moving body 3. A stylus 1 having its tip end facing vertically downward is attached to or integrally provided at one end of the parallel spring 2, and an elastic body displacement detecting means 6 for detecting the displacement amount of the parallel spring 2 is arranged separately. ing.

In the parallel spring of this embodiment, as the elastic body 2 for load detection, an integrated parallel spring formed by wire cutting is used because of concern about the non-linear behavior of each member fastening portion of the assembly type parallel spring under a low load. ing. This parallel spring can be manufactured using a normal wire cutting machine with a wire diameter of 0.2 mm.
Thus, it is possible to realize a leaf spring dimension of about 3 × 7 × 0.07 mm and a spring constant of 1000 N / m or less. The above-mentioned moving body displacement detecting means 7 and elastic body displacement detecting means 6 have a high response frequency such as a laser interferometer or an optical fiber type displacement meter in order to realize high-speed load control using feedback control. Those with less delay are better.

An object to be measured 9 whose surface shape is measured is held below the stylus 1 on a stage 8. The stage 8 is installed so as to be movable in the vertical direction separately from the movement of the moving body 3. .

Next, the operation of the first embodiment by the controller of the surface profile measuring apparatus according to the present invention will be described with reference to FIG. FIG. 3 is a flow chart showing the operation of the first embodiment of the present invention.

The control device of this embodiment first moves the moving body 3 downward, and brings the stylus 1 closer until it comes into contact with the surface to be measured of the object 9 to be measured (step S1). At this time, the displacement amounts of the moving body 3 and the parallel spring 2 as the elastic body from the frame 4 which is the movement reference are monitored by the moving body displacement detecting means 7 and the elastic body displacement detecting means 6, respectively.

Then, it is confirmed whether or not the displacement amount of the moving body 3 and the displacement amount of the parallel spring 2 are equal (step S2). When the displacement amounts are equal, the process returns to S1 again and repeats the movement operation so that the displacement amounts are equal. If it is confirmed that there is no stylus, it is determined that the stylus is in contact (S3). This is because the parallel spring 2 is pushed upward by the surface to be measured after the contact, and the displacement amount of the movable body 3 becomes larger than the displacement amount of the parallel spring 2. At this time, the difference between the amounts of displacement of the parallel spring 2 and the moving body 3 is the amount of displacement of the parallel spring 2 itself as an elastic body.

When it is determined in S3 that they are in contact with each other, it is confirmed whether the difference between the displacement amounts of the parallel spring 2 and the moving body 3 is smaller than the elastic body displacement amount corresponding to the set load (S).
4) If it is smaller, the mobile unit 3 continues to move downward (step S4). When it is confirmed in S4 that the difference between the displacement amounts of the parallel spring 2 and the moving body 3 becomes equal to the elastic body displacement amount corresponding to the set load, the movement of the moving body 3 is temporarily stopped (step S6), and the load is changed. Control is started (step S7).

FIG. 4 is a schematic diagram showing a load control state during measurement scanning in the surface profile measuring apparatus of the present invention.

When the surface of the surface to be measured 9 is contact-scanned, as shown in FIG.
As shown in Fig. 4, the position control of the moving body 3 is performed by the actuator 5 such as a piezoelectric element so that the difference between the displacement amounts of the parallel spring 2 and the moving body 3 is always equal to the elastic body displacement amount corresponding to the set load. It is achieved by doing.

When the surface shape changes exceeding the stroke of the actuator 5 during measurement, the stage 8 is moved in the vertical direction, and the difference between the displacement amounts of the parallel spring 2 and the moving body 3 corresponds to the set load. The position of the stage 8 is controlled so as to be always equal to the elastic body displacement amount.

The measurement data is usually the elastic body displacement detection means 6
In the above case, it is obtained by adding the displacement amount detected by the elastic body displacement detecting means 6 and the displacement amount of the stage 8.

In the present embodiment, damage to the surface to be measured is suppressed by controlling the load, and the moving body 3 capable of high-speed response ensures tracking of the high spatial frequency component of the shape of the surface to be measured. The cooperative operation of the mobile unit 3 enables a wide range of measurement.

(Second Embodiment) FIG. 5 is a perspective view showing a second embodiment of the main structure of the surface profile measuring apparatus of the present invention. FIG. 6 is a front view of the second embodiment of the surface profile measuring apparatus of the present invention.

As shown in FIGS. 5 and 6, the apparatus main body 20
Has a stage 18 for supporting the movement in the vertical direction and a controller (not shown), and the stage 18 is equipped with a moving body attachment guide portion 14. The moving body mounting guide portion 14 is a mounting member of the moving body 13 and is a guide portion having an aerostatic bearing surface and a linear motor coil integrated therewith. The moving body 1 is attached to the moving body attachment guide portion 14.
3 is attached so as to be movable in the vertical direction, and the moving body 13 is finely moved by an actuator 15 using a piezoelectric element or the like installed on the upper surface of the moving body 13.

An elastic hinge utilizing a circular arc notch is adopted for the moving body 13, and in order to offset the lateral movement when the elastic hinge is deformed, the mechanical engineering journal, 55/1 / 1989P.
146 to 151 (Nobuhiro Tsuda et al .: Large stroke STM) uses an elastic hinge having a multi-folded and folded structure with an integral structure.

On the upper surface of the moving body 13, moving body displacement detecting means 17 for detecting the amount of displacement from the first reference position is arranged separately. On the other hand, on the lower surface of the moving body 13, the AFM
A thin leaf spring 12 similar to the cantilever used for is attached as an elastic body for load detection. Thin leaf spring 1
In the processing of No. 2, since the dimension and shape are adjusted by etching the thin plate member, the degree of freedom of the design shape is relatively high, and the spring setting can be easily changed in a wide range. Further, in this embodiment, the thin leaf spring having a V-shape is constructed so as to have a rigid structure against a moment due to a frictional force acting on the tip of the stylus. A stylus 11 having a vertically downward tip is freely or integrally attached to the tip of the V-shaped thin leaf spring, and an elastic body displacement detecting means for detecting the amount of displacement of the thin leaf spring 12. 16 are spaced apart.

In the operation by the control device of this embodiment, the displacement amount is detected by the moving body displacement detecting means 17 and the elastic body displacement detecting means 16 as in the first embodiment, and the load is controlled to measure the surface shape. To do. If the shape of the moving body 13 exceeds the stroke, the moving body 13 is moved by the moving body mounting guide portion 14 to deal with the change.

With the above structure, the same effect as that of the first embodiment can be obtained.

(Third Embodiment) FIG. 7 is a perspective view showing a third embodiment of the main constitution of the surface profile measuring apparatus of the present invention.

The apparatus main body of this embodiment has moving body guide portions 24a and 24b for guiding the moving body 23 in the vertical direction by static pressure and a controller (not shown), and moves the moving body 23 in the vertical direction. A coil portion 25 for causing the movement is installed. A coil as a linear motor is provided in the coil portion 25, and a yoke portion 26 is installed on the upper surface of the coil portion 25. The moving body 23 is provided on the yoke portion 26.
Is fixed, and the moving body 23 is provided so as to be finely movable in the vertical direction by the moving body guide portions 24a and 24b. Moving body displacement detecting means 28a and 28 for detecting the amount of displacement of the moving body 23 are provided on the upper surface of the moving body 23 located in the vicinity of the respective moving body guiding portions 24a and 24b.
b are spaced apart. A hole is formed in the center of the moving body 23, and cross-shaped thin leaf springs 22a and 22 as elastic bodies for load detection are provided at the upper and lower ends of the hole, respectively.
b is fixed. A stylus 21 is detachably or integrally attached to the cross-shaped thin leaf springs 22a and 22b fixed above and below the moving body 23 so as to pass through the central portion of each thin leaf spring with its tip facing vertically downward. . The cross-shaped thin leaf springs 22a and 22b are configured to improve rigidity against moment load (for example, frictional force) acting on the tip of the stylus 21 during contact scanning. Elastic body displacement detection means 27 for detecting the amount of displacement of a cross-shaped thin leaf spring as an elastic body is spaced apart from one end of the stylus 21.

The operation of measuring the surface shape by the control device of this embodiment is almost the same as that of the first and second embodiments, but in order to correct the influence of yawing of the moving body 23 at the time of measurement, the moving body is moved. The average value of the displacement amounts of both detected by the displacement detection means 28a and 28b is taken as the displacement amount of the moving body 23, and the difference from the displacement amount detected by the elastic body displacement detection means 27 is calculated, and this difference is constant. The load is controlled so that

(Fourth Embodiment) FIG. 8 is a partial sectional perspective view showing the structure of a measuring head of a fourth embodiment of the surface profile measuring apparatus of the present invention. FIG. 9 is a perspective view showing a fourth embodiment of the surface profile measuring apparatus of the present invention.

As shown in these figures, the apparatus main body 43 of this embodiment has a control device (not shown), and a measuring head 39 and a stage 41 holding an object 40 to be measured are provided on the upper surface of the apparatus main body 43. A stage slider 42 is provided so as to be opposed to the measurement head 39 and the stage 41 is movable with respect to the measurement head 39. The measuring head 39 has a base 38, and on the upper surface of the base 38 is provided a frame 34 that is the movement reference of the moving body 33 similar to the above-described first embodiment. The frame 34 is a parallel spring fine movement stage. The moving body 33 is P
It is formed so that it can be moved minutely by driving an actuator 5 such as a ZT element. Actuator 3 of moving body 33
The moving body displacement detecting means 37 for detecting the amount of displacement of the moving body 33 is spaced apart from the surface displaced by 5, and on the other hand, one surface of the moving body 33 on the side of the object to be measured 40 serves as an elastic body. The parallel spring 32 is fixedly installed. A stylus 31 having a tip end facing the object to be measured 40 can be attached to or integrally provided with one end of the parallel spring 32, and an elastic body displacement detection means 36 for detecting the displacement amount of the parallel spring 32 is provided. It is separated.

In the operation by the control device of this embodiment, the displacement amount is detected by the moving body displacement detecting means 37 and the elastic body displacement detecting means 36 as in the first embodiment, and the load is controlled to measure the surface shape. To do. The stage 41 is moved to deal with a change in shape that exceeds the stroke of the moving body 33.

This embodiment, which is constructed in this way, also exhibits the same effects as the first, second and third embodiments.

Besides the structures shown in the first to third embodiments, the load detecting elastic body is a single leaf spring or the like, and the moving body is a stage using a ball screw as a rolling bearing. Various forms such as

As described above, it is necessary to lower the measurement load in order to reduce damage to the surface to be measured, but it has a sensitivity of the order of nN to μN and is applied to a shape measuring device. Although a load cell that is easy to find has not been found in the past, it is possible to detect the load with high sensitivity by converting the load into the deformation amount of the elastic body like STM and AFM. The elastic body that detects this load must be attachable to the stylus or integrated with the stylus, but the elastic body itself must be miniaturized from the viewpoint of weight reduction. In the present embodiment, it can be realized by manufacturing a parallel spring integrated by wire cutting or by processing a thin leaf spring into a predetermined size and shape by etching. Further, from the viewpoint of highly sensitive load detection, the elastic body must be a weak spring having a spring constant of 1000 N / m or less, but it can be applied within the current range of processing technology by wire cutting or etching.

In order to follow the shape of the surface to be measured with a constant load at a high speed, the load control is also required to have high responsiveness. This can be dealt with by mounting an elastic body for load detection on a moving body having a good response in the load control direction. This moving body is, for example, a parallel spring stage driven by a highly responsive actuator such as a piezoelectric element or a linear motor driven stage guided by an aerostatic bearing. Due to the miniaturization of the elastic body and the miniaturization of the moving body, the mass of the entire moving section is kept to a light weight of about several 100 g, and considering the rigidity of an actuator represented by a piezoelectric element, several hundred Hz to 1 Hz.
A moving body having a resonance frequency of kHz can be constructed.

In order to convert the measured load into the deformation amount of the elastic body, it is necessary to detect the displacement amount of the elastic body itself mounted on the moving body. In this embodiment, the displacement amount of both the elastic body and the moving body is monitored from a member serving as a reference of the movement of the moving body, for example, the moving body mounting member. At this time, the displacement amount of the elastic body itself corresponds to the difference between the displacement amounts of the two as viewed from the moving body mounting portion. If the spring constant of the elastic body is known in advance, the displacement amount of the elastic body corresponding to the set load can be known, and the moving body is driven so that the difference between this displacement amount and the displacement amount of the elastic body and the moving body becomes equal. This makes it possible to set the load. Once the load is set, the load control state is entered. The elastic body is controlled to drive the moving body so as to maintain a constant displacement amount, that is, to maintain a set load, and follows the surface shape to be measured. During this time,
The amount of change in the amount of displacement of the elastic body viewed from the moving body mounting portion is equal to the shape of the surface to be measured. The load control mechanism according to the present invention can measure the shape even within the moving range of the moving body even by itself.
At this time, the shape data matches the output of the elastic body displacement detection means.

Furthermore, by providing a stage as a holding table on which either the load control mechanism or the object to be measured is mounted separately from the load control mechanism as the entire structure of the apparatus, the measurement range can be expanded. When a shape change occurs that exceeds the movement range of the load control mechanism, the measurement range can be expanded to the movement distance of the stage by absorbing the change in the stroke on the stage side. If the design shape is known, the stage is driven according to the design shape of the object to be measured, and the shape including the error component is made to follow the load control with high response, that is, the low frequency component of the surface to be measured on the stage side. And the high-frequency component is made to follow the load control mechanism to perform measurement. In this way, the load of function control and load of measurement is distributed, and high-speed measurement is possible by the coordinated operation of the load control mechanism and the stage. At this time, the shape data is obtained by adding the displacement of the stage and the displacement of the elastic body.

According to the present invention, by disposing the displacement detecting means separately on each of the elastic body and the moving body, the weight of the moving portion can be reduced and a high speed response can be realized. Further, by disposing the displacement detecting means in a separated manner as in the present invention, the flexibility of the shapes of the elastic body and the moving body is increased, and the stylus portion can be designed according to the application.

[0044]

As described above, the present invention has the following effects.

By disposing the displacement detecting means in the load control mechanism away from the elastic body and the moving body to reduce the weight of the load control mechanism and to provide the moving body with high responsiveness,
High-speed load control is possible and the ability to follow shape changes is improved.

In addition, the load control mechanism and the holding table cooperate with each other to follow a high spatial frequency component by high-speed scanning and to expand the measurement range by the control similar to the coarse / fine movement interlocking.

Further, by arranging the displacement detecting means away from the elastic body and the moving body, the flexibility of designing the elastic body, the moving body and the stylus of the load control mechanism is widened, and a form suitable for the object to be measured can be selected.

[Brief description of drawings]

FIG. 1 is a perspective view showing the features of the main configuration of a first embodiment of a surface profile measuring apparatus of the present invention.

FIG. 2 is a side view of the first embodiment of the surface profile measuring apparatus of the present invention.

FIG. 3 is a flowchart showing the operation of the first embodiment by the controller of the surface profile measuring apparatus of the present invention.

FIG. 4 is a schematic diagram showing a load control state during measurement scanning in the surface profile measuring apparatus of the present invention.

FIG. 5 is a perspective view showing a second embodiment of the main configuration of the surface profile measuring apparatus of the present invention.

FIG. 6 is a front view of a second embodiment of the surface profile measuring apparatus of the present invention.

FIG. 7 is a perspective view showing a third embodiment of the main configuration of the surface profile measuring apparatus of the present invention.

FIG. 8 is a partial cross-sectional perspective view showing the configuration of the measuring head of the fourth embodiment of the surface profile measuring apparatus of the present invention.

FIG. 9 is a perspective view showing a fourth embodiment of the surface profile measuring apparatus of the present invention.

[Explanation of symbols]

1, 11, 21, 31 Stylus 2, 32 Parallel spring 3, 13, 23, 33 Moving body 4, 34 Frame 5, 15, 35 Actuator 6, 16, 27, 36 Elastic body displacement detecting means 7, 17, 28a , 28b, 37 Moving body displacement detecting means 8, 18, 41 Stage 9, 19, 40 Object to be measured 12, 22a, 22b Thin leaf spring 14 Moving body mounting guide section 20,43 Device body 24a, 24b Moving body guide section 25 Coil Part 26 Yoke Part 38 Base 39 Measuring Head 42 Stage Slider

Claims (2)

[Claims] 1. A surface shape measuring apparatus for contact-scanning a surface to be measured of a measured object with a stylus to measure a surface shape based on a displacement amount of the surface to be measured. A moving body having a high responsivity in a direction facing the surface to be measured and being capable of minute movement, and being fixed to the moving body, with its tip facing the surface to be measured. And a load control mechanism configured by an elastic body that is displaceable with respect to the surface to be measured and that is attachable or integrally provided, and the elastic body and the movable body are separately arranged. Displacement detecting means for detecting each displacement amount of the elastic body and the moving body, and a control device for controlling the load control mechanism according to a detection result by the displacement detecting means, wherein the control device is Due to the movement of the moving body, A load is applied up to a set load while the stylus is in contact with the surface so that the difference between the displacement amount of the movable body and the displacement amount of the elastic body is always equal to the displacement amount corresponding to the set load. A surface shape measuring device characterized by controlling the position of the. 2. A holding base on which one of a measurement object and a load control mechanism is mounted and which is capable of moving opposite to the measurement object or the load control mechanism. If it exceeds, the holding table is moved and the holding is performed together with the position control of the moving body so that the difference between the displacement of the moving body and the displacement of the elastic body is always equal to the displacement corresponding to the set load. The surface shape measuring apparatus according to claim 1, wherein the position of the table is controlled.