Precision test platform

Abstract

The invention relates to the technical field of test platforms, in particular to a precision test platform, which comprises a support assembly, a laser interferometer, a laser transmitter and a measuring mirror group, the measuring mirror group is provided with a first part and a second part, original laser emitted by the laser emitter is divided into two paths of light beams through the first part, one path of light beam is directly reflected back to the laser emitter by the first part, and the other path of light beam is reflected to the laser emitter after passing through the second part; and the two paths of light beams meet and interfere with each other at the laser transmitter. The interference phenomenon can be utilized to detect the moving precision of the five-axis automatic sample table in each direction. When a precision test in a linear or angular direction is carried out, a complete light and shade interference phenomenon can be generated every time the second part moves by a distance of a half laser wavelength or rotates by a preset angle, so that the precision can reach a nanometer level, and a high-precision positioning test is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of testing platforms, and in particular to a precision testing platform. Background Art

[0002] A scanning electron microscope is a type of electron microscope. The five-axis automatic sample stage is one of the standard features of a scanning electron microscope. The five-axis automatic sample stage can move in the X-axis, Y-axis, Z-axis, T-axis and R-axis. It is composed of multiple stepper motors, transmission screws, guide rails, turbines, etc. It has multi-dimensional and high-precision positioning characteristics. When viewing images with an electron microscope, the sample stage can be controlled to move to the specified position through the electron microscope software to complete the viewing work.

[0003] Currently, there is a lack of equipment for performing precision detection on the five-axis automatic sample stage in all directions. Summary of the invention

[0004] In view of this, the present invention provides a precision testing platform to solve the problem of precision detection of a five-axis automatic sample stage in all directions.

[0005] In a first aspect, the present invention provides an accuracy testing platform, the accuracy testing platform comprising:

[0006] A support assembly is provided with a test panel; the test panel is suitable for fixing a sample stage;

[0007] A laser interferometer, comprising a laser transmitter and a measuring mirror assembly; the measuring mirror assembly is used at least for positioning accuracy testing in a linear direction and a rotation angle direction;

[0008] The measuring mirror assembly is provided with a first part and a second part. When measuring, along the emission direction of the laser, the laser emitter, the first part and the second part are arranged in sequence, and the second part is arranged on the sample stage;

[0009] The original laser emitted by the laser transmitter is divided into two light beams through the first part, namely a first laser and a second laser. The first laser is directly reflected back to the laser transmitter by the first part, and the second laser first passes through the second part and then reflects the laser transmitter, so that the first laser and the second laser meet at the laser transmitter and generate interference.

[0010] Beneficial effect: The embodiment of the present invention can detect the moving accuracy of the five-axis automatic sample stage in all directions by setting a laser interferometer, using the interference phenomenon generated by the first laser and the second laser. When performing an accuracy test in the straight line direction, a complete light and dark interference phenomenon will be generated every time the second part moves half the laser wavelength, so the measurement distance is equal to the number of interference fringes multiplied by the laser half wavelength, so that the accuracy can reach the nanometer level, thereby realizing a high-precision positioning test in the straight line direction. When performing an accuracy test in the rotation angle direction, the second part and the first part can convert the change in angle into the change in distance, and then every time the second part rotates a certain angle, a complete light and dark interference phenomenon will also be generated. Therefore, the interference phenomenon can also be used to perform a high-precision positioning test on the rotation angle. Furthermore, when performing positioning tests in different directions, the positions of various parts of the laser interferometer can be flexibly adjusted, and the positioning distribution of each part is relatively simple, which is convenient for technicians to operate.

[0011] In an optional implementation, the measuring mirror group is a linear measuring mirror group; the linear measuring mirror group is used to perform positioning test on the accuracy of the straight line direction;

[0012] The linear measurement mirror group is provided with a splitting part and a reflecting part. When measuring the straight line direction, along the emission direction of the laser, the laser emitter, the splitting part and the reflecting part are arranged in sequence, and the reflecting part is arranged on the sample stage.

[0013] In an optional embodiment, the linear measurement mirror assembly includes:

[0014] A spectroscope assembly, arranged on the test panel or located above the sample stage;

[0015] A reflector assembly, arranged on the sample stage;

[0016] Along the emission direction of the laser, the laser emitter, the beam splitter assembly and the reflector assembly are arranged in sequence;

[0017] The original laser emitted by the laser transmitter is divided into the first laser and the second laser by the beam splitter assembly. The first laser is directly reflected back to the laser transmitter by the beam splitter assembly, and the second laser first passes through the reflector assembly and then reflects the laser transmitter.

[0018] In an optional embodiment, the beam splitter assembly includes a first beam splitter and a first corner reflector;

[0019] The original laser light emitted by the laser transmitter is divided into the first laser light and the second laser light by the first beam splitter, and the first laser light is directly reflected back to the laser transmitter by the first corner reflector.

[0020] In an optional embodiment, the reflector assembly includes a second corner-cone reflector; the original laser emitted by the laser emitter is divided into the first laser and the second laser by the first beam splitter, and the second laser first passes through the second corner-cone reflector and then reflects the laser emitter.

[0021] In an optional embodiment, the support assembly further includes:

[0022] A support platform, provided with the test panel;

[0023] A support frame, arranged on the test panel;

[0024] A support plate, arranged on a side of the support frame away from the test panel;

[0025] The test panel, the support frame and the support plate surround and form a test space suitable for accommodating the sample stage.

[0026] In an optional embodiment, the support assembly further includes:

[0027] A plurality of casters are evenly arranged at the bottom of the support platform.

[0028] In an optional embodiment, the accuracy testing platform further includes:

[0029] A measuring pad is movably arranged on the test panel; when the sample stage is tested in a vertical direction, the laser emitter is placed on the measuring pad, and the first part of the measuring mirror group is arranged on the end surface of the support plate close to the test panel.

[0030] In an optional implementation, the measuring mirror assembly is an angle measuring mirror assembly; the angle measuring mirror assembly is used to perform positioning test on the accuracy of the rotation angle direction;

[0031] The angle measuring mirror group is provided with an interference part and a reflection part. When measuring the rotation angle direction, the laser emitter, the interference part and the reflection part are arranged in sequence along the emission direction of the laser; the interference part is arranged on the test panel, and the reflection part is arranged on the sample stage.

[0032] In an optional implementation, the angle measurement lens assembly includes:

[0033] An angle interferometer assembly is arranged on the test panel;

[0034] A reflector assembly, arranged on the sample stage;

[0035] Along the emission direction of the laser, the laser emitter, the angle interferometer assembly and the reflector assembly are arranged in sequence;

[0036] The original laser emitted by the laser transmitter is divided into the third laser and the fourth laser by the angle interferometer assembly. The third laser is reflected back to the laser transmitter by the angle interferometer assembly and the reflector assembly, and the fourth laser first passes through the reflector assembly and then reflects the laser transmitter.

[0037] In an optional embodiment, the angle interferometer assembly includes a second beam splitter and a plane reflector;

[0038] The original laser emitted by the laser emitter is divided into the third laser and the fourth laser by the second beam splitter. The third laser is directly reflected by the plane mirror to the reflector assembly, then reflected by the reflector assembly to the plane mirror, then reflected by the plane mirror to the second beam splitter, and then reflected back to the laser emitter by the second beam splitter.

[0039] In an optional embodiment, the reflector assembly includes a third corner reflector and a fourth corner reflector;

[0040] The original laser light emitted by the laser emitter is divided into the third laser light and the fourth laser light by the second beam splitter, the third laser light is directly reflected by the plane reflector to the third corner reflector, then reflected by the third corner reflector to the plane reflector, then reflected by the plane reflector to the second beam splitter, and then reflected by the second beam splitter back to the laser emitter;

[0041] The fourth laser first passes through the fourth corner reflector and then reflects off the laser emitter.

[0042] In an optional embodiment, the accuracy testing platform further includes:

[0043] The posture sensor is arranged on the sample stage; the posture sensor is used to detect the rotation stroke of the sample stage in a vertical plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1It is a schematic diagram of the overall structure of an accuracy testing platform according to an embodiment of the present invention;

[0046] Figure 2 Schematic diagram of each moving axis of the sample stage in an embodiment of the present invention;

[0047] Figure 3 is a schematic diagram of a sample stage in an embodiment of the present invention;

[0048] Figure 4 is a schematic diagram of linear measurement in an embodiment of the present invention;

[0049] Figure 5 A schematic diagram of the equipment layout for linear measurement in an embodiment of the present invention;

[0050] Figure 6 It is an overall schematic diagram of linear measurement in an embodiment of the present invention;

[0051] Figure 7 is a schematic diagram of angle measurement in an embodiment of the present invention;

[0052] Figure 8 A schematic diagram of the equipment layout for angle measurement in an embodiment of the present invention;

[0053] Fig. 9 An overall schematic diagram of angle measurement in an embodiment of the present invention;

[0054] Fig.10 This is a schematic diagram of the equipment layout for measuring the angle of the sample stage on the T axis in an embodiment of the present invention;

[0055] Fig.11 It is an overall schematic diagram of the sample stage performing stroke measurement on the T-axis in an embodiment of the present invention.

[0056] Description of reference numerals:

[0057] 1. Support assembly; 11. Support platform; 12. Support frame; 13. Support plate; 14. Casters;

[0058] 2. Laser interferometer;

[0059] 21. Laser transmitter; 211. First laser; 212. Second laser; 213. Third laser; 214. Fourth laser;

[0060] 22, linear measurement mirror assembly; 221, beam splitter assembly; 2211, first beam splitter; 2212, first corner reflector; 222, reflector assembly; 2221, second corner reflector;

[0061] 23, angle measuring mirror assembly; 231, angle interferometer assembly; 2311, second beam splitter; 2312, plane reflector; 232, reflector assembly; 2321, third corner reflector; 2322, fourth corner reflector;

[0062] 3. Test panel; 31. Fixed block; 4. Sample stage; 41. Fixed axis; 5. Measuring pad; 6. Posture sensor; 7. Sample stage control box; 8. Computer host. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0064] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal communication of two components, it can be a wireless connection, or it can be a wired connection. For ordinary workers in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0067] A scanning electron microscope is a type of electron microscope. The five-axis automatic sample stage is one of the standard features of a scanning electron microscope. The five-axis automatic sample stage can move in the X-axis, Y-axis, Z-axis, T-axis and R-axis. It is composed of multiple stepper motors, transmission screws, guide rails, turbines, etc. It has multi-dimensional and high-precision positioning characteristics. When viewing images with an electron microscope, the sample stage can be controlled to move to the specified position through the electron microscope software to complete the viewing work.

[0068] It should be noted that the X-axis, Y-axis, and Z-axis move in a linear direction, the T-axis rotates along a vertical plane, and the R-axis rotates on a horizontal plane.

[0069] Currently, there is a lack of equipment for performing precision detection on the five-axis automatic sample stage in all directions.

[0070] In view of this, the present invention provides a precision testing platform to solve the problem of precision detection of a five-axis automatic sample stage in all directions.

[0071] Combine the following Figures 1 to 11 , describing an embodiment of the present invention.

[0072] According to an embodiment of the present invention, on the one hand, a precision testing platform is provided. The precision testing platform includes a supporting assembly 1 and a laser interferometer 2 .

[0073] Specifically, in the embodiment of the present invention, Figure 1 As shown, the support assembly 1 is provided with a test panel 3, and the test panel 3 is suitable for fixing the sample stage 4. For example, the method of fixing the sample stage 4 can be fixed by the reserved holes on the test panel 3 and the fixed protrusions reserved at the bottom of the sample stage 4, that is, the fixing can be completed by directly embedding the fixed protrusions into the reserved holes. It can also be fixed by installing a fixing block 31 on the test panel 3, the fixing block 31 is provided with a through hole, and the sample stage 4 is provided with a pair of fixed shafts 41, and the fixed shafts 41 can be directly inserted into the through holes for fixing. It can also be fixed by a buckle slot, the buckle can be set on one of the test panel 3 and the sample stage 4, and the slot can be set on the other of the test panel 3 and the sample stage 4. Of course, a variety of fixing methods can also be combined and set, so as to further improve the stability of the sample stage 4 during the test process.

[0074] Of course, this embodiment is only an example of the fixing method of the sample stage 4 and the test panel 3, and this embodiment does not limit this. Those skilled in the art can make changes according to actual conditions as long as the same technical effect can be achieved.

[0075] Further, in an embodiment of the present invention, if Figure 4 and Figure 7As shown, the laser interferometer 2 includes a laser emitter 21 and a measuring mirror group, and the measuring mirror group is used to perform positioning tests on the accuracy of the linear direction and the rotation angle direction at least. Figure 2 and Figure 3 As shown, the sample stage 4 is a five-axis automatic sample stage 4, which can move in the X-axis, Y-axis, Z-axis, T-axis and R-axis, wherein the X-axis, Y-axis and Z-axis are common three-dimensional coordinate axes, the X-axis, Y-axis and Z-axis move in a linear direction, the T-axis rotates along a vertical plane, and the R-axis rotates on a horizontal plane. Therefore, the measuring lens group can perform positioning tests on the accuracy of the X-axis, Y-axis and Z-axis in the linear direction, and can also perform positioning tests on the T-axis and R-axis in the rotation angle direction.

[0076] Further, in an embodiment of the present invention, the measuring mirror assembly is provided with a first part and a second part. When measuring, along the emission direction of the laser, the laser emitter 21, the first part and the second part are arranged in sequence, and the second part is arranged on the sample stage 4 and needs to move with the sample stage 4. The setting position of the first part can be adjusted according to the change of the actual measurement direction. For example, when measuring the X-axis and the Y-axis, the first part can be directly set on the test panel 3, and when measuring the Z-axis, the first part needs to be fixed above the sample stage 4 to ensure that the measurement can be performed normally.

[0077] In the actual working process, the first part of the measuring lens group needs to have a splitting function. The original laser emitted by the laser emitter 21 is divided into two beams through the first part, namely the first laser 211 and the second laser 212. The first laser 211 is directly reflected back to the laser emitter 21 by the first part, and the second laser 212 first passes through the second part and then reflects the laser emitter 21, so that the first laser 211 and the second laser 212 meet at the laser emitter 21 and interfere. Since the first laser 211 and the second laser 212 have the same frequency, the same vibration direction and a constant phase difference, the interference condition is met, so the positioning detection of the sample stage 4 can be performed through the interference phenomenon.

[0078] With such a configuration, the embodiment of the present invention can detect the moving accuracy of the five-axis automatic sample stage 4 in all directions by configuring the laser interferometer 2, using the interference phenomenon generated by the first laser 211 and the second laser 212. When performing the accuracy test in the straight line direction, a complete light and dark interference phenomenon will be generated every time the second part moves half the laser wavelength, so the measurement distance is equal to the number of interference fringes multiplied by the laser half wavelength, so that the accuracy can reach the nanometer level, thereby realizing a high-precision positioning test in the straight line direction. When performing the accuracy test in the rotation angle direction, the second part and the first part can convert the angle variable into a distance variable, and then every time the second part rotates a certain angle, a complete light and dark interference phenomenon will also be generated. Therefore, the interference phenomenon can also be used to perform a high-precision positioning test on the rotation angle. Further, when performing positioning tests in different directions, the positions of the various parts of the laser interferometer 2 can be flexibly adjusted, and the positioning distribution of each part is relatively simple, which is convenient for technicians to operate.

[0079] Furthermore, the laser interferometer 2 is used to test the sample stage 4, and the accuracy of the test parameters is ensured by an adjustable positioning and installation design. In addition, the sample stage 4 has an independent test position, which solves the problem that it needs to be installed on the electron microscope for testing. For the new sample stage 4, testing can be performed before the machine is installed, and quality inspection is no longer required for the machine. The overall scanning electron microscope debugging time is saved, and the debugging and delivery cycle is shortened. At the same time, the continuous positioning accuracy, repeated positioning accuracy, stroke, and gap measurement requirements can be completed for a single test platform, and the integration is high. Furthermore, the test platform occupies a small space and is easy to move. The overall structure distribution is relatively simple, and the operation is simple and easy to use.

[0080] Further, in an optional embodiment, as Figures 4 to 6 As shown, the measuring mirror group is a linear measuring mirror group 22; the linear measuring mirror group 22 is used to perform positioning test on the accuracy of the straight line direction.

[0081] The linear measurement mirror group 22 is provided with a splitting part and a reflecting part. When measuring the straight line direction, along the emission direction of the laser, the laser emitter 21, the splitting part and the reflecting part are arranged in sequence, and the reflecting part is arranged on the sample stage 4.

[0082] Further, in an optional embodiment, as Figure 4 As shown, the linear measurement mirror assembly 22 includes a beam splitter component 221 and a reflector component 222 .

[0083] Specifically, in the embodiment of the present invention, the spectroscope assembly 221 is arranged on the test panel 3, or is located above the sample stage 4. That is to say, the setting position of the spectroscope assembly 221 can be adjusted according to the change of the actual measurement direction. For example, when measuring the X-axis and the Y-axis, the spectroscope assembly 221 can be directly arranged on the test panel 3, and when measuring the Z-axis, the spectroscope assembly 221 needs to be fixed above the sample stage 4 to ensure that the measurement can be performed normally.

[0084] Furthermore, the reflector assembly 222 is disposed on the sample stage 4 and needs to move along with the sample stage 4 .

[0085] During the test, along the laser emission direction, the laser emitter 21, the beam splitter assembly 221 and the reflector assembly 222 are arranged in sequence. The original laser emitted by the laser emitter 21 is split into two beams by the beam splitter assembly 221, namely the first laser 211 and the second laser 212. The first laser 211 is directly reflected back to the laser emitter 21 by the beam splitter assembly 221, and the second laser 212 first passes through the reflector assembly 222 and then reflects the laser emitter 21.

[0086] Further, in an optional embodiment, as Figure 4 As shown, the beam splitter assembly 221 includes a first beam splitter 2211 and a first corner reflector 2212. The original laser light emitted by the laser emitter 21 is split into two beams by the first beam splitter 2211, namely the first laser light 211 and the second laser light 212. After the first laser light 211 is directly reflected by the first corner reflector 2212, it passes through the first beam splitter 2211 and is reflected back to the laser emitter 21 by the first beam splitter 2211.

[0087] Further, in an optional embodiment, as Figure 4 As shown, the reflector assembly 222 includes a second corner reflector 2221. The original laser light emitted by the laser emitter 21 is split into the first laser light 211 and the second laser light 212 by the first beam splitter 2211, and the second laser light 212 first passes through the second corner reflector 2221 and then reflects the laser emitter 21.

[0088] Further, in an optional embodiment, as Figure 1As shown, the support assembly 1 further includes a support table 11, a support frame 12 and a support plate 13. The test panel 3 is arranged on the support table 11, the support frame 12 is arranged on the test panel 3, and the support plate 13 is arranged on a side of the support frame 12 away from the test panel 3. The test panel 3, the support frame 12 and the support plate 13 surround and form a test space suitable for accommodating the sample table 4, that is, the test panel 3, the support frame 12 and the support plate 13 surround and form a frame structure.

[0089] Further, in an optional embodiment, as Figure 1 As shown, the support assembly 1 further includes a plurality of casters 14, and the casters 14 are evenly arranged at the bottom of the support platform 11, so that the technicians can move the precision test platform as a whole conveniently.

[0090] Further, in an optional embodiment, the precision testing platform further includes a sample stage control box 7 and a computer host 8. The sample stage control box 7 and the computer host 8 are both placed in the positions reserved by the support table 11.

[0091] Further, in an optional embodiment, as Figure 1 As shown, the precision test platform further includes a measuring pad 5, which is movably arranged on the test panel 3. When the sample stage 4 is tested in the vertical direction, that is, when the sample stage 4 is tested in the Z-axis direction, the laser emitter 21 is placed on the measuring pad 5, and the first part of the measuring mirror group, that is, the spectroscope assembly 221 of the measuring mirror group is arranged on the end surface of the support plate 13 close to the test panel 3.

[0092] Further, in an optional embodiment, as Figure 7 As shown, the measuring mirror group is an angle measuring mirror group 23, and the angle measuring mirror group 23 is used to perform positioning test on the accuracy of the rotation angle direction.

[0093] The angle measurement lens group 23 is provided with an interference part and a reflection part. When measuring the rotation angle direction, the laser emitter 21, the interference part and the reflection part are arranged in sequence along the emission direction of the laser. The interference part is arranged on the test panel 3, and the reflection part is arranged on the sample stage 4. When the sample stage 4 rotates, the reflection part is also driven to rotate. The reflection part and the interference part can jointly convert the angle variable into the distance variable, and then the sample stage 4 can be positioned and detected through the interference phenomenon.

[0094] Further, in an optional embodiment, as Figure 7 and Figure 8As shown, the angle measurement mirror assembly 23 includes an angle interferometer component 231 and a reflector component 232 .

[0095] Specifically, in the embodiment of the present invention, the angle interferometer assembly 231 is arranged on the test panel 3, and the reflector assembly 232 is arranged on the sample stage 4. Along the emission direction of the laser, the laser emitter 21, the angle interferometer assembly 231 and the reflector assembly 232 are arranged in sequence.

[0096] The original laser emitted by the laser emitter 21 is divided into two light beams by the angle interferometer assembly 231, namely the third laser 213 and the fourth laser 214. The third laser 213 is reflected back to the laser emitter 21 by the angle interferometer assembly 231 and the reflector assembly 232, and the fourth laser 214 first passes through the reflector assembly 232 and then reflects the laser emitter 21.

[0097] Further, in an optional embodiment, as Figure 7 As shown, the angle interferometer assembly 231 includes a second beam splitter 2311 and a plane reflector 2312 .

[0098] The original laser emitted by the laser emitter 21 is divided into two light beams by the second beam splitter 2311, namely the third laser 213 and the fourth laser 214. The third laser 213 is directly reflected by the plane mirror 2312 to the mirror assembly 232, and then reflected by the mirror assembly 232 to the plane mirror 2312, and then reflected by the plane mirror 2312 to the second beam splitter 2311, and then reflected back to the laser emitter 21 by the second beam splitter 2311.

[0099] Further, in an optional embodiment, as Figure 7 As shown, the reflector assembly 232 includes a third corner reflector 2321 and a fourth corner reflector 2322 .

[0100] The original laser light emitted by the laser emitter 21 is divided into the third laser light 213 and the fourth laser light 214 by the second beam splitter 2311. The third laser light 213 is directly reflected by the plane mirror 2312 to the third corner reflector 2321, and then reflected by the third corner reflector 2321 to the plane mirror 2312, and then reflected by the plane mirror 2312 to the second beam splitter 2311, and then reflected back to the laser emitter 21 by the second beam splitter 2311. The fourth laser light 214 first passes through the fourth corner reflector 2322 and then reflects the laser emitter 21.

[0101] Further, in an optional embodiment, as Figure 1 As shown, the precision testing platform further includes a posture sensor 6, which is arranged on the sample stage 4. The posture sensor 6 is used to detect the rotation stroke of the sample stage 4 in the vertical plane.

[0102] The following is a detailed description of the precision positioning test in the linear direction and the rotation angle direction.

[0103] When testing the accuracy of the X-axis, Y-axis, and Z-axis in the linear direction, you can test the continuous positioning accuracy, repeated positioning accuracy, stroke, and clearance. The following takes the X-axis as an example, and the specific situation is as follows:

[0104] Continuous positioning accuracy test: ① Select a point as a reference; ② Set the sample stage 4 to stay for a short period of time after each travel of a certain distance, record the measured value, and the difference between the measured value and the set value, and after multiple recordings, select the largest difference, which is the continuous positioning accuracy.

[0105] Repeat positioning accuracy test: ① Select a point as the reference; ② Set a positioning point that is not the current position, position to the positioning point from different positions multiple times, record the measured value, and the difference between the measured value and the set value. The maximum value of the difference between the measured value and the set value is the repeat positioning accuracy.

[0106] Stroke test: ① Move the sample stage 4 to one end along the X-axis, and use this position as the measurement reference; ② Move the sample stage 4 to the other end along the X-axis, and the measured distance is the stroke;

[0107] Gap amount: ① first move the sample stage 4 along the X-axis in one direction for a certain distance, drive the motor to rotate for at least one circle, and after stopping, measure the distance as a reference; ② continue to move the sample stage 4 along the X-axis in this direction for a certain distance and then stop; ③ move the sample stage 4 along the other direction of the X-axis by the same distance and then stop, and measure the difference between the current value and the reference value as the gap amount.

[0108] When testing the accuracy of the T-axis and R-axis in the rotation angle direction, you can test the continuous positioning accuracy and repeated positioning accuracy. The following takes the R-axis as an example, the specific situation is as follows:

[0109] Continuous positioning accuracy: ① Set the R axis at an angle, for example, the reflector assembly 232 can be perpendicular to the optical path within ±10°; ② Rotate the R axis and move continuously within the range of ±10°. Each time it moves, stay for a short time and record the difference between the measured value and the set value. After multiple records, take the maximum value.

[0110] Repeatability: ① Set the R axis at an angle, for example, the reflector assembly 232 can be perpendicular to the optical path within ±10°. ② Rotate the R axis, select a point within the range of ±10°, and move it to the positioning point from different positions multiple times. The maximum difference between the measured value and the set value is the repeatability.

[0111] For the travel of the T axis, the test steps are as follows:

[0112] ① Set the T axis at position 0, that is, the sample stage 4 is parallel to the test panel 3, and record the measured value of the attitude sensor 6;

[0113] ② Turn the T axis to one side direction limit and record the first measurement value of the attitude sensor 6;

[0114] ③ Rotate the T axis to the other side limit and record the second measured value of the attitude sensor 6;

[0115] ④ The stroke is the sum of the first measured value and the second measured value.

[0116] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A precision testing platform, characterized in that: include: A support assembly (1) is provided with a test panel (3); the test panel (3) is suitable for fixing a sample table (4); A laser interferometer (2) comprising a laser emitter (21) and a measuring mirror assembly; the measuring mirror assembly is used at least to perform positioning tests on the accuracy in a linear direction and a rotation angle direction; The measuring mirror assembly is provided with a first part and a second part. When measuring, along the emission direction of the laser, the laser emitter (21), the first part and the second part are arranged in sequence, and the second part is arranged on the sample stage (4); The original laser light emitted by the laser emitter (21) is divided into two light beams after passing through the first part, one of which is directly reflected back to the laser emitter (21) by the first part, and the other light beam first passes through the second part and then reflects back to the laser emitter (21), so that the two light beams meet at the laser emitter (21) and generate interference.

2. The accuracy testing platform according to claim 1, characterized in that: The measuring mirror group is a linear measuring mirror group (22); the linear measuring mirror group (22) is used to perform positioning test on the accuracy of a straight line direction; The linear measurement mirror group (22) is provided with a light splitting part and a light reflecting part. When measuring the straight line direction, along the emission direction of the laser, the laser emitter (21), the light splitting part and the light reflecting part are arranged in sequence, and the light reflecting part is arranged on the sample stage (4).

3. The accuracy testing platform according to claim 2, characterized in that: The linear measurement mirror assembly (22) comprises: A spectroscope assembly (221), arranged on the test panel (3), or located above the sample stage (4); A reflector assembly (222) is arranged on the sample stage (4); Along the emission direction of the laser, the laser emitter (21), the beam splitter assembly (221) and the reflector assembly (222) are arranged in sequence; The original laser light emitted by the laser emitter (21) is split into two light beams after passing through the beam splitter assembly (221), namely a first laser light (211) and a second laser light (212); the first laser light (211) is directly reflected back to the laser emitter (21) by the beam splitter assembly (221), and the second laser light (212) first passes through the reflector assembly (222) and then reflects back to the laser emitter (21).

4. The accuracy testing platform according to claim 3, characterized in that: The beam splitter assembly (221) comprises a first beam splitter (2211) and a first corner cube reflector (2212); The original laser light emitted by the laser emitter (21) is split into two light beams by the first beam splitter (2211), namely the first laser light (211) and the second laser light (212), and the first laser light (211) is directly reflected back to the laser emitter (21) by the first conic reflector (2212).

5. The accuracy testing platform according to claim 4, characterized in that: The reflector assembly (222) is a second corner-cone reflector (2221); the original laser light emitted by the laser emitter (21) is split into the first laser light (211) and the second laser light (212) by passing through the first beam splitter (2211); the second laser light (212) first passes through the second corner-cone reflector (2221) and then reflects off the laser emitter (21).

6. The accuracy testing platform according to any one of claims 1 to 5, characterized in that: The support assembly (1) further comprises: A support platform (11) provided with the test panel (3); A support frame (12) is arranged on the test panel (3); A support plate (13) arranged on a side of the support frame (12) away from the test panel (3); The test panel (3), the support frame (12) and the support plate (13) surround and form a test space suitable for accommodating the sample stage (4).

7. The accuracy testing platform according to claim 6, characterized in that: The support assembly (1) further comprises: A plurality of casters (14) are evenly arranged on the bottom of the support platform (11).

8. The accuracy testing platform according to claim 6, characterized in that: The precision testing platform also includes: A measuring pad (5) is movably arranged on the test panel (3); when the sample stage (4) is tested in a vertical direction, the laser emitter (21) is placed on the measuring pad (5), and the first part of the measuring mirror group is arranged on the end surface of the support plate (13) close to the test panel (3).

9. The accuracy testing platform according to claim 1, characterized in that: The measuring mirror group is an angle measuring mirror group (23); the angle measuring mirror group (23) is used to perform positioning test on the accuracy of the rotation angle direction; The angle measuring mirror group (23) is provided with an interference part and a reflection part. When measuring the rotation angle direction, along the emission direction of the laser, the laser emitter (21), the interference part and the reflection part are arranged in sequence; the interference part is arranged on the test panel (3), and the reflection part is arranged on the sample stage (4).

10. The accuracy testing platform according to claim 9, characterized in that: The angle measuring lens assembly (23) comprises: An angle interferometer assembly (231) is arranged on the test panel (3); A reflector assembly (232) is arranged on the sample stage (4); Along the emission direction of the laser, the laser emitter (21), the angle interferometer assembly (231) and the reflector assembly (232) are arranged in sequence; The original laser light emitted by the laser emitter (21) passes through the angle interferometer assembly (231) and is divided into two light beams, namely a third laser light (213) and a fourth laser light (214); the third laser light (213) passes through the angle interferometer assembly (231) and the reflector assembly (232) and is reflected back to the laser emitter (21); and the fourth laser light (214) passes through the reflector assembly (232) and is then reflected back to the laser emitter (21).

11. The accuracy testing platform according to claim 10, characterized in that: The angle interferometer assembly (231) comprises a second beam splitter (2311) and a plane reflector (2312); The original laser light emitted by the laser emitter (21) is split into two light beams by the second beam splitter (2311), namely the third laser light (213) and the fourth laser light (214); the third laser light (213) is directly reflected by the plane reflector (2312) to the reflector assembly (232), then reflected by the reflector assembly (232) to the plane reflector (2312), then reflected by the plane reflector (2312) to the second beam splitter (2311), and then reflected by the second beam splitter (2311) back to the laser emitter (21).

12. The accuracy testing platform according to claim 11, characterized in that: The reflector assembly (232) comprises a third corner reflector (2321) and a fourth corner reflector (2322); The original laser light emitted by the laser emitter (21) is split into the third laser light (213) and the fourth laser light (214) by the second beam splitter (2311); the third laser light (213) is directly reflected by the plane reflector (2312) to the third corner reflector (2321), then reflected by the third corner reflector (2321) to the plane reflector (2312), then reflected by the plane reflector (2312) to the second beam splitter (2311), and then reflected by the second beam splitter (2311) back to the laser emitter (21); The fourth laser (214) first passes through the fourth corner reflector (2322) and then reflects off the laser emitter (21).

13. The accuracy testing platform according to any one of claims 9 to 12, characterized in that: The precision testing platform also includes: A posture sensor (6) is arranged on the sample stage (4); the posture sensor (6) is used to detect the rotational travel of the sample stage (4) in a vertical plane.

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