Nanometer displacement measuring equipment

Abstract

The utility model discloses a nanometer displacement measuring device which comprises a measuring casing and a test piece, one end of the measuring casing is provided with a grating, the inner wall of the measuring casing beside the grating is provided with a reflector, one side of the reflector is sequentially provided with an interference field, an optical amplification imaging system and a phase plate, one end of the reflector is provided with an image sensor, and the image sensor is connected with the measuring casing. The grating is arranged on the inner wall of the measuring casing, the image sensor is arranged on the inner wall of the measuring casing, a reflecting mirror is arranged on the inner wall, beside the grating, of the measuring casing, and an interference field, an optical amplification imaging system and a phase plate are further sequentially arranged on one side of the reflecting mirror, and the reflecting mirror, the interference field, the optical amplification imaging system, the phase plate and the image sensor are sequentially arranged on the inner wall, beside the grating, of the measuring casing. The phase difference of a transparent object is converted into the intensity difference, so that the contrast difference is highlighted, meanwhile, high-precision measurement is performed by utilizing the interference principle, the tiny difference of the surface height of a sample can be accurately measured, the displacement resolution below 1 nanometer can be realized, the debugging is simple, and the stability is good.

Description

Technical Field

[0001] This utility model relates to the field of displacement measurement equipment technology, specifically a nanometer displacement measurement device. Background Technology

[0002] High-precision nanoscale displacement measurement has important applications in ultra-high precision machining, microelectronics manufacturing, and other ultra-high precision testing and measurement technologies. Nanoscale displacement measurement generally employs capacitive sensor technology and dual-frequency laser measurement technology. However, capacitive sensors have a relatively small measurement range and are easily affected by external interference and distributed parameters; while dual-frequency laser measurement technology requires laser frequency modulation, resulting in a complex, bulky, and costly system. Furthermore, conventional optical measurement techniques, such as laser coherent measurement, are limited by the optical diffraction limit and are subject to systematic errors.

[0003] A prior art patent application (application number 202210216638.3) describes a nanoscale displacement measurement method based on optical imaging sensing. The device includes a stripe optical element, a coaxial illumination source, a beam-splitting optical element, an optical magnification imaging unit, and an optical pattern / image sensor. Its displacement resolution is no longer limited by the optical diffraction limit, enabling displacement detection at the nanometer scale. The micrometer-scale stripes are easy to fabricate, low in cost, and have virtually unlimited measurement range. The purpose of this invention is to provide a simpler, lower-cost nanoscale displacement measurement technique with virtually unlimited measurement range. However, it is difficult to achieve displacement resolution below 1 nanometer, and the debugging is complex with poor stability. Utility Model Content

[0004] The purpose of this invention is to provide a nanometer displacement measurement device to solve the problems of existing technologies that are difficult to achieve displacement resolution below 1 nanometer, and that are complex to debug and have poor stability.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a nanometer displacement measuring device, comprising a measuring housing and a test piece, wherein the lower side of the measuring housing is mounted on a base plate via a lower support plate, a grating is provided at one end of the measuring housing, a reflector is provided on the inner wall of the measuring housing next to the grating, and an interference field, an optical magnification imaging system and a phase plate are sequentially provided on one side of the reflector, and an image sensor is provided at the other end of the measuring housing, and the test piece is mounted on one side of the grating via a stand.

[0006] Furthermore, two reflectors are symmetrically arranged inside one end of the measuring housing.

[0007] Furthermore, the optical magnification imaging system includes a first magnifying imaging mirror and a second magnifying imaging mirror, and the first magnifying imaging mirror and the second magnifying imaging mirror are disposed on both sides of the phase plate.

[0008] Furthermore, the support frame includes a mounting plate disposed on the upper side of one end of the base plate. A lifting bracket and a lifting plate are provided in the lower support plate on the upper side of the mounting plate through a first lead screw thread. A middle support plate is provided on the upper part of the lifting plate, and a first slider is provided inside the middle support plate through a second lead screw. An upper support is provided on the upper side of the first slider, and a second slider is provided on the upper side of the upper support through a third lead screw. The test piece is fixedly disposed on one side of the second slider.

[0009] Furthermore, the lower end of the first lead screw is connected to an adjusting rod via a gear set, and one end of the adjusting rod is provided with an adjusting handle.

[0010] Furthermore, the included angle between the second lead screw and the third lead screw is ninety degrees, and both the second lead screw and the third lead screw are provided with an adjusting nut at one end.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] This invention features a measuring housing with a mirror, an interference field, an optical magnification imaging system, a phase plate, and an image sensor arranged sequentially on the inner wall of the housing next to the grating. By utilizing the characteristics of the phase plate, the phase difference of a transparent object is converted into an intensity difference, thereby highlighting the contrast difference. At the same time, high-precision measurement is performed using the interference principle, which can accurately measure minute differences in the height of the sample surface to achieve a displacement resolution of less than 1 nanometer. Moreover, it is simple to adjust and has good stability.

[0013] In this invention, the test piece is mounted on one side of the grating via a support frame. The support frame includes a mounting plate mounted on the upper side of one end of the base plate. A lifting bracket and a lifting plate are threaded onto the lower support plate on the upper side of the mounting plate via a first lead screw. A middle support plate is located on the upper part of the lifting plate, and a first slider is located inside the middle support plate via a second lead screw. An upper support is located on the upper side of the first slider, and a second slider is located on the upper side of the upper support via a third lead screw. The test piece is fixedly mounted on one side of the second slider, so that the lifting plate can be raised and lowered by rotating the first lead screw, thereby adjusting the height of the test piece. At the same time, the second and third lead screws can drive the lateral movement of the test piece for adjustment, thereby meeting the testing and processing needs of the test piece in different positions. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0016] Figure 2 This is a first-view structural diagram of the support frame of this utility model.

[0017] Figure 3 This is a schematic diagram of the second-view structure of the support frame of this utility model;

[0018] Figure 4 This is the overall schematic diagram of the present invention.

[0019] In the diagram: 1. Base plate; 2. Measuring housing; 3. Lower support plate; 4. Mounting plate; 5. First slider; 6. Lifting plate; 7. Lifting bracket; 8. Middle support plate; 9. Upper support; 10. Third lead screw; 11. Second slider; 12. Test piece; 13. First lead screw; 14. Gear set; 15. Adjusting rod; 16. Adjusting handle; 17. Grating; 18. Reflector; 19. Interference field; 20. First magnifying imaging mirror; 21. Phase plate; 22. Second magnifying imaging mirror; 23. Image sensor; 24. Second lead screw. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4 In this embodiment of the present invention, a nanometer displacement measuring device includes a measuring housing 2 and a test piece 12. The lower side of the measuring housing 2 is mounted on a base plate 1 via a lower support plate 3. A grating 17 is provided at one end of the measuring housing 2, and a reflector 18 is provided on the inner wall of the measuring housing 2 next to the grating 17. An interference field 19, an optical magnification imaging system, and a phase plate 21 are also provided sequentially on one side of the reflector 18. The phase plate 21 is used to convert the phase difference of a transparent object into an intensity difference, thereby highlighting the contrast difference. An image sensor 23 is also provided at the other end of the measuring housing 2. Two reflectors 18 are symmetrically arranged inside one end of the measuring housing 2. The optical magnification imaging system includes a first magnifying imaging mirror 20 and a second magnifying imaging mirror 22, which are arranged on both sides of the phase plate 21. At the same time, the interference principle of the interference field 19 is used to perform high-precision measurement, which can accurately measure the small difference in the height of the sample surface to achieve a displacement resolution of less than 1 nanometer. Moreover, it is simple to debug and has good stability.

[0022] like Figure 1 , Figure 2 and Figure 3As shown, in order to meet the testing needs of test pieces 12 at different positions, test pieces 12 are also mounted on one side of the grating 17 via a support frame. The support frame includes a mounting plate 4 mounted on the upper side of one end of the base plate 1. A lifting bracket 7 and a lifting plate 6 are threaded onto the lower support plate 5 on the upper side of the mounting plate 4 via a first lead screw 13. A middle support plate 8 is provided on the upper part of the lifting plate 6, and a first slider 5 is provided inside the middle support plate 8 via a second lead screw 24. An upper support 9 is provided on the upper side of the first slider 5, and a second slider 11 is provided on the upper side of the upper support 9 via a third lead screw 10. The test piece 12 is fixedly mounted on one side of the second slider 11. The included angle between the second lead screw 24 and the third lead screw 10 is 90 degrees, and both the second lead screw 24 and the third lead screw 10 are provided with adjusting nuts at one end. This allows the lifting plate 6 to be raised and lowered by rotating the first lead screw 13, thereby adjusting the working height of the test piece 12. At the same time, the second lead screw 24 and the third lead screw 10 can drive the lateral movement adjustment of the test piece 12, thereby meeting the testing and use of the test piece 12 in different positions and improving the testing efficiency.

[0023] like Figure 2 and Figure 3 As shown, in order to adjust or lock the adjusting rod 15, an adjusting rod 15 is also connected to the lower end of the first lead screw 13 via a gear set 14. One end of the adjusting rod 15 is provided with an adjusting handle 16 and a locking bolt, which facilitates locking the adjusting rod 15.

[0024] The working principle and usage process of this utility model are as follows: During use, the reflector 18, interference field 19, optical magnification imaging system, phase plate 21 and image sensor 23 are sequentially arranged on the inner wall of the measuring housing 2 next to the grating 17. By utilizing the characteristics of the phase plate 21, the phase difference of the transparent object is converted into an intensity difference, thereby highlighting the contrast difference. At the same time, the interference principle of the interference field 19 is used to perform high-precision measurement, which can accurately measure the small difference in the height of the sample surface to achieve a displacement resolution of less than 1 nanometer. Moreover, the adjustment is simple and the stability is good.

[0025] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A nanometre displacement measuring apparatus comprising a measuring housing (2) and a test piece (12), characterised in that: The measuring machine shell (2) is installed on the bottom plate (1) through the lower support plate (3) on the lower side, one end of the measuring machine shell (2) is provided with a grating (17), the inner wall of the measuring machine shell (2) beside the grating (17) is provided with a mirror (18), one side of the mirror (18) is further provided with an interference field (19), an optical amplification imaging system and a phase plate (21) in sequence, the other end of the measuring machine shell (2) is further provided with an image sensor (23), and the test piece (12) is arranged on one side of the grating (17) through a stand.

2. A nanometre displacement measuring apparatus according to claim 1, characterised in that: The mirror (18) is symmetrically provided with two in the measuring machine shell (2) on one end.

3. A nanometre displacement measuring apparatus according to claim 1, characterised in that: The optical amplification imaging system comprises a first amplification imaging mirror (20) and a second amplification imaging mirror (22), and the first amplification imaging mirror (20) and the second amplification imaging mirror (22) are arranged on both sides of the phase plate (21).

4. The nanometer displacement measuring apparatus according to claim 1, wherein: The stand comprises a mounting plate (4) arranged on the upper side of one end of the bottom plate (1), a lifting support (7) and a lifting plate (6) are threadedly arranged on the upper side of the mounting plate (4) through a first lead screw (13), a middle support plate (8) is arranged on the upper portion of the lifting plate (6), a second lead screw (24) is arranged in the middle support plate (8), and a first sliding block (5) is arranged on the second lead screw (24), an upper support (9) is arranged on the upper side of the first sliding block (5), a second sliding block (11) is arranged on the upper side of the upper support (9) through a third lead screw (10), and the test piece (12) is fixedly arranged on one side of the second sliding block (11).

5. A nanometre displacement measuring apparatus according to claim 4, characterised in that: The first lead screw (13) is connected with an adjusting rod (15) through a gear set (14) on the lower end, and the adjusting rod (15) is provided with an adjusting handle (16) on one end.

6. A nanometre displacement measuring apparatus according to claim 4, characterised in that: The included angle between the second lead screw (24) and the third lead screw (10) is ninety degrees, and the first lead screw (24) and the third lead screw (10) are provided with adjusting nuts on one end.

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