Rotary displacement table for adjusting angle of double gratings and method for adjusting parallelism of grating pair

Abstract

The invention relates to a rotary displacement table for adjusting the angle of double gratings and a method for adjusting the parallelism of a grating pair, and the rotary displacement table comprises a micro-vibration displacement table located at the bottom, a pair of grating adjusting clamps which are arranged on the micro-vibration displacement table, have the same structure and are arranged in a back-to-back manner, and a light surface receiving screen located between the two grating adjusting clamps. The two grating adjusting clamps respectively comprise telescopic grating clamps fixed on respective corresponding grating three-axis adjusting devices, and the method for adjusting the grating pair to be parallel comprises the following steps of: adjusting the pitching, rolling and deflection angles of a standard grating A and a grating B to be measured which are respectively clamped by the two telescopic grating clamps; respective reflected light of the two gratings is made to be perpendicular to collimation line light formed by the line light source through the horizontal slit to complete grating face parallel adjustment, and respective diffracted light connecting lines of the two gratings are made to be parallel to collimation line light formed by the line light source through the horizontal slit to complete grating line parallel adjustment. The modular design is adopted, the structure is compact, and mounting and dismounting are convenient.

Description

Technical Field

[0001] The invention relates to a grating clamping and measuring device, and in particular discloses a rotary displacement stage for adjusting the angle of double gratings and a method for adjusting the parallelism of grating pairs, which are applied to the field of optical metrology calibration. Background Art

[0002] As a common high-precision measuring material, gratings are widely used in the field of precision measurement of physical quantities such as displacement, speed, and angle. With the development of optical technology, grating technology has put forward higher requirements in terms of high precision, stability, and measurement range. In grating spacing calibration, the application of dual grating systems has gradually increased. It is usually necessary to align the grating surface and grating lines of the dual grating to ensure measurement accuracy. In the process of dual grating spacing measurement, due to problems such as non-parallel grating surfaces and inaccurate angle control, it is easy to cause the cosine error to increase, thereby affecting the overall accuracy of the system.

[0003] The existing grating clamping device structures are quite diverse and extensive, but the adjustment and installation structures mostly need to be customized according to the size of the grating, and the clamping space cannot be flexibly adjusted. At the same time, due to structural limitations, the grating can usually only be adjusted in two degrees of freedom. In addition, since the existing adjustment device is only for the convenience of fixing the grating and adjusting in the same direction, it is impossible to make the grating have rotational freedom and precisely control the angle, resulting in the grating system usually needing to be disassembled and reinstalled when adjusting, which is very complicated and cumbersome.

[0004] Therefore, how to accurately and quickly adjust the parallelism between the grating surface and the grating lines becomes an important technical problem in the grating spacing calibration system. Summary of the invention

[0005] The purpose of the present invention is to solve the problems existing in the prior art, and to design a rotary translation stage for adjusting the angle of dual gratings and a method for adjusting the parallelism of grating pairs. By combining a telescopic clamp with a rotary angle control and a micro-vibration displacement technology, the precise adjustment of the grating surface and grating lines can be quickly achieved. The application principle is simple, the operation is convenient and intuitive, and the controllability is good. The flexibility of adjusting the parallelism of the grating pairs is improved, and the efficiency of grating alignment measurement in a high-precision angle-controlled optical measurement system is also improved.

[0006] The present invention is implemented as follows: a dual-grating angle adjustment rotary displacement stage and a method for adjusting the parallelism of a grating pair, wherein the dual-grating angle adjustment rotary displacement stage is characterized in that it comprises a micro-vibration displacement stage at the bottom, a pair of grating adjustment fixtures with the same structure and arranged back to back on the micro-vibration displacement stage, and a light receiving screen located between the two grating adjustment fixtures, wherein the two grating adjustment fixtures respectively comprise telescopic grating fixtures fixed on their respective corresponding grating three-axis adjustment devices, and are arranged on both sides of the micro-vibration displacement stage through their respective rotary angle control bases, wherein the telescopic grating fixtures adopt a structure with adjustable jaw spacing, and are installed on the grating three-axis adjustment device through a connecting piece, and the grating three-axis adjustment device is used to adjust the grating XY The invention discloses a micro-vibration displacement platform for carrying out angle adjustment in three-axis directions of X, Y and Z, and comprises an inner part and an outer part, wherein the inner part is used for installing a telescopic grating fixture, and the outer part is provided with three ball head knobs respectively used for adjusting the angle of the grating in three-axis directions of X, Y and Z. The rotary angle control base is provided with a rotating disk which drives the grating three-axis adjustment device and the telescopic grating fixture to rotate synchronously, and the micro-vibration displacement platform comprises a platform base provided with a mechanical vibration module and a mounting panel provided on the mechanical vibration module, and the mounting panel is used for installing the grating adjustment fixture and the glossy receiving screen, and the mid-perpendicular line of the glossy receiving screen coincides with the vertical mid-line of the line connecting the centers of the two grating rotary angle control bases, and the glossy receiving screen is located at an angle position where the two sides can receive the corresponding reflected light after the line light sources on both sides are reflected by the corresponding gratings.

[0007] The back connector of the telescopic grating clamp adopts a buckle cylinder, and the front side is connected to the buckle cylinder by an inverted "L"-shaped telescopic block and an "L"-shaped telescopic block that are oppositely cross-matched and spliced. The inverted "L"-shaped telescopic block and the "L"-shaped telescopic block are both fixedly connected by a vertical block and a horizontal block that intersect and connect front and back. The horizontal blocks of the two telescopic blocks constitute a clamping claw for clamping the grating. The back surfaces of the two telescopic blocks are respectively provided with telescopic block threaded holes, and the buckle cylinder is provided with waist-shaped holes for adjusting the telescopic blocks that match the positions and sizes of the threaded holes of the two telescopic blocks respectively. Hexagonal tension bolts are screwed into the threaded holes of the telescopic blocks through the waist-shaped holes to fix the two telescopic blocks respectively. The spacing between the clamping claws is adjusted by loosening the hexagonal tension bolts and moving up and down. The inner surface of the telescopic block used to clamp the grating is provided with a spring clamping bead, and the spring restoring elastic force of the spring clamping bead is used to apply pressure to the grating to fix the grating. The telescopic block threaded holes arranged on the back surfaces of the two telescopic blocks are arranged on the back of the vertical block, and the spring clamping beads are arranged on the horizontal block, wherein the inverted "L"-shaped telescopic block is provided with 0 to 2 spring clamping beads, and the "L"-shaped telescopic block is provided with 2 or more spring clamping beads.

[0008] The inner part is provided with an inner part fixture mounting hole for installing a telescopic grating fixture, the outer part is provided with an outer part circular through hole matching the size of the buckle cylinder of the telescopic grating fixture, the embedded structure on the buckle cylinder provided on the telescopic grating fixture is embedded and spliced ​​with the inner part fixture mounting hole, the two shapes and structures are completely matched, the diameter of the circular through hole of the outer part is larger than the buckle cylinder, ensuring that the grating three-axis adjustment device has sufficient space for three-degree-of-freedom adjustment in the XYZ three-axis directions, the back surfaces of the vertical blocks of the two telescopic blocks are close to the front surface of the inner part, the inner part and the outer part are connected by a hook spring and fixed on both sides with short pins, the upper right corner and the lower left corner of the inner part and the outer part are both provided with a cross slot, the center of the cross slot is provided with a circular through hole for the hook spring to pass through, the ball head knob for adjusting the angle of the grating XYZ three-axis direction is respectively arranged on the left side of the top surface of the outer part, the middle side of the back surface and the right protruding part, and the bottom of the outer part is provided with a splicing column connected to the rotating angle control base below. The ball head knob comprises a knob, a threaded column and a ball head connected in sequence, a threaded line is provided in the middle position of the threaded column, the knob and the threaded column are connected and fixed by a cross pin, the ball head of the ball head knob passes through a circular threaded hole provided on the surface of the outer component and penetrates into an elliptical groove provided at a corresponding position of the inner component, and is tangent to three semicircular pads provided in the groove, the semicircular pads are used to cooperate with the ball head knob to change the relative position of the inner component and the outer component when adjusting the three-axis direction, the ball head knob on the middle side of the back surface of the outer component controls the inner component to drive the grating to adjust the pitch angle along the X-axis through the stretching of the hook spring, the top ball head knob controls the grating to adjust the roll angle along the Y-axis, and the protruding ball head knob on the right side controls the grating to adjust the yaw angle along the Z-axis.

[0009] The rotary angle control base is divided into a three-layer structure of a fixed disc, a rotating disc and a bottom support seat. A splicing groove is provided at the center of the upper surface of the fixed disc, and a splicing cylinder is provided at the center position of the splicing groove. The splicing cylinder at the bottom of the outer component is provided with an insertion hole matching the diameter of the splicing cylinder. The outer diameter of the splicing cylinder matches the aperture of the splicing groove. The grating three-axis adjustment device is connected to the rotary angle control base by inserting the splicing cylinder into the splicing cylinder, and the splicing cylinder is inserted into the splicing groove. A through hole is opened on the side wall of the fixed disc body, and the through hole penetrates the splicing cylinder in the direction of the circular surface diameter of the fixed disc. At the same time, a through hole is also provided at the corresponding position on the splicing cylinder perpendicular to the median line after penetrating cutting. After plugging in, use a hexagonal pin to insert it through and use a threaded knob to lock it at the other end. The four corners of the rotating disk are provided with disk threaded holes corresponding to the fixed disk, and the two are fixed with fastening screws. A circular through hole matching the diameter of the assembly hole at the center of the bottom surface of the fixed disk is opened at the center of the rotating disk, and a fixed cylinder matching the diameter of the circular through hole is provided at the center of the upper surface of the bottom support seat. Two or more elastic connecting beads are evenly distributed on the upper part of the side wall of the fixed cylinder, and a matching bead groove is correspondingly provided on the inner wall of the assembly hole set at the center of the bottom surface of the fixed disk. The fixed cylinder is inserted into the assembly hole at the center of the bottom surface of the fixed disk through the circular through hole of the rotating disk, and the elastic connecting bead is embedded in the bead groove to connect the bottom support seat, the fixed disk and the rotating disk into one. The outer circumferential surface of the rotating disc is provided with auxiliary angle scale lines and a handle, the outer circumferential surface of the bottom support seat is provided with 360° angle scale lines, the fixed disc and the rotating disc are relatively fixed, and the two discs and the grating three-axis adjustment device are driven to rotate synchronously by operating the handle.

[0010] The micro-vibration displacement stage is connected to the installation panel and the displacement stage base by connecting columns. Both sides of the displacement stage base are fixed to the work surface by fastening bolts. The bottom of the connecting column is fixed to the mechanical vibration module. The installation panel on the top of the connecting column is provided with installation holes corresponding to the threaded holes provided on the bottom surface of the rotary angle control base. The micro-vibration displacement stage is connected to the displacement stage drive system by a communication cable. The upper computer inputs the target parameters and sends out a vibration command. The vibration digital signal is converted into a voltage signal by a signal generator, which drives the micro-vibration displacement stage to drive the dual grating to vibrate continuously and synchronously along the vector direction during the measurement process.

[0011] The two sides of the smooth receiving screen are provided with completely identical grid-shaped engraved lines, a black circle center mark is provided at the center position of the diagonal line, and a telescopic rod is provided at the bottom of the smooth receiving screen.

[0012] The method for adjusting the parallelism of the grating pair is characterized by comprising adjusting the parallelism of the grating plane and adjusting the parallelism of the grating lines, and the specific steps are: Step 1: Use a telescopic grating fixture to clamp the calibration grating A and the grating to be measured B respectively, turn on the two line light sources, and the light is incident on the double grating through the horizontal collimated linear light formed by the horizontal slits. Control the handle of the rotating disk of the grating adjustment fixture holding the calibration grating A to drive the standard grating A to rotate until the reflected light of the standard grating A is observed on the light receiving screen. Adjust the X-axis pitch and Z-axis yaw ball head knobs of the grating three-axis adjustment device to make the reflected light parallel to the vertical scale of the grid-like scale on the light receiving screen, and record the angle scale value of the standard grating A displayed on the rotary angle control base at this time. According to the value, rotate the grating adjustment fixture holding the grating to be measured B to the corresponding angle value after increasing by 180°, observe the reflected light of the grating to be measured on the light receiving screen, adjust the X-axis pitch and Z-axis yaw ball head knobs of its grating three-axis adjustment device to make its reflected light also parallel to the vertical scale of the grid-like scale on the other side of the light receiving screen, and complete the parallel adjustment of the two grating surfaces; Step 2: Rotate the grating adjustment fixture that clamps the calibration grating A until the standard grating +1 order diffraction light and the standard grating +2 order diffraction light are observed on the light receiving screen, connect the points of the multi-order diffraction light on the light receiving screen into a diffraction light straight line, adjust the Y-axis rolling ball head knob of the corresponding grating adjustment fixture until the diffraction light straight line is parallel to the horizontal scale line of the grid-like scale line on the light receiving screen, then rotate the grating adjustment fixture that clamps the grating to be measured B until the standard grating +1 order diffraction light and the standard grating +2 order diffraction light are observed on the light receiving screen, connect the points of the multi-order diffraction light on the light receiving screen into a diffraction light straight line, adjust the Y-axis rolling ball head knob of the corresponding grating adjustment fixture so that the corresponding diffraction light straight line is also parallel to the horizontal scale line of the grid-like scale line on the light receiving screen, and complete the parallel adjustment of the two grating lines.

[0013] The beneficial effects of the present invention are as follows: the rotary translation stage for adjusting the angle of the dual gratings of the present invention adopts a modular design, and the adjustment of the grating angle position is achieved through the cooperation of a telescopic grating fixture, a grating three-axis adjustment device, a rotary angle control base and a micro-vibration translation stage, and the relative angle adjustment and control of the grating pair are achieved in combination with a light-surface receiving screen, and the parallelism of the grating surface is achieved by adjusting the reflected light of the dual gratings to be in a vertical state with the collimated line light formed by the horizontal slits on the light-surface receiving screen, and the parallelism of the grating lines is achieved by adjusting the diffracted light lines of the dual gratings to be in a parallel state with the collimated line light formed by the horizontal slits on the light-surface receiving screen.

[0014] The dual-grating angle adjustment rotary translation stage of the present invention has a compact structure, is easy to install and disassemble, and can flexibly adjust the clamping position according to gratings of different sizes, thereby improving the convenience of grating clamping and adjustment. Through the rotary angle control base and the multi-axial independent control design, it is ensured that the grating can achieve accurate positioning of pitch, roll, yaw adjustment and rotation angle in the three axes of X, Y, and Z. The rotary angle control base is equipped with scale lines and handles, making the adjustment of the grating rotation angle more intuitive and free. Combined with the calibration method of the optical receiving screen and the multi-order diffracted light, the diffracted light connection line of the grating can be quickly identified and accurately adjusted. The grating surface and grating line of the grating can be accurately aligned to the required angle and position, effectively improving the flexibility and reliability of the calibration of the grating spacing and the parallelism of the grating pair. Therefore, the dual-grating angle adjustment rotary translation stage of the present invention is not only suitable for the calibration requirements of the grating spacing, but can also be applied to other optical precision measurement devices that require multi-axial angle control, and has a wide range of application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a schematic diagram of the overall structure of the rotary translation stage for adjusting the double grating angle according to the present invention.

[0016] Figure 2 It is a structural schematic diagram of an inverted "L"-shaped telescopic block of the telescopic grating fixture in the present invention.

[0017] Figure 3 It is a structural schematic diagram of an "L"-shaped telescopic block of a telescopic grating fixture in the present invention.

[0018] Figure 4 It is a schematic diagram of the front structure of the buckle-type cylinder of the telescopic grating clamp in the present invention.

[0019] Figure 5 It is a schematic diagram of the back structure of the buckled cylinder of the telescopic grating clamp in the present invention.

[0020] Figure 6 It is a schematic diagram of the internal component structure of the grating three-axis adjustment device in the present invention.

[0021] Figure 7 It is a schematic diagram of the structure of the external components of the grating three-axis adjustment device in the present invention.

[0022] Figure 8 It is a schematic diagram of the fixed disc structure of the rotary angle control base in the present invention.

[0023] Fig. 9 yes Figure 8 Schematic diagram of the through hole structure opened on the fixed disk.

[0024] Fig.10It is a schematic diagram of the structure of the rotating disc of the rotary angle control base in the present invention.

[0025] Fig.11 It is a schematic diagram of the structure of the bottom support seat of the rotary angle control base in the present invention.

[0026] Fig.12 It is a structural schematic diagram of the micro-vibration displacement stage in the present invention.

[0027] Fig.13 It is a structural schematic diagram of the glossy receiving screen in the present invention.

[0028] Fig.14 It is a schematic diagram of the explosion structure of the ball knob in the present invention.

[0029] Fig.15 It is a schematic diagram of the optical path for adjusting the parallelism of the dual grating surfaces in the method for adjusting the parallelism of the grating pair described in the present invention.

[0030] Fig.16 It is a schematic diagram of the optical path for adjusting the parallelism of double grating lines in the method for adjusting the parallelism of grating pairs described in the present invention.

[0031] In the figure: 1. telescopic grating fixture; 2. grating three-axis adjustment device; 3. rotary angle control base; 4. micro-vibration displacement stage; 5. smooth receiving screen; 6. inverted "L"-shaped telescopic block; 7. "L"-shaped telescopic block; 8. spring clamping bead; 9. telescopic block threaded hole; 10. buckle cylinder; 11. hexagonal loose bolt; 12. embedded structure; 13. inner part; 14. outer part; 15. inner part fixture mounting hole; 16. outer part circular through hole; 17. cross slot; 18. hook spring; 19. short pin rod; 20. elliptical slot; 21. ball head knob; 22. semicircular pad; 23. Splicing cylinder; 24. Fixed disk; 25. Rotating disk; 26. Bottom support seat; 27. Splicing groove; 28. Splicing cylinder; 29. ​​Hexagonal pin rod; 30. Threaded knob; 31. Threaded hole of disk; 32. Fastening screw; 33. Elastic connection card bead; 34. Auxiliary angle scale line; 35. Handle; 36. Fixed cylinder; 37. 360° angle scale line; 38. Translation stage base; 39. Mechanical vibration module; 40. Connecting column; 41. Fastening bolt; 42. Mounting panel; 43. Mounting hole; 44. Smooth receiving screen; 45. Grid-shaped scale line; 46. Telescopic rod; 47, Linear light source; 48, Horizontal slit; 49, Incident light; 50, Reflected light; 51, Standard grating + 1st order diffracted light; 52, Standard grating + 2nd order diffracted light; 53, Grating to be measured + 1st order diffracted light; 54, Grating to be measured + 2nd order diffracted light; 211, knob; 212, cross latch; 213, threaded column; 214, ball head; A. Standard grating; B. Grating to be measured. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0033] According to the attached Figures 1 to 16 The present invention is a dual-grating angle adjustment rotary displacement stage and a method for adjusting the parallelism of a grating pair. The dual-grating angle adjustment rotary displacement stage adopts a modular design, and each module can be quickly disassembled and assembled into a whole. The dual-grating angle adjustment rotary displacement stage includes a micro-vibration displacement stage 4 at the bottom, a pair of grating adjustment fixtures with the same structure and back-to-back arranged on the micro-vibration displacement stage 4, and a light receiving screen 5 located between the two grating adjustment fixtures. The two grating adjustment fixtures respectively include a telescopic grating fixture 1 fixed on their respective corresponding grating three-axis adjustment devices 2, and are arranged on both sides of the micro-vibration displacement stage 4 through their respective rotary angle control bases 3.

[0034] In order to facilitate the clamping of gratings of different sizes, the telescopic grating clamp adopts a design with adjustable jaw spacing, and the jaws can be connected by elastic parts or adjustable auxiliary accessories. Figures 2 to 5 In this embodiment, the back connector of the telescopic grating fixture 1 adopts a buckle cylinder 10, and the front side is connected to the buckle cylinder 10 by an inverted "L"-shaped telescopic block 6 and an "L"-shaped telescopic block 7, which are oppositely cross-matched and spliced. The inverted "L"-shaped telescopic block 6 and the "L"-shaped telescopic block 7 are both fixedly connected by a vertical block and a horizontal block intersecting front and back. The horizontal blocks of the two telescopic blocks constitute the clamping claws for clamping the grating. The back surfaces of the two telescopic blocks are respectively provided with telescopic block threaded holes 9. In order to facilitate the alignment of the assembly position, the buckle The middle of the cylinder 10 is provided with a convex strip protruding to separate the left and right sides, and the left and right half surfaces are respectively provided with waist-shaped holes for adjusting the telescopic block, which match the position and size of the telescopic block threaded hole 9. The end of the hexagonal tension bolt 11 passes through the waist-shaped hole and is screwed into the telescopic block threaded hole 9 to fix the inverted "L"-shaped telescopic block 6 and the "L"-shaped telescopic block 7 on the buckle cylinder 10 respectively. Loosening the hexagonal tension bolt 11 can adjust the up and down movement according to the grating size until the telescopic grating fixture 1 can smoothly clamp the grating. The outer diagonal position of the buckle cylinder 10 is set to an embedded structure 12 for installation and matching with the grating three-axis adjustment device 2. The inner surface of the telescopic block for clamping the grating is provided with a spring clamping bead 8, which can extend and displace toward the inside of the telescopic block body. The semicircular smooth surface of the spring clamping bead 8 is convenient for installing and pushing the grating, and the spring restoring elastic force of the spring clamping bead 8 is used to apply pressure to the grating to keep the grating fixed.

[0035] As a technical optimization solution of the present invention, the telescopic block threaded holes 9 arranged on the back surfaces of the two telescopic blocks are arranged on the back of the vertical block, and the spring clamping beads 8 are arranged on the horizontal block, wherein the inverted "L"-shaped telescopic block 6 is provided with 0 to 2 spring clamping beads, and the "L"-shaped telescopic block 7 is provided with 2 or more spring clamping beads.

[0036] Reference Figures 6-7 With attached Fig.14 The grating three-axis adjustment device 2 is used to adjust the angle of the grating XYZ three-axis direction, and includes an inner part 13 and an outer part 14. The inner part 13 is provided with an inner part fixture installation hole 15, and the outer part 14 is provided with an outer part circular through hole 16 that matches the size of the buckle cylinder 10 of the telescopic grating fixture 1. The embedded structure 12 provided with the buckle cylinder 10 of the telescopic grating fixture 1 and the inner part fixture installation hole 15 can be embedded and spliced ​​until the back surface of the vertical block of the inverted "L"-shaped telescopic block 6 and the "L"-shaped telescopic block 7 is close to the front surface of the inner part 13, and the buckle cylinder 10 extends into the outer part circular through hole 16. The inner part 13 and the outer part 14 are both provided with a cross slot 17 at the upper right corner and the lower left corner, and the center of the cross slot 17 is provided with a circular through hole for the hook spring 18 to pass through. The inner part 13 and the outer part 14 are connected by the hook spring 18 and fixed by short pins 19 on both sides. The left side of the top surface of the inner part 13, the middle side of the back surface and the right side protruding part are all provided with an elliptical groove 20, and a circular threaded hole coaxial with the elliptical groove 20 is provided at the same position on the surface of the outer part 14. The ball head knob 21 passes through the circular threaded hole and penetrates into the elliptical groove 20, tangent to the three semicircular pads 22 in the groove. The semicircular pads 22 are used to cooperate with the ball head knob 21 to adjust the relative position of the inner part 13 and the outer part 14 when the three-axis direction is adjusted. The ball head knob 21 includes a knob 211, a threaded column 213 and a ball head 214 connected in sequence. The middle position of the threaded column 213 is provided with a thread line, and the knob 211 and the threaded column 213 are connected and fixed by a cross pin 212. The bottom of the outer part 14 is provided with a splicing column 23 connected to the rotating angle control base 3 below.

[0037] As a technical optimization solution of the present invention, the embedded structure 12 of the buckle cylinder 10 can be completely matched with the inner component fixture mounting hole 15, and the diameter of the circular through hole 16 of the outer component is slightly larger than the buckle cylinder 10, ensuring that the grating three-axis adjustment device 2 has sufficient space for three-degree-of-freedom adjustment in the XYZ three-axis directions. The ball head knob 21 on the middle side of the back surface of the outer component controls the inner component 13 to drive the grating to adjust the pitch angle along the X axis through the stretching of the hook spring 18, the top surface ball head knob 21 controls the grating to adjust the roll angle along the Y axis, and the right protruding ball head knob 21 controls the grating to adjust the yaw angle along the Z axis.

[0038] Reference Figures 8 to 11The rotary angle control base 3 is divided into a three-layer structure of a fixed disk 24, a rotating disk 25 and a bottom support seat 26. A splicing groove 27 is provided at the center of the upper surface of the fixed disk 24, and a splicing cylinder 28 is provided at the center position of the splicing groove 27. The splicing cylinder 23 at the bottom of the outer member 14 is provided with an insertion hole matching the diameter of the splicing cylinder 28. The outer diameter of the splicing cylinder 23 matches the aperture of the splicing groove 27. The grating three-axis adjustment device 2 is connected to the rotary angle control base 3 by inserting the splicing cylinder 28 into the splicing cylinder 23, and the splicing cylinder 23 is inserted into the splicing groove 27 at the same time. A through hole is provided on the side wall of the fixed disk 24 body, and the through hole penetrates the splicing cylinder 28 in the direction of the circular diameter of the fixed disk 24. At the same time, a through hole is also provided at the corresponding position perpendicular to the midline on the splicing cylinder 23 after penetrating cutting. After the grating three-axis adjustment device 2 is plugged into the fixed disk 24, a hexagonal pin rod 29 is inserted through it, and a threaded knob 30 is used to lock it at the other end. The rotating disc 25 has four corners with disc thread holes 31 corresponding to the fixed disc 24, and the two are fixed by fastening screws 32. A circular through hole matching the diameter of the assembly hole at the center of the bottom surface of the fixed disc 24 is opened at the center of the rotating disc 25. A fixed cylinder 36 matching the diameter of the circular through hole is provided at the center of the upper surface of the bottom support seat 26. Two or more elastic connection beads 33 are evenly distributed on the upper part of the side wall of the fixed cylinder 36. The inner wall of the assembly hole provided at the center of the bottom surface of the fixed disc 24 is provided with a matching bead groove. The fixed cylinder 36 is inserted into the assembly hole at the center of the bottom surface of the fixed disc 24 through the circular through hole of the rotating disc 25. The elastic connection bead 33 is embedded in the bead groove, and the bottom support seat 26, the fixed disc 24 and the rotating disc 25 are connected into one. The outer circumferential surface of the rotating disc 25 is provided with auxiliary angle scale lines 34 and a handle 35, and the outer circumferential surface of the bottom support seat 26 is provided with 360° angle scale lines 37.

[0039] As a technical optimization solution of the present invention, the fixed disk 24 and the rotating disk 25 are relatively fixed, and the two disks are driven to rotate synchronously with the grating three-axis adjustment device 2 by the operating handle 35. During rotation, the grating clamped on the telescopic grating clamp 1 can be accurately adjusted and positioned by observing the auxiliary angle scale line 34 corresponding to the 360° angle scale line 37.

[0040] Reference Figure 1 and attached Fig.12 The micro-vibration displacement stage 4 includes a mounting panel 42 and a displacement stage base 38 connected by a connecting column 40. Both sides of the displacement stage base 38 are fixed to the work surface by fastening bolts 41, and a mechanical vibration module 39 is embedded in the middle. The bottom of the connecting column 40 is fixed to the mechanical vibration module 39, and a mounting hole 43 corresponding to the threaded hole set on the bottom surface of the rotary angle control base 3 is provided on the mounting panel 42 at the top of the connecting column 40.

[0041] As a technical optimization solution of the present invention, the micro-vibration displacement stage 4 is connected to the displacement stage drive system by a communication cable. The host computer inputs the target parameters and issues a vibration command. The vibration digital signal is converted into a voltage signal through a signal generator to drive the micro-vibration displacement stage 4, so that the dual grating vibrates continuously and synchronously along the vector direction during the measurement process.

[0042] Reference Figure 1 With attached Fig.13 The glossy receiving screen 5 is fixed on the mounting panel 42, wherein the vertical line coincides with the vertical midline of the line connecting the centers of the two grating rotating angle control bases 3, and both sides of the glossy receiving screen 5 can receive the reflected light of the line light sources on each side after being reflected by the grating, and both sides of the glossy receiving screen 5 are provided with completely identical grid-shaped engraved lines 45, and a black center mark is provided at the center of the diagonal line, and a telescopic rod 46 is provided at the bottom of the glossy receiving screen 5, and the position height of the glossy receiving screen 5 is adjusted by the telescopic rod 14.

[0043] According to the attached Figures 1 to 16 In this embodiment, the specific assembly and adjustment process of the dual grating angle adjustment rotary translation stage is as follows: First, the inverted "L"-shaped telescopic block 6, the "L"-shaped telescopic block 7 and the buckle cylinder 10 are spliced, and the hexagonal loose bolt 11 is tightened to realize the assembly of the telescopic grating fixture 1. Then, the inner part 13 and the outer part 14 are connected by the hook spring 18 through the cross slot 17, and the short pin rod 19 is used to hook and fix the notch at one end of the inner part 13 and the notch at one end of the outer part 14, respectively. After aligning the elliptical grooves 20 and the circular threaded holes on the left side, the middle side of the back surface, and the right side of the protruding part of the top surface of the inner part 13 and the outer part 14, the ball head knob 21 is rotated and inserted into the three positions of the elliptical grooves 20 respectively, until the ball head 214 is tangent to the three semicircular pads 22, and the splicing of the grating three-axis adjustment device 2 is completed. Then, the embedded structure 12 of the buckle cylinder 10 of the telescopic grating fixture 1 is completely embedded in the fixture installation hole 15 of the inner part 13, and the assembly of the telescopic grating fixture 1 and the grating three-axis adjustment device 2 is completed. According to different grating sizes, the clamping size of the telescopic grating fixture 1 can be adjusted by moving the hexagonal tension bolt 11 up and down, and the pitch, roll and yaw angles of the grating three-axis degrees of freedom can be adjusted by rotating the ball head knob 21 on the grating three-axis adjustment device 2 corresponding to the three-axis direction.

[0044] Further, the fixed cylinder 36 on the bottom support seat 26 is inserted into the assembly hole of the fixed disk 24 through the circular through hole of the rotating disk 25, and the elastic connection bead 33 on the upper side wall of the fixed cylinder 36 is pressed against the bead groove on the inner wall of the assembly hole of the fixed disk 24, so that the rotary angle control base 3 remains stable and complete, and the fixed cylinder 36 does not affect the relative rotation of the rotating disk 25 and the fixed disk 24. When there is a need for disassembly, a separation force is applied to the bottom support seat 26, the rotating disk 25 and the fixed disk 24, and the elastic connection bead 33 is separated from the bead groove, and the three-layer structure of the rotary angle control base 3 can be disassembled in sequence. The circular hole of the splicing cylinder 23 on the bottom surface of the outer part 14 is aligned with the splicing groove 27 and the splicing cylinder 28, and then the through hole opened along the diameter of the disk is aligned with the cross section of the outer circle of the fixed disk 24 as the reference, and the hexagonal pin rod 29 is inserted from the incision at one end and pressed against, and the threaded line extending from the other end is locked with the threaded knob 30. The assembly of the rotary angle control base 3 and the grating three-axis adjustment device 2 is completed, and the rotating disk 25 drives the grating angle to be accurately positioned.

[0045] Furthermore, the two sides of the displacement stage base 38 of the micro-vibration displacement stage 4 are fixed to the work surface by fastening bolts 41, and the threaded holes on the bottom surface of the rotary angle control base 3 are aligned with the mounting holes 43 connected to the mounting panel 42. Then, the light receiving screen 5 is fixed to the mounting panel 42, ensuring that the mid-perpendicular line of the light receiving screen 5 coincides with the vertical mid-line of the line connecting the centers of the double-grating rotary angle control base 3, and at the same time, the light receiving screen 5 is at an angle position where the two sides can receive the corresponding reflected light after the line light source located on both sides is reflected by the corresponding grating, and the height of the light receiving screen 5 is adjusted by the telescopic rod 46. Finally, the assembly and fixation of all modules are completed.

[0046] Reference Fig.15 and attached Fig.16 The method for adjusting the parallelism of a grating pair using the rotary translation stage for double grating angle adjustment of the present invention includes parallel adjustment of the grating plane and the grating lines, which is achieved by adjusting the pitch, roll, and yaw angles of a standard grating A and a grating to be measured B respectively clamped by two telescopic grating clamps. The reflected light 50 of each of the two gratings is respectively perpendicular to the collimated line light formed by the line light source 47 through the horizontal slit 48, that is, the grating planes of the standard grating A and the grating to be measured B are parallel, and the connecting lines of the diffracted light of each of the two gratings are respectively parallel to the collimated line light formed by the line light source 47 through the horizontal slit 48, then the grating lines of the standard grating A and the grating lines of the grating to be measured B are parallel. During the adjustment process, the position of the light source remains fixed, and the direction of the incident light 49 also remains fixed.

[0047] The specific steps to adjust the parallelism of the grating pair are as follows: Step 1: Use the telescopic grating fixture 1 to clamp the calibration grating A and the grating to be measured B respectively, turn on the two line light sources 47, and the horizontal collimated linear light formed by the horizontal slits 48 is incident on the double gratings. Control the handle 35 of the rotating disk 25 of the grating adjustment fixture holding the calibration grating A to drive the standard grating A to rotate until the reflected light 50 of the standard grating A can be observed on the light receiving screen 5. Adjust the X-axis pitch and Z-axis yaw ball head knobs 21 of the grating three-axis adjustment device 2 so that the reflected light 50 is parallel to the light. The vertical scale line of the grid-like scale line 45 on the smooth receiving screen 5 is measured, and the angle scale value of the standard grating A displayed on the rotary angle control base 3 is recorded at this time. According to the value, the grating adjustment fixture holding the grating B to be measured is rotated to the corresponding angle value after increasing by 180°. The reflected light of the grating B to be measured is observed on the smooth receiving screen 5, and the X-axis pitch and Z-axis yaw ball head knobs of its grating three-axis adjustment device are adjusted to make its reflected light parallel to the vertical scale line of the grid-like scale line on the other side of the smooth receiving screen 5, so as to complete the parallelism of the two grating surfaces.

[0048] Step 2: Rotate the grating adjustment fixture that clamps the calibration grating A until the standard grating +1 order diffraction light 51 and the standard grating +2 order diffraction light 52 can be observed on the light surface receiving screen 5, connect the points of the multi-order diffraction light on the light surface receiving screen 5 into a diffraction light straight line, adjust the Y-axis rolling ball head 21 knob of the corresponding grating adjustment fixture until the diffraction light straight line is parallel to the horizontal scale line of the grid-like scale line 45 on the light surface receiving screen 5, then rotate the grating adjustment fixture that clamps the grating to be measured B until the grating +1 order diffraction light 53 and the grating +2 order diffraction light 54 to be measured can be observed on the light surface receiving screen 5, connect the points of the multi-order diffraction light on the light surface receiving screen 5 into a diffraction light straight line, adjust the Y-axis rolling ball head knob of the corresponding grating adjustment fixture so that the corresponding diffraction light straight line is also parallel to the horizontal scale line of the grid-like scale line on the light surface receiving screen 5, and complete the parallelism of the two grating lines.

[0049] The above embodiments are only used to clearly and completely describe the technical solutions of the present invention, rather than to limit the protection scope of the present invention. It should be understood that, for those skilled in the art, according to the idea of ​​the present invention, adaptive changes may be made in the specific implementation methods and application scopes, and all other implementation plans obtained by equivalent or equivalent substitution according to the solutions of the present invention shall belong to the protection scope of the present invention. The protection scope of the present invention shall be subject to the description of the claims of the present invention.

Claims

1. A rotary translation stage for adjusting the angle of a double grating, characterized in that: The invention comprises a micro-vibration displacement platform at the bottom, a pair of grating adjustment fixtures with the same structure and arranged back to back on the micro-vibration displacement platform, and a light receiving screen located between the two grating adjustment fixtures, wherein the two grating adjustment fixtures respectively comprise telescopic grating fixtures fixed on their respective corresponding grating three-axis adjustment devices, and are arranged on both sides of the micro-vibration displacement platform through their respective rotating angle control bases, the telescopic grating fixtures adopt a structure with adjustable jaw spacing, and are installed on the grating three-axis adjustment device through a connecting piece, and the grating three-axis adjustment device is used to adjust the angle of the grating XYZ three-axis direction, and comprises an inner part and an outer part, the inner part is used to install the telescopic grating fixture, and the inner part is used to install the telescopic grating fixture. The retractable grating fixture has three ball head knobs on the outer part for adjusting the angles of the grating XYZ three-axis directions respectively. The rotary angle control base is provided with a rotating disk that drives the grating three-axis adjustment device and the telescopic grating fixture to rotate synchronously. The micro-vibration displacement stage includes a platform base provided with a mechanical vibration module and a mounting panel provided on the mechanical vibration module. The mounting panel is used to install the grating adjustment fixture and the smooth receiving screen. The mid-perpendicular line of the smooth receiving screen coincides with the vertical mid-line of the line connecting the centers of the two grating rotary angle control bases, and is at an angle position where the two sides can respectively receive the corresponding reflected light after the line light sources on both sides are reflected by the corresponding gratings.

2. The dual grating angle adjustment rotary stage according to claim 1, characterized in that: The back connector of the telescopic grating clamp adopts a buckle cylinder, and the front side is connected to the buckle cylinder by an inverted "L"-shaped telescopic block and an "L"-shaped telescopic block, which are oppositely cross-matched and spliced. The inverted "L"-shaped telescopic block and the "L"-shaped telescopic block are both fixedly connected by a vertical block and a horizontal block intersecting front and back. The horizontal blocks of the two telescopic blocks constitute a clamping claw for clamping the grating. The back surfaces of the two telescopic blocks are respectively provided with telescopic block threaded holes, and the buckle cylinder is provided with waist-shaped holes for adjusting the telescopic blocks that match the positions and sizes of the threaded holes of the two telescopic blocks respectively. Hexagonal tension bolts are screwed into the threaded holes of the telescopic blocks through the waist-shaped holes to fix the two telescopic blocks respectively. The spacing between the clamping claws is adjusted by loosening the hexagonal tension bolts and moving up and down. The inner surface of the telescopic block used to clamp the grating is provided with a spring clamping bead, and the spring restoring elastic force of the spring clamping bead is used to apply pressure to the grating to fix the grating.

3. The dual grating angle adjustment rotary stage according to claim 2, characterized in that: The telescopic block threaded holes arranged on the back surfaces of the two telescopic blocks are arranged on the back of the vertical block, and the spring clamping beads are arranged on the horizontal block, wherein the inverted "L"-shaped telescopic block is provided with 0 to 2 spring clamping beads, and the "L"-shaped telescopic block is provided with 2 or more spring clamping beads.

4. The dual grating angle adjustment rotary stage according to claim 1, characterized in that: The inner part is provided with an inner part fixture mounting hole for installing a telescopic grating fixture, the outer part is provided with an outer part circular through hole matching the size of the buckle cylinder of the telescopic grating fixture, the embedded structure on the buckle cylinder provided on the telescopic grating fixture is embedded and spliced ​​with the inner part fixture mounting hole, the two shapes and structures are completely matched, the diameter of the circular through hole of the outer part is larger than the buckle cylinder, ensuring that the grating three-axis adjustment device has sufficient space for three-degree-of-freedom adjustment in the XYZ three-axis directions, the back surfaces of the vertical blocks of the two telescopic blocks are close to the front surface of the inner part, the inner part and the outer part are connected by a hook spring and fixed on both sides with short pins, the upper right corner and the lower left corner of the inner part and the outer part are both provided with a cross slot, the center of the cross slot is provided with a circular through hole for the hook spring to pass through, the ball head knob for adjusting the angle of the grating XYZ three-axis direction is respectively arranged on the left side of the top surface of the outer part, the middle side of the back surface and the right protruding part, and the bottom of the outer part is provided with a splicing column connected to the rotating angle control base below.

5. The dual grating angle adjustment rotary stage according to claim 4, characterized in that: The ball head knob comprises a knob, a threaded column and a ball head connected in sequence, a threaded line is provided in the middle position of the threaded column, the knob and the threaded column are connected and fixed by a cross pin, the ball head of the ball head knob passes through a circular threaded hole provided on the surface of the outer component and penetrates into an elliptical groove provided at a corresponding position of the inner component, and is tangent to three semicircular pads provided in the groove, the semicircular pads are used to cooperate with the ball head knob to change the relative position of the inner component and the outer component when adjusting the three-axis direction, the ball head knob on the middle side of the back surface of the outer component controls the inner component to drive the grating to adjust the pitch angle along the X-axis through the stretching of the hook spring, the top ball head knob controls the grating to adjust the roll angle along the Y-axis, and the protruding ball head knob on the right side controls the grating to adjust the yaw angle along the Z-axis.

6. The dual grating angle adjustment rotary stage according to claim 1, characterized in that: The rotary angle control base is divided into a three-layer structure of a fixed disc, a rotating disc and a bottom support seat. A splicing groove is provided at the center of the upper surface of the fixed disc, and a splicing cylinder is provided at the center position of the splicing groove. The splicing cylinder at the bottom of the outer component is provided with an insertion hole matching the diameter of the splicing cylinder. The outer diameter of the splicing cylinder matches the aperture of the splicing groove. The grating three-axis adjustment device is connected to the rotary angle control base by inserting the splicing cylinder into the splicing cylinder, and the splicing cylinder is inserted into the splicing groove. A through hole is opened on the side wall of the fixed disc body, and the through hole penetrates the splicing cylinder in the direction of the circular surface diameter of the fixed disc. At the same time, a through hole is also provided at the corresponding position on the splicing cylinder perpendicular to the median line after penetrating cutting. After plugging in, use a hexagonal pin to insert it through and use a threaded knob to lock it at the other end. The four corners of the rotating disk are provided with disk threaded holes corresponding to the fixed disk, and the two are fixed with fastening screws. A circular through hole matching the diameter of the assembly hole at the center of the bottom surface of the fixed disk is opened at the center of the rotating disk, and a fixed cylinder matching the diameter of the circular through hole is provided at the center of the upper surface of the bottom support seat. Two or more elastic connecting beads are evenly distributed on the upper part of the side wall of the fixed cylinder, and a matching bead groove is correspondingly provided on the inner wall of the assembly hole set at the center of the bottom surface of the fixed disk. The fixed cylinder is inserted into the assembly hole at the center of the bottom surface of the fixed disk through the circular through hole of the rotating disk, and the elastic connecting bead is embedded in the bead groove to connect the bottom support seat, the fixed disk and the rotating disk into one.

7. The dual grating angle adjustment rotary stage according to claim 6, characterized in that: The outer circumferential surface of the rotating disc is provided with auxiliary angle scale lines and a handle, the outer circumferential surface of the bottom support seat is provided with 360° angle scale lines, the fixed disc and the rotating disc are relatively fixed, and the two discs and the grating three-axis adjustment device are driven to rotate synchronously by operating the handle.

8. The dual grating angle adjustment rotary stage according to claim 1, characterized in that: The micro-vibration displacement platform is connected to the installation panel and the displacement platform base by connecting columns. Both sides of the displacement platform base are fixed to the work surface by fastening bolts. The bottom of the connecting column is fixed to the mechanical vibration module. The installation panel on the top of the connecting column is provided with installation holes corresponding to the threaded holes set on the bottom surface of the rotary angle control base. The micro-vibration displacement platform is connected to the displacement platform drive system by a communication cable. The upper computer inputs the target parameters and sends out a vibration command. The vibration digital signal is converted into a voltage signal by a signal generator to drive the micro-vibration displacement platform to vibrate continuously along the vector direction.

9. The dual grating angle adjustment rotary stage according to claim 1, characterized in that: The two sides of the smooth receiving screen are provided with completely identical grid-shaped engraved lines, a black circle center mark is provided at the center position of the diagonal line, and a telescopic rod is provided at the bottom of the smooth receiving screen.

10. A method for adjusting the parallelism of a grating pair, used for the double grating angle adjustment rotation stage as claimed in any one of claims 1 to 9, characterized in that Including grating surface parallel adjustment and grating line parallel adjustment, the specific steps are: Step 1: Use a telescopic grating fixture to clamp the calibration grating A and the grating to be measured B respectively, turn on the two line light sources, and the light is incident on the double grating through the horizontal collimated linear light formed by the horizontal slits. Control the handle of the rotating disk of the grating adjustment fixture holding the calibration grating A to drive the standard grating A to rotate until the reflected light of the standard grating A is observed on the light receiving screen. Adjust the X-axis pitch and Z-axis yaw ball head knobs of the grating three-axis adjustment device to make the reflected light parallel to the vertical scale of the grid-like scale on the light receiving screen, and record the angle scale value of the standard grating A displayed on the rotary angle control base at this time. According to the value, rotate the grating adjustment fixture holding the grating to be measured B to the corresponding angle value after increasing by 180°, observe the reflected light of the grating to be measured on the light receiving screen, adjust the X-axis pitch and Z-axis yaw ball head knobs of its grating three-axis adjustment device to make its reflected light also parallel to the vertical scale of the grid-like scale on the other side of the light receiving screen, and complete the parallel adjustment of the two grating surfaces; Step 2: Rotate the grating adjustment fixture that clamps the calibration grating A until the standard grating +1 order diffraction light and the standard grating +2 order diffraction light are observed on the light receiving screen, connect the points of the multi-order diffraction light on the light receiving screen into a diffraction light straight line, adjust the Y-axis rolling ball head knob of the corresponding grating adjustment fixture until the diffraction light straight line is parallel to the horizontal scale line of the grid-like scale line on the light receiving screen, then rotate the grating adjustment fixture that clamps the grating to be measured B until the standard grating +1 order diffraction light and the standard grating +2 order diffraction light are observed on the light receiving screen, connect the points of the multi-order diffraction light on the light receiving screen into a diffraction light straight line, adjust the Y-axis rolling ball head knob of the corresponding grating adjustment fixture so that the corresponding diffraction light straight line is also parallel to the horizontal scale line of the grid-like scale line on the light receiving screen, and complete the parallel adjustment of the two grating lines.

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