Calibration device based on polarization focusing optical system

Abstract

The invention discloses a calibration device based on a polarization focusing optical system. The calibration device comprises a beam splitter prism assembly. The photoelectric autocollimator and the high-precision adjusting rotary table are arranged on one side of the light inlet end of the beam splitter prism assembly; detected moving parts are arranged at the light emitting ends of the two sides of the beam splitter prism assembly; one end, matched with the light emitting end of the beam splitter prism assembly, of the detected moving part is provided with a coaxial lens barrel assembly; according to the calibration device, the straightness, the parallelism and the coaxiality of measured moving parts on the two sides are measured through a beam splitter prism assembly and a photoelectric autocollimator; when the straightness and the parallelism of the measured moving part are measured, the light emitting end of the beam splitter prism assembly is not provided with the switching objective lens; when the coaxiality of the measured moving part is measured, the switching objective lens is installed at the light emitting end of the beam splitter prism assembly. According to the calibration device, the shafting can be synchronously adjusted on line.

Description

Technical Field

[0001] The invention relates to the technical field of precision instruments, and in particular to a calibration device based on a polarization focusing optical system. Background Art

[0002] Due to different application scenarios and methods, existing methods are unable to measure the coaxiality, motion straightness and parallelism of two parallel rotating shafts under different working conditions. For example, the ruler and plug gauge method is generally used for machines with low speed and low precision requirements. The double-meter method is generally suitable for small and medium-sized machines that use rolling bearings and have small axial movement. The three-meter method is very accurate and suitable for precision machines and high-speed machines that require precise alignment, but the operation and calculation are relatively complicated. The laser alignment instrument is simple to operate, has a fast alignment speed and small error, but it is expensive and has high requirements on the user's quality.

[0003] Therefore, based on the above technical problems, technicians in this field urgently need to develop a calibration device based on a polarization focusing optical system. Summary of the invention

[0004] The purpose of the present invention is to provide a calibration device based on a polarization focusing optical system. The calibration device is based on the principle of a reflective centering instrument, takes a rotating axis system as a measurement reference, and uses a method in which an autocollimator and a front mirror cooperate to center the lens.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A calibration device based on a polarization focusing optical system of the present invention comprises:

[0007] A beam splitter prism assembly, wherein the beam splitter prism assembly has a light input end located at the front side thereof and light output ends located at both sides thereof;

[0008] A photoelectric autocollimator arranged at one side of the light incident end of the beam splitter prism assembly; and

[0009] High-precision adjustment turntable;

[0010] The light-emitting ends on both sides of the beam splitter prism assembly are both provided with a moving part to be measured;

[0011] The moving part to be measured cooperates with the light emitting end of the beam splitter prism assembly at one end with a coaxial lens barrel assembly;

[0012] The calibration device measures the straightness and parallelism of the moving parts to be measured on both sides through the beam splitter prism assembly and the photoelectric autocollimator, and can measure the coaxiality of the moving parts to be measured on both sides;

[0013] When measuring the straightness and parallelism of the moving part being measured, the light-emitting end of the beam splitter prism assembly is not equipped with a switching objective lens;

[0014] When measuring the coaxiality of the moving part being measured, a switching objective lens is installed at the light output end of the beam splitter prism assembly.

[0015] Furthermore, the high-precision adjustment turntable includes:

[0016] System base;

[0017] a turntable connector integrated into the system base; and

[0018] A high-precision Z-axis turntable and a high-precision Y-axis turntable assembled on the turntable connecting member;

[0019] The beam splitter prism assembly is connected to both the high-precision Z-axis turntable and the high-precision Y-axis turntable.

[0020] Furthermore, the coaxial lens barrel assembly comprises:

[0021] a centering lens barrel located at one end of the measured moving component close to the light emitting end; and

[0022] A double convex lens or a plane reflecting mirror is fixed in the centering lens barrel through a lens pressing ring.

[0023] Furthermore, the beam splitter prism assembly comprises:

[0024] A prism fixing seat, wherein the prism fixing seat is fixed to the high-precision Z-axis turntable by screws;

[0025] A polarization beam splitter cubic prism mounted on the prism fixing seat, wherein the upper end of the polarization beam splitter cubic prism is pressed by a prism gland;

[0026] An adjustment lens barrel integrated at the lower part of the prism fixing seat; and

[0027] A lens barrel installed in the adjusting lens barrel;

[0028] A quartz air gap zero-order wave plate and a plane reflector are fixed in the lens barrel through a reflector pressing ring, and the lens barrel is fixed to the adjustment lens barrel through a guide column on the side.

[0029] Furthermore, the switching objective lens installed at the light output end includes:

[0030] an objective lens barrel integrated in the light-emitting end; and

[0031] The objective lens is fixed in the objective lens barrel through an objective lens pressing ring.

[0032] Furthermore, the calibration method for measuring the straightness, parallelism and coaxiality of the moving parts to be measured on both sides by the calibration device mainly includes the following steps:

[0033] S1. Posture adjustment: replace the biconvex lens in the coaxial prism assembly of the moving part to be measured with a plane reflector of the same diameter, and do not install a switching objective lens at the light-emitting end. Adjust the photoelectric autocollimator and the beam splitter prism assembly so that the returned cross images received by the photoelectric autocollimator coincide with each other, indicating that the two light-emitting ends of the beam splitter prism assembly coincide with the ideal axis.

[0034] S2, measurement and calibration of straightness and parallelism, shield the light-emitting end of one side of the photoelectric autocollimator, move the moving part to be measured on the other side, during the movement, the cross image received by the photoelectric autocollimator will move, adjust the movement trajectory of the moving part to be measured, until the movement of the cross image during the movement is the smallest, complete the calibration of the straightness of the moving part to be measured on this side; then open the light-emitting end blocked by the side, move the moving part to be measured on this side, until the movement of the cross image during the movement is the smallest, complete the calibration of the movement parallelism of both sides, and the movement trajectory error is read out by the photoelectric autocollimator;

[0035] S3. Measurement and calibration of coaxiality. Install the coaxial lens barrel assembly and the switching objective lens. Use the objective lens with the same focal length when switching the objective lens. Move the moving part to be measured until the image of the center of the sphere is found. By rotating the moving part to be measured, you can see the image of the center of the sphere drawing a circle on the photoelectric autocollimator. This circle is the rotational eccentric trajectory of the moving part to be measured. Adjust the moving part to draw a circle to the minimum. Then replace it with another set of focused switching objective lenses. You can see another image of the center of the sphere of the double convex lens. Rotate the moving part to adjust the circle to the minimum. Repeatedly switch between the two sets of switching objective lenses. Iteratively adjust the two center of the sphere images to draw the minimum circle. At this time, it means that the axis connected by the two center of the spheres coincides with the ideal axis. After the adjustment on both sides is completed, it means that the rotation axes of the moving parts to be measured on both sides coincide.

[0036] In the above technical solution, the present invention provides a calibration device based on a polarization focusing optical system, which has the following beneficial effects:

[0037] The calibration device of the present invention is based on the principle of a reflective centering instrument, takes the rotating axis system as the measurement reference, and uses the method of cooperating the autocollimator with the front mirror to center the lens. The calibration device uses a polarization beam splitting cubic prism and a quartz air gap zero-order wave plate to obtain two parallel and oppositely directed light beams, and measures the spherical center of the same biconvex lens installed on different rotating axes through objective lenses with different focal lengths. The line connecting the spherical centers of the biconvex lenses represents the center of the rotating axis, and then measures the coordinates of the two spherical center endpoints of the rotating axis in space.

[0038] The calibration device of the present invention can not only adjust the axis system online synchronously, but also calculate the spatial axis system deviation through coordinates after the adjustment to compensate for the movement result. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0040] Figure 1 A schematic diagram of a calibration device based on a polarization focusing optical system provided by an embodiment of the present invention;

[0041] Figure 2 A schematic structural diagram of a calibration device based on a polarization focusing optical system provided by an embodiment of the present invention;

[0042] Figure 3 A schematic structural diagram of a coaxial lens barrel assembly of a calibration device based on a polarization focusing optical system provided by an embodiment of the present invention;

[0043] Figure 4 A schematic structural diagram of a beam splitter prism assembly and a switchable objective lens of a calibration device based on a polarization focusing optical system provided by an embodiment of the present invention.

[0044] Description of reference numerals:

[0045] 1. Photoelectric autocollimator; 2. Measured moving parts; 3. Beam splitter prism assembly; 4. High-precision Z-axis turntable; 5. High-precision Y-axis turntable; 6. Turntable connector; 7. System base; 8. Switching objective lens; 9. Coaxial lens barrel assembly;

[0046] 301, prism cover; 302, polarization beam splitter cubic prism; 303, adjustment lens barrel; 304, lens barrel; 305, quartz air gap zero-order wave plate; 306, plane reflector; 307, reflector pressure ring; 308, guide column; 309, prism fixing seat;

[0047] 801, objective lens barrel; 802, objective lens; 803, objective lens pressing ring;

[0048] 901, centering lens barrel; 902, double convex lens; 903, lens pressure ring. DETAILED DESCRIPTION

[0049] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0050] See also Figures 1 to 4 As shown;

[0051] A calibration device based on a polarization focusing optical system according to this embodiment includes:

[0052] A beam splitter prism assembly 3, wherein the beam splitter prism assembly 3 has a light input end located at the front side thereof and light output ends located at both sides thereof;

[0053] A photoelectric autocollimator 1 arranged at one side of the light incident end of the beam splitter prism assembly 3; and

[0054] High-precision adjustment turntable;

[0055] The light-emitting ends on both sides of the beam splitter prism assembly 3 are both provided with the moving parts 2 to be measured;

[0056] The moving part 2 to be measured and the light-emitting end of the beam splitter prism assembly 3 are matched with a coaxial lens barrel assembly 9;

[0057] The calibration device measures the straightness and parallelism of the moving parts 2 to be measured on both sides through the beam splitter prism assembly 3 and the photoelectric autocollimator 1, and can measure the coaxiality of the moving parts 2 to be measured on both sides;

[0058] When measuring the straightness and parallelism of the moving part 2 to be measured, the light-emitting end of the beam splitter prism assembly 3 is not equipped with a switching objective lens 8;

[0059] When measuring the coaxiality of the moving component 2 to be measured, a switching objective lens 8 is installed at the light output end of the beam splitter prism assembly 3 .

[0060] Among them, the high-precision adjustment turntable of this embodiment includes:

[0061] System base 7;

[0062] A turntable connector 6 integrated into the system base 7; and

[0063] A high-precision Z-axis turntable 4 and a high-precision Y-axis turntable 5 assembled on a turntable connecting member 6;

[0064] The beam splitter prism assembly 3 is connected to both the high-precision Z-axis turntable 4 and the high-precision Y-axis turntable 5 .

[0065] Preferably, the coaxial lens barrel assembly 9 of this embodiment includes:

[0066] A centering lens barrel 901 located at one end of the moving component 2 to be measured close to the light emitting end; and

[0067] The biconvex lens 902 or the plane reflector 306 is fixed in the centering lens barrel 901 by the lens pressing ring 903 .

[0068] The calibration device of this embodiment first discloses the structure of the coaxial lens barrel assembly 9 at the end of the moving component 2 to be measured close to the light-emitting end, which fixes the biconvex lens 902 in the centering lens barrel 901 through the lens pressure ring 903, and after the stopper of the centering lens barrel 901 is processed by a centering lathe, it is positioned and placed in the moving component 2 to be measured through the stopper.

[0069] Secondly, the beam splitter prism assembly 3 of this embodiment includes:

[0070] A prism fixing seat 309, which is fixed to the high-precision Z-axis turntable 4 by screws;

[0071] A polarization beam splitter cube prism 302 mounted on a prism holder 309, wherein the upper end of the polarization beam splitter cube prism 302 is pressed by a prism cover 301;

[0072] An adjustment lens barrel 303 integrated at the bottom of the prism holder 309; and

[0073] A lens barrel 304 installed in the adjustment lens barrel 303;

[0074] A quartz air gap zero-order wave plate 305 and a plane reflector 306 are fixed in the lens barrel 304 via a reflector pressing ring 307 , and the lens barrel 304 is fixed to the adjustment lens barrel 303 via a guide column 308 on the side.

[0075] This embodiment further defines the structural composition of the beam splitter prism assembly 3. First, the prism holder 309 is fixed on the high-precision Z-axis turntable 4 by screws, and the polarization beam splitter cube prism 302 is fixed in the prism holder 309 by the prism cover 301. Secondly, the quartz air gap zero-order wave plate 305 and the plane reflector 306 are fixed in the lens barrel 304 by the reflector pressing ring 307, and finally installed in the adjustment lens barrel 303, and then fixed by the guide column 308.

[0076] Preferably, the switching objective lens 8 installed at the light output end of this embodiment includes:

[0077] An objective lens barrel 801 integrated at the light output end; and

[0078] The objective lens 802 is fixed in the objective lens barrel 801 by the objective lens pressing ring 803 .

[0079] The photoelectric autocollimator 1 of the calibration device of this embodiment emits parallel light to the polarization beam splitter cube prism 302, one beam is reflected to the right, and the other beam passes through the reflection surface, passes through the quartz air gap zero-order wave plate 305, and then is reflected by the plane reflector 306 and passes through the quartz air gap zero-order wave plate 305 again, and is reflected to the left at the splitting point of the polarization beam splitter cube prism 305. The light emitted from the left and right sides is still a parallel beam. By cooperating with the principle of the reflector, the measurement and calibration of the motion straightness and parallelism can be carried out. By using the centering principle and adding a switching objective lens 8 with different focal lengths, the measurement and calibration of the coaxiality can be measured.

[0080] The calibration method for measuring the straightness, parallelism and coaxiality of the moving parts 2 to be measured on both sides based on the calibration device of the present application mainly includes the following steps:

[0081] S1, posture adjustment, replace the biconvex lens 902 in the coaxial prism assembly 9 of the moving part to be measured with a plane reflector 306 with the same diameter, and do not install the switching objective lens 8 at the light-emitting end, adjust the photoelectric autocollimator 1 and the beam splitter prism assembly 3 so that the returned cross image received by the photoelectric autocollimator 1 coincides, indicating that the two light-emitting ends of the beam splitter prism assembly 3 coincide with the ideal axis;

[0082] S2, measurement and calibration of straightness and parallelism, shielding the light-emitting end on one side of the photoelectric autocollimator 1, moving the moving component 2 to be measured on the other side, during the movement, the cross image received by the photoelectric autocollimator 1 will move, adjusting the movement trajectory of the moving component 2 to be measured, until the movement amount of the cross image during the movement is the smallest, completing the calibration of the straightness of the moving component 2 to be measured on this side; then opening the light-emitting end blocked by the side, moving the moving component 2 to be measured on this side, until the movement amount of the cross image during the movement is the smallest, completing the calibration of the parallelism of the movement on both sides, and the movement trajectory error is read out by the photoelectric autocollimator 1;

[0083] S3, measurement and calibration of coaxiality, install the coaxial lens barrel assembly 9 and the switching objective lens 8, the switching objective lens 8 uses the objective lens 802 of the same focal length, move the measured moving component 2 until the spherical center image is found, rotate the measured moving component 2 to see the spherical center image drawing a circle on the photoelectric autocollimator 1, this circle is the rotation eccentric trajectory of the measured moving component 2, adjust the measured moving component 2 until the circle drawing amount is minimized; then replace with another set of focused switching objective lenses 8, you can see another spherical center image of the biconvex lens 902, rotate the measured moving component 2 to adjust the circle drawing amount to the minimum; repeatedly switch between the two sets of switching objective lenses 8, iteratively adjust the two spherical center images to the minimum circle drawing amount, this time it means that the axis connected by the two spherical centers coincides with the ideal axis, after the adjustment on both sides is completed, it means that the rotation axis of the measured moving component 2 on both sides coincides.

[0084] As an extended implementation:

[0085] The calibration device is used to measure and calibrate the dual-axis straightness, parallelism and coaxiality: the single-axis measurement is the same as the above method, and the high-precision Z-axis turntable 4 is rotated 90 degrees and the above single-axis operation steps are repeated to adjust and measure the structure to obtain data.

[0086] The calibration device is used to measure and calibrate the three-axis straightness, parallelism and coaxiality: on the basis of the two-axis measurement and calibration steps, the high-precision Y-axis turntable 5 is rotated 90 degrees and the above single-axis operation steps are repeated to adjust and measure the results to obtain data.

[0087] In the above technical solution, the present invention provides a calibration device based on a polarization focusing optical system, which has the following beneficial effects:

[0088] The calibration device of the present invention is based on the principle of a reflective centering instrument, takes the rotating axis system as the measurement reference, and uses the method of cooperating the autocollimator 1 with the front mirror to center the lens. The calibration device uses a polarization beam splitting cubic prism 302 and a quartz air gap zero-order wave plate 305 to obtain two parallel and oppositely directed light beams, and measures the spherical center of the same biconvex lens 902 installed on different rotating axes through an objective lens 802 with different focal lengths, and uses the connecting line of the spherical center of the biconvex lens 902 to represent the center of the rotating axis, thereby measuring the coordinates of the two spherical center endpoints of the rotating axis in space.

[0089] The calibration device of the present invention can not only adjust the axis system online synchronously, but also calculate the spatial axis system deviation through coordinates after the adjustment to compensate for the movement result.

[0090] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A calibration device based on a polarization focusing optical system, characterized in that: The calibration device includes: A beam splitter prism assembly (3), wherein the beam splitter prism assembly (3) has a light input end located at the front side thereof and light output ends located at both sides thereof; a photoelectric autocollimator (1) arranged on one side of the light incident end of the beam splitting prism assembly (3); and High-precision adjustment turntable; The light-emitting ends on both sides of the beam splitter prism assembly (3) are both provided with a moving part (2) to be measured; The moving part to be measured (2) and the light emitting end of the beam splitter prism assembly (3) are matched with each other at one end and have a coaxial lens barrel assembly (9); The calibration device measures the straightness and parallelism of the moving parts (2) to be measured on both sides through the beam splitter prism assembly (3) and the photoelectric autocollimator (1), and can also measure the coaxiality of the moving parts (2) to be measured on both sides; When measuring the straightness and parallelism of the moving part (2) being measured, the light output end of the beam splitter prism assembly (1) is not equipped with a switching objective lens (8); When measuring the coaxiality of the measured moving component (2), a switching objective lens (8) is installed at the light output end of the beam splitter prism assembly (1).

2. The calibration device based on the polarization focusing optical system according to claim 1, characterized in that: The high-precision adjustment turntable comprises: System base (7); A turntable connector (6) integrated into the system base (7); and A high-precision Z-axis turntable (4) and a high-precision Y-axis turntable (5) assembled on the turntable connecting member (6); The beam splitter prism assembly (1) is connected to both the high-precision Z-axis turntable (4) and the high-precision Y-axis turntable (5).

3. The calibration device based on the polarization focusing optical system according to claim 2, characterized in that: The coaxial lens barrel assembly (9) comprises: a centering lens barrel (901) located at one end of the measured moving component (2) close to the light emitting end; and A double convex lens (902) or a plane reflecting mirror (306) is fixed in the centering lens barrel (901) via a lens pressing ring (903).

4. The calibration device based on the polarization focusing optical system according to claim 3, characterized in that: The beam splitter prism assembly (3) comprises: A prism fixing seat (309), wherein the prism fixing seat (309) is fixed to the high-precision Z-axis turntable (4) by means of screws; A polarization beam splitting cubic prism (302) mounted on the prism fixing seat (309), wherein the upper end of the polarization beam splitting cubic prism (302) is pressed by a prism pressing cover (301); an adjustment lens barrel (303) integrated at the lower part of the prism fixing seat (309); and A lens barrel (304) installed in the adjusting lens barrel (303); A quartz air gap zero-order wave plate (305) and a plane reflector (306) are fixed in the lens barrel (304) via a reflector pressing ring (307), and the lens barrel (304) is fixed to the adjustment lens barrel (303) via a guide column (308) on the side.

5. The calibration device based on the polarization focusing optical system according to claim 4, characterized in that: The switching objective lens (8) installed at the light output end comprises: an objective lens barrel (801) integrated at the light output end; and An objective lens (802) is fixed in the objective lens barrel (801) via an objective lens pressing ring (803).

6. The calibration device based on the polarization focusing optical system according to claim 5, characterized in that: The calibration method for measuring the straightness, parallelism and coaxiality of the moving parts (2) to be measured on both sides by the calibration device mainly comprises the following steps: S1, posture adjustment, replacing the biconvex lens (902) in the coaxial prism assembly (9) of the measured moving part (2) with a plane reflector (306) of the same diameter, and not installing the switching objective lens (8) at the light output end, adjusting the photoelectric autocollimator (1) and the beam splitter prism assembly (3) so that the returned cross image received by the photoelectric autocollimator (1) coincides, indicating that the two light output ends of the beam splitter prism assembly (3) coincide with the ideal axis; S2, measurement and calibration of straightness and parallelism, shielding the light emitting end of one side of the photoelectric autocollimator (1), moving the moving component (2) to be measured on the other side, during the movement, the cross image received by the photoelectric autocollimator (1) will move, adjusting the movement trajectory of the moving component (2) to be measured until the movement amount of the cross image during the movement is minimized, completing the calibration of the straightness of the moving component (2) to be measured on this side; then opening the light emitting end blocked by the side, moving the moving component (2) to be measured on this side, until the movement amount of the cross image during the movement is minimized, completing the calibration of the movement parallelism of both sides, and the movement trajectory error is read out by the photoelectric autocollimator; S3, coaxiality measurement and calibration, install the coaxial lens barrel assembly (9) and the switching objective lens (8), use the objective lens (802) of the same focal length for the switching objective lens (8), move the measured moving part (2) until the spherical center image is found, rotate the measured moving part (2) to see the spherical center image drawing a circle on the photoelectric autocollimator (1), this circle is the rotation eccentric trajectory of the measured moving part (2), adjust the measured moving part (2) until the circle drawing amount is minimized; then replace with another set of focused switching objective lenses (8), another spherical center image of the double convex lens (902) can be seen, rotate the measured moving part (2) to adjust the circle drawing amount to be minimized; repeatedly switch the two sets of switching objective lenses (8), iteratively adjust the two spherical center images to the minimum circle drawing amount, at this time it means that the axis connected by the two spherical centers coincides with the ideal axis, after the adjustment on both sides is completed, it means that the rotation axis of the measured moving part (2) on both sides coincides, the photoelectric autocollimator (1) records the spatial positions of the four spherical centers, and the different axis degrees can be calculated by formula.

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