Adjustable autocollimator optical path system and optical path debugging method

Abstract

The present application relates to a tunable autocollimator optical path system and optical path debugging method, the system comprises an autocollimator, a light splitting prism, an aperture diaphragm, a mirror, a plane mirror, a CCD module, an imaging surface module, a camera, the plane mirror is located on the reflected light path of the mirror, the CCD module is arranged on the reflected light path of the light splitting prism, the imaging surface module is located on the back of the plane mirror, the camera shoots the light spot appearance and judges the inclination angle of the outgoing light source. In one aspect of the present application, the overall structure of the autocollimator is coaxial with the incident light path and the reflected light path, which meets the debugging requirements and modular design of the functional modules, realizes dynamic flatness measurement, simplifies the adjustment process, reduces the debugging time, improves the debugging efficiency, and improves the measurement accuracy of the autocollimator by monitoring the position and appearance of the reflected light spot and the outgoing light spot through the computer; on the other hand, the modules in the autocollimator are not only convenient to install and debug, but also the same modules can be replaced with each other, which is convenient for the maintenance of the autocollimator.

Description

Technical Field

[0001] This invention belongs to the field of optical technology, specifically relating to an adjustable autocollimator optical path system, and also to an adjustable autocollimator optical path adjustment method. Background Technology

[0002] With the rapid development of science and technology and production processes, it is crucial to achieve rapid, high-precision, non-contact, easy-to-operate, and stable and reliable detection of minute angle measurements, such as workpiece tilt measurement, flatness measurement of flat plates, angular wobble measurement of shaft systems, and straightness measurement of guide rails. Examples include: angle measurement of prism surfaces, flatness measurement of plane mirror surfaces, measurement of the movement of machine tool slides on the machine bed, and measurement of the perpendicular angle between the machine tool spindle and the worktable. These workpieces and equipment are often processed or used on automated production lines, and the improvement of their processing level is often closely linked to the continuous improvement of measurement technology. Product quality is largely determined by the accuracy of monitoring instruments.

[0003] However, traditional optical measurement methods suffer from low accuracy and long measurement times due to issues such as instrument precision and human eye errors, and they cannot achieve dynamic measurements. Therefore, developing precision testing instruments for measuring minute angles with high precision, fast detection speed, reliable and stable performance, and ease of operation is of great significance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an improved adjustable autocollimator optical path system.

[0005] Meanwhile, the present invention also relates to an optical path debugging method for an adjustable autocollimator.

[0006] To solve the above technical problems, the present invention adopts the following technical solution:

[0007] An adjustable autocollimator optical path system includes an autocollimator, a reflector, and a plane reflector, wherein the plane reflector is located on the reflected optical path of the reflector. In particular, the adjustable autocollimator optical path system also includes a beam splitter prism and an aperture stop located between the autocollimator and the reflector, a CCD module disposed on the reflected optical path of the beam splitter prism, an imaging surface module located on the back of the plane reflector, and a camera that receives the light spot morphology. The tilt angle of the emitted light source is determined based on the light spot morphology acquired by the camera, and the tilt angle of the reflector is 4 to 45°.

[0008] Preferably, a collimating lens module is also provided between the beam splitter prism and the aperture stop.

[0009] According to a specific embodiment and preferred aspect of the present invention, the center lines of the light-emitting surfaces of the collimating lens module, the beam splitter prism, and the autocollimator are on the same straight line.

[0010] Specifically, the aperture stop diameter is set to 10±2mm; and / or, the collimating lens module uses a plano-convex lens with a focal length of 60±2mm and an aperture of 40±2mm for collimation of the fiber laser and imaging of the aperture stop; and / or, the light source is located at the focal point of the lens, and the emitted light is a parallel beam. The center lines of the collimating lens module, the beam splitter, and the light-emitting surface of the light source are on the same straight line, and the CCD module and the center of the beam splitter are on the same straight line and located on the reflected light path; and / or, the tilt angle of the reflector is 4~45° (more preferably 6~40°), and the parallel beam of light passing through the collimating lens returns along the original path after passing through the reflecting mirror and the plane reflector; the radius of curvature of the plane reflector is infinite, and the aperture is 2±0.1mm.

[0011] Another technical solution of the present invention is: an optical path debugging method for an adjustable self-collimator optical path system, characterized in that it includes the following steps:

[0012] 1) Level the autocollimator optical path system and place it on the optical platform. Place the functional modular autocollimator vertically on the optical platform and build the optical path system in sequence according to the outgoing light path. The optical path system includes the autocollimator, beam splitter, collimating lens module, aperture stop, mirror, plane mirror, CCD module, imaging surface module and camera.

[0013] 2) Turn on the laser source, adjust the collimating lens module to make the outgoing light parallel, and keep the outgoing light passing through the center of the aperture stop;

[0014] 3) Aperture stop imaging adjustment: The aperture stop is adjusted axially, and the image of the emitted beam in the autocollimator passing through the aperture stop is observed through the CCD module. After the aperture stop image is clear, the aperture stop is fixed on the autocollimator housing.

[0015] 4) Adjust the output optical path and optical axis, adjust the tilt angle of the light source, observe the light spot on the imaging surface module through the camera, return the tilt angle of the light source to zero, and fix the light source on the base of the autocollimator with fixing screws;

[0016] 5) Adjust the optical axis of the reflected light path, adjust the tilt angle of the reflector appropriately, observe the position of the reflected light spot on the image plane of the aperture through the CCD module, and fix the reflector when the reflected light spot is located at the center of the aperture.

[0017] Preferably, the light source is a fiber laser, the beam splitter is set in the output light path of the light source module, and the CCD module is set in the reflected light path of the beam splitter; the collimating lens module is set in the output light path of the beam splitter, and the collimating lens module is tightly fitted to the bottom of the device housing. An aperture stop for light transmission is also set between the beam splitter and the collimating lens module.

[0018] According to a specific embodiment and preferred aspect of the present invention, the aperture stop diameter is set to 10±2mm; and / or, the collimating lens module is selected from a plano-convex lens with a focal length of 60±2mm and an aperture of 40±2mm for collimation of the fiber laser and imaging of the aperture stop; and / or, the light source is located at the focal point of the lens, and the emitted light is a parallel beam.

[0019] Preferably, the collimating lens module, the beam splitter, and the center line of the light-emitting surface of the light source are on the same straight line; the center of the CCD module and the beam splitter are on the same straight line and located on the reflected light path; and / or, the tilt angle of the reflector is 4-45°, and the parallel light beam passing through the collimating lens returns along the original path after passing through the reflecting mirror and the plane reflector; the radius of curvature of the plane reflector is infinite, and the aperture is 2±0.1mm.

[0020] In some specific implementations, the positions of the aperture stop and the CCD conform to the Gaussian formula of geometrical optics:

[0021]

[0022] Where L' and L are the image distance and object distance, respectively, which are the distances from the CCD detector to the principal plane of the collimating lens and the distances from the aperture to the principal plane of the collimating lens; f' is the focal length of the collimating lens.

[0023] Furthermore, in step 4), the light spot pattern on the imaging surface is observed through the camera. Once the light spot intensity distribution is the same, that is, the angle θ between the outgoing light path and the vertical direction is 0, the light source is fixed on the base of the autocollimator with fixing screws. In short, the outgoing light path of the light source is perpendicular and concentric with the autocollimator and the collimating lens module. The tilt angle of the light source is adjusted appropriately, the angle θ between the outgoing light path and the vertical direction, the angle α between the reflected light path and the horizontal axis, and the tilt angle of the reflector are 4-45°. The light spot pattern on the imaging surface is observed through the camera. Once the light spot intensity distribution is the same, that is, the angle θ between the outgoing light path and the vertical direction is 0, the light source is fixed on the base of the autocollimator with fixing screws.

[0024] In step 5), the tilt angle α of the plane mirror is adjusted. The distance L between the reflected light spot and the center of the aperture stop is observed through the CCD module, and the distance d between the CCD module and the mirror is measured. The angle β between the reflected light path and the horizontal direction is twice the tilt angle α of the plane mirror, and its angle can be calculated using the following formula: By adjusting the tilt angle of the plane mirror, the reflected light spot is positioned at the exact center of the aperture, and the mirror is then fixed in place with fixing screws.

[0025] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art:

[0026] Existing optical measurements suffer from low accuracy, long measurement times, and inability to perform dynamic measurements due to issues such as instrument precision and human eye errors. This invention cleverly solves these shortcomings through an overall design of an adjustable autocollimator optical path system. After adopting this adjustable autocollimator optical path system, the laser light incident from the incident light path passes sequentially through the beam splitter prism, aperture stop, and reflector, and then returns along the original path after passing through the reflector and plane reflector. Since the aperture of the reflector is smaller than the size of the beam, the remaining beam can continue to be received by the imaging surface through the edge of the reflector and can also be received by the camera. Then, the tilt degree of the outgoing light source can be determined by the shape of the light spot received by the camera. Therefore, on the one hand, the overall structure of the autocollimator of this invention is designed with the incident light path and the reflected light path coaxial to meet the debugging requirements and functional modular design, realizing dynamic flatness measurement, simplifying the adjustment process, reducing debugging time, and improving debugging efficiency. At the same time, the position and shape of the reflected light spot and the outgoing light spot are monitored by computer, improving the measurement accuracy of the autocollimator. On the other hand, the modules in the autocollimator are not only easy to install and debug, but the same modules can also be interchanged, which facilitates the maintenance of the autocollimator. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the optical path principle of the autocollimator optical path system in this embodiment;

[0028] Figure 2 This is a schematic diagram of the optical path principle for adjusting the optical axis of the outgoing optical path in this embodiment;

[0029] Figure 3 This is a schematic diagram of the optical path principle for adjusting the optical axis of the reflected optical path in this embodiment;

[0030] The components include: 1. Autocollimator; 2. Beam splitter prism; 3. CCD module; 4. Collimating lens module; 5. Aperture stop; 6. Mirror; 7. Plane mirror; 8. Imaging surface module; and 9. Camera. Detailed Implementation

[0031] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] In this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0036] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0037] like Figure 1 As shown, the adjustable autocollimator optical path system of this embodiment includes an autocollimator 1, a beam splitter 2, a CCD module 3, a collimating lens module 4, an aperture stop 5, a reflector 6, a plane reflector 7, an imaging surface module 8, and a camera 9. The autocollimator 1, beam splitter 2, collimating lens module 4, aperture stop 5, and reflector 6 are arranged sequentially from top to bottom. The CCD module 3 is arranged on the reflected light path of the beam splitter prism. The plane reflector 7 is located on the reflected light path of the reflector 6. The imaging surface module 8 is located on the back (left side) of the plane reflector 7. The camera 9 receives the light spot shape and determines the tilt angle of the emitted light source based on the light spot shape received by the camera 9.

[0038] In some specific embodiments, the light source is located at the focal point of the lens, and the emitted light is a parallel beam. The collimating lens module 4, the beam splitter 2, and the center line of the light-emitting surface of the light source are on the same straight line. The CCD module 3 and the center of the beam splitter 2 are on the same straight line and located on the reflected light path. The tilt angle of the reflector is 4 to 45° (generally 6 to 40°). After the parallel beam of light passes through the collimating lens, it returns along the original path after passing through the reflector and the plane reflector. The radius of curvature of the plane reflector is infinite, and the aperture is 2 ± 0.1 mm. The aperture stop 5 is set to a diameter of 10 ± 2 mm. The collimating lens module 4 uses a plano-convex lens with a focal length of 60 ± 2 mm and an aperture of 40 ± 2 mm for collimation of the fiber laser and imaging of the aperture stop.

[0039] Furthermore, this embodiment uses a large-area CCD with a target area of ​​2048*2048, and connects it to a computer for use, which greatly improves the image acquisition range and processing speed. At the same time, compared with the existing linear CCD, the area CCD can better measure and process dynamic images, further improving the measurement accuracy and efficiency of the product, making the product better able to meet the needs of users and greatly expanding the applicability of the product.

[0040] The optical path debugging method of this embodiment includes the following steps:

[0041] 1) Place the leveling autocollimator optical path system on the optical platform, vertically place the modular autocollimator on the optical platform, and assemble the optical path system sequentially according to the output optical path. Figure 1The optical path shown is described in the figure. The optical path system includes an autocollimator 1, a beam splitter 2, a collimating lens module 4, an aperture stop 5, a reflector 6, a plane reflector 7, a CCD module 3, an imaging surface module 8, and a camera 9.

[0042] 2) Turn on the laser source, adjust the collimating lens module to make the outgoing light parallel, and keep the outgoing light passing through the center of the aperture stop;

[0043] 3) Aperture stop imaging adjustment: The aperture stop is adjusted axially, and the image of the emitted beam in the autocollimator passing through the aperture stop is observed through the CCD module. After the aperture stop image is clear, the aperture stop is fixed on the autocollimator housing.

[0044] 4) Adjust the output optical path and optical axis, adjust the tilt angle of the light source, observe the light spot on the imaging surface module through the camera, return the tilt angle of the light source to zero, and fix the light source on the base of the autocollimator with fixing screws;

[0045] 5) Adjust the optical axis of the reflected light path, adjust the tilt angle of the reflector appropriately, observe the position of the reflected light spot on the image plane of the aperture through the CCD module, and fix the reflector when the reflected light spot is located at the center of the aperture.

[0046] In some specific implementations, the positions of the aperture stop and the CCD in step 3) conform to the Gaussian formula of geometrical optics:

[0047]

[0048] Where L' and L are the image distance and object distance, respectively, which are the distances from the CCD detector to the principal plane of the collimating lens and the distances from the aperture to the principal plane of the collimating lens; f' is the focal length of the collimating lens.

[0049] In step 4), combined Figure 2 As shown, observe the light spot pattern on the imaging surface through the camera. When the light spot intensity distribution is the same, that is, the angle θ between the outgoing light path and the vertical direction is 0, fix the light source on the base of the autocollimator with fixing screws. In short, the outgoing light path of the light source is perpendicular and concentric with the autocollimator and the collimating lens module. Adjust the tilt angle of the light source appropriately, the angle θ between the outgoing light path and the vertical direction, the angle α between the reflected light path and the horizontal axis, and the tilt angle of the reflector 6 between 4 and 45°. Observe the light spot pattern on the imaging surface through the camera. When the light spot intensity distribution is the same, that is, the angle θ between the outgoing light path and the vertical direction is 0, fix the light source on the base of the autocollimator with fixing screws.

[0050] In step 5), combined Figure 3As shown, by adjusting the tilt angle α of the plane mirror, the distance L between the reflected light spot and the center of the aperture stop is observed through the CCD module, and the distance d between the CCD module and the mirror is measured. The angle β between the reflected light path and the horizontal direction is twice the tilt angle α of the plane mirror, and this angle can be calculated using the following formula: By adjusting the tilt angle of the plane mirror, and considering the angle between the incident ray and the normal of the plane mirror, and the angle between the reflected light path and the perpendicular light path, the tilt of the plane mirror causes the reflected light path to deflect. Once the reflected light spot is located at the center of the aperture, the mirror is fixed with fixing screws.

[0051] In summary, by adopting this adjustable autocollimator optical path system, the laser light incident from the incident light path sequentially passes through the beam splitter, aperture stop, and reflector, and then returns along the original path after passing through the reflector and plane reflector. Since the aperture of the reflector is smaller than the beam size, the remaining beam can continue to be received by the imaging surface through the edge of the reflector and can also be received by the camera. Then, the tilt degree of the outgoing light source can be determined by the shape of the light spot received by the camera. Therefore, on the one hand, the overall structure of the autocollimator of this invention is designed to meet the debugging requirements of the incident light path and the reflected light path being coaxial and to be functionally modular, realizing dynamic flatness measurement, simplifying the adjustment process, reducing debugging time, and improving debugging efficiency. At the same time, the position and shape of the reflected light spot and the outgoing light spot are monitored by computer, improving the measurement accuracy of the autocollimator. On the other hand, the modules in the autocollimator are not only easy to install and debug, but the same modules can also be interchanged, facilitating the maintenance of the autocollimator. On the third hand, accurate monitoring results are obtained through aperture imaging debugging, outgoing light path optical axis debugging, and reflected light path optical axis debugging.

[0052] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A method for adjusting the optical path of an adjustable autocollimator optical path system, wherein the adjustable autocollimator optical path system comprises an autocollimator, a reflector, and a plane reflector, wherein the plane reflector is located on the reflected optical path of the reflector, characterized in that, The adjustable autocollimator optical path system also includes a beam splitter prism, a collimating lens module, and an aperture stop arranged sequentially between the autocollimator and the reflector; a CCD module disposed on the reflecting optical path of the beam splitter prism; an imaging surface module located on the back of the planar reflector; and a camera that receives the light spot morphology. The method involves determining the tilt angle of the outgoing light source based on the light spot morphology acquired by the camera, and includes the following steps: 1) The autocollimator optical path system is placed on the optical platform and leveled, and the optical path system is built. The optical path system includes an autocollimator, a beam splitter, a collimating lens module, an aperture stop, a mirror, a plane mirror, a CCD module, an imaging surface module, and a camera. 2) Turn on the laser source, adjust the collimating lens module to make the outgoing light parallel, and keep the outgoing light passing through the center of the aperture stop; 3) Aperture stop imaging adjustment: The aperture stop is adjusted axially, and the image of the emitted beam in the autocollimator passing through the aperture stop is observed through the CCD module. After the aperture stop image is clear, the aperture stop is fixed on the autocollimator housing. 4) Adjust the output optical path and optical axis, adjust the tilt angle of the light source, observe the light spot on the imaging surface module through the camera, return the tilt angle of the light source to zero, and fix the light source on the base of the autocollimator with fixing screws; 5) Adjust the optical axis of the reflected light path, adjust the tilt angle of the reflector appropriately, observe the position of the reflected light spot on the aperture stop image plane through the CCD module, and fix the reflector when the reflected light spot is located at the center of the aperture stop.

2. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1, characterized in that, The light source uses a fiber laser. A beam splitter is placed in the output light path of the light source module, and a CCD module is placed in the reflected light path of the beam splitter. A collimating lens module is placed in the output light path of the beam splitter. The collimating lens module is tightly fitted to the bottom of the device housing and is placed between the beam splitter and the aperture stop for light transmission.

3. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1 or 2, characterized in that, The aperture stop is set to a diameter of 10±2mm; and / or, the collimating lens module uses a plano-convex lens with a focal length of 60±2mm and an aperture of 40±2mm for collimation of the fiber laser and imaging of the aperture stop; and / or, the light source is located at the focal point of the lens, and the emitted light is a parallel beam.

4. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1 or 2, characterized in that, The collimating lens module, the beam splitter, and the center line of the light-emitting surface of the light source are on the same straight line; the center of the CCD module and the beam splitter are on the same straight line and located on the reflected light path; and / or, the tilt angle of the reflector is 4 to 45°, and the parallel light beam passing through the collimating lens returns along the original path after passing through the reflecting mirror and the plane reflector; the radius of curvature of the plane reflector is infinite, and the aperture is 2 ± 0.1 mm.

5. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1, characterized in that, The positions of the aperture stop and the CCD module conform to the Gaussian formula of geometrical optics: , where L' and L are the image distance and object distance, respectively, that is, the distance from the CCD module detector to the principal plane of the collimating lens and the distance from the aperture stop to the principal plane of the collimating lens; f' is the focal length of the collimating lens.

6. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1, characterized in that, In step 4), observe the light spot pattern on the imaging surface using the camera. Once the light spot intensity distribution is uniform, i.e., the angle θ between the outgoing light path and the vertical direction is 0, fix the light source on the base of the autocollimator using fixing screws; and / or, in step 5), adjust the tilt angle α of the plane mirror, observe the distance L between the reflected light spot and the center of the aperture stop through the CCD module, and measure the distance d between the CCD module and the mirror. The angle β between the reflected light path and the horizontal direction is twice the tilt angle α of the plane mirror, and can be calculated using the following formula: By adjusting the tilt angle of the plane mirror, the reflected light spot is positioned at the exact center of the aperture, and the mirror is then fixed in place with fixing screws.

7. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1, characterized in that, The center lines of the light-emitting surfaces of the collimating lens module, the beam splitter prism, and the autocollimator are all on the same straight line.

8. The optical path debugging method for the adjustable autocollimator optical path system according to claim 1, characterized in that, The CCD module and the center of the beam splitter are on the same straight line and located on the reflected light path.

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