A machining method of large-size high-precision optical parts

Abstract

The application relates to the technical field of optical part processing, and provides a processing method of large-size high-precision optical parts, which comprises the following steps: processing first, second, third and fourth side faces to first face shape parameters; placing a disc on a platform, placing a microcrystalline block between the platform and the disc, placing an optical part with the second end face downward into an avoiding hole, and then installing a positioning plate to the disc, wherein the positioning plate abuts against the first, second, third and fourth side faces; grinding and polishing the first end face to the first face shape parameters, so as to ensure that the first end face is perpendicular to the four side faces and the angle error is not greater than a first angle threshold; and grinding and polishing the second end face to the first face shape parameters according to the method of processing the first end face. The processing method can process large-size high-precision optical parts by using the traditional optical cold processing method through a reasonable technological process and a specially designed end face processing tool.

Description

Technical Field

[0001] This invention relates to the field of optical component processing technology, and more specifically, to a method for processing large-size, high-precision optical components. Background Technology

[0002] Optical component manufacturing refers to the process of precision machining various optical materials to meet specific optical performance requirements. These components are widely used in optical instruments, laser equipment, imaging systems, optical communications, and many other fields. Depending on the specific needs, optical component manufacturing can be divided into multiple steps, including but not limited to design, material selection, rough machining, finish machining, polishing, and coating.

[0003] For the processing of cubic optical components, all six sides need to be polished. Conventional processing methods can process the large side surfaces, but when the size of the optical components is large, conventional processing methods cannot meet the processing requirements of the two end surfaces. On the one hand, due to the influence of the large size, the two end surfaces of the component are not easy to be stably positioned, resulting in poor processing results. On the other hand, due to the insufficient stability of positioning, the safety and rationality of processing are reduced. As a result, conventional processing methods cannot meet the processing requirements of large-sized optical components, and specific processing tooling and inspection methods are required.

[0004] Therefore, existing technologies still need improvement and development. Summary of the Invention

[0005] The purpose of this invention is to propose a processing method for large-size, high-precision optical components, in order to solve the technical problem that conventional processing methods cannot meet the processing requirements of large-size optical components.

[0006] To achieve the above objectives, the present invention provides a method for processing large-size, high-precision optical components. The optical component is cubic, comprising a first side, a second side, a third side, a fourth side connected in sequence, and a first end face and a second end face disposed opposite to each other. A positioning fixture is also provided, comprising a disk, a positioning plate, and a microcrystalline block. The disk has a clearance hole at its center, the positioning plate is detachably connected to the top of the disk, and the microcrystalline block protrudes from the bottom of the disk.

[0007] The processing method includes:

[0008] Process the first side surface, the second side surface, the third side surface, and the fourth side surface to the first surface shape parameters;

[0009] Protect the four sides of the optical component with protective adhesive, place the disk on the platform, place the microcrystalline block between the platform and the disk, place the second end face of the optical component into the clearance hole, and then install the positioning plate onto the disk. The positioning plate abuts against the first side, the second side, the third side and the fourth side. Fill the gap between the optical component and the positioning plate with beeswax.

[0010] Grind and polish the first end face to the first surface shape parameters to ensure that the first end face is perpendicular to the four sides and that the angle error is not greater than the first angle threshold.

[0011] Place the first end face down into the clearance hole, and reinforce the four sides with the positioning plate;

[0012] Following the method for processing the first end face, the second end face is sanded and polished to the first surface shape parameter to ensure that the second end face is parallel to the first end face and the parallelism error is not greater than the first parallelism threshold.

[0013] Remove the optical components from the tray and clean them.

[0014] Furthermore, the grinding and polishing of the first end face to the first surface shape parameters specifically includes:

[0015] Hand-grind the positioning plate and the first end face as a whole, use coarse sandpaper to remove the first dimension, and then use fine sandpaper to remove the second dimension. While removing the first end face dimension, continuously adjust the tilt angle of the first end face to ensure that the first end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0016] The positioning plate and the first end face are polished as a whole. The third dimension is removed by high-speed polishing with a ring polishing machine. The angles of the four sides and the first end face are detected by a comparator. Based on the detection values, the first end face is polished at low speed to the first surface shape parameters, so that the first end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0017] Further, the step of low-speed polishing of the first end face to the first surface shape parameters based on the detected value specifically includes:

[0018] When the detection value shows an acute angle, increase the polishing pressure on one side of the acute angle to remove more dimensions on that side.

[0019] When the detected value shows an obtuse angle, increase the polishing pressure on the side opposite to the acute angle.

[0020] Furthermore, the method for processing the first end face, specifically including grinding and polishing the second end face to the first surface shape parameters, includes:

[0021] Hand-grind the positioning plate and the second end face as a whole. Use coarse sandpaper to remove the first dimension, and then use fine sandpaper to remove the second dimension. While removing the second end face dimension, adjust the tilt angle of the second end face to ensure that the second end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0022] The positioning plate and the second end face are polished as a whole. The third dimension is removed by high-speed polishing with a ring polishing machine. The angles of the four sides and the second end face are detected by a comparator. Based on the detection values, the second end face is polished at low speed to the first surface shape parameters, so that the second end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0023] Furthermore, after reinforcing the four sides with the positioning plate, the method further includes:

[0024] Yellow wax is filled into the gap between the optical component and the positioning plate.

[0025] Furthermore, after polishing the first end face and the second end face, the process further includes:

[0026] Chamfer the protective corners of the first end face and the second end face.

[0027] In some embodiments, the processing of the second side specifically includes:

[0028] Process the second side surface to the first surface shape parameters, control the edge thickness difference to be no greater than the first thickness threshold, control the included angle between the second side surface and the first side surface to be 90°, and control the angle error to be no greater than the first angle threshold.

[0029] Furthermore, the processing of the third side specifically includes:

[0030] Using the first side surface as a reference surface, the third side surface is processed to the first surface shape parameters, the edge thickness difference is controlled to be no greater than the first thickness threshold, and the third side surface and the first side surface are controlled to be parallel, with the parallelism error not greater than the first parallelism threshold.

[0031] In some embodiments, processing the fourth side specifically includes:

[0032] Using the second side as a reference plane, the fourth side is processed to the first surface shape parameters, controlling the edge thickness difference to be no greater than the first thickness threshold, and controlling the fourth side and the second side to be parallel, with the parallelism error no greater than the first parallelism threshold.

[0033] Furthermore, after processing the first side, the second side, the third side, and the fourth side, the method further includes: chamfering protective corners on the first side, the second side, the third side, and the fourth side.

[0034] The beneficial effects of the processing method and positioning fixture for large-size, high-precision optical components provided by this invention are at least as follows:

[0035] This processing method first processes the four sides of the optical component. When processing the first and second end faces, a specialized positioning fixture is used to stably position the optical component. The positioning fixture can stably support the four sides of the optical component, so that the large-sized optical component can be stably kept in a vertical position. Then, the first and second end faces are processed. Since the optical component can be stably supported by the positioning fixture, the stability of the first and second end faces during processing is improved, and high-precision processing of the first and second end faces is achieved. Thus, through a reasonable process flow and the design of a special end face processing fixture, large-sized, high-precision optical components can be processed using traditional optical cold working methods. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 A flowchart illustrating a method for processing large-size, high-precision optical components according to an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the structure of an optical component provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the positioning fixture provided in an embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the positioning plate provided in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the structure of the disk provided in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the structure of an optical component positioned within a positioning fixture according to an embodiment of the present invention.

[0043] The following are the labeling elements in the figure:

[0044] 1. Optical components;

[0045] 11. First side face; 12. Second side face; 13. Third side face; 14. Fourth side face; 15. First end face; 16. Second end face;

[0046] 2. Positioning fixtures;

[0047] 21. Disc; 211. Clearance hole;

[0048] 22. Positioning plate; 221. First plate; 222. Second plate; 223. Top surface; 224. Bottom surface; 225. Observation hole;

[0049] 23. Microcrystalline blocks. Detailed Implementation

[0050] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it may be directly or indirectly located on that other component. When a component is referred to as "connected to" another component, it may be directly or indirectly connected to that other component. The terms "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate orientations or positions based on the accompanying drawings, and are for ease of description only, and should not be construed as limiting the technical solution. 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. "A plurality" means two or more, unless otherwise explicitly defined.

[0052] To achieve the above objectives, a first aspect of the present invention provides a method for processing large-size, high-precision optical components. The method for processing large-size, high-precision optical components according to embodiments of the present invention will be described below with reference to the accompanying drawings.

[0053] First, some terms appearing in this implementation will be explained:

[0054] Surface shape: PV (Peak to Valley), also known as peak-to-valley value, is a common indicator of the surface shape quality of optical surfaces. It refers to the height difference between the highest and lowest points within a sampling range (based on 2D contour lines or 3D data maps), after removing the reference surface. PV values ​​are expressed in units of physical length, and their meaning is easy to understand. Based on the required reference surface, the maximum deviation range of all pixels directly reflects the current processing quality of the optical surface. Based on long-term experience in optical testing, PV values ​​and another important surface shape indicator, RMS, often maintain a certain proportional relationship, generally around 2:1.

[0055] Surface defects (smoothness): pits, scratches, marks, broken edges, and bubbles on the surface of optical products.

[0056] Edge thickness difference: The difference in thickness at the edges of a part.

[0057] See below. Figure 1 , Figure 1 A flowchart illustrating a method for processing large-size, high-precision optical components according to the present invention is provided. This method is used for processing large-size optical components. (Refer to...) Figure 2 The optical component 1 is cubic in shape and includes a first side surface 11, a second side surface 12, a third side surface 13, a fourth side surface 14 connected in sequence, and a first end surface 15 and a second end surface 16 disposed opposite to each other.

[0058] Understandably, during processing, a ring polishing machine is used to process large-sized optical components 1. However, during the processing, optical components 1 need to be erected, that is, the first end face 15 and the second end face 16 of optical components 1 need to be positioned above and below, respectively, before processing the first end face 15 and the second end face 16. However, due to the large size of optical components 1, after erecting them, optical components 1 are prone to wobbling and instability, which can easily lead to a deterioration in processing results. In other words, the parameters of the first end face 15 and the second end face 16 after processing may not meet the design requirements, and the safety and rationality of processing will be reduced. As a result, conventional processing methods cannot meet the processing requirements of large-sized optical components 1.

[0059] Therefore, in processing optical component 1, this processing method also uses a special positioning fixture 2, which is used to position the large-sized optical component 1 when processing the two end faces of the optical component 1 using a ring polishing machine. (See reference...) Figures 3-6 The positioning fixture 2 includes a disc 21, a positioning plate 22, and a microcrystalline block 23. The disc 21 has a clearance hole 211 in the center. The positioning plate 22 is detachably connected to the top of the disc 21. The microcrystalline block 23 protrudes from the bottom of the disc 21.

[0060] Continue reading Figure 1 The processing method for large-size, high-precision optical component 1 includes the following steps:

[0061] Step S1: Machin the first side 11, the second side 12, the third side 13, and the fourth side 14 to the first surface shape parameters;

[0062] Step S2: Apply protective adhesive to the four sides of the optical component 1, place the disc 21 on the platform, place the microcrystalline block 23 between the platform and the disc 21, place the second end face 16 of the optical component 1 downward into the clearance hole 211, and then install the positioning plate 22 onto the disc 21. The positioning plate 22 abuts against the first side 11, the second side 12, the third side 13 and the fourth side 14. Fill the gap between the optical component 1 and the positioning plate 22 with beeswax.

[0063] Step S3: Grind and polish the first end face 15 to the first surface shape parameters to ensure that the first end face 15 is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0064] Step S4: Place the first end face 15 downward into the clearance hole 211, and reinforce the four sides with the positioning plate 22;

[0065] Step S5: Following the method for processing the first end face 15, grind and polish the second end face 16 to the first surface shape parameters to ensure that the second end face 16 is parallel to the first end face 15 and the parallelism error is not greater than the first parallelism threshold.

[0066] Step S6: Remove the plate and clean the optical components 1.

[0067] This processing method first processes the four sides of the optical component 1. When processing the first end face 15 and the second end face 16, a special positioning fixture 2 is used to stably position the optical component 1. The positioning fixture 2 can stably support the four sides of the optical component 1, so that the large-sized optical component 1 can be stably kept in a vertical position. Then, the first end face 15 and the second end face 16 are processed. Since the optical component 1 can be stably supported by the positioning fixture 2, the stability of the first end face 15 and the second end face 16 during processing is improved, and high-precision processing of the first end face 15 and the second end face 16 is achieved. Thus, through a reasonable process flow and the design of a special end face processing fixture, the traditional optical cold working method can be used to process large-sized, high-precision optical components 1.

[0068] In some embodiments, the grinding and polishing of the first end face 15 to the first surface shape parameters specifically includes the following steps:

[0069] The optical component 1 and the first end face 15 are hand-grinded. Coarse sandpaper is used to remove the first dimension, and then fine sandpaper is used to remove the second dimension. While removing the dimension of the first end face 15, the tilt angle of the first end face 15 is continuously adjusted to ensure that the first end face 15 is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0070] The optical component 1 and the first end face 15 are polished as a whole. The third dimension is removed by high-speed polishing using a ring polishing device. The angles of the four sides and the first end face 15 are detected using a comparator. Based on the detection values, the first end face 15 is polished at low speed to the first surface shape parameters, so that the first end face 15 is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0071] Furthermore, based on the detected values, the low-speed polishing of the first end face 15 to the first surface shape parameters specifically includes:

[0072] When the detection value shows an acute angle, increase the polishing pressure on one side of the acute angle to remove more dimensions on that side.

[0073] When the detected value shows an obtuse angle, increase the polishing pressure on the side opposite to the acute angle.

[0074] Furthermore, following the method for processing the first end face 15, the second end face 16 is ground and polished to the first surface shape parameters, specifically including:

[0075] Hand-grind the positioning plate 22 and the second end face 16 as a whole, use coarse sandpaper to remove the first dimension, and then use fine sandpaper to remove the second dimension. While removing the dimension of the second end face 16, adjust the tilt angle of the second end face 16 to ensure that the second end face 16 is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0076] The positioning plate 22 and the second end face 16 are polished as a whole. The third dimension is removed by high-speed polishing with a ring polishing machine. The angles of the four sides and the second end face 16 are detected by a comparator. Based on the detection values, the second end face 16 is polished at low speed to the first surface shape parameters, so that the second end face 16 is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

[0077] Furthermore, after reinforcing the four sides with positioning plates 22, it also includes:

[0078] Yellow wax is filled into the gap between the optical component 1 and the positioning plate 22.

[0079] Furthermore, after polishing the first end face 15 and the second end face 16, the method further includes: chamfering the first end face 15 and the second end face 16 to protect the corners.

[0080] In some embodiments, the processing of the second side 12 specifically includes the following steps:

[0081] The second side 12 is processed to the first surface shape parameters, the edge thickness difference is controlled to be no greater than the first thickness threshold, the included angle between the second side 12 and the first side 11 is controlled to be 90°, and the angle error is no greater than the first angle threshold.

[0082] In some embodiments, the processing of the third side 13 specifically includes:

[0083] Using the first side surface 11 as a reference surface, process the third side surface 13 to the first surface shape parameters, control the edge thickness difference to be no greater than the first thickness threshold, control the third side surface 13 and the first side surface 11 to be parallel, and control the parallelism error to be no greater than the first parallelism threshold.

[0084] In some embodiments, the processing of the fourth side surface 14 specifically includes:

[0085] Using the second side surface 12 as a reference surface, process the fourth side surface 14 to the first surface shape parameters, control the edge thickness difference to be no greater than the first thickness threshold, control the fourth side surface 14 and the second side surface 12 to be parallel, and control the parallelism error to be no greater than the first parallelism threshold.

[0086] Furthermore, after processing the first side 11, the second side 12, the third side 13, and the fourth side 14, the method also includes: chamfering protective corners on the first side 11, the second side 12, the third side 13, and the fourth side 14.

[0087] In some embodiments, the positioning fixture 2 is used to position the optical component 1, see reference. Figure 2 The optical component 1 is cubic in shape and includes a first side surface 11, a second side surface 12, a third side surface 13, a fourth side surface 14 connected in sequence, and a first end surface 15 and a second end surface 16 disposed opposite to each other.

[0088] See Figures 3-6 The positioning fixture 2 can adopt the following structure: The positioning fixture 2 includes a disc 21, a positioning plate 22 and a microcrystalline block 23. The disc 21 is used to place on the platform. The center of the disc 21 is provided with a clearance hole 211 that is adapted to the size of the first end face 15 and the second end face 16. The optical component 1 is inserted into the clearance hole 211. The clearance hole 211 stops against the first side 11, the second side 12, the third side 13 and the fourth side 14.

[0089] See Figure 6 The positioning plate 22 is detachably connected to the upper surface of the disc 21, and the positioning plate 22 abuts against the first side 11, the second side 12, the third side 13 and the fourth side 14.

[0090] Microchip 23 protrudes from the bottom of disk 21 and is placed between disk 21 and platform to create a first gap between disk 21 and platform for accommodating optical component 1.

[0091] In some implementations, see Figures 3-6The positioning plate 22 includes a first plate 221 and a second plate 222 that are detachably connected. The first plate 221 is detachably mounted on the disk 21 by bolts. The second plate 222 includes a top surface 223 and a bottom surface 224 that are opposite to each other. The top surface 223 abuts against the first plate 221 and is fixed by bolts. The bottom surface 224 abuts against the side of the optical component 1 and is perpendicular to the upper surface of the disk 21. The second plate 222 is also provided with an observation hole 225 that penetrates the top surface 223 and the bottom surface 224.

[0092] Furthermore, the microcrystalline block 23 is fixed to the bottom of the disk 21 by silicone adhesive.

[0093] The following describes the processing method of a large-size, high-precision optical component 1 in the embodiment, with reference to an example. The finished product size to be processed is 350mm × 70mm × 70mm. All six surfaces of the optical component 1 are polished, and the surface shape PV of each surface is ≤1λ. The angle requirements are: the included angle between two adjacent surfaces = 90° ± 2″, the included angle between two opposite surfaces = 0° ± 2″, the surface finish is 40-20, and the material is microcrystalline. It should be noted that the surface shape detection mentioned in this invention is all performed using a 633nm laser. A ring polishing device is used for processing the first end surface 15 and the second end surface 16. Furthermore, the first angle threshold is 2″, the first parallelism threshold is 2″, the first dimension is 0.2mm, the second dimension is 0.08mm, the third dimension is 0.015mm, and the first thickness threshold is 0.005mm.

[0094] The processing flow is as follows:

[0095] (1) Machining the first side surface 11

[0096] Top plate: Place the parts to be processed symmetrically in the center on the glass plate with the first side 11 facing upwards. Then pour the melted yellow wax onto the plate. After the yellow wax solidifies, the parts to be processed can be fixed on the plate.

[0097] Sanding: Leave a 0.3mm machining allowance on each surface to be processed. During the processing, first use W40 (coarse sandpaper) to remove 0.2mm of the dimension, removing some large damage on the surface of the blank. Then use W14 (fine sandpaper) to remove 0.08mm of the dimension, removing the damage left by the coarse sandpaper and facilitating subsequent polishing.

[0098] Polishing: First, use a ring polishing high-pressure polishing machine to remove the 0.015mm dimension and the sand holes from the abrasive, making it easier for low-pressure polishing. After high-pressure polishing, use a ring polishing low-pressure polishing machine to remove the remaining 0.005mm dimension and refine the surface shape and smoothness.

[0099] Lower plate: Apply protective adhesive to the first side 11 to protect the polished surface. Use a frozen lower plate method to lower the plate, placing the entire tray of products in a freezer for refrigeration. Once the wax layer has deteriorated, the optical components 1 can be removed.

[0100] Chamfering: The first side has 11 chamfered corners to protect the parts from chipping due to impact.

[0101] Cleaning: Use Polyc to remove residual yellow wax from optical parts 1, and use acetone and ethanol to remove waterproof adhesive and other contaminants.

[0102] (2) Machining the second side 12

[0103] Upper plate: Since all adjacent surfaces have a 90° angle precision requirement, the included angle between the first side 11 and the second side 12 needs to be controlled at 90° ± 2″ when machining the second side 12. This step uses a cuboid to assist in machining. The 90° angle precision of the cuboid is already 2″, so this fixture can be used to correct the included angle between the first side 11 and the second side 12. First, apply optical adhesive to the first side 11 of the optical component 1 onto the cuboid, and then apply optical adhesive to the cuboid onto the adhesive tray.

[0104] Sanding: Use W40 (coarse sandpaper) to remove 0.2mm of the material, then use W14 (fine sandpaper) to remove 0.08mm of the material. During the sanding process, the edge thickness difference needs to be controlled; the deviation of the entire product should not exceed 0.005mm.

[0105] Polishing: First, use a high-impact ring polisher to remove the 0.015mm dimension and sand holes, facilitating low-impact polishing. After high-impact polishing, use a low-impact ring polisher to remove the remaining 0.005mm dimension and refine the surface shape and smoothness. During polishing, the edge thickness difference must be controlled to ≤0.005mm to avoid affecting the product's angles.

[0106] Lower plate: Apply protective adhesive to the polished surface to protect it. Remove the lower plate by tapping it, and remove optical component 1 from under the cuboid.

[0107] Chamfering: The second side has a 12-inch chamfer for protection, to prevent parts from chipping due to impact.

[0108] Cleaning: Use acetone and ethanol to remove waterproofing adhesive and other contaminants.

[0109] (3) Process the third side 13

[0110] Upper plate: The upper plate is made of glossy adhesive. The first side 11 is the glossy adhesive surface, and the third side 13 is the surface to be processed. Since the first side 11 and the second side 12 have already been processed, they can be used as reference surfaces to directly process the surfaces opposite to them.

[0111] Sanding: Use W40 (coarse sandpaper) to remove 0.2mm of the material, then use W14 (fine sandpaper) to remove 0.08mm of the material. During the sanding process, the edge thickness difference needs to be controlled; the deviation of the entire product should not exceed 0.005mm.

[0112] Polishing: First, use a high-impact ring polisher to remove the 0.015mm dimension and sand holes, facilitating low-impact polishing. After high-impact polishing, use a low-impact ring polisher to remove the remaining 0.005mm dimension and refine the surface shape and smoothness. During polishing, the edge thickness difference must be controlled to ≤0.005mm to avoid affecting the product's angles.

[0113] Lower plate: Apply protective glue to the polished surface, and tap and vibrate the lower plate after it dries.

[0114] Chamfer: 13 chamfered protective corner on the third side.

[0115] Cleaning: Use acetone and ethanol to clean.

[0116] (4) Process the fourth side 14

[0117] The machining process for the fourth side 14 is the same as that for the third side 13.

[0118] (5) Machining the first end face 15

[0119] Since the first end face 15 is processed using a ring polishing machine, the part needs to be vertically erected for sanding and polishing. However, due to the large size and high center of gravity of the optical part 1, direct processing is not reasonable. In response to the processing requirements, we designed a special positioning fixture 2.

[0120] The positioning fixture 2 is divided into three parts. The middle disc 21 is a cast iron disc with a diameter of 280mm. Its weight can lower the overall center of gravity during the processing. Above it are four detachable and assembleable positioning plates 22. In addition to the mounting screw holes, each positioning plate 22 also has a 50×60 observation hole 225 for inspection during the processing. At the bottom are eight microcrystalline blocks 23 bonded with silicone, which increases the polishing area and also provides support.

[0121] Upper plate:

[0122] Apply protective adhesive to the four sides of the processed optical component 1. After the adhesive dries completely, disassemble the upper plate tooling, place the disc 21 on the platform, and then put the optical component 1 to be processed into it with the first end face 15 facing down. Then assemble the four positioning plates 22. To ensure that the optical component 1 does not fall off during the processing, fill the gap between the optical component 1 and the positioning plate 22 with beeswax. After it cools and solidifies, the upper plate is complete.

[0123] Grinding: Hand-grind the optical component 1 and positioning plate 22 as a whole, using W40 (coarse sandpaper) to remove 0.2mm, and then using W14 (fine sandpaper) to remove 0.08mm. During the grinding process, manual angle adjustment is required. That is, while removing the dimension of the first end face 15, the tilt angle of the first end face 15 is continuously adjusted to ensure that the angle accuracy between the first end face 15 and the four already processed sides is within 10 seconds. This helps to control the angle accuracy in subsequent polishing.

[0124] Polishing: Polish the optical component 1 and positioning plate 22 as a whole. First, use a ring polishing high-polish equipment to remove 0.015mm. Use a comparator to check the angles of the four sides and the first end face 15 and record the data. Based on the actual values, refine the angles with low polishing. For acute angles, increase the pressure on the side to reduce the size on that side. For obtuse angles, increase the pressure on the opposite side. Simultaneously refine all four included angles to 90°±2″. Once the surface shape, angles, and smoothness are all qualified, it can be removed from the machine.

[0125] Lower plate: Apply protective glue to the machined surface, freeze the lower plate, put the positioning fixture 2 and optical component 1 into the freezer, freeze to deactivate the wax, then disassemble the positioning fixture 2 and remove the optical component 1.

[0126] Chamfer: The first end face has a 15° chamfer for protection.

[0127] Cleaning: Use Polycrystal to remove residual yellow wax from the parts, and use acetone and ethanol to remove waterproof adhesive and other contaminants.

[0128] (6) Machining the second end face 16

[0129] Upper plate: The method of upper plate is the same as that of the first end face 15. The first end face 15 is placed into the positioning fixture 2 with the first end face facing down and reinforced.

[0130] Grinding: Hand-grind the optical component 1 and positioning plate 22 as a whole, using W40 (coarse sandpaper) to remove 0.2mm, and then using W14 (fine sandpaper) to remove 0.08mm. During the grinding process, manual angle adjustment is required. That is, while removing the dimensions of the second end face 16, the tilt angle of the second end face 16 is continuously adjusted to ensure that the angular accuracy between the second end face 16 and the four already machined sides is within 10 seconds. This helps control the angular accuracy during subsequent polishing.

[0131] Polishing: Polish the optical component 1 and positioning plate 22 as a whole. First, use a high-pressure polishing machine to remove 0.015mm. Use a comparator to check the angles of the four sides and the second end face 16 and record the data. Based on the actual values, refine the angles with low-pressure polishing. For acute angles, increase pressure on the opposite side to reduce the dimension on that side. For obtuse angles, increase pressure on the opposite side to refine all four included angles to 90°±2″. Compared to the processing of the first end face 15, the parallelism of the second end face 16 with the first end face 15 also needs to be controlled. Process the second end face 16 according to the actual angle of the first end face 15 to ensure that the parallelism of the two end faces is within 2″. Once the surface shape, angles, and surface finish are all qualified, it can be removed from the machine.

[0132] Lower plate: Apply protective glue to the machined surface, freeze the lower plate, put the positioning fixture 2 and optical component 1 into the freezer, freeze to deactivate the wax, then disassemble the positioning fixture 2 and remove the optical component 1.

[0133] Chamfer: Chamfer a protective chamfer on the second end face.

[0134] Cleaning: Use Polycrystal to remove residual yellow wax from the parts, and use acetone and ethanol to remove waterproof adhesive and other contaminants.

[0135] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for processing large-size, high-precision optical components, characterized in that, The optical component is cubic in shape, including a first side, a second side, a third side, a fourth side connected in sequence, and a first end face and a second end face disposed opposite to each other; a positioning fixture is also provided, the positioning fixture including a disk, a positioning plate and a microcrystalline block, the disk having a clearance hole at its center, the positioning plate being detachably connected to the top of the disk, and the microcrystalline block being protruding from the bottom of the disk. The processing method includes: Process the first side surface, the second side surface, the third side surface, and the fourth side surface to the first surface shape parameters; Protective adhesive is applied to the four sides of the optical component. The disk is placed on the platform, and the microcrystalline block is placed between the platform and the disk. The second end face of the optical component is placed into the clearance hole, and then the positioning plate is installed on the disk. The positioning plate abuts against the first side, the second side, the third side, and the fourth side, thereby reinforcing the four sides. Grind and polish the first end face to the first surface shape parameters to ensure that the first end face is perpendicular to the four sides and that the angle error is not greater than the first angle threshold. Place the first end face down into the clearance hole, and reinforce the four sides with the positioning plate; Following the method for processing the first end face, the second end face is sanded and polished to the first surface shape parameter to ensure that the second end face is parallel to the first end face and the parallelism error is not greater than the first parallelism threshold. Remove the optical components from the tray and clean them.

2. The method for processing large-size, high-precision optical components according to claim 1, characterized in that, The grinding and polishing of the first end face to the first surface shape parameters specifically include: Hand-grind the positioning plate and the first end face as a whole, use coarse sandpaper to remove the first dimension, and then use fine sandpaper to remove the second dimension. While removing the first end face dimension, adjust the tilt angle of the first end face to ensure that the first end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold. The positioning plate and the first end face are polished as a whole. The third dimension is removed by high-speed polishing with a ring polishing machine. The angles of the four sides and the first end face are detected by a comparator. Based on the detection values, the first end face is polished at low speed to the first surface shape parameters, so that the first end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

3. The method for processing large-size, high-precision optical components according to claim 2, characterized in that, The step of polishing the first end face to the first surface shape parameters at low speed according to the detected value specifically includes: When the detection value shows an acute angle, increase the polishing pressure on one side of the acute angle to remove more dimensions on that side. When the detected value shows an obtuse angle, increase the polishing pressure on the side opposite to the acute angle.

4. The method for processing large-size, high-precision optical components according to any one of claims 1-3, characterized in that, The method for processing the first end face, specifically including grinding and polishing the second end face to the first surface shape parameters, includes: Hand-grind the positioning plate and the second end face as a whole. Use coarse sandpaper to remove the first dimension, and then use fine sandpaper to remove the second dimension. While removing the second end face dimension, adjust the tilt angle of the second end face to ensure that the second end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold. The positioning plate and the second end face are polished as a whole. The third dimension is removed by high-speed polishing with a ring polishing machine. The angles of the four sides and the second end face are detected by a comparator. Based on the detection values, the second end face is polished at low speed to the first surface shape parameters, so that the second end face is perpendicular to the four sides and the angle error is not greater than the first angle threshold.

5. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, After reinforcing the four sides with the positioning plate, the method further includes: Yellow wax is filled into the gap between the optical component and the positioning plate.

6. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, After polishing the first end face and the second end face, the process further includes: Chamfer the protective corners of the first end face and the second end face.

7. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, The processing of the second side specifically includes: Process the second side surface to the first surface shape parameters, control the edge thickness difference to be no greater than the first thickness threshold, control the included angle between the second side surface and the first side surface to be 90°, and control the angle error to be no greater than the first angle threshold.

8. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, The processing of the third side specifically includes: Using the first side surface as a reference surface, the third side surface is processed to the first surface shape parameters, the edge thickness difference is controlled to be no greater than the first thickness threshold, and the third side surface and the first side surface are controlled to be parallel, with the parallelism error not greater than the first parallelism threshold.

9. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, The processing of the fourth side specifically includes: Using the second side as a reference plane, the fourth side is processed to the first surface shape parameters, controlling the edge thickness difference to be no greater than the first thickness threshold, and controlling the fourth side and the second side to be parallel, with the parallelism error no greater than the first parallelism threshold.

10. The method for processing large-size, high-precision optical components according to claim 4, characterized in that, After processing the first side, the second side, the third side, and the fourth side, the process further includes: chamfering protective corners on the first side, the second side, the third side, and the fourth side.

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