Cylindrical lens processing device and processing method

Abstract

The invention discloses a processing device and a processing method for a cylindrical lens, comprising a convex surface processing component for processing a curvature surface of the cylindrical lens, and a plane processing component for processing a plane surface of the cylindrical lens, wherein the convex surface processing component comprises a fixing fixture for fixing the cylindrical lens, a fine grinding mold for fine grinding the curvature surface of the cylindrical lens, and a polishing mold for polishing the curvature surface of the cylindrical lens; a matching piece for assisting in processing the curvature surface of the cylindrical lens is arranged at the periphery of the cylindrical lens, the matching piece is arranged along the surface of the fixing fixture, and the surface of the matching piece matches the surface of the cylinder where the curvature surface of the cylindrical lens is located; the invention arranges the matching piece at the periphery of the cylindrical lens to assist in processing, thereby increasing the overall processed area, improving the contact stability between the cylindrical lens and the corresponding working surfaces of the fine grinding mold and the polishing mold, improving the surface shape accuracy of the entire cylindrical lens, and thus ensuring the surface shape accuracy of the cylindrical lens located in the central area.

Description

Technical Field

[0001] The present invention relates to the technical field of lens processing, and in particular to a processing device and a processing method for a cylindrical lens. Background Art

[0002] In recent years, cylindrical optical elements have been widely used in high-power optical systems to achieve functions such as laser beam shaping and beam expansion. Common ones include biconvex cylinders, plano-convex cylinders, biconcave cylinders, plano-concave cylinders, etc. As the beam quality required by laser systems increases, laser systems have higher and higher requirements for cylindrical optical elements. They not only require the surface accuracy of the cylinder, but also need to strictly control the geometric accuracy error of the cylinder, including the parallelism error of the upper and lower surface generatrix of the cylinder, and the eccentricity of the cylinder. The parallelism error of the upper and lower surface generatrix of the cylinder includes: transverse parallelism and longitudinal parallelism. The transverse parallelism causes the upper and lower surfaces to rotate around the optical axis. Rotation, resulting in a large astigmatism error, and the longitudinal parallelism leads to inconsistent thickness of the cylinder, resulting in a tilt error of the light beam, and the cylindrical surface error has a great influence. Therefore, the generatrix parallelism of the cylinder, the surface accuracy, etc. need to be strictly controlled during processing, especially the processing method of the traditional plano-convex cylindrical mirror is four stages: cylindrical rough grinding and forming, cylindrical fine grinding, cylindrical rough polishing, and cylindrical fine polishing and shaping, and parameter control is performed in each process. The accuracy of the obtained plano-convex cylinder is limited by the accuracy of the processing machine and the mold itself. Generally, it is difficult to directly achieve the geometric shape of the cylindrical lens through the processing of a single cylindrical lens, and the surface shape has higher accuracy. Summary of the invention

[0003] Technical purpose: In view of the above-mentioned deficiencies in the existing cylindrical lens processing, the present invention discloses a cylindrical lens processing device and a method that can eliminate the influence of the processing machine and the accuracy of the mold itself on the geometric accuracy and surface accuracy of the plano-convex lens, thereby improving the processing accuracy.

[0004] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0005] A cylindrical lens processing device comprises a convex surface processing component for processing the curvature surface of the cylindrical lens, and a plane processing component for processing the plane surface of the cylindrical lens, wherein the convex surface processing component comprises a fixing jig for fixing the cylindrical lens, a fine grinding mold for fine grinding the curvature surface of the cylindrical lens, and a polishing mold for polishing the curvature surface of the cylindrical lens; the curvature of the fixing jig is smaller than the curvature of the curvature surface of the cylindrical lens, and the curvatures of the processing surfaces of the fine grinding mold and the polishing mold both match the cylindrical lens; a matching piece for assisting the processing of the curvature surface of the cylindrical lens is arranged on the periphery of the cylindrical lens, the matching piece is arranged along the surface of the fixing jig, and the surface of the matching piece matches the surface of the cylinder where the curvature surface of the cylindrical lens is located.

[0006] Preferably, the fine grinding mold and polishing mold of the present invention are provided with an assembly hole that cooperates with the pressure head of the fine grinding machine on the other side opposite to their own processing surface, and the fine grinding mold and polishing mold are installed and disassembled on the fine grinding machine through the cooperation between the assembly hole and the pressure head.

[0007] Preferably, the plane processing assembly of the present invention includes a groove fixture for clamping a cylindrical lens, and a plane fine grinding tool and a plane polishing tool for performing plane processing of the cylindrical lens are arranged below the groove fixture. The lower parts of the plane fine grinding tool and the plane polishing tool are connected to the rotating end of the fine grinder through a concentric connecting shaft to perform fine grinding and polishing of the cylindrical lens plane.

[0008] Preferably, the groove fixture of the present invention is provided with a groove matching the curvature surface of the cylindrical lens, the plane of the cylindrical lens protrudes from the surface of the groove fixture, and a pressure iron for providing pressure for fine grinding and polishing the plane of the cylindrical lens is provided on the bottom surface of the groove fixture.

[0009] The present invention discloses a cylindrical lens processing method, using the above-mentioned cylindrical lens processing device, characterized in that the size of the cylindrical lens blank is selected according to the size and processing accuracy of the cylindrical lens; a convex surface processing component is used to process the curvature surface of the cylindrical lens, and then a plane processing component is used to process the plane of the cylindrical lens, and finally the shape of the cylindrical lens is trimmed to obtain a cylindrical lens that meets the requirements.

[0010] Preferably, the process of selecting the size of the cylindrical lens blank of the present invention includes: the length of the cylindrical lens is L1, the width is L2, the thickness is d, the cylindrical curvature is R, and the center deviation is X; the circumscribed circle diameter of the cylindrical lens plane is calculated according to the size of the cylindrical lens; the maximum center deviation of the cylindrical lens is converted into the maximum allowable edge thickness difference, and the imaginary circumscribed circle diameter D1 of the processed cylindrical lens is calculated according to the accuracy of the cylindrical edge thickness difference processed by the fine grinding machine, and the length L3 of the cylindrical lens blank is confirmed according to the processing allowance requirement in the direction of the cylindrical lens generatrix, and then the width L4 of the cylindrical lens blank is determined by the imaginary circumscribed circle diameter D1 and L3.

[0011] Preferably, the process of using a convex surface processing component to process the curvature surface of a cylindrical lens in the present invention includes: bonding and fixing the selected cylindrical lens blank on the curvature surface of a fixed jig and placing it in the central area of ​​the fixed jig, fixing the matching lenses on the surface of the fixed jig at intervals along the periphery of the cylindrical lens blank, the fixed jig drives the cylindrical lens to reciprocate along the generatrix direction of the cylinder, and at the same time using a fine grinder to drive the fine grinding mold and the polishing mold to reciprocate along the curvature direction of the fixed jig to complete the processing of the curvature surface of the cylindrical lens.

[0012] Preferably, the process of using a plane processing assembly to perform plane processing on a cylindrical lens in the present invention includes: using a groove fixture to clamp the cylindrical lens so that the plane of the cylindrical lens faces the corresponding mold, and arranging a hollow cylindrical fixture on the outer periphery of the groove fixture to maintain a stable position of the groove fixture on the mold, the inner periphery of the hollow cylindrical fixture matches the circumscribed circle of the contour of the groove fixture, and providing pressure for the plane processing of the cylindrical lens by a pressure iron.

[0013] Preferably, the process of trimming the appearance of the cylindrical lens of the present invention includes: concentrically clamping and fixing the cylindrical lens on the grinding tool, the clamping area is smaller than the required cylindrical lens size, taking the center of the cylindrical lens as the processing center, and performing edge grinding processing from large to small according to the diameter range of the circumscribed circle of the cylindrical lens until the diameter of the circumscribed circle of the cylindrical lens meets the processing requirements, and then trimming the two sides according to the width requirements of the cylindrical lens.

[0014] Beneficial effects: The cylindrical lens processing device and processing method provided by the present invention have the following beneficial effects:

[0015] 1. When processing a cylindrical lens, the present invention arranges a matching lens on the periphery of the cylindrical lens to assist in processing, which can increase the overall processing area, improve the contact stability between the cylindrical lens and the corresponding fine grinding mold and polishing mold working surface, improve the surface accuracy of the entire cylindrical lens, and thus ensure the surface accuracy of the cylindrical lens located in the central area.

[0016] 2. The present invention selects the size of the cylindrical lens blank to be processed based on the processing accuracy of the fine grinder itself, thereby ensuring that the precision of the processed cylindrical lens meets the requirements, and there is no need to use equipment that meets specific processing accuracy requirements, thereby reducing processing costs; at the same time, the processing accuracy is guaranteed by increasing the width of the curvature surface of the cylindrical lens. After the processing is completed, the cylindrical lens that meets the requirements can be directly processed by concentric edge grinding, without considering the influence of the generatrix deviation caused by the processing on the lens size. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0018] Figure 1 A schematic diagram of fine grinding of the curvature surface of the cylindrical lens of the present invention;

[0019] Figure 2 A schematic diagram of the curvature surface polishing process of the cylindrical lens of the present invention;

[0020] Figure 3 A schematic diagram of the planar fine grinding process of the cylindrical lens of the present invention;

[0021] Figure 4A schematic diagram of a planar polishing process for a cylindrical lens of the present invention;

[0022] Figure 5 It is a schematic diagram of the orthographic projection of the cylindrical lens of the present invention;

[0023] Figure 6 This is a schematic diagram of confirming the size of a cylindrical lens blank according to the machining accuracy of a fine grinding machine in the present invention;

[0024] Among them, 1- cylindrical lens, 2- fixing fixture, 3- fine grinding mold, 4- polishing mold, 5- matching lens, 6- pressure head, 7- assembly hole, 8- groove fixture, 9- flat fine grinding mold, 10- flat polishing mold, 11- pressure iron, 12- hollow cylindrical fixture. DETAILED DESCRIPTION

[0025] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by explaining the apparatus, composition and materials of the present disclosure, rather than limiting. On the contrary, the following description provides a convenient illustration of an exemplary embodiment for implementing the present disclosure. In fact, it will be clear to those skilled in the art that various modifications and variations can be made in the teachings of the present disclosure without departing from the scope or spirit of the present disclosure. For example, a feature shown or described as a part of an embodiment can be used in conjunction with another embodiment to produce yet another embodiment. It is expected that the present disclosure covers such modifications and variations within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present disclosure are disclosed in or clear from the following detailed description. It will be understood by those of ordinary skill in the art that this discussion is only a description of exemplary embodiments and is not intended to limit the wider aspects of the present disclosure.

[0026] like Figure 1-Figure 4 The figure shows a cylindrical lens processing device disclosed in the present invention, comprising a convex surface processing component for processing the curvature surface of the cylindrical lens 1, and a plane processing component for processing the plane of the cylindrical lens 1, wherein the convex surface processing component comprises a fixing fixture 2 for fixing the cylindrical lens, a fine grinding mold 3 for fine grinding the curvature surface of the cylindrical lens 1, and a polishing mold 4 for polishing the curvature surface of the cylindrical lens 1; the curvature of the fixing fixture 2 is smaller than the curvature of the curvature surface of the cylindrical lens 1, and the curvatures of the processing surfaces of the fine grinding mold 3 and the polishing mold 4 are both matched with the cylindrical lens 1; a matching piece 5 for assisting in processing the curvature surface of the cylindrical lens 1 is arranged on the periphery of the cylindrical lens 1, the matching piece 5 is arranged along the surface of the fixing fixture 2, the surface of the matching piece 5 matches the cylindrical surface where the curvature surface of the cylindrical lens 1 is located, and the curvature can be slightly smaller than the curvature of the cylindrical lens 1, so that when the cylindrical lens 1 is processed, the matching piece is processed synchronously.

[0027] When processing cylindrical lenses, a fine grinder with a processing area larger than the required cylindrical lens size is selected. Under the condition of the same processing accuracy of the fine grinder, the larger the processing area, the higher the surface accuracy of the local area, thereby achieving the purpose of using the same fine grinder to process cylindrical lenses with different surface accuracy according to different processing sizes.

[0028] The matching piece 5 on the periphery of the cylindrical lens 1 can supplement the free area on the surface of the fixed fixture 2, thereby ensuring that the fine grinding die 3 and the polishing die 4 of the fine grinder maintain the stability of the contact surface with the cylindrical lens 1 during processing, ensuring the surface accuracy of the overall processed surface, and thus making the precision of the processed cylindrical lens 1 meet the requirements.

[0029] The fine grinding die 3 and the polishing die 4 of the present invention are provided with an assembly hole 7 which cooperates with the pressure head 6 of the fine grinding machine on the other side opposite to their own processing surface. The assembly hole 7 cooperates with the pressure head 6 to realize the installation and disassembly of the fine grinding die 3 and the polishing die 4 on the fine grinding machine.

[0030] In a specific embodiment, the plane processing assembly of the present invention includes a groove fixture 8 for clamping a cylindrical lens 1, and a plane fine grinding tool 9 and a plane polishing tool 10 are arranged below the groove fixture 8 for performing plane processing of the cylindrical lens 1. The lower parts of the plane fine grinding tool 9 and the plane polishing tool 10 are connected to the rotating end of the fine grinder through a concentric connecting shaft to perform fine grinding and polishing of the plane of the cylindrical lens 1.

[0031] In order to achieve accurate clamping of the cylindrical lens and ensure the stability of the position of the cylindrical lens during processing, the groove fixture 8 of the present invention is provided with a groove matching the curvature surface of the cylindrical lens 1, the plane of the cylindrical lens 1 protrudes from the surface of the groove fixture 8, and a pressure iron 11 for providing pressure for fine grinding and polishing of the plane of the cylindrical lens 1 is provided on the bottom surface of the groove fixture 8; a hollow cylindrical fixture 12 can also be provided on the outer side of the groove fixture 8 to maintain it on the corresponding mold surface, and the hollow cylindrical fixture 12 is provided with an inner hole matching the circumscribed circle of the groove fixture 8, so that the position of the groove fixture 8 on the mold can be kept stable by the hollow cylindrical fixture 12, and the friction force generated by the relative movement between the mold and the cylindrical lens 1 is used to perform fine grinding and polishing of the plane of the cylindrical lens.

[0032] The present invention also discloses a cylindrical lens processing method, which uses the above-mentioned cylindrical lens processing device to select the size of the cylindrical lens blank according to the size and processing accuracy of the cylindrical lens; uses a convex surface processing component to process the curvature surface of the cylindrical lens, and then uses a plane processing component to process the plane of the cylindrical lens, and finally trims the shape of the cylindrical lens to obtain a cylindrical lens that meets the requirements.

[0033] The process of selecting the size of a cylindrical lens blank of the present invention comprises: the length of the cylindrical lens is L1, the width is L2, the thickness is d, the cylindrical curvature is R, and the center deviation is X; the circumscribed circle diameter of the cylindrical lens plane is calculated according to the size of the cylindrical lens; the maximum center deviation of the cylindrical lens is converted into the maximum allowable edge thickness difference, the imaginary circumscribed circle diameter D1 of the processed cylindrical lens is calculated according to the accuracy of the cylinder edge thickness difference processed by a fine grinding machine, the length L3 of the cylindrical lens blank is confirmed according to the processing allowance requirement in the direction of the cylindrical lens generatrix, and the width L4 of the cylindrical lens blank is determined by the imaginary circumscribed circle diameter D1 and L3.

[0034] The process of using a convex surface processing component to process the curvature surface of a cylindrical lens in the present invention includes: bonding and fixing a selected cylindrical lens blank on the curvature surface of a fixed fixture and placing it in the central area of ​​the fixed fixture, fixing matching lenses on the surface of the fixed fixture at intervals along the outer periphery of the cylindrical lens blank, the fixed fixture drives the cylindrical lens to reciprocate along the generatrix direction of the cylinder, and at the same time, using a fine grinder to drive a fine grinding mold and a polishing mold to reciprocate along the curvature direction of the fixed fixture to complete the processing of the curvature surface of the cylindrical lens.

[0035] The process of using a plane processing component to perform plane processing on a cylindrical lens of the present invention includes: using a groove clamp to clamp the cylindrical lens so that the plane of the cylindrical lens faces the corresponding mold, arranging a hollow cylindrical clamp on the outer periphery of the groove clamp to keep the position of the groove clamp on the mold stable, the inner periphery of the hollow cylindrical clamp matches the circumscribed circle of the contour of the groove clamp, and providing pressure for the plane processing of the cylindrical lens by a pressure iron.

[0036] The process of trimming the appearance of a cylindrical lens of the present invention comprises: concentrically clamping and fixing the cylindrical lens on a grinder, wherein the clamping area is smaller than the required cylindrical lens size, taking the center of the cylindrical lens as the processing center, performing edge grinding processing according to the diameter range of the circumscribed circle of the cylindrical lens from large to small, until the diameter of the circumscribed circle of the cylindrical lens meets the processing requirements, and then trimming the two sides according to the width requirements of the cylindrical lens.

[0037] According to the above method steps, a cylindrical lens that meets the requirements can be processed based on the processing device provided by the present invention.

[0038] The processing method of the present invention is further described below with reference to a specific embodiment.

[0039] The dimensions of the cylindrical lens are: L1=120mm, L2=100mm, thickness d=20, cylindrical curvature R=400, center deviation X is 1 point, and the refractive index of material K9 is 1.5168.

[0040] The diameter of the circumscribed circle of the projection can be calculated based on the size of the cylindrical lens. ,like Figure 5 shown.

[0041] According to the eccentricity conversion formula: , where C is the linear value, n is the refractive index of the cylindrical lens material, is the image vertex focal length, and substituting the cylindrical lens parameters into the value, we obtain: C=0.1164.

[0042] Convert the center deviation linear value into edge thickness difference to obtain the maximum allowable edge thickness difference of cylindrical lens processing: , the edge thickness difference is 0.045mm.

[0043] The processing capacity of the fine grinder selected in the present invention can process a lens with an edge thickness difference of 0.075mm, which does not meet the processing requirements of cylindrical lenses. In order to realize the processing of cylindrical lenses, it is necessary to substitute the processing capacity of the fine grinder into the edge thickness difference formula based on the calculated edge thickness difference of the cylindrical lens, and the required lens projection circumscribed circle diameter D1=262.06mm can be obtained; at the same time, since a 1mm glass broken edge margin needs to be reserved in the generatrix direction of the cylindrical lens, L3=120+1=121mm, and the corresponding L4=232.45mm.

[0044] The selected cylindrical lens blank size is recorded as the numerical size of L3 and L4. After selection, the processing device is directly used to process the curvature surface and the plane. After the processing is completed, since the width direction of the cylindrical lens blank is larger than the required size, it needs to be trimmed to meet the requirements.

[0045] In order to quickly perform trimming and improve efficiency, the present invention directly uses an edge grinder to grind the cylindrical lens in steps from large to small diameters. During the grinding process, since the center of the cylindrical lens is used as the grinding center, as the grinding proceeds, the generatrix deviation caused by the processing will also be removed. When the circumscribed circle size D of the required cylindrical lens is ground, the arc surfaces on both sides of the cylindrical lens are cut and processed to obtain a finished cylindrical lens.

Claims

1. A method for processing a cylindrical lens, using a cylindrical lens processing device to process a cylindrical lens, characterized in that: The cylindrical lens processing device comprises a convex surface processing component for processing the curvature surface of the cylindrical lens (1), and a plane processing component for processing the plane of the cylindrical lens (1); the convex surface processing component comprises a fixing jig (2) for fixing the cylindrical lens, a fine grinding mold (3) for fine grinding the curvature surface of the cylindrical lens (1), and a polishing mold (4) for polishing the curvature surface of the cylindrical lens (1); the curvature of the fixing jig (2) is smaller than the curvature of the curvature surface of the cylindrical lens (1), and the curvatures of the processing surfaces of the fine grinding mold (3) and the polishing mold (4) both match the cylindrical lens (1); a matching piece (5) for assisting in processing the curvature surface of the cylindrical lens (1) is arranged on the periphery of the cylindrical lens (1); the matching piece (5) is arranged along the surface of the fixing jig (2), and the surface of the matching piece (5) matches the surface of the cylinder where the curvature surface of the cylindrical lens (1) is located; The plane processing assembly comprises a groove fixture (8) for clamping the cylindrical lens (1), a plane fine grinding tool (9) and a plane polishing tool (10) arranged below the groove fixture (8) for performing plane processing on the cylindrical lens (1), wherein the lower parts of the plane fine grinding tool (9) and the plane polishing tool (10) are connected to the rotating end of the fine grinding machine via a concentric connecting shaft, so as to perform fine grinding and polishing on the plane of the cylindrical lens (1); The groove fixture (8) is provided with a groove matching the curvature surface of the cylindrical lens (1); the plane of the cylindrical lens (1) protrudes from the surface of the groove fixture (8); and a pressure iron (11) for providing fine grinding and polishing pressure for the plane of the cylindrical lens (1) is provided on the bottom surface of the groove fixture (8); The processing method comprises: selecting the size of the cylindrical lens blank according to the size and processing accuracy of the cylindrical lens; processing the curvature surface of the cylindrical lens using a convex surface processing component, then processing the plane of the cylindrical lens using a plane processing component, and finally trimming the shape of the cylindrical lens to obtain a cylindrical lens that meets the requirements; The process of selecting the size of the cylindrical lens blank includes: the length of the cylindrical lens is L1, the width is L2, the thickness is d, the cylindrical curvature is R, and the center deviation is X; the circumscribed circle diameter of the cylindrical lens plane is calculated according to the size of the cylindrical lens; the maximum center deviation of the cylindrical lens is converted into the maximum allowable edge thickness difference, and the imaginary circumscribed circle diameter D1 of the processed cylindrical lens is calculated according to the accuracy of the cylindrical edge thickness difference processed by the fine grinding machine, and the length L3 of the cylindrical lens blank is confirmed according to the processing allowance requirement in the direction of the cylindrical lens generatrix, and then the width L4 of the cylindrical lens blank is determined by the imaginary circumscribed circle diameter D1 and L3.

2. A cylindrical lens processing method according to claim 1, characterized in that: The fine grinding die (3) and the polishing die (4) are provided with an assembly hole (7) that cooperates with a pressure head (6) of the fine grinding machine on the other side opposite to the processing surface thereof, and the fine grinding die (3) and the polishing die (4) are installed and removed from the fine grinding machine by cooperating with the pressure head (6) through the assembly hole (7).

3. A cylindrical lens processing method according to claim 1, characterized in that: The process of using a convex surface processing component to process the curvature surface of a cylindrical lens includes: bonding and fixing the selected cylindrical lens blank on the curvature surface of a fixed fixture and placing it in the central area of ​​the fixed fixture, fixing the matching lenses on the surface of the fixed fixture at intervals along the outer periphery of the cylindrical lens blank, the fixed fixture drives the cylindrical lens to reciprocate along the generatrix direction of the cylinder, and at the same time, using a fine grinder to drive the fine grinding mold and the polishing mold to reciprocate along the curvature direction of the fixed fixture to complete the processing of the curvature surface of the cylindrical lens.

4. The cylindrical lens processing method according to claim 1, characterized in that: The process of using a plane processing component to perform plane processing on a cylindrical lens includes: using a groove fixture to clamp the cylindrical lens so that the plane of the cylindrical lens faces the corresponding mold, and arranging a hollow cylindrical fixture on the outer periphery of the groove fixture to keep the position of the groove fixture on the mold stable. The inner periphery of the hollow cylindrical fixture matches the circumscribed circle of the contour of the groove fixture, and pressure for the plane processing of the cylindrical lens is provided by a pressure iron.

5. The cylindrical lens processing method according to claim 1, characterized in that: The process of trimming the shape of the cylindrical lens includes: concentrically clamping the cylindrical lens on the mold, with the clamping area smaller than the required cylindrical lens size, taking the center of the cylindrical lens as the processing center, and performing edge grinding from large to small according to the diameter range of the circumscribed circle of the cylindrical lens until the diameter of the circumscribed circle of the cylindrical lens meets the processing requirements, and then trimming the sides according to the width requirements of the cylindrical lens.

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