A method and device for processing special-shaped lenses

Abstract

The invention discloses a method and a device for processing a special-shaped lens. The edge of the special-shaped lens is provided with a circular arc-shaped concave curvature surface and a convex curvature surface. The curvature of the grinding wheel required for processing is determined according to the curvatures of the concave curvature surface and the convex curvature surface of the special-shaped lens, and the middle diameter of the grinding wheel is determined according to the thickness value of the processing area at the farthest position from the central axis of the grinding wheel. The grinding wheel shape is confirmed according to the middle diameter value and the curvature value of the grinding wheel. The determined grinding wheel is used to perform cutting processing on the edge of the special-shaped lens. For a continuous edge contour of the lens, the grinding wheel adopts an integrated structure matching the continuous length of the profile line, and the concave curvature surface and the convex curvature surface are processed synchronously. The invention realizes high-precision cutting processing of the lens by using a grinding wheel matching the convex and concave curvature surfaces of the lens edge to perform grinding processing on the lens, thereby ensuring the consistency of the processing curvature and ensuring the quality requirements of the finished lens.

Description

Technical Field

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

[0002] In the field of aerospace applications, high-end lenses need to have a small size and weight in addition to good optical performance. The edges of the lenses and related clamping components inside the lenses have arc-shaped grooves and convex grooves to adapt to other adjacent structural components and compact structural space. At the same time, a highly stable positional relationship between components is achieved to achieve overall weight reduction and highly stable assembly between components. The edge arc grooves of the lenses inside the lens have specific geometric dimensions and other precision and consistency requirements. At present, the processing of the arc grooves and convex grooves on the edges of the lenses has problems of low precision consistency or low efficiency. At the same time, complex equipment is generally required to process the grooves and convex grooves of the lenses. In addition, due to the accuracy differences in machine control, the accuracy consistency of the finished lenses is difficult to guarantee. Summary of the invention

[0003] Technical purpose: In view of the shortcomings of the above-mentioned existing lens edge cutting processing, the present invention discloses a special-shaped lens processing method and processing device that can ensure processing consistency and improve lens processing quality.

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

[0005] A method for processing a special-shaped lens, wherein the edge of the special-shaped lens is provided with an arc-shaped concave curvature surface and a convex curvature surface, the curvature of a grinding wheel required for processing is determined according to the curvatures of the concave curvature surface and the convex curvature surface of the special-shaped lens, the middle diameter of the grinding wheel is determined according to the thickness value of the lens processing area at the farthest position from the grinding wheel center axis, the grinding wheel shape is confirmed according to the middle diameter value of the grinding wheel and the curvature value of the corresponding processed curvature surface, the determined grinding wheel is used to perform cutting processing on the edge of the special-shaped lens, and for a continuous lens edge contour, the grinding wheel adopts an integrated structure that matches the continuous length of the profile line, and the concave curvature surface and the convex curvature surface are processed simultaneously.

[0006] Preferably, the process of determining the thickness value of the lens processing area at the position farthest from the grinding wheel center axis of the present invention comprises the steps of:

[0007] S01. Draw a lens projection plane diagram according to the required parameters of the finished product of the special-shaped lens;

[0008] S02, fitting a virtual complete circle corresponding to the concave curvature surface and the convex curvature surface on the projection plane according to the concave curvature surface and the convex curvature surface to be processed on the lens;

[0009] S03, confirming the relative position coordinates of the center of the virtual complete circle on the lens and calibrating it;

[0010] S04, determining the coordinates of the points on the arcs of the corresponding concave curvature surface and convex curvature surface that are farthest from the grinding wheel axis according to the relative position coordinates;

[0011] S05. Determine the thickness value of the lens corresponding to the corresponding position according to the coordinate value.

[0012] Preferably, the process of determining the median diameter of the grinding wheel according to the thickness value of the present invention comprises: setting the curvature of the edge of the lens along the thickness direction when the grinding wheel processes the lens , according to the curvature And the thickness value h is used to calculate the grinding wheel median diameter r, .

[0013] Preferably, for the continuous convex and concave curvature surfaces on the edge of the special-shaped lens, the present invention takes the calculated center diameter of the grinding wheel as the center, designs the curvature of the grinding wheel surface according to the curvature of the corresponding curvature surface, and the grinding wheels corresponding to adjacent curvature surfaces are connected end to end as a whole, so that during processing, the processing of all continuous curvature surfaces is completed synchronously.

[0014] Preferably, when confirming the middle diameters of multiple grinding wheels, the present invention first establishes a basic grinding wheel model according to the number of grinding wheels and the corresponding curvature surface sizes, and first determines the middle diameter size corresponding to the smallest diameter grinding wheel. Then, the remaining grinding wheels are magnified according to the relative position relationship of the curvature surface corresponding to the smallest diameter grinding wheel on the projection plane, and the middle diameter value of the processing grinding wheel required for each curvature surface of the lens is obtained.

[0015] Preferably, after obtaining the mean diameter values ​​of all grinding wheels, the present invention establishes a lens model according to the surface curvature of the special-shaped lens, calculates the curvature caused by the mean diameter of the grinding wheel at the position with the maximum processing thickness on the lens, and corrects the mean diameter value of the grinding wheel at this position according to the calculation result; the mean diameter values ​​of the grinding wheel at other positions are adjusted synchronously.

[0016] The invention discloses a device for processing special-shaped lenses, which uses the above-mentioned processing method and comprises a clamping fixture for clamping the lens and a grinding machine for cutting the curvature surface of the edge of the lens, wherein the grinding wheel of the grinding machine has a processing curvature surface matching the curvature surface of the lens.

[0017] Preferably, the clamping fixture of the present invention is a T-shaped structure, and a groove for accommodating the lens is provided at the end with a larger diameter. After the lens is installed in the groove, beeswax is provided between the gap between the lens and the groove for fixing.

[0018] Preferably, the clamping fixture of the present invention is made of stainless steel.

[0019] Preferably, after the lens of the present invention is fixed on the clamping fixture, the line connecting the centers of the edges of the curvature surfaces of the processed side lens is parallel to the axis of the grinding wheel, and the cutting position of the lens is located outside the groove.

[0020] Beneficial effects: The method and device for processing special-shaped lenses provided by the present invention have the following beneficial effects:

[0021] 1. The present invention uses a grinding wheel that matches the convex and concave curvature surfaces of the lens edge to grind the lens, thereby achieving high-precision cutting of the lens, ensuring the consistency of the processing curvature, and ensuring the quality requirements of the finished lens.

[0022] 2. The present invention confirms the center coordinates of the curvature surface of the lens by projection, and can use this to locate the edge position when the grinding wheel is processing, so that the curvature of the curvature surface processed by the grinding wheel in the thickness direction of the lens meets the requirements, ensuring the processing accuracy of the edge of the lens and avoiding excessive curvature that affects the quality of the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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.

[0024] Figure 1 This is a schematic diagram of using a grinding wheel to process a lens in the present invention;

[0025] Figure 2 This is a schematic diagram of the lens structure in an embodiment of the present invention;

[0026] Figure 3 A schematic diagram of determining the thickness of a lens according to a projection plane diagram of the lens according to the present invention;

[0027] Figure 4 It is a schematic diagram of the grinding wheel structure of the present invention;

[0028] Among them, 1-lens, 2-clamping fixture, 3-grinding wheel, 4-groove. DETAILED DESCRIPTION

[0029] 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.

[0030] like Figure 1-Figure 4 As shown, the present invention discloses a method for processing a special-shaped lens, wherein the edge of the special-shaped lens is provided with a circular arc-shaped concave curvature surface and a convex curvature surface, the curvature of the grinding wheel required for processing is determined according to the curvatures of the concave curvature surface and the convex curvature surface of the special-shaped lens, and the middle diameter of the grinding wheel is determined according to the thickness value of the lens processing area at the farthest position from the grinding wheel center axis, the grinding wheel shape is confirmed according to the middle diameter value of the grinding wheel and the curvature value of the corresponding processed curvature surface, and the determined grinding wheel is used to perform cutting processing on the edge of the special-shaped lens. For a continuous lens edge contour, the grinding wheel adopts an integrated structure that matches the continuous length of the mold line, and the concave curvature surface and the convex curvature surface are processed simultaneously.

[0031] The process of determining the thickness value of the lens processing area at the position farthest from the center axis of the grinding wheel comprises the following steps:

[0032] S01. Draw a lens projection plane diagram according to the required parameters of the finished product of the special-shaped lens;

[0033] S02, fitting a virtual complete circle corresponding to the concave curvature surface and the convex curvature surface on the projection plane according to the concave curvature surface and the convex curvature surface to be processed on the lens; Figure 3 As shown, after projection, the center position of the lens and the center of each curvature surface can be determined.

[0034] S03, confirming the relative position coordinates of the center of the virtual complete circle on the lens and calibrating it;

[0035] S04, determining the coordinates of the points on the arcs of the corresponding concave curvature surface and convex curvature surface that are farthest from the grinding wheel axis according to the relative position coordinates;

[0036] S05. Determine the thickness value of the lens corresponding to the corresponding position according to the coordinate value.

[0037] The process of determining the mean diameter of the grinding wheel according to the thickness value of the present invention comprises: setting the curvature of the edge of the lens along the thickness direction when the grinding wheel processes the lens , according to the curvature And the thickness value h is used to calculate the grinding wheel median diameter r, , curvature It is usually taken to be less than 0.1 to ensure that the edge thickness of the lens meets the requirements and will not be concave due to cutting of the grinding wheel edge.

[0038] For the continuous convex and concave curvature surfaces on the edge of special-shaped lenses, the curvature of the grinding wheel surface is designed according to the curvature of the corresponding curvature surface, with the calculated center diameter of the grinding wheel as the center. The grinding wheels corresponding to adjacent curvature surfaces are connected end to end as a whole. During processing, all continuous curvature surfaces are processed synchronously, and synchronous processing is achieved using one grinding wheel, thereby ensuring the consistency of the processing accuracy of each curvature surface and avoiding deviation.

[0039] In order to improve the determination efficiency when confirming multiple grinding wheels at the same time and enable the grinding wheels to be changed and adjusted synchronously, when confirming the middle diameters of multiple grinding wheels, a basic grinding wheel model is first established according to the number of grinding wheels and the corresponding curvature surface sizes, and the middle diameter size corresponding to the smallest diameter grinding wheel is first determined. Then, the calculated middle diameter value of the grinding wheel is enlarged according to the relative position relationship of the curvature surface corresponding to the smallest diameter grinding wheel on the projection plane, and the middle diameter value of the processing grinding wheel required for each curvature surface of the lens is obtained.

[0040] For the case of uniform lens thickness, the grinding wheel mean diameter value obtained by the above process can meet the required processing requirements. However, for the case of curvature on the lens surface, the lens thickness at different processing positions is different, and the curvature caused by the corresponding grinding wheel processing will also change. Therefore, it is necessary to check whether the obtained grinding wheel mean diameter value meets the requirements to ensure that even at the position with the largest thickness, the curvature caused by the processing also meets the requirements. The following scheme is specifically adopted: after obtaining the mean diameter values ​​of all grinding wheels, a lens model is established according to the surface curvature of the special-shaped lens, and the curvature caused by the mean diameter of the grinding wheel at the position with the largest processing thickness on the lens is calculated, and the mean diameter value of the grinding wheel at this position is corrected according to the calculation result; the mean diameter values ​​of the grinding wheel at other positions are adjusted synchronously; the model can be established using CAD. After the curvature and other parameters are determined, the diameter of a certain grinding wheel is adjusted, and the other dimensions will change synchronously, thereby achieving the purpose of quickly obtaining the final grinding wheel size.

[0041] The present invention also discloses a special-shaped lens processing device, using the above processing method, such as Figure 1As shown, it includes a clamping fixture 2 for clamping the lens 1 and a grinding machine for cutting the curvature surface of the edge of the lens 1 , wherein the grinding wheel 3 of the grinding machine has a processing curvature surface matching the curvature surface of the lens 1 .

[0042] Specifically, the clamping jig 2 of the present invention is a T-shaped structure, made of stainless steel, and has a groove 4 at the end with a larger diameter for accommodating the lens 1. After the lens 1 is inserted into the groove 4, beeswax is set between the gap between the lens 1 and the groove 4 for fixing. After the lens 1 is fixed on the clamping jig 2, the line connecting the centers of the edges of the curvature surfaces of the processed side lenses is parallel to the axis of the grinding wheel 3, and the cutting position of the lens 1 is located outside the groove 4.

[0043] The processing of the lens of the present invention is described below with reference to a specific embodiment.

[0044] like Figure 2 As shown, the special-shaped lens of the present invention includes two concave arcs with a curvature of 9.04±1, three concave arcs with a curvature of 2.3±2, and the curvature surfaces are recorded from right to left as shown in the figure: the first convex curvature surface 2.1.1, the first concave curvature surface 2.1.2, the second convex curvature surface 2.1.3, the second concave curvature surface 2.1.4, and the third convex curvature surface 2.1.5. There is no requirement for the wall thickness curvature of the three transitional convex arcs.

[0045] The first convex curvature surface 2.1.1 and the third convex curvature surface 2.1.5 are symmetrical about the center of the lens, and the first concave curvature surface 2.12 and the second concave curvature surface 2.1.4 are symmetrical about the center of the lens; therefore, it is only necessary to calculate the grinding wheel mean diameter corresponding to one of the concave curvature surfaces; for asymmetric situations, the grinding wheel mean diameter value with the smallest required processing diameter can be calculated according to the scheme of the present invention, and the other grinding wheel mean diameter can be increased according to the relative position of the curvature surface projection, and then verified according to the thickness value.

[0046] The lens material of the present invention is K9, the diameter is 50, and the curvatures of the upper and lower surfaces of the lens are 91.99 and 288.42 respectively.

[0047] Projection plan Figure 3 As shown, the corresponding curvature center position can be determined according to the curvature of the arc. In the embodiment of the present invention, the curvature centers of each curvature surface are on the same straight line. During processing, the grinding wheel axis is parallel to the straight line.

[0048] According to the lens size and the center of curvature of the present invention, the thickness value corresponding to the point farthest from the grinding wheel axis during processing can be determined, such as Figure 3 As shown, according to the corresponding relationship between lens thickness and plane projection, Figure 32.1.6 is the thickness value corresponding to the farthest edge of the second concave curvature surface 2.1.4, and 2.1.7 is the thickness value corresponding to the farthest edge of the first concave curvature surface 2.1.2.

[0049] According to the lens size and curvature specifications of the present invention, it can be concluded that both 2.1.6 and 2.1.7 are 6.92 mm. When r=55 mm, the curvature is , so the corresponding grinding wheel diameter is 110mm, and according to the curvature, the following is obtained: Figure 4 The shape of the grinding wheel shown, Figure 4 3.11 is the grinding wheel middle diameter required for machining the third convex curvature surface 2.1.5, 3.6 is the intersection of the grinding wheel middle diameter and the grinding wheel axis, 3.12 is the grinding wheel middle diameter required for machining the second concave curvature surface 2.1.4, 3.7 is the intersection of the corresponding grinding wheel middle diameter and the grinding wheel axis, 3.13 is the grinding wheel middle diameter required for machining the second convex curvature surface 2.1.3, 3.8 is the intersection of the corresponding grinding wheel middle diameter and the grinding wheel axis, 3.14 is the grinding wheel middle diameter required for machining the first concave curvature surface 2.1.2 The grinding wheel middle diameter is 3.9, which is the intersection of the corresponding grinding wheel middle diameter and the grinding wheel axis. 3.15 is the grinding wheel middle diameter required for machining the first convex curvature surface 2.1.1. 3.10 is the intersection of the corresponding grinding wheel middle diameter and the grinding wheel axis. When the grinding wheel axis, the grinding wheel middle diameters of each part and the curvature are determined, the required grinding wheel can be machined, and then the machined grinding wheel can be used for batch cutting of lenses, and the consistency of machining accuracy of each curvature surface of the lens is ensured, which is convenient for subsequent assembly of the lens.

Claims

1. A method for processing a special-shaped lens, wherein the edge of the special-shaped lens is provided with a circular arc-shaped concave curvature surface and a convex curvature surface, characterized in that: The grinding wheel curvature required for processing is determined according to the curvature of the concave curvature surface and the convex curvature surface of the special-shaped lens, and the median diameter of the grinding wheel is determined according to the thickness value of the lens processing area at the farthest position from the grinding wheel center axis. The grinding wheel shape is confirmed according to the median diameter value of the grinding wheel and the curvature value of the corresponding processed curvature surface. The determined grinding wheel is used to perform cutting processing on the edge of the special-shaped lens. For the continuous edge contour of the lens, the grinding wheel adopts an integrated structure that matches the continuous length of the profile line, and the concave curvature surface and the convex curvature surface are processed simultaneously. The process of determining the thickness of the lens processing area at the position farthest from the center axis of the grinding wheel includes the following steps: S01. Draw a lens projection plane diagram according to the required parameters of the finished product of the special-shaped lens; S02, fitting a virtual complete circle corresponding to the contours of the concave curvature surface and the convex curvature surface on the projection plane according to the concave curvature surface and the convex curvature surface to be processed on the lens; S03, confirming the relative position coordinates of the center of the virtual complete circle on the lens and calibrating it; S04, determining the coordinates of the points on the arcs of the corresponding concave curvature surface and convex curvature surface that are farthest from the grinding wheel axis according to the relative position coordinates; S05, determining the thickness value of the lens corresponding to the corresponding position according to the coordinate value; The process of determining the mean diameter of the grinding wheel according to the thickness value includes: setting the curvature of the edge of the lens along the thickness direction when the grinding wheel processes the lens , according to the curvature And the thickness value h is used to calculate the grinding wheel median diameter r, ; For the continuous convex and concave curvature surfaces on the edge of special-shaped lenses, the grinding wheel surface curvature is designed according to the curvature of the corresponding curvature surface with the calculated center diameter of the grinding wheel as the center. The grinding wheels corresponding to adjacent curvature surfaces are connected end to end as a whole. During processing, the processing of all continuous curvature surfaces is completed synchronously.

2. A method for processing special-shaped lenses according to claim 1, characterized in that: When confirming the mean diameters of multiple grinding wheels, first establish a basic grinding wheel model based on the number of grinding wheels and the corresponding curvature surface sizes, and first determine the mean diameter size corresponding to the smallest diameter grinding wheel. Then, based on the relative position relationship of the curvature surface corresponding to the smallest diameter grinding wheel on the projection plane, the calculated mean diameter value of the grinding wheel is enlarged for the remaining grinding wheels to obtain the mean diameter value of the processing grinding wheel required for each curvature surface of the lens.

3. The method for processing a special-shaped lens according to claim 1, characterized in that: After obtaining the mean diameter values ​​of all grinding wheels, a lens model is established according to the surface curvature of the special-shaped lens, the curvature caused by the mean diameter of the grinding wheel at the position with the maximum processing thickness on the lens is calculated, and the mean diameter value of the grinding wheel at this position is corrected according to the calculation result; the mean diameter values ​​of the grinding wheel at other positions are adjusted synchronously.

4. A device for processing special-shaped lenses, using the processing method according to any one of claims 1 to 3, characterized in that: It comprises a clamping fixture (2) for clamping a lens (1), and a grinding machine for cutting and processing the curvature surface of the edge of the lens (1), wherein the grinding wheel (3) of the grinding machine has a processed curvature surface matching the curvature surface of the lens (1).

5. The device for processing special-shaped lenses according to claim 4, characterized in that: The clamping fixture (2) is of a T-shaped structure, and a groove (4) for accommodating the lens (1) is provided at the end with a larger diameter. After the lens (1) is inserted into the groove (4), beeswax is provided between the gap between the lens (1) and the groove (4) for fixing.

6. The device for processing special-shaped lenses according to claim 5, characterized in that: The clamping fixture (2) is made of stainless steel.

7. The device for processing special-shaped lenses according to claim 4, characterized in that: After the lens (1) is fixed on the clamping fixture (2), a line connecting the centers of the edges of the curvature surfaces of the lens on the processing side is parallel to the axis of the grinding wheel (3), and the cutting position of the lens (1) is located outside the groove (4).

Images