A high-precision aperture processing control method and processing device for concave lens

Abstract

The present invention discloses a high-precision aperture processing control method and processing device for concave lenses. The method measures incoming lens data, determines the corresponding sagitta deviation by the deviation between the concave surface curvature of the incoming lens and the standard curvature, and calculates the corresponding sagitta by the target aperture size of the lens. Based on the sagitta and the center thickness of the lens, the grinding amount of the lens step surface is confirmed. By controlling the sagitta, the processing of different lens apertures is achieved. A simple and reliable high-precision thickness measurement device and method are used to accurately and quickly complete the high-precision processing and measurement of the aperture of the finished lens.

Description

Technical Field

[0001] The present invention relates to the technical field of concave lens processing, and in particular to a high-precision aperture processing control method and a processing device for a concave lens. Background Art

[0002] In lens assembly systems, there are usually different types of concave lenses to adapt to the optical system. Especially in laser system applications, the concave aperture of the optical element needs to match the size of the laser beam to ensure effective light reception, transmission and focusing. Mismatched apertures can lead to a decrease in beam quality. At the same time, the aperture size of the lens also determines the shape accuracy of the lens itself. The adaptation accuracy with other structures plays a very important role in the entire device, especially in high-frequency vibration and high and low temperature extremes. In order to ensure the stability of the optical transmission system in the entire device system, the lens structure accuracy affected by the concave aperture of the lens is crucial to the stability of the entire device system.

[0003] Currently, the aperture size of concave lenses is primarily achieved by controlling the raw material size and the curvature of the ground concave surface. However, this curvature can deviate from the standard curvature of the lens design, resulting in inconsistent apertures across the finished lenses. This inability to fully meet lens aperture precision requirements impacts the performance of the equipment in which the lenses are manufactured. Furthermore, existing lens aperture measurements using projectors have a large measurement error, typically around 0.05mm. Using higher-precision measuring equipment is prohibitively expensive, making it unsuitable for mass production. Summary of the Invention

[0004] Technical purpose: In view of the shortcomings of the existing concave lens aperture processing precision control, the present invention discloses a high-precision aperture processing control method and processing device for concave lenses, which can avoid the lens aperture size being affected by curvature processing deviation, realize high-precision aperture processing and are easy to measure and control.

[0005] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0006] A high-precision aperture processing control method for a concave lens comprises the following steps:

[0007] S01. Measure the concave curvature, center thickness, and total height of the incoming lens to obtain the incoming lens data;

[0008] S02. Determine the curvature deviation based on the measured concave surface curvature and the standard curvature of the incoming lens processing, and confirm the sagittal deviation caused by the curvature deviation. The sagittal is the vertical distance between the center of the concave surface of the lens and the step surface of the lens;

[0009] S03, then calculating the sagittal height corresponding to the target aperture size based on the target aperture size of the incoming lens and the measured concave curvature, wherein the target aperture size is the designed aperture of the lens processing;

[0010] S04. Determine the final total lens height based on the sagittal height corresponding to the target aperture size, the sagittal height deviation caused by the curvature deviation, and the target center thickness of the incoming lens, and grind the incoming lens based on the obtained total lens height and the measured total height and center thickness of the incoming lens; the target center thickness is the designed center thickness of the lens processing.

[0011] Preferably, in step S02 of the present invention, a fixed tube with a fixed diameter is used to concentrically locate the concave surface and the flat surface of the incoming lens, and the sagittal deviation caused by the curvature deviation of the incoming lens is calculated based on the diameter of the fixed tube. The diameter of the fixed tube is smaller than the target aperture size of the lens; the diameter of the fixed tube is recorded as The curvature radius of the concave curvature of the incoming lens is R1, the curvature radius of the standard curvature is R2, and the sag deviation ; Indicates the sagittal height corresponding to the curvature radius R2, Indicates the sagittal height corresponding to the curvature radius R1.

[0012] Preferably, in step S04, the arrow height corresponding to the target aperture size is , sag deviation The total height of the lens is obtained by superimposing it with the target center thickness d, and the amount of grinding on the step surface of the lens is determined based on the measured center thickness and total height of the incoming lens.

[0013] Preferably, the fixing tube of the present invention is a thin-walled tube, and the outer diameter of the fixing tube is used as the basis for calculating the sagittal deviation. The fixing tube is used as the positioning reference during lens grinding, and the position of the lens on the machine tool is positioned through the fixing tube.

[0014] Preferably, the process of positioning the lens by a fixed tube of the present invention includes confirming the distance between the step surface of the lens and the center of the concave surface of the lens based on the measured center thickness and total height of the incoming lens, and confirming the distance between the end of the fixed tube and the step surface of the lens by measuring the concave surface curvature of the incoming lens and the diameter of the fixed tube, and finally positioning the position of the step surface of the incoming lens on the processing machine tool by the position of the fixed tube on the processing machine tool.

[0015] The present invention discloses a high-precision aperture processing device for concave lenses, which uses the above-mentioned processing control method and includes an edge grinder and a grinding wheel. A lens clamping mechanism is provided on the edge grinder and is arranged parallel to the main axis of the grinding wheel. When the lens is processed, the lens is clamped and fixed by the clamping mechanism, and the edge grinder drives the grinding wheel to rotate to grind the lens.

[0016] Preferably, the lens clamping mechanism of the present invention comprises two fixing tubes arranged opposite to each other, and the lens is clamped and fixed by the fixing tubes contacting the concave surface and the flat surface of the lens.

[0017] Preferably, the fixing tube of the two fixing tubes of the present invention that matches the concave surface of the lens serves as a positioning tube and remains relatively fixed to the edge grinding machine, and the position of the processed step surface of the lens is positioned by the positioning tube.

[0018] Beneficial effects: The high-precision aperture processing control method and processing device of a concave lens disclosed in the present invention have the following beneficial effects:

[0019] 1. The present invention measures the incoming lens data, determines the corresponding sagitta deviation by the deviation between the concave curvature of the incoming lens and the standard curvature, and calculates the corresponding sagitta by the target aperture size of the lens. Based on the sagitta and the center thickness of the lens, the grinding amount of the lens step surface is confirmed. By controlling the sagitta, the processing of different lens apertures can be achieved. The simple and reliable high-precision thickness measurement device and method can accurately and quickly complete the high-precision processing and measurement of the aperture of the finished lens.

[0020] 2. The present invention's lens aperture control method can, on the one hand, achieve high-precision aperture processing for a single concave lens. Furthermore, because the curvature of the concave surface processed by the lens processing machine is essentially the same for the same type of lens, or the fluctuation range is very small, the concave lens inspection results and edging requirements can be used to provide guidance for adjusting the machine processing parameters, thereby achieving high-precision control of the lens aperture directly from the original processing stage. This avoids the need for secondary aperture measurement using high-precision measuring equipment, reduces costs, and improves production efficiency.

[0021] 3. The present invention positions the concave surface of the lens through a fixed tube with a fixed diameter. Based on parameters such as the curvature of the concave surface of the lens and the diameter of the fixed tube, the position of the step surface of the lens on the machine tool can be accurately obtained, which facilitates the subsequent control of the machine tool to perform grinding processing on the step surface of the lens without being affected by measurement accuracy, thereby improving positioning efficiency and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments or the prior art.

[0023] Figure 1 This is a structural diagram of a concave lens of the present invention;

[0024] Figure 2 This is a schematic diagram of a concave lens of the present invention being fixed on an edge grinding machine;

[0025] Figure 3This is a schematic diagram of the grinding wheel structure of the edge grinding machine of the present invention;

[0026] Among them, 1-grinding wheel, 2-fixed tube, 3-lens, 4-spindle, 5-nut. DETAILED DESCRIPTION

[0027] Reference will now be made in detail to the embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by way of explanation of the apparatus, composition, and materials of the present disclosure, and is not intended to be limiting. On the contrary, the following description provides a convenient illustration of exemplary embodiments for implementing the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made within the teachings of the present disclosure without departing from the scope or spirit of the present disclosure.

[0028] like Figure 1 As shown, this is the concave lens to be processed by the present invention. According to the orientation shown in the figure, the left side of the lens is a concave surface, the flat area outside the concave surface is the lens step surface, and the lens aperture is the diameter of the concave edge; the right side of the lens is a flat surface.

[0029] The present invention provides a high-precision aperture processing control method for a concave lens, which does not require the use of high-precision measuring equipment to measure the concave surface aperture of the lens, while achieving precise control of the concave surface aperture.

[0030] The specific method includes the following steps:

[0031] S01. Measure the concave curvature, center thickness, and total height of the incoming lens to obtain the incoming lens data;

[0032] The curvature of a concave surface is represented by the corresponding radius of curvature, such as Figure 1 As shown in the figure, R1 represents the curvature radius corresponding to the concave curvature of the concave lens after actual processing, and R2 represents the curvature radius corresponding to the standard curvature of the concave surface of the lens when designing the lens. The actual back curvature after processing will fluctuate around the standard curvature due to the setting of the processing equipment or processing parameters, and accordingly R1 will also be smaller or larger than R2.

[0033] S02. Determine the curvature deviation based on the measured concave surface curvature and the standard curvature of the incoming lens processing, and confirm the sagittal deviation caused by the curvature deviation. The sagittal is the vertical distance between the center of the concave surface of the lens and the step surface of the lens;

[0034] When confirming the sag deviation, a fixed tube with a fixed diameter is used to concentrically locate the concave and flat surfaces of the incoming lens. The sag deviation caused by the curvature deviation of the incoming lens is calculated based on the diameter of the fixed tube. The diameter of the fixed tube is smaller than the target aperture size of the lens; the diameter of the fixed tube is recorded as The curvature radius of the concave curvature of the incoming lens is R1, the curvature radius of the standard curvature is R2, and the sag deviation ; Indicates the sagittal height corresponding to the curvature radius R2, Indicates the sagittal height corresponding to the curvature radius R1.

[0035] The calculation of the corresponding sagitta is based on the relationship between the sagitta and the radius of curvature: , R represents the radius of curvature, Indicates the corresponding aperture size. In the embodiment of the present invention, when calculating the sag deviation, The corresponding value is the diameter of the fixed pipe .

[0036] S03, then calculating the sagittal height corresponding to the target aperture size based on the target aperture size of the incoming lens and the measured concave curvature, wherein the target aperture size is the designed aperture of the lens processing;

[0037] The target aperture size of the lens is recorded as , The value is , the corresponding target aperture size corresponds to the arrow height .

[0038] S04. Determine the final total lens height based on the sagittal height corresponding to the target aperture size, the sagittal height deviation caused by the curvature deviation, and the target center thickness of the incoming lens, and grind the incoming lens based on the obtained total lens height and the measured total height and center thickness of the incoming lens; the target center thickness is the designed center thickness of the lens processing.

[0039] By calculating the target aperture size corresponding to the arrow height , sag deviation The total height H of the lens is obtained by superimposing it with the target center thickness d, and the amount of grinding on the step surface of the lens is determined based on the measured center thickness d1 and total height H1 of the incoming lens.

[0040] After measuring the total height H1 and the center thickness d1, the distance from the center of the corresponding lens concave surface to the current lens step surface is H1-d1; the grinding amount on the side where the lens step surface is located is H1-d1- ; The plane on the right side of the lens can be controlled according to the total height.

[0041] The fixing tube of the present invention is preferably a thin-walled tube to avoid affecting the positioning accuracy of the step surface of the lens. The material is a copper tube. The outer diameter of the fixing tube is used as the basis for calculating the sagittal deviation, and the fixing tube is used as the positioning reference during the lens grinding process. The position of the lens on the machine tool is positioned through the fixing tube.

[0042] The process of positioning the lens by a fixed tube of the present invention includes confirming the distance between the step surface of the lens and the center of the concave surface of the lens based on the measured center thickness and total height of the incoming lens, and confirming the distance between the end of the fixed tube and the step surface of the lens by measuring the curvature of the concave surface of the incoming lens and the diameter of the fixed tube. Finally, the position of the step surface of the incoming lens on the processing machine tool is positioned by the position of the fixed tube on the processing machine tool. After obtaining the accurate position of the step surface of the lens on the machine tool, the machine tool can be used to perform grinding processing according to the calculated grinding amount.

[0043] like Figure 2 and Figure 3 As shown, the present invention also discloses a high-precision aperture processing device for concave lenses, using the above-mentioned processing control method, including an edge grinder and a grinding wheel 1, a lens clamping mechanism arranged parallel to the main shaft 4 where the grinding wheel 1 is located is set on the edge grinder, the grinding wheel 1 has a through hole in the center, and the end face is a groove-shaped. The groove and the adjacent side wall surface are loaded with a layer of diamond, and are connected to the main shaft 4 through the through hole. The main shaft 4 is a threaded shaft, and the grinding wheel 1 is locked and fixed on the main shaft 4 by a nut 5; when the lens 3 is processed, the lens 3 is clamped and fixed by the clamping mechanism, and the edge grinder drives the grinding wheel 1 to rotate to grind the lens.

[0044] The lens clamping mechanism of the present invention includes two fixed tubes 2 arranged opposite to each other, and the lens is clamped and fixed by the fixed tubes 2 contacting the concave surface and flat surface of the lens 3; the fixed tube 2 of the two fixed tubes 2 that cooperates with the concave surface of the lens serves as a positioning tube to remain relatively fixed with the edge grinder, and the position of the processed step surface of the lens is positioned by the positioning tube. The fixed tube 2 is a cylindrical copper tube, and the end close to the lens is a hollow columnar structure. When positioning the lens, the hollow end is used to position the lens.

[0045] A specific embodiment is provided below to illustrate the aperture processing control method of the present invention.

[0046] Assuming the parameters of the finished lens, the material is K9, R1=32.42, R2=27.93, the center thickness is d=6.86, the lens diameter Φ=50, the target aperture size =44, where the fixed pipe diameter is =40, the above data units are unified in mm.

[0047] First, calculate the sag deviation by fixing the tube diameter and the curvature radii R1 and R2. In the embodiment of the present invention, R2 is smaller than R1, and the corresponding , .

[0048] The sag corresponding to the target aperture size of the lens =8.6mm.

[0049] The total height required for lens processing is H=6.86+1.53+8.6=16.99mm.

[0050] Based on the measured total height H1 and center thickness d1, the grinding amount on the side where the step surface of the lens is located is H1-d1-8.6; if the total height of the lens needs to be controlled, the grinding amount on the side where the flat surface of the lens is located is d1-d-1.53. In addition, since the allowable error for the total height of the lens is relatively large during lens processing, the deviation of the total height can be ignored when the lens has been processed on the machine tool according to the preset parameters. In situations where higher dimensional accuracy of the lens is required, the grinding amount provided by the present invention can be used to grind the flat surface of the lens.

[0051] After confirming the grinding amount, the lens is installed on the edger and clamped by the lens clamping mechanism to ensure that the lens center deviation requirements are met. After the lens is fixed, the coordinate position of the lens step surface on the edger is positioned according to the lens measurement parameters and the position of the end of the fixed tube. Then, the grinding wheel is controlled to grind the lens end face according to the set grinding amount until the sagittal height of the lens step surface reaches the predetermined requirement. At this time, the concave diameter of the lens is the target diameter size of the lens, and the lens processing is completed.

[0052] The processing method of the present invention can achieve precise processing and control of the aperture of the concave lens, and can also provide guidance for the processing parameters of the machine tool during batch processing, thereby improving the processing efficiency and the processing accuracy of the lens.

Claims

1. A high-precision aperture processing control method for a concave lens, characterized in that: Including steps: S01. Measure the concave curvature, center thickness, and total height of the incoming lens to obtain the incoming lens data; S02. Determine the curvature deviation based on the measured concave surface curvature and the standard curvature of the incoming lens processing, and confirm the sagittal deviation caused by the curvature deviation. The sagittal is the vertical distance between the center of the concave surface of the lens and the step surface of the lens; S03, then calculating the sagittal height corresponding to the target aperture size based on the target aperture size of the incoming lens and the measured concave curvature, wherein the target aperture size is the designed aperture of the lens processing; S04. Determine the final total lens height based on the sagittal height corresponding to the target aperture size, the sagittal height deviation caused by the curvature deviation, and the target center thickness of the incoming lens, and grind the incoming lens based on the determined total lens height and the measured total height and center thickness of the incoming lens; the target center thickness is the designed center thickness of the lens; In step S02, a fixed tube with a fixed diameter is used to concentrically locate the concave surface and the flat surface of the incoming lens. The sagittal deviation caused by the curvature deviation of the incoming lens is calculated based on the diameter of the fixed tube. The diameter of the fixed tube is smaller than the target aperture size of the lens; the diameter of the fixed tube is recorded as The curvature radius of the concave curvature of the incoming lens is R1, the curvature radius of the standard curvature is R2, and the sag deviation ; Indicates the sagittal height corresponding to the curvature radius R2, Indicates the sagittal height corresponding to the curvature radius R1; The fixed tube is a thin-walled tube. The outer diameter of the fixed tube is used as the basis for calculating the sagittal deviation. The fixed tube is also used as the positioning reference during lens grinding. The position of the lens on the machine tool is positioned through the fixed tube.

2. The high-precision aperture processing control method of a concave lens according to claim 1, characterized in that: In step S04, the target aperture size corresponding to the height, height deviation The total height of the lens is obtained by superimposing the measured center thickness and the target center thickness, and the amount of grinding on the step surface of the lens is determined based on the measured center thickness and total height of the incoming lens.

3. The high-precision aperture processing control method for a concave lens according to claim 1, characterized in that: The process of positioning the lens through a fixed tube includes confirming the distance between the lens step surface and the center of the lens concave surface based on the measured center thickness and total height of the incoming lens, and confirming the distance between the end of the fixed tube and the lens step surface by measuring the concave surface curvature of the incoming lens and the diameter of the fixed tube. Finally, the position of the lens step surface of the incoming lens on the processing machine tool is positioned by the position of the fixed tube on the processing machine tool.

4. A high-precision aperture processing device for a concave lens, using the processing control method according to any one of claims 1 to 3, characterized in that: The invention comprises an edge grinder and a grinding wheel (1). A lens clamping mechanism is provided on the edge grinder and is parallel to a main shaft (4) on which the grinding wheel (1) is located. When processing a lens (3), the lens (3) is clamped and fixed by the clamping mechanism, and the edge grinder drives the grinding wheel (1) to rotate to grind the lens.

5. The high-precision aperture processing device for a concave lens according to claim 4, characterized in that: The lens clamping mechanism comprises two fixing tubes (2) arranged opposite to each other, and the lens is clamped and fixed by contact between the fixing tubes (2) and the concave surface and the flat surface of the lens (3).

6. The high-precision aperture processing device for a concave lens according to claim 5, characterized in that: Of the two fixing tubes (2), the fixing tube that matches the concave surface of the lens serves as a positioning tube and is kept relatively fixed with the edge grinding machine, and the position of the processed step surface of the lens is positioned by the positioning tube.

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