Glass micro-matrix molding and compensation processing method based on air pressure dynamic balance

Abstract

The application discloses a glass micro-matrix mold forming and compensation processing method based on air pressure dynamic balance, and belongs to the field of precise optical element manufacturing, and comprises the following steps: S1, forming a mold cavity structure suitable for a glass micro-matrix by processing a mold unit cell according to a preset process; S2, establishing a gas expansion pressure balance model, designing pressure cycle parameters, adding a glass blank into the mold cavity, performing a pressurization and pressure release cycle based on the parameters calculated by the gas expansion pressure balance model and the pressure cycle parameters, controlling glass shrinkage / expansion auxiliary exhaust by using a temperature gradient, and filling the mold cavity with the glass until the glass is completely filled in the mold cavity; and S3, constructing an air pressure-deformation coupling compensation model, calculating a compensation amount of each unit cell, converting the compensation amount into a grinding head feeding amount, and finally completing the processing of the glass micro-matrix element according to the grinding head feeding amount. The mold processing, dynamic mold pressing and compensation correction steps can be adapted to existing precise forming equipment, a production line does not need to be massively transformed, and industrialization cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of precision optical component manufacturing, and in particular to a glass micro-matrix molding and compensation processing method based on dynamic air pressure balance. Background Technology

[0002] Glass micro-matrix elements, due to their advantages such as high integration and high optical performance, are widely used in imaging, sensing, and optical communication. Current micro-matrix lens molding technology mainly relies on traditional hot-pressing processes, but it suffers from the following key drawbacks: 1. When forming a micron-level matrix structure, the initial gas in the mold cavity and the gas released during the glass heating process are difficult to completely expel, which causes the glass melt to be unable to fully fill the fine structure of the mold cavity, resulting in defects such as missing corners and voids; 2. Residual gas is compressed in the mold cavity to form a high-pressure zone. The pressure is unbalanced with the external pressure, causing the profile of the molded element to deviate from the design value and making it difficult to control the accuracy (e.g., the profile deviation of PV often exceeds 6μm). 3. Post-compensation processing often adopts a "surface shape-lens" corresponding compensation strategy, which only corrects the deviation between the measured contour and the design contour, without considering the influence of the air pressure balance relationship on the component deformation during molding. After compensation, the surface roughness (Ra) of the component is still higher than 0.1μm, and the array consistency (3σ) only reaches ±2.1μm, which cannot meet the requirements of high-precision optical applications.

[0003] Therefore, there is an urgent need for a technical solution that can address issues such as incomplete gas discharge, pressure imbalance affecting accuracy, and failure to consider pressure balance, in order to improve the molding quality and consistency of glass micro-matrix components. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies, such as incomplete gas discharge, pressure imbalance affecting accuracy, and failure to consider pressure balance. It provides a glass micro-matrix molding and compensation processing method based on dynamic pressure balance.

[0005] To address the aforementioned technical problems, the present invention provides the following technical solution: A glass micro-matrix molding and compensation processing method based on dynamic air pressure balance includes the following steps: S1: Process the mold cells according to the preset process to form a mold cavity structure that adapts to the glass micro matrix; S2: Establish a gas expansion pressure balance model and design pressure cycle parameters. Add the glass preform into the mold cavity. Execute a pressurization-depressurization cycle based on the parameters calculated by the gas expansion pressure balance model and the pressure cycle parameters. Use the temperature gradient to control the glass shrinkage / expansion to assist in venting until the glass completely fills the mold cavity. S3: Construct a pressure-deformation coupling compensation model and calculate the compensation amount for each cell. Convert the compensation amount into the grinding head feed amount and finally complete the processing of the glass micro-matrix element based on the grinding head feed amount.

[0006] As a preferred embodiment of the present invention, the mold cavity structure in step S1 includes: opening a predetermined number and radius of microholes on the side wall of the mold cavity, wherein the microholes are exhaust channels.

[0007] As a preferred embodiment of the present invention, step S2, which involves establishing a gas expansion pressure balance model, includes: S21: Let the initial gas volume in the mold cavity be V0 (mm³); the temperature be T (mm³); and the number of gas moles be n. According to the modified van der Waals equation: Where 'a' is the correction factor for the intermolecular attraction of gas molecules, in Pa·m 6 / mol²; b is the gas molecule volume correction factor, unit: m³ / mol; R is the gas constant, 8.314 J / (mol·K); V represents gas pressure, in Pa; V represents gas volume, in m³. S22: Through periodic pressure changes This makes the glass fill volume With gas volume Satisfy the following formula: in, The rate of change of glass filling volume is expressed in m³ / s; k is the glass viscosity coefficient, expressed in m³ / (s·Pa). External pressure, unit: Pa; This is the gas pressure, unit: Pa.

[0008] As a preferred embodiment of the present invention, the design pressure cycle parameters in step S2 include: the flow rate Q of the gas discharged through pressure relief follows Poiseuille's law, as shown in the formula: in, The radius of the micropore is in meters (m). Gas viscosity, unit: Pa·s; The length of the channel is in meters (m). Number of holes; This represents the change in air pressure. Decompression time Must meet: in, Atmospheric pressure, unit: Pa; Based on gas residue threshold Number of loops satisfy: in, V represents the volume of gas discharged in a single cycle, in mm³, and V0 represents the initial gas volume in the mold cavity.

[0009] As a preferred embodiment of the present invention, the pressure-deformation coupling compensation model described in step S3 is as follows: in, The height of the profile after compensation, in μm; The measured profile height of the workpiece, in μm; This is CAD model data, unit: μm; This represents the air pressure difference during the molding process, in kPa. (This is the pressure deformation coefficient, unit: μm / (kPa·μm-1)); The curvature of the mold profile is expressed in μm-1.

[0010] As a preferred embodiment of the present invention, the calculation of the compensation amount of each cell in step S3 includes: measuring the actual workpiece contour height of a single cell and the corresponding CAD model data, calculating the spatial error between the measured data and the design data, eliminating the coordinate system error caused by clamping and measurement position offset, and achieving spatial alignment; Calculate the profile deviation at each coordinate point: in, This is CAD model data, unit: μm; The measured contour height of the workpiece is in μm; the corresponding parameters are imported into the air pressure-deformation coupling compensation equation to calculate the replenishment amount for each cell.

[0011] As a preferred embodiment of the present invention, step S3, which involves converting the compensation amount into the grinding head feed amount, includes: converting the compensation amount into grinding depth data in the grinding machine coordinate system, i.e., the grinding head feed amount; and generating a machining path based on the grinding depth data.

[0012] As a preferred embodiment of the present invention, the specific calculation formula for converting the compensation amount into the grinding head feed amount is as follows: in, This refers to the feed rate of the grinding head, in μm. The included angle of the grinding edge, with a value range of 55°-75°; The springback coefficient of the material is taken as 0.02-0.05 for tungsten steel; The grinding temperature is controlled below 150℃.

[0013] As a preferred embodiment of the present invention, step S3 further includes online real-time correction of the grinding head feed rate, wherein the correction formula is: in, This is the final grinding feed rate, in μm. This is the pressure gain coefficient, with a value ranging from 0.1 to 0.3. The standard operating pressure is a set value. This represents the change in air pressure.

[0014] Compared with the prior art, the advantages of the present invention are as follows: By using periodic pressure fluctuations and pressurization / depressurization cycles, combined with gradient temperature control, the gas in the mold cavity is gradually discharged, improving the glass filling integrity to over 99%. Dynamic pressure balance eliminates high-pressure areas of residual gas, and with pressure-deformation coupling compensation, the PV profile deviation of the molded element is reduced from 6.2μm to 0.9μm, and the surface roughness Ra is reduced from 0.1μm to 0.02μm. Online compensation correction takes into account real-time pressure fluctuations, optimizing the array consistency (3σ) from ±2.1μm to ±0.6μm, meeting the mass production requirements of high-precision optical elements. Each step of mold processing, dynamic molding, and compensation correction can be adapted to existing precision molding equipment, without the need for large-scale production line modifications, thus reducing industrialization costs. Attached Figure Description

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings: Figure 1 This is a flowchart of a glass micro-matrix molding and compensation processing method based on dynamic air pressure balance as described in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the progressive gas discharge in a glass micro-matrix molding and compensation processing method based on dynamic gas pressure balance as described in Embodiment 1 of the present invention. Figure 3 This is a compensation correction diagram of a glass micro-matrix molding and compensation processing method based on dynamic air pressure balance as described in Embodiment 1 of the present invention; Figure 4This is a schematic diagram comparing the filling rate of a glass micro-matrix molding and compensation processing method based on dynamic air pressure balance as described in Embodiment 1 of the present invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance, or suggesting any such actual relationship or order between these entities or operations. Additionally, the terms "connected," "linked," etc., can refer to a direct connection between components or an indirect connection via other components.

[0018] Example 1 A glass micro-matrix molding and compensation processing method based on dynamic air pressure balance, such as... Figure 1 As shown, it includes the following steps: S1: Process the mold cells according to the preset process to form a mold cavity structure that adapts to the glass micro matrix; Preferably, the mold cavity structure described in step S1 includes: opening a predetermined number and radius of microholes on the side wall of the mold cavity, wherein the microholes are exhaust channels.

[0019] S2: Establish a gas expansion pressure balance model and design pressure cycle parameters. Add the glass preform into the mold cavity, and execute a pressurization-depressurization cycle based on the parameters calculated by the gas expansion pressure balance model and the pressure cycle parameters, such as... Figure 2 As shown, the temperature gradient is used to control the shrinkage / expansion of the glass to assist in venting until the glass completely fills the mold cavity; Preferably, the establishment of the gas expansion pressure balance model includes: S21: Let the initial gas volume in the mold cavity be V0 (mm³); the temperature be T (mm³); and the number of gas moles be n. According to the modified van der Waals equation: Where 'a' is the correction factor for the intermolecular attraction of gas molecules, in Pa·m 6 / mol²; b is the gas molecule volume correction factor, unit: m³ / mol; R is the gas constant, 8.314 J / (mol·K); V represents gas pressure, in Pa; V represents gas volume, in m³. S22: Through periodic pressure changes This makes the glass fill volume With gas volume Satisfy the following formula: in, The rate of change of glass filling volume is expressed in m³ / s; k is the glass viscosity coefficient, expressed in m³ / (s·Pa). External pressure, unit: Pa; This is the gas pressure, unit: Pa.

[0020] Preferably, the design pressure cycle parameters mentioned in step S2 include: the flow rate Q of the gas discharged through pressure relief follows Poiseuille's law, as shown in the formula: in, The radius of the micropore is in meters (m). Gas viscosity, unit: Pa·s; The length of the channel is in meters (m). Number of holes; This represents the change in air pressure. Decompression time Must meet: ,in, Atmospheric pressure, unit: Pa; Based on gas residue threshold Number of loops satisfy: ,in, V represents the volume of gas discharged in a single cycle, in mm³, and V0 represents the initial gas volume in the mold cavity.

[0021] S3: Construct a pressure-deformation coupling compensation model and calculate the compensation amount for each cell. Convert the compensation amount into the grinding head feed amount and finally complete the processing of the glass micro-matrix element based on the grinding head feed amount. Preferably, the pressure-deformation coupling compensation model described in step S3 is: in, The height of the profile after compensation, in μm; The measured profile height of the workpiece, in μm; This is CAD model data, unit: μm; This represents the air pressure difference during the molding process, in kPa. (This is the pressure deformation coefficient, unit: μm / (kPa·μm-1)); The curvature of the mold profile is expressed in μm-1.

[0022] Preferably, the calculation of the compensation amount for each cell in step S3 includes: the calculation of the compensation amount for each cell in step S3 includes: measuring the actual workpiece contour height of a single cell and the corresponding CAD model data, calculating the spatial error between the measured data and the design data, eliminating the coordinate system error caused by clamping and measurement position offset, and achieving spatial alignment; Calculate the profile deviation at each coordinate point: in, This is CAD model data, unit: μm; The measured contour height of the workpiece is in μm; the corresponding parameters are imported into the air pressure-deformation coupling compensation equation to calculate the replenishment amount for each cell.

[0023] Preferably, step S3, which involves converting the compensation amount into the grinding head feed amount, includes: converting the compensation amount into grinding depth data in the grinding machine coordinate system, i.e., the grinding head feed amount; generating a machining path based on the grinding depth data to ensure that the grinding head can perform scanning machining according to the depth specified by the compensation model; and using the compensation value of each point in the air pressure-deformation coupling compensation model as the theoretical feed amount of the grinding head, taking into account the geometry of the grinding head and its material properties.

[0024] Furthermore, the specific calculation formula for converting the compensation amount into the grinding head feed amount is as follows: in, This refers to the feed rate of the grinding head, in μm. The included angle of the grinding edge, with a value range of 55°-75°; The springback coefficient of the material is taken as 0.02-0.05 for tungsten steel; The grinding temperature is controlled below 150℃.

[0025] Preferably, step S3 further includes online real-time correction of the grinding head feed rate, as shown in the correction compensation diagram below. Figure 3 As shown, the corrected formula is: in, This is the final grinding feed rate, in μm. This is the pressure gain coefficient, with a value ranging from 0.1 to 0.3. The standard operating pressure is a set value. This represents the change in air pressure.

[0026] Ultimately, the fill rate is, for example... Figure 4 As shown.

[0027] Example 2 This embodiment is a specific implementation of the glass micro-matrix molding and compensation processing method based on dynamic air pressure balance described in Embodiment 1; The parameters calculated based on the gas expansion pressure balance model specifically include: Initial volume of mold cavity =1mm 3 =1×10 -9 m³; initial temperature T = 525℃ ≈ 800K; initial atmospheric pressure = =10 5 pa; external pressure =5×10 5 pa; the gas is nitrogen, b = 3.87 × 10 -5 m³ / mol 1. Calculate the initial number of gas moles n: ≈1.5×10 -8 mol 2. Iterative simulation: Assume that at t=0, the gas volume V=V0 and the glass filling volume V g =0; For each time i; ①Based on the current gas volume V i Solve for the current gas pressure ; ② Calculate the pressure difference: - ; ③ Calculate the glass filling rate: ; ④ Calculate the volume of glass filling during this time period: ; ⑤ Update gas volume: ; ⑥ Update the total volume of the glass: + ; The gas pressure can be obtained through the above calculations. The glass filling rate rises rapidly to a stable value. It then gradually decreases, eventually approaching zero. ≈ The filling process stops. The final volume of gas compressed is the volume of the glass filling.

[0028] The design pressure cycle parameters include: Assume initial gas volume Micropore radius Number of holes ; 1. Single pressure relief flow rate ; 2. Decompression time S; 3. Number of loops =4 times.

[0029] Raw data: Measured profile deviation =4.8μm; Air pressure difference record curvature =0.35μm -1 ; Compensation calculation: =4.8-0.1×12×0.35=4.8-0.42=4.38μm Grinding execution: take =60°, , =120℃; Implement the correction: current , =0.2, ; The verification of the correction effect is shown in Table 1: Table 1. Verification Table of Correction Effect.

[0030] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0031] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A glass micro-matrix molding and compensation processing method based on air pressure dynamic balance, characterized in that, The method comprises the following steps: S1: processing the mold unit cell according to a preset process to form a mold cavity structure suitable for fitting a glass micro-matrix; S2: establishing a gas expansion pressure balance model, designing pressure cycle parameters, adding a glass blank into the mold cavity, performing a pressurization-depressurization cycle based on the parameters calculated by the gas expansion pressure balance model and the pressure cycle parameters, and controlling glass shrinkage / expansion assisted exhaust by using a temperature gradient until the glass completely fills the mold cavity; S3: constructing a gas pressure-deformation coupling compensation model and calculating the compensation amount of each unit cell, converting the compensation amount into a grinding head feed amount, and finally completing the processing of the glass micro-matrix element according to the grinding head feed amount.

2. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The mold cavity structure of step S1 comprises: a plurality of micro-holes with a preset number and radius are opened on the side wall of the mold cavity, and the micro-holes are exhaust channels.

3. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The establishment of the gas expansion pressure balance model of step S2 comprises: S21: set the initial gas volume in the mold cavity as V0, unit: mm³; temperature T, unit: mm³; and gas molar number n according to the corrected Van der Waals equation: wherein a is a correction coefficient of the attraction between gas molecules, unit: Pa-m 6 / mol2; b is a correction coefficient of the volume of gas molecules, unit: m3 / mol; R is a gas constant, 8.314 J / (mol-K); is the pressure of the gas, unit: Pa; V is the volume of the gas, unit: m3; S22: by periodic pressure changes filling volume with a gas volume satisfies the following equation: wherein, is the rate of change of the glass filling volume, in m³ / s; k is the glass viscosity coefficient, in m³ / (s·Pa); is the external pressure, in Pa; is the gas pressure, in Pa.

4. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The design of the pressure cycle parameters of step S2 comprises: the flow Q of gas discharged through depressurization follows the Poiseuille law, and the formula is: wherein, is the pore radius, in m; is the gas viscosity, in Pa-s; is the pore length, in m; is the number of pores; is the gas pressure change; Pressure relief time Must satisfy: wherein is the atmospheric pressure, in Pa; Based on gas residual amount threshold , cycle number satisfies: wherein, V0 is the initial gas volume in the mold cavity.

5. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The gas pressure-deformation coupling compensation model of step S3 is: wherein, is the compensated profile height, unit: pm; is the measured profile height of the workpiece, unit: pm; is the CAD model data, unit: pm; is the air pressure difference during the molding process, unit: kPa; is the air pressure deformation coefficient, unit: pm / (kPa pm-1); is the mold profile curvature, unit: pm-1.

6. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The calculation of the compensation amount of each unit cell of step S3 comprises: measuring the measured profile height of a single unit cell and the corresponding CAD model data, calculating the spatial error of the measured data and the design data, eliminating the coordinate system error caused by clamping and measurement position offset, and realizing spatial alignment; The profile deviation of each coordinate point is calculated: wherein, CAD model data, unit: μm; Workpiece measured profile height, unit: μm; The corresponding parameters are introduced into the air pressure-deformation coupling compensation equation to calculate the additional amount of each cell.

7. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 1, characterized in that, The conversion of the compensation amount into the grinding head feed amount of step S3 comprises: converting the compensation amount into grinding depth data in the grinding machine coordinate system, i.e. the grinding head feed amount; and generating a processing path according to the grinding depth data.

8. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to claim 7, characterized in that, The specific calculation formula for converting the compensation amount into the grinding head feed amount is: Wherein, is the feed amount of the grinding head, unit: μm; is the included angle of the grinding edge, the value range is 55°-75°; is the material resilience coefficient, the tungsten steel takes 0.02-0.05; is the grinding temperature, the temperature is controlled below 150℃.

9. The glass micro-matrix molding and compensation processing method based on air pressure dynamic balance according to any one of claims 1-8, characterized in that, Step S3 further comprises online real-time correction of the grinding head feed amount, and the correction formula is: wherein, is the final grinding feed amount, unit: μm; is the air pressure gain coefficient, the value range is 0.1-0.3; is the standard working condition air pressure, the standard working condition air pressure is a set value; is the air pressure change value.

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