Processing technology and processing system for micro-lens array on inner surface of hollow cylinder

Abstract

The invention discloses a processing technology and a processing system for a micro-lens array on the inner surface of a hollow cylinder. The processing technology for the micro-lens array on the inner surface of the hollow cylinder comprises the following steps: S10, confirming that a morphological feature is within a servo processing range of a two-dimensional elliptical vibration device; s20, a processing system is built; s30, tool parameters and cutting parameters are obtained; s40, a servo track of the two-dimensional elliptical vibration device and X-axis and Z-axis motion paths of the machine tool are generated; s50, machining compensation is determined; and S60, the machining system is started for machining. The processing system is used for the processing technology of the micro-lens array on the inner surface of the hollow cylinder. According to the hollow cylinder inner surface micro-lens array machining process and machining system, the micro-lens array with the free-form surface morphology is machined on the cylinder inner surface, machining of a three-dimensional structure can be completed, the machining surface type precision is high, the surface roughness reaches the nanometer level, and various materials can be machined.

Description

Technical Field

[0001] The invention relates to the technical field of ultra-precision machining, and in particular to a machining process and a machining system for a microlens array on the inner surface of a hollow cylinder. Background Art

[0002] Nowadays, microstructure arrays are a type of surface with regularly distributed microscopic geometric topological shapes and specific functions. They are key components in optoelectronics, information communication, precision engineering and other fields, such as microlens arrays for IC equipment light source systems, bionic compound eye structure arrays for target positioning, and microprism arrays for spatial optics. It is worth noting that due to the limitations of the manufacturing process, most of the previous microlens arrays could only be generated on a plane. In recent years, inspired by various compound eye structures in nature, people have gradually realized that microlens arrays on curved surfaces have better performance than planar structures. For example, spherical compound eye structures are closer to real compound eyes in nature than planar compound eye structures, with a larger field of view and high sensitivity. Therefore, it is particularly important to seek to quickly and accurately generate microlens arrays with free-form surface morphology on curved substrates.

[0003] In recent years, in order to meet the requirements of morphology and precision of microlens arrays on curved substrates in industrial production, some manufacturing technologies for microstructured surfaces have been proposed, including photolithography, energy beam manufacturing, special energy field processing, and ultra-precision machining based on diamond tools, etc. Each method has its own unique advantages and disadvantages.

[0004] Among them, photolithography is a technology that uses exposure and etching methods to transfer the plane geometric model on the mask plate to the surface of a single crystal or the substrate layer to form a geometric figure. Mohammad J. Moghimi et al. used photolithography to manufacture extremely high-resolution Fresnel lens arrays on the inner and outer surfaces of cylinders. Huan Hu et al. used nanolithography to process microlenses on the outer surface of glass and silicon substrate cylinders, with a characteristic size of about 250nm.

[0005] However, the existing photolithography technology also has significant disadvantages. The equipment cost is extremely high, and it is usually only used for the microstructure manufacturing of binary structures. It is not suitable for the processing and preparation of three-dimensional complex structures, especially three-dimensional free-form surface structures, and it also has strong constraints on the materials that can be processed. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the existing photolithography technology is costly and can only be used for binary structures. The purpose is to provide a hollow cylindrical inner surface microlens array processing technology and processing system to solve the above problem.

[0007] The present invention is achieved through the following technical solutions:

[0008] In a first aspect, the present invention discloses a process for processing a microlens array on the inner surface of a hollow cylinder, comprising the following steps:

[0009] S10: Design the free-form surface equation of the microlens array on the inner surface of the hollow cylinder based on the product optical performance requirements, and confirm that the morphological features are within the servo processing range of the two-dimensional elliptical vibration device based on the free-form surface equation of the microlens array;

[0010] S20: Build processing system;

[0011] S30: obtaining tool parameters and cutting parameters based on material cutting performance and fly cutter processing characteristics;

[0012] S40: Based on S10 and S20 and influencing factors, the servo trajectory of the two-dimensional elliptical vibration device and the motion paths of the X-axis and Z-axis of the machine tool are generated;

[0013] S50: Determine machining compensation based on the turning radius of the fly cutter cutting and the starting position of the tool tip in the machine tool coordinate system;

[0014] S60: Start the processing system and perform processing.

[0015] In one possible design, in S10, a single free-form surface lens includes an aspherical surface z1 and a spherical surface z2, and the equation is described as:

[0016]

[0017] f(x,y)=z1(x,y)+z2(x,y)

[0018] In the formula, h, k1, c1, R c , s1, s2 are all constants, and h=0.0025, k1=-0.5, c1=0.8, R c =0.3, s1=0.0081, s2=2.5, A represents the first aspheric coefficient; B represents the second aspheric coefficient; f(x, y) represents the free-form surface equation of the microlens array.

[0019] In a possible design, in S20, the tool parameters include the radius, rake angle and back angle of the tool tip; and the cutting parameters include the spindle speed, feed rate and cutting depth.

[0020] In one possible design, S30 includes the following steps:

[0021] S41: The free-form surface equation of the microlens array f(x, y) in the interval (θ min ,θ max ) is linearly discretized into N+1 points;

[0022] S42: Based on workpiece coordinate system Ow x w y w z w , obtain the coordinates (x tw ,y tw , z tw ) and the tangent vector at point n

[0023]

[0024] In the formula, θ i represents the angle corresponding to the i-th tool contact point on the cutting edge; i represents the i-th tool contact point on the cutting edge;

[0025] S43: The coordinates of point m on the workpiece corresponding to point n are Normal vector at point m

[0026]

[0027] β=-tan -1 (slope(i))

[0028] In the formula, β represents the angle of rotation around the z-axis;

[0029] S44: The tangent vector of the actual cutting point on the cutting edge is perpendicular to the normal vector of the corresponding point on the design surface, that is, By searching all points on the cutting edge, the minimum value θ is obtained i value and determine the actual cutting point.

[0030] In a possible design, in S30, the influencing factors include tool radius compensation, material springback effect and kinematic relationship.

[0031] In a possible design, in S40, based on the machine tool coordinate system O s x s y x z x , obtain the starting position of the tool tip in the machine tool coordinate system (R s , γ0); Based on the starting position of the tool tip, angle compensation is performed in the servo trajectory of the two-dimensional elliptical vibration device.

[0032] In a possible design, in S40, the turning radius of the fly cutter is obtained based on the fly cutter grooving experiment; when the fly cutter is assembled, the deviation angle of the fly cutter is roughly aligned and estimated based on the tool microscope; and compensation correction is performed through cutting experiments.

[0033] In a possible design, in S50, the diamond tool is set on a flying cutter disc, the flying cutter disc is adsorbed on the machine tool spindle through an air suction cup, and the workpiece is fixed on a two-dimensional elliptical vibration device.

[0034] In one possible design, in S60, the machine tool spindle drives the diamond tool to rotate, and the machine tool X-axis and Z-axis perform feed motion respectively; based on the machine tool spindle position, the two-dimensional elliptical vibration device servo corresponds to the trajectory and controls the workpiece to move in the vertical direction.

[0035] In a second aspect, the present invention discloses a processing system for the hollow cylindrical inner surface microlens array processing technology, comprising a machine tool, a flying cutter disc, a diamond tool, a vertical motion platform, a two-dimensional elliptical vibration device and a control module;

[0036] The machine tool has an X-axis, a Z-axis and a spindle, the X-axis is provided with a base for mounting the spindle, and the Z-axis is located outside the X-axis and perpendicular to the X-axis;

[0037] The flying cutter disc is adsorbed on the machine tool spindle through an air suction cup, and the diamond tool is set on the flying cutter disc;

[0038] The vertical motion platform is arranged on the Z axis and can reciprocate along the Z axis, and the two-dimensional elliptical vibration device is arranged on the vertical motion platform and is used to place the workpiece;

[0039] The control module is electrically connected to and controls the machine tool, the flying cutter disc, the diamond cutter, the vertical motion platform and the two-dimensional elliptical vibration device.

[0040] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0041] It can realize the processing of free-form microlens array on the inner surface of the cylinder, and can complete the processing of three-dimensional structure, with high surface accuracy, surface roughness reaching nanometer level, and various materials can be processed;

[0042] The diamond cutting process that uses flying cutter cutting and two-dimensional elliptical vibration to control cutting parameters and tool parameters can improve cutting stability, traverse the designed complex cutting trajectory, and achieve ultra-precision machining of complex surfaces. The complexity of generating microstructures on the inner surface of the cylinder by traditional fast tool servo and slow tool servo methods is reduced, and the surface quality and performance of the lens array are well guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0044] Figure 1 A structural diagram of a processing system.

[0045] Figure 2 Schematic diagram of the basic principle of flying knife-two-dimensional elliptical vibration.

[0046] Figure 3 Schematic diagram of servo trajectory calculation for a two-dimensional elliptical vibration device.

[0047] Marks and corresponding parts names in the attached drawings:

[0048] 1. Machine tool; 2. Flying cutter disc; 3. Diamond tool; 4. Vertical motion platform; 5. Two-dimensional elliptical vibration device. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0050] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0051] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0052] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0053] Embodiment 1:

[0054] like Figure 1-Figure 3 As shown, a hollow cylindrical inner surface microlens array processing technology includes the following steps:

[0055] S10: designing a free-form surface equation of a microlens array on the inner surface of a hollow cylinder based on the optical performance requirements of the product, and confirming that the morphological feature is within the servo processing range of the two-dimensional elliptical vibration device 5 based on the free-form surface equation of the microlens array;

[0056] S20: Build processing system;

[0057] S30: obtaining tool parameters and cutting parameters based on material cutting performance and fly cutter processing characteristics;

[0058] S40: Based on S10 and S20 and influencing factors, the servo trajectory of the two-dimensional elliptical vibration device 5 and the X-axis and Z-axis motion paths of the machine tool 1 are generated;

[0059] S50: Determine machining compensation based on the turning radius of the fly cutter cutting and the starting position of the tool tip in the coordinate system of the machine tool 1;

[0060] S60: Start the processing system and perform processing.

[0061] In the hollow cylinder inner surface microlens array processing technology, in S10, the servo processing range of the two-dimensional elliptical vibration device 5 is known. By obtaining the free-form surface equation of the microlens array on the inner surface of the hollow cylinder, the design value required for the product to form a free-form surface morphological feature in a single processing process can be confirmed. The design value is also the required servo processing range of the two-dimensional elliptical vibration device 5. By comparing the design value with the known value, it can be confirmed that the morphological feature is within the servo processing range of the two-dimensional elliptical vibration device 5.

[0062] If the processing requirements are met, the corresponding two-dimensional elliptical vibration device 5 is used, and the subsequent process is continued; if the processing requirements are not met, a two-dimensional elliptical vibration device 5 of another type is replaced until the requirements are met.

[0063] In S20, the processing system is built, and in the subsequent process of determining the processing parameters, the processing system can be directly debugged, or a trial run is performed through the processing system to facilitate timely adjustments.

[0064] In S30, appropriate tool parameters and appropriate cutting parameters are selected based on the material cutting performance and the fly cutter processing characteristics to ensure the quality of the processed surface.

[0065] In S40, the trajectory of each moving component in the processing system is confirmed, and the feed motion of each moving component is controlled and coordinated through the control module to complete the processing of specific morphological features, thereby achieving automated processing while ensuring processing quality.

[0066] In S50, the processing parameters are further determined, and the errors of the processing system are eliminated through processing compensation to ensure the quality of the processed surface. At the same time, since the processing system has been built, debugging is directly performed on the processing system to eliminate errors and achieve compensation.

[0067] In S60, relevant preparations have been completed, and the processing system can be started for processing.

[0068] Specifically:

[0069] In a possible implementation, in S10, a single free-form surface lens includes an aspherical surface z1 and a spherical surface z2, and the equation is described as:

[0070]

[0071] f(x,y)=z1(x,y)+z2(x,y)

[0072] In the formula, h, k1, c1, R c , s1, s2 are all constants, and h=0.0025, k1=-0.5, c1=0.8, R c =0.3, s1=0.0081, s2=2.5, A represents the first aspheric coefficient; B represents the second aspheric coefficient; f(x, y) represents the free-form surface equation of the microlens array.

[0073] Based on the above design scheme, based on the respective representation equations of the aspheric surface z1 and the spherical surface z2, the free-form surface equation of the microlens array can be obtained, and the free-form surface equation of the microlens array is compared with the processing range of the processing system. If it is within the processing range of the processing system, it can be processed by the processing system. Otherwise, if it is outside the processing range of the processing system, replace other models of processing systems to complete the processing.

[0074] In a possible implementation, in S20 , the diamond tool 3 is disposed on the fly cutter disc 2 , the fly cutter disc 2 is adsorbed on the main shaft of the machine tool 1 through an air suction cup, and the workpiece is fixed on the two-dimensional elliptical vibration device 5 .

[0075] Based on the above design scheme, other parts of the machine tool 1 have been connected. According to different processing requirements, any suitable diamond tool 3 is selected. When the diamond tool 3 is used for cutting, compared with other optical or electronic manufacturing methods, its advantage is that it can obtain higher three-dimensional shape accuracy and surface roughness. In addition, it has the ability to manufacture free-form surfaces, which is very important for the manufacture of optical components.

[0076] In a possible implementation, in S30, the tool parameters include the radius, rake angle, and clearance angle of the tool tip; and the cutting parameters include the spindle speed, feed rate, and cutting depth.

[0077] Based on the above design scheme, according to the tool parameters, an appropriate tool is selected and installed on the processing system to complete the processing with the selected tool. According to the specific model of the tool and the specific processing requirements, the cutting parameters are determined. Furthermore, for the tool parameters and cutting parameters, in addition to the parameters listed above, any other suitable parameters can also be included to meet specific processing requirements.

[0078] In a possible implementation, S40 includes the following steps:

[0079] S41: The free-form surface equation of the microlens array f(x, y) in the interval (θ min ,θ max ) is linearly discretized into N+1 points;

[0080] S42: Based on workpiece coordinate system O w x w y w z w , obtain the coordinates (x tw ,y tw , z tw ) and the tangent vector at point n

[0081]

[0082] In the formula, θ i represents the angle corresponding to the i-th tool contact point on the cutting edge; i represents the i-th tool contact point on the cutting edge;

[0083] S43: The coordinates of point m on the workpiece corresponding to point n are Normal vector at point m

[0084]

[0085] B=-tan -1 (slope(i))

[0086] In the formula, β represents the angle of rotation around the z-axis;

[0087] S44: The tangent vector of the actual cutting point on the cutting edge is perpendicular to the normal vector of the corresponding point on the design surface, that is, By searching all points on the cutting edge, the minimum value θ is obtained i value and determine the actual cutting point.

[0088] Based on the above design scheme, the processing system realizes processing through a single-point diamond cutting process. However, in this process, the actual cutting edge contact point always changes, and the radius of the tool also affects the processing quality.

[0089] For the actual cutting edge contact point, such as Figure 3 As shown, there are three coordinate systems in the machining system: tool coordinate O t x t y t z t , located on the rake face of the diamond tool, is used to describe the cutting edge morphology of the diamond tool; the spindle coordinate system is O s x s y x z x , located at the center of the machine tool spindle; the workpiece coordinate system is O w x w y w z w , on the workpiece surface.

[0090] On the basis of the above three coordinate systems, accurate numerical calculations are performed through S41-S44 to obtain all actual cutting points, so that the processing parameters are more accurate, the processed morphological features are more accurate, and the processing quality of the processing system is higher.

[0091] In a possible implementation, in S40, the influencing factors include tool radius compensation, material rebound effect and kinematic relationship. Based on the above design scheme, combined with the actual cutting points obtained in S41-S44, the servo trajectory of the two-dimensional elliptical vibration device 5 and the X-axis and Z-axis motion paths of the machine tool are generated. Further, for the influencing factors, in addition to the parameters listed above, any other suitable parameters can also be included to meet specific processing requirements.

[0092] In a possible implementation, in S50, based on the machine tool coordinate system O s x s y x z x, obtain the starting position of the tool tip in the machine tool coordinate system (R s , γ0); based on the starting position of the tool tip, angle compensation is performed in the servo trajectory of the two-dimensional elliptical vibration device 5.

[0093] Based on the above design scheme, when the tool is installed, the tool is fixed on the main shaft of the machine tool 1 and is parallel to the horizontal axis of the machine tool 1. However, due to the installation error, there is a deviation angle after the tool is installed. Using a tool setting microscope during installation can reduce the value of the deviation angle, but it cannot eliminate the deviation angle. Therefore, the deviation angle is further reduced by angle compensation. Based on the servo trajectory of the two-dimensional elliptical vibration device 5 obtained in S40, any suitable existing method can be used for compensation.

[0094] In a possible implementation, in S50, based on the fly cutter grooving experiment, the fly cutter turning radius is obtained; when the fly cutter is assembled, the fly cutter deviation angle is roughly aligned and estimated based on the tool setting microscope; and compensation correction is performed through the cutting experiment;

[0095] Based on the above design scheme, taking the established processing system as a benchmark, the processing parameters, such as the flying cutter rotation radius, are obtained through actual processing. At the same time, debugging is also carried out through cutting experiments to reduce the deviation angle.

[0096] Optionally, during the flying cutter grooving experiment, the curvature radius of the groove is measured by a white light interferometer to obtain the flying cutter rotation radius.

[0097] In a possible implementation, in S60, the spindle of the machine tool 1 drives the diamond tool 3 to rotate, and the X-axis and Z-axis of the machine tool 1 perform feed motion respectively; based on the spindle position of the machine tool 1, the two-dimensional elliptical vibration device 5 servos the corresponding trajectory and controls the workpiece to move in the vertical direction.

[0098] Based on the above design scheme, the X-axis, Z-axis and two-dimensional elliptical vibration device 5 of the machine tool 1 cooperate with each other to complete the processing of the workpiece, assisted by the two-dimensional elliptical vibration device 5 servo corresponding trajectory and control the movement of the workpiece in the vertical direction, to achieve the processing and preparation of three-dimensional complex structures, expand the processing range, and improve practicality.

[0099] Based on the above-mentioned hollow cylinder inner surface microlens array processing technology, this embodiment introduces a processing system for the above-mentioned hollow cylinder inner surface microlens array processing technology, and the processing system includes a machine tool 1, a flying cutter disk 2, a diamond tool 3, a vertical motion platform 4, a two-dimensional elliptical vibration device 5 and a control module;

[0100] The machine tool 1 has an X-axis, a Z-axis and a spindle, the X-axis is provided with a base for mounting the spindle, and the Z-axis is located outside the X-axis and perpendicular to the X-axis;

[0101] The flying cutter disc 2 is adsorbed on the main shaft of the machine tool 1 through an air suction cup, and the diamond tool 3 is arranged on the flying cutter disc 2;

[0102] The vertical motion platform 4 is arranged on the Z axis and can reciprocate along the Z axis, and the two-dimensional elliptical vibration device 5 is arranged on the vertical motion platform 4 and is used to place the workpiece;

[0103] The control module is electrically connected to and controls the machine tool 1 , the flying cutter disc 2 , the diamond tool 3 , the vertical motion platform 4 and the two-dimensional elliptical vibration device 5 .

[0104] In the processing system, the machine tool 1 can be any suitable existing model, and the flying cutter disc 2 and the diamond tool 3 are both detachably connected to facilitate the replacement of the diamond tool 3 to meet the corresponding processing requirements. The vertical motion platform 4 is connected to the two-dimensional elliptical vibration device 5 to fix the position of the workpiece through the two-dimensional elliptical vibration device 5. At the same time, the vertical motion platform 4 can be raised and lowered, which is used for the disassembly and assembly of the workpiece on the one hand, and can also adjust the workpiece to a suitable height before processing the workpiece on the other hand.

[0105] The two-dimensional elliptical vibration device 5 obtains the spindle output data of the machine tool 1 through the control module, and then obtains the real-time position of the spindle. Based on the real-time position of the spindle, the two-dimensional elliptical vibration device 5 servos the corresponding trajectory and controls the workpiece to move in the vertical direction, and finally forms a lens array with a free-form surface morphology.

[0106] Correspondingly, the two-dimensional elliptical vibration device 5 is provided with components such as a capacitive displacement sensor and a piezoelectric ceramic driver, wherein the capacitive displacement sensor is used to obtain the spindle output data of the machine tool 1 and transmit it to the control module, and the piezoelectric ceramic driver makes the two-dimensional elliptical vibration device 5 servo the trajectory of the spindle according to the instructions of the control module.

[0107] It is easy to understand that in the processing system, the moving parts include the movements of the X-axis, Z-axis and main spindle mainly based on the machine tool 1, and the movement mainly based on the two-dimensional elliptical vibration device 5. The control module can electrically connect the two at the same time and control their operation; or, the control module includes two sub-units, each sub-unit is electrically connected to one of the machine tool 1 and the two-dimensional elliptical vibration device 5 and controls its operation.

[0108] Embodiment 2:

[0109] This embodiment provides a practical processing scheme based on embodiment 1:

[0110] The workpiece material is copper or aluminum, and the microstructure feature size is within 70μm.

[0111] The stiffness of the two-dimensional elliptical vibration device 5 in the X-direction and the Y-direction are 16.37 N / μm and 9.10 N / μm respectively, and the displacement is 75 μm and 90 μm. The structural dimension characteristics of the workpiece are within the processing capability of the two-dimensional elliptical vibration device 5 .

[0112] Based on the hollow cylindrical inner surface microlens array processing technology in Example 1, the spindle speed is 30 rpm, the tool tip radius is 0.2 mm, and the Z-direction feed amount is 5 μm, so as to realize a high-precision free-form surface microlens array.

[0113] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A process for processing a microlens array on the inner surface of a hollow cylinder, characterized in that: The following steps are involved: S10: designing a free-form surface equation of a microlens array on the inner surface of a hollow cylinder based on the optical performance requirements of the product, and confirming that the morphological features are within the servo processing range of the two-dimensional elliptical vibration device (5) based on the free-form surface equation of the microlens array; S20: Build processing system; S30: obtaining tool parameters and cutting parameters based on material cutting performance and fly cutter processing characteristics; S40: Based on S10 and S20 and influencing factors, a servo trajectory of the two-dimensional elliptical vibration device (5) and the X-axis and Z-axis motion paths of the machine tool (1) are generated; S50: Determine machining compensation based on the turning radius of the fly cutter cutting and the starting position of the tool tip in the coordinate system of the machine tool (1); S60: Start the processing system and perform processing.

2. The hollow cylinder inner surface microlens array processing technology according to claim 1, characterized in that: In S10, a single free-form surface lens includes an aspherical surface z1 and a spherical surface z2, and the equation is described as: f(x,y)=z1(x,y)+z2(x,y) In the formula, h, k1, c1, R c , s1, s2 are all constants, and h=0.0025, k1=-0.5, c1=0.8, R c =0.3, s1=0.0081, s2=2.5, A represents the first aspheric coefficient; B represents the second aspheric coefficient; f(x, y) represents the free-form surface equation of the microlens array.

3. The hollow cylinder inner surface microlens array processing technology according to claim 2, characterized in that: In S20, the diamond tool (3) is arranged on the flying cutter disc (2), the flying cutter disc (2) is adsorbed on the main shaft of the machine tool (1) through an air suction cup, and the workpiece is fixed on the two-dimensional elliptical vibration device (5).

4. The hollow cylinder inner surface microlens array processing technology according to claim 3, characterized in that: In S30, the tool parameters include the radius, rake angle and back angle of the tool tip; and the cutting parameters include the spindle speed, feed rate and cutting depth.

5. The process for processing a microlens array on the inner surface of a hollow cylinder according to any one of claims 1 to 4, characterized in that: S40 includes the following steps: S41: The free-form surface equation of the microlens array f(x, y) in the interval (θ min ,θ max ) is linearly discretized into N+1 points; S42: Based on workpiece coordinate system O w x w y w z w , obtain the coordinates of the cutting edge at any point n in the workpiece coordinate system (x tw ,y tw , z tw ) and the tangent vector at point n In the formula, θ i represents the angle corresponding to the i-th tool contact point on the cutting edge; i represents the i-th tool contact point on the cutting edge; S43: The coordinates of point m on the workpiece corresponding to point n are Normal vector at point m β=-tan -1 (slope(i)) In the formula, β represents the angle of rotation around the z-axis; S44: The tangent vector of the actual cutting point on the cutting edge is perpendicular to the normal vector of the corresponding point on the design surface, that is, By searching all points on the cutting edge, the minimum value θ is obtained i value and determine the actual cutting point.

6. The process for processing a microlens array on the inner surface of a hollow cylinder according to claim 5, characterized in that: In S40, the influencing factors include tool radius compensation, material springback effect and kinematic relationship.

7. The process for processing a microlens array on the inner surface of a hollow cylinder according to claim 6, characterized in that: In S50, based on the machine tool coordinate system O s x s y x z x , obtain the starting position of the tool tip in the machine tool coordinate system (R s , γ0); based on the starting position of the tool tip, angle compensation is performed in the servo trajectory of the two-dimensional elliptical vibration device (5).

8. The process for processing a microlens array on the inner surface of a hollow cylinder according to claim 6 or 7, characterized in that: In S50, the turning radius of the fly cutter is obtained based on the fly cutter grooving experiment; when the fly cutter is assembled, the deviation angle of the fly cutter is roughly aligned and estimated based on the tool setting microscope; and compensation correction is performed through the cutting experiment.

9. The process for processing a microlens array on the inner surface of a hollow cylinder according to claim 8, characterized in that: In S60, the main shaft of the machine tool (1) drives the diamond tool (3) to rotate, and the X-axis and Z-axis of the machine tool (1) respectively perform feeding motion; based on the main shaft position of the machine tool (1), the two-dimensional elliptical vibration device (5) serves the corresponding trajectory and controls the workpiece to move in the vertical direction.

10. A processing system for the processing technology of the microlens array on the inner surface of a hollow cylinder according to any one of claims 1 to 9, characterized in that: It comprises a machine tool (1), a flying cutter disc (2), a diamond tool (3), a vertical motion platform (4), a two-dimensional elliptical vibration device (5) and a control module; The machine tool (1) has an X-axis, a Z-axis and a spindle, the X-axis is provided with a base for mounting the spindle, and the Z-axis is located outside the X-axis and perpendicular to the X-axis; The flying cutter disc (2) is adsorbed on the main shaft of the machine tool (1) through an air suction cup, and the diamond tool (3) is arranged on the flying cutter disc (2); The vertical motion platform (4) is arranged on the Z axis and is capable of reciprocating along the Z axis, and the two-dimensional elliptical vibration device (5) is arranged on the vertical motion platform (4) and is used to place the workpiece; The control module is electrically connected to and controls the machine tool (1), the flying cutter disc (2), the diamond tool (3), the vertical motion platform (4) and the two-dimensional elliptical vibration device (5).

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