A modeling method for analyzing spherical lens centering and edging outer circle removal amount

Abstract

The application provides a modeling method for analyzing the outer circle removal amount of centering and edging of a spherical lens, which re-describes the center deviation under four spatial position relations between an optical axis and a geometric axis; obtains a new spatial position relation between the optical axis and the geometric axis according to the re-described result; and establishes a model of the center deviation on the outer circle removal amount of the centering and edging process based on the new spatial position relation between the optical axis and the geometric axis. The model is established according to the standardized general process of the application, the spatial position relation between the optical axis and the geometric axis of various spherical lenses can be clearly obtained, the corresponding relation between the center deviation and the grinding amount in the front and rear and upper and lower directions of the centering and edging process of the spherical lens can be clearly and orderly obtained, and the accurate outer circle removal amount is obtained, thereby providing theoretical support for the quality problems such as the outer circle diameter being lower than the lower limit of the design index and the edge collapse entering the optical surface due to the excessive outer circle removal amount.

Description

Technical Field

[0001] This invention relates to the field of optical processing technology for spherical optical elements, and in particular to a modeling method for analyzing the amount of material removed from the outer diameter of a spherical lens during centering and edge grinding. Background Technology

[0002] The traditionally defined center deviation represents the degree of deviation between the geometric axis of the outer circle of a spherical lens and the optical axis at the center of the lens's curvature, denoted by C. Figure 1 As shown. However, it cannot represent the general situation of the spatial relative positions of the optical axis and the geometric axis. In the new national standard GB7242-87, my country has proposed a new term and definition, namely, center error.

[0003] The center error is the deviation of the normal at the centering vertex of an optical surface from the reference axis. It is measured by the angle between the normal at the centering vertex and the reference axis, and this angle is called the surface tilt angle, denoted by the Greek letter χ. The corresponding distance from the center of the sphere to the geometric axis is the center axis distance a, such as... Figure 2 As shown, while center error or surface tilt clearly represents the degree of deviation between the center of a spherical lens and its geometric axis on a specific optical surface, it still cannot intuitively reflect the spatial relationship between the lens's geometric axis and optical axis. Center deviation or center error is a very important optical design parameter for spherical lenses, aiming to make the lens's geometric axis coincide with the optical axis as much as possible to ensure the assembly and adjustment accuracy of the optical system.

[0004] The ideal situation in design is for the geometric axis to coincide with the optical axis. However, in the actual lens manufacturing process, tooling errors, operational errors, etc., will inevitably be introduced. The superposition of these errors results in the actual center deviation of the spherical lens.

[0005] In the rough and fine grinding processes of spherical lenses, the center deviation cannot be directly measured. Its accuracy is generally ensured indirectly by controlling the edge thickness difference of the lens and the accuracy of conversion indicators such as the runout of the spherical surface relative to the end face. In the polishing and mounting process, certain positioning measures can also be taken to minimize the center deviation. After polishing, the position of the sphere center relative to the geometric axis is fixed, that is, the optical axis is fixed relative to the geometric axis. At this time, there is a certain deviation between the optical axis and the geometric axis. It is necessary to grind the outer circle in the final centering and edge grinding process to make the geometric axis and the optical axis as close as possible to coincide.

[0006] The essence of centering edge grinding is to place the two centers of the lens on the rotation axis of the edge grinding machine through a certain method, that is, to adjust the optical axis as much as possible to coincide with the rotation axis, thereby transforming the edge grinding process based on the optical axis into the process of grinding the outer circle of the lens with the rotation axis of the edge grinding machine as the axis of symmetry.

[0007] However, when there are problems such as large center deviation before lens centering and edge grinding, excessive removal of the outer diameter of the lens, or high hardness of the lens material, the centering and edge grinding process is prone to quality problems such as the outer diameter being lower than the lower limit of the design specification due to excessive removal of the outer diameter, and chipping at the edge grinding position entering the optical surface. Summary of the Invention

[0008] This invention provides a modeling and analysis method for the outer diameter cutting of spherical lenses in centering edge grinding. It is a general method for establishing a spatial model by analyzing the influence of center deviation on the outer diameter removal amount in the centering edge grinding process. By establishing the model according to the standardized general process of this invention, the spatial positional relationship between the optical axis and geometric axis of various spherical lenses (biconvex, biconcave, meniscus, plano-convex, plano-concave) can be clearly obtained. The correspondence between the center deviation and the grinding amount in the four directions (front, back, top, and bottom) of the spherical lens in the centering edge grinding process can be clearly and orderly obtained, and the outer diameter removal amount can be accurately determined. This provides theoretical support for the analysis of quality problems such as the outer diameter being lower than the design specification lower limit and edge chipping entering the optical surface due to excessive outer diameter removal amount.

[0009] In a first aspect, embodiments of the present invention provide a modeling method for analyzing the amount of material removed from the outer diameter of a spherical lens during centering and edge grinding, the modeling method comprising:

[0010] The center deviation between the optical axis and the geometric axis is redescribed under four spatial positional relationships; wherein the four spatial positional relationships include skew plane, parallel, intersecting and coincident.

[0011] Based on the results of the re-description, a new spatial relationship between the optical axis and the geometric axis of the spherical lens is obtained;

[0012] Based on the new spatial relationship between the optical axis and the geometric axis, a model is established for the removal amount of the outer circle in the centering edge grinding process. In this model, the centering edge grinding is performed with the optical axis as the rotation axis and the distance between the grinding wheel and the rotation axis of the machine tool is the cutting rotation radius.

[0013] In the spatial description of the center deviation when the planes are not parallel, the angle between the plane containing the optical axis and the plane containing the geometric axis is defined as α, where α≠0; a perpendicular line is drawn from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; a perpendicular line is drawn from the center of the sphere O1 to the plane passing through the geometric axis and the center of the sphere O2, with the foot of the perpendicular being O1″, and the line segment O1O1″=C, which matches the center deviation under the traditional definition.

[0014] The spatial description of the center deviation at intersection is as follows: the optical axis and the geometric axis intersect and are coplanar. A perpendicular line is drawn from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; a perpendicular line is drawn from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. The length of the line segment O1O1′ = a1, and the length of the line segment O2O2′ = a2. When the centers of the sphere O1 and O2 are located on opposite sides of the geometric axis, the center deviation C = a1 + a2; when the centers of the sphere O1 and O2 are located on the same side of the geometric axis, the center deviation C = |a1 - a2|.

[0015] In the case of coplanarity, the spatial description of the center deviation is as follows: draw a perpendicular line from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. The lengths of the line segments are O1O1′=a1 and O2O2′=a2, and the center deviation C=a1=a2≠0.

[0016] Among them, the spatial description of the center deviation when the optical axis coincides with the geometric axis is that the center deviation C = a1 = a2 = 0.

[0017] As one feasible implementation method, based on the new spatial relationship between the optical axis and the geometric axis, establishing a model for the amount of material removed from the outer diameter of the centering edge grinding process due to the center deviation includes: selecting a spherical lens of a specific shape; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are not parallel; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis intersect; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are parallel; and drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis coincide.

[0018] As one feasible implementation method, based on the new spatial relationship between the optical axis and the geometric axis, a model is established for the effect of center deviation on the amount of material removed from the outer diameter in the centering edge grinding process, including:

[0019] The relative positions of the outer circle removal amount model are established when the optical axis and the geometric axis are not parallel.

[0020] In the front view of the model, the optical axis is translated symmetrically and equally by a distance d in the upper and lower directions of the outer circle to obtain the grinding cutting lines of the outer circle in the upper and lower directions. In the top view of the model, the optical axis is translated equally by a distance d in the front and back directions of the outer circle to obtain the grinding cutting lines of the outer circle in the front and back directions. The part between the four cutting lines and the outer circle boundary is the amount of material removed in the four directions of the lens outer circle, and d is the distance between the grinding wheel and the rotation axis of the machine tool.

[0021] As an achievable implementation method, the outer circle removal amount model satisfies the following two conditions: First, the translation distance of the optical axis in the four directions of up, down, front, and back should be equal to reflect the rotation process centered on the optical axis in the actual centering edge grinding process; Second, the outer circle should be ground in the four directions of up, down, front, and back to represent the outer circle diameter and roundness during centering edge grinding.

[0022] As one feasible implementation, when the optical axis and geometric axis are not parallel, the placement in the outer circle removal amount model is such that the plane parallel to the optical axis is in front and the plane parallel to the geometric axis is behind.

[0023] In a second aspect, embodiments of the present invention provide an optical processing apparatus for spherical optical elements, wherein the processing apparatus applies the modeling method described in the first aspect for analyzing the amount of material removed from the outer circle of a spherical lens during centering and edge grinding.

[0024] Beneficial effects

[0025] This invention provides a general method for establishing a spatial model to analyze the influence of center deviation on the outer diameter removal amount in a centering edge grinding process. The modeling method re-describes the center deviation under four spatial positional relationships between the optical axis and the geometric axis. These four spatial positional relationships include skew, parallel, intersecting, and coincident. Based on the re-description results, a new spatial positional relationship between the optical axis and the geometric axis of the spherical lens is obtained. Based on this new spatial positional relationship, a model is established for the influence of center deviation on the outer diameter removal amount in the centering edge grinding process. In this process, the centering edge grinding is performed with the optical axis as the rotation axis, and the distance between the grinding wheel and the rotation axis of the machine tool is used as the cutting rotation radius. By establishing a model according to the standardized and general process of this invention, the spatial positional relationship between the optical axis and geometric axis of various spherical lenses (biconvex, biconcave, meniscus, plano-convex, plano-concave) can be clearly obtained. The corresponding relationship between the center deviation and the grinding amount in the four directions (front, back, top, and bottom) of the spherical lens in the centering and edge grinding process can be clearly and orderly obtained, and the outer diameter removal amount can be accurately determined. This provides theoretical support for quality problems such as the outer diameter being lower than the design specification lower limit and edge chipping entering the optical surface due to excessive outer diameter removal amount.

[0026] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of the present invention, nor is it intended to restrict the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0027] The above and other features, advantages, and aspects of the various embodiments of the present invention will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements.

[0028] Figure 1This diagram illustrates lens center deviation under the traditional definition.

[0029] Figure 2 This diagram illustrates the central error under my country's new definition.

[0030] Figure 3 This diagram illustrates the center deviation when the optical axis and geometric axis of the present invention are out of plane;

[0031] Figure 4 This diagram illustrates the center deviation when the optical axis and geometric axis of the present invention intersect;

[0032] Figure 5 This diagram illustrates the center deviation when the optical axis and geometric axis of the present invention are parallel.

[0033] Figure 6 This diagram illustrates the maximum included angle when the optical axis and geometric axis of the present invention are in opposite planes;

[0034] Figure 7 This invention illustrates the placement position when the optical axis and the geometric axis are skewed, as specified in this invention.

[0035] Figure 8 This diagram illustrates the amount of outer circle removal when the optical axis and geometric axis of the present invention are out of plane and intersect within the outline of the part in the front view;

[0036] Figure 9 A schematic diagram of the outer circle removal amount is shown when the optical axis and geometric axis of the present invention are not on the same plane and do not intersect within the outline of the part in the front view.

[0037] Figure 10 This diagram illustrates the amount of outer circle removal when the optical axis and geometric axis of the present invention intersect within the outline of the part in the front view;

[0038] Figure 11 This diagram illustrates the amount of outer circle removal when the optical axis and geometric axis of the present invention intersect but do not intersect within the outline of the part in the front view;

[0039] Figure 12 This diagram illustrates the amount of outer circle removal when the optical axis is parallel to the geometric axis of the present invention.

[0040] Figure 13 A schematic diagram of the outer circle removal amount when the optical axis and geometric axis of the present invention coincide is shown. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0042] It should be noted that the embodiments of the present invention are described only to more clearly illustrate the technical solutions of the embodiments of the present invention, and do not constitute a limitation on the technical solutions provided by the embodiments of the present invention.

[0043] The method of this invention for obtaining the outer diameter removal amount in the centering and edging process of a spherical lens involves five steps: selecting a spherical lens of a specific shape; drawing a model of the outer diameter removal amount in the centering and edging process when the optical axis and geometric axis are skew; drawing a model of the outer diameter removal amount in the centering and edging process when the optical axis and geometric axis intersect; drawing a model of the outer diameter removal amount in the centering and edging process when the optical axis and geometric axis are parallel; and drawing a model of the outer diameter removal amount in the centering and edging process when the optical axis and geometric axis coincide. The method of this invention is described below with reference to the accompanying drawings:

[0044] This invention provides a modeling method for analyzing the amount of material removed from the outer diameter of a spherical lens during centering and edge grinding. The modeling method includes:

[0045] S20. The center deviation between the optical axis and the geometric axis is redescribed under four spatial positional relationships; wherein, the four spatial positional relationships include skew plane, parallel, intersecting and coincident.

[0046] S40. Based on the results of the re-description, obtain the new spatial relationship between the optical axis and the geometric axis of the spherical lens;

[0047] S60. Based on the new spatial positional relationship between the optical axis and the geometric axis, establish a model of the removal amount of the outer circle in the centering edge grinding process, wherein the centering edge grinding is performed with the optical axis as the rotation axis and the distance between the grinding wheel and the rotation axis of the machine tool is the cutting rotation radius.

[0048] Specifically, the optical axis and the geometric axis are two straight lines in three-dimensional space. Two straight lines in space can have four positional relationships: skew lines that never intersect, parallel lines, intersecting lines, and coincident lines, such as... Figure 3 , Figure 4 , Figure 5 As shown. This invention defines a spatial description of the center deviation between the optical axis and the geometric axis in four spatial positions, as described below:

[0049] 1) Spatial description of center deviation when the planes are not parallel.

[0050] When the optical axis and the geometric axis are skewed, the center deviation cannot be represented by a specific numerical value. In this case, the geometric axis and the optical axis exhibit a certain degree of torsion in space, such as... Figure 3 As shown. There is one and only one plane passing through the center O1 of the sphere and the geometric axis, and one and only one plane passing through the center O2 of the sphere and the geometric axis. The angle between the two planes is defined as α, where α ≠ 0; when the optical axis and the geometric axis are coplanar, i.e., intersecting, parallel, or coincident, α = 0. Draw a perpendicular line from the center O1 of the sphere to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center O1 of the sphere to the plane passing through the geometric axis and the center O2 of the sphere, with the foot of the perpendicular being O1″. Draw a perpendicular line from the center O2 of the sphere to the geometric axis, with the foot of the perpendicular being O2′. Figure 3 Line segment lengths O1O1′=a1, O2O2′=a2, and Figure 2 The center axis distance 'a' in the diagram of the central error under my country's new definition matches. Additionally, Figure 3 The arrow in the diagram points in the direction of the front view through the plane between the center of the sphere O2 and the geometric axis. Figure 3 Front view and Figure 1 (The diagram showing lens center deviation under the traditional definition) is exactly the same. Figure 3 Line segment O1O1″ = C, and Figure 1 The center deviation C in the model matches.

[0051] 2) Spatial description of the center deviation when intersecting.

[0052] The optical axis and the geometric axis intersect and are coplanar, such as... Figure 4 As shown. Draw a perpendicular line from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. Figure 4 The lengths of line segments O1O1′ and O2O2′ are a1 and a2, respectively. Figure 2 The center axis distance 'a' in the diagram of the new definition of center error in my country matches. When the center of the sphere is on both sides of the geometric axis, the center deviation C = a1 + a2; when the center of the sphere is on the same side of the geometric axis, the center deviation C = |a1 - a2|.

[0053] 3) Spatial description of center deviation when parallel.

[0054] The optical axis is parallel and coplanar with the geometric axis, such as... Figure 5 As shown. Draw a perpendicular line from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. Figure 5 The lengths of line segments O1O1′ and O2O2′ are a1 and a2, respectively. Figure 2 The center axis distance 'a' in the diagram of the new definition of center error in my country matches. At this time, the center deviation C = a1 = a2 ≠ 0.

[0055] 4) Spatial description of center deviation when they coincide.

[0056] When the optical axis coincides with the geometric axis, the center deviation C = a1 = a2 = 0.

[0057] Preferably, based on the new spatial relationship between the optical axis and the geometric axis, establishing a model for the amount of material removed from the outer diameter of the centering edge grinding process due to the center deviation includes: selecting a spherical lens of a specific shape; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are not parallel; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis intersect; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are parallel; and drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis coincide.

[0058] Specifically, this invention describes a general method for establishing a spatial model of the influence of center deviation on the amount of material removed from the outer diameter of a spherical lens in a centering edge grinding process under four spatial positional relationships (skew planes, intersecting, parallel, and coincident).

[0059] 1) Select a specific shape of spherical lens type.

[0060] Spherical lenses can be classified into biconvex, biconcave, meniscus, plano-convex, and plano-concave types according to their shape. Choose one of these shapes for your spherical lens.

[0061] 2) Establishment of a model for the removal amount of the outer circle in the centering grinding process based on the center deviation between the optical axis and the geometric axis under four spatial positional relationships.

[0062] ① When the optical axis and the geometric axis are not parallel, establish the relative position of the outer circle removal amount model.

[0063] This invention specifies a unique relative position that is easy to describe when the optical axis and the geometric axis are not in the same plane.

[0064] ② Requirements and methods for drawing the model of the amount of material removed from the outer circle during centering and grinding.

[0065] When obtaining the model of the outer diameter removal amount, the following two requirements must be met: First, the translation distance of the optical axis in the four directions of up, down, front, and back should be equal, reflecting the rotation process centered on the optical axis in the actual centering edge grinding process; Second, the outer diameter should be ground in the four directions of up, down, front, and back, representing the outer diameter and roundness during centering edge grinding.

[0066] Centered edge grinding uses the optical axis as the rotation axis. The distance between the grinding wheel and the machine tool's rotation axis is d, and the radius of rotation for cutting is d. In the front view of the model, translating the optical axis symmetrically and equally by a distance d in the upper and lower directions of the outer circle yields the outer circle grinding cutting lines in the upper and lower positions. In the top view of the model, translating the optical axis equally by a distance d in the front and rear directions of the outer circle yields the outer circle grinding cutting lines in the front and rear positions. The portions between the four cutting lines and the outer circle boundary represent the removal amount in the four positions of the lens's outer circle.

[0067] Drawing the amount of material removed by grinding the outer circle of a spherical lens in four directions under four different spatial relationships.

[0068] The method of the present invention will now be described with reference to the accompanying drawings:

[0069] 1. A biconvex spherical lens is selected as a case study.

[0070] 2. Model drawing of the influence of center deviation on the outer diameter removal amount in the centering grinding process when the optical axis and geometric axis are not on the same plane.

[0071] The relative positions of the model are established when the optical axis and the geometric axis are not on the same plane.

[0072] When the optical axis and the geometric axis are skew, there is one and only one set of parallel planes passing through the optical axis and the geometric axis respectively. Projecting any one axis onto another parallel plane results in the largest angle between the two axes. Let the distance between the two planes be z. Figure 6 As shown.

[0073] To clearly see the amount of outer circle removal in the four directions (front, back, left, right) of the spherical lens, this invention specifies the placement position in the model when the optical axis and geometric axis are not in the same plane. Figure 6 Rotate about the geometric axis so that the plane parallel to the optical axis is in front and the plane parallel to the geometric axis is behind, such as... Figure 7 As shown.

[0074] A model is established to determine the amount of material removed from the outer diameter during centering grinding when the optical axis and geometric axis are not aligned.

[0075] There are two cases where the planes are not parallel:

[0076] a. The optical axis and the geometric axis intersect within the outline of the part in the front view.

[0077] b. The optical axis and the geometric axis do not intersect within the outline of the part in the front view.

[0078] When the optical axis and the geometric axis are not parallel and intersect within the outline of the part in the front view, the schematic diagram of the removal amount of the outer circle of the spherical lens is as follows. Figure 8 As shown. When the optical axis and geometric axis are not parallel and do not intersect within the outline of the part in the front view, the schematic diagram of the removal amount of the outer circle of the spherical lens is as follows. Figure 9 As shown.

[0079] In the model, centering grinding is performed with the optical axis as the rotation axis. The distance between the grinding wheel and the machine tool's rotation axis is d, and the rotation radius of the cutting is d. In the front view, translating the optical axis O1O2 symmetrically and equally by a distance d in the upper and lower directions of the outer circle yields the outer circle grinding cutting lines in the upper and lower positions. In the top view, translating the optical axis O1O2 equally by a distance d in the front and back directions of the outer circle yields the outer circle grinding cutting lines in the front and back positions. The portion between the four cutting lines and the outer circle boundary represents the removal amount in the four positions of the lens's outer circle. The minimum removal amount in the four positions of the outer circle is as follows: Figure 8 , Figure 9 The shaded area is shown.

[0080] Modeling the effect of center deviation on the amount of material removed from the outer diameter in the centering edge grinding process when the optical axis intersects the geometric axis.

[0081] There are two possible scenarios for intersection:

[0082] a. The optical axis and the geometric axis intersect within the outline of the part in the front view.

[0083] b. The optical axis and the geometric axis do not intersect within the outline of the part in the front view.

[0084] In the model, centering grinding is performed with the optical axis as the rotation axis. The distance between the grinding wheel and the machine tool's rotation axis is d, and the rotation radius of the cutting is d. In the front view, translating the optical axis O1O2 symmetrically and equally by a distance d in the upper and lower directions of the outer circle yields the outer circle grinding cutting lines in the upper and lower positions. In the top view, translating the optical axis O1O2 equally by a distance d in the front and back directions of the outer circle yields the outer circle grinding cutting lines in the front and back positions. The portion between the four cutting lines and the outer circle boundary represents the removal amount in the four positions of the lens's outer circle. The minimum removal amount in the four positions of the outer circle is as follows: Figure 10 , Figure 11 The shaded area is shown.

[0085] Modeling the effect of center deviation on the amount of material removed from the outer diameter in the centering edge grinding process when the optical axis is parallel to the geometric axis.

[0086] The drawing method is the same as the intersection method. The minimum removal amount in the four directions of the outer circle is as follows: Figure 12 The shaded area is shown.

[0087] Modeling the effect of center deviation on the amount of material removed from the outer diameter in the centering edge grinding process when the optical axis coincides with the geometric axis.

[0088] The drawing method is the same as the intersection method, and the removal amount in the four directions of the outer circle is as follows: Figure 13 The shaded area is shown.

[0089] This invention provides a modeling method for analyzing the amount of material removed from the outer diameter of a spherical lens during centering edge grinding. The modeling method re-describes the center deviation under four spatial positional relationships between the optical axis and the geometric axis. These four spatial positional relationships include skewness, parallelism, intersection, and coincidence. Based on the re-description, a new spatial positional relationship between the optical axis and the geometric axis of the spherical lens is obtained. Based on this new spatial positional relationship, a model is established for the center deviation's effect on the amount of material removed from the outer diameter during centering edge grinding. In this model, centering edge grinding is performed with the optical axis as the rotation axis, and the distance between the grinding wheel and the machine tool's rotation axis is used as the cutting radius. By establishing a model according to the standardized and general process of this invention, the spatial positional relationship between the optical axis and geometric axis of various spherical lenses (biconvex, biconcave, meniscus, plano-convex, plano-concave) can be clearly obtained. The corresponding relationship between the center deviation and the grinding amount in the four directions of front, back, left, and right of the spherical lens in the centering and edge grinding process can be clearly and orderly obtained, and the outer diameter removal amount can be accurately determined. This provides theoretical support for quality problems such as the outer diameter being lower than the lower limit of the design index due to excessive outer diameter removal amount, and edge chipping entering the optical surface at the edge grinding position.

[0090] Based on the same inventive concept, this invention also provides an optical processing apparatus for spherical optical elements, wherein the processing apparatus applies the modeling method described above for analyzing the amount of material removed from the outer circle of a spherical lens during centering and edge grinding.

[0091] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention is not limited to the specific combination of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A modeling method for analyzing the amount of material removed from the outer diameter of a spherical lens during centering and edge grinding, characterized in that, The modeling method includes: The center deviation between the optical axis and the geometric axis is redescribed under four spatial positional relationships; wherein the four spatial positional relationships include skew plane, parallel, intersecting, and coincident. Based on the results of the re-description, a new spatial relationship between the optical axis and the geometric axis of the spherical lens is obtained; Based on the new spatial relationship between the optical axis and the geometric axis, a model is established for the removal amount of the outer circle in the centering edge grinding process, wherein the centering edge grinding is performed with the optical axis as the rotation axis and the distance between the grinding wheel and the rotation axis of the machine tool is the cutting rotation radius. Based on the new spatial relationship between the optical axis and the geometric axis, a model for the amount of material removed from the outer diameter of the centering edge grinding process is established, including: selecting a spherical lens of a specific shape; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are not parallel; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis intersect; drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis are parallel; and drawing a model for the amount of material removed from the outer diameter of the spherical lens in the centering edge grinding process when the optical axis and the geometric axis coincide. Based on the new spatial relationship between the optical axis and the geometric axis, a model is established for the effect of center deviation on the outer diameter removal amount in the centering grinding process, including: The relative positions of the outer circle removal amount model are established when the optical axis and the geometric axis are not parallel. In the front view of the model, the optical axis is translated symmetrically and equally by a distance d in the upper and lower directions of the outer circle to obtain the grinding cutting lines of the outer circle in the upper and lower directions. In the top view of the model, the optical axis is translated equally by a distance d in the front and back directions of the outer circle to obtain the grinding cutting lines of the outer circle in the front and back directions. The part between the four cutting lines and the outer circle boundary is the amount of material removed in the four directions of the lens outer circle, where d is the distance between the grinding wheel and the rotation axis of the machine tool. When the optical axis and geometric axis are not parallel, the placement of the outer diameter removal amount model is such that the plane parallel to the optical axis is in front and the plane parallel to the geometric axis is behind; this allows for a clear and orderly correspondence between the center deviation and the grinding amount in the four directions (front, back, top, and bottom) of the spherical lens during the centering and edge grinding process, thus accurately determining the outer diameter removal amount.

2. The modeling method according to claim 1, characterized in that, The spatial description of the center deviation when the planes are not parallel is defined as follows: the angle between the plane containing the optical axis and the plane containing the geometric axis is defined as α, where α≠0; a perpendicular line is drawn from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; a perpendicular line is drawn from the center of the sphere O1 to the plane passing through the geometric axis and the center of the sphere O2, with the foot of the perpendicular being O1″. The line segment O1O1″=C, which matches the center deviation under the traditional definition.

3. The modeling method according to claim 1, characterized in that, Spatial description of the center deviation at intersection: The optical axis and the geometric axis intersect and are coplanar. Draw a perpendicular line from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. The length of the line segment O1O1′=a1, and the length of the line segment O2O2′=a2. When the centers of the sphere O1 and O2 are located on opposite sides of the geometric axis, the center deviation C=a1+a2; when the centers of the sphere O1 and O2 are located on the same side of the geometric axis, the center deviation C=|a1-a2|.

4. The modeling method according to claim 1, characterized in that, The spatial description of the center deviation when coplanar is as follows: draw a perpendicular line from the center of the sphere O1 to the geometric axis, with the foot of the perpendicular being O1′; draw a perpendicular line from the center of the sphere O2 to the geometric axis, with the foot of the perpendicular being O2′. The lengths of the line segments are O1O1′=a1 and O2O2′=a2. The center deviation C=a1=a2≠0.

5. The modeling method according to claim 1, characterized in that, Spatial description of center deviation when the optical axis coincides with the geometric axis: center deviation C = a1 = a2 = 0.

6. The modeling method according to claim 1, characterized in that, The outer circle removal amount model satisfies the following two conditions: First, the translation distance of the optical axis in the four directions of up, down, front, and back should be equal to reflect the rotation process centered on the optical axis in the actual centering edge grinding process; Second, the outer circle should be ground in the four directions of up, down, front, and back to represent the outer circle diameter and roundness during centering edge grinding.

7. An optical processing apparatus for spherical optical elements, characterized in that, The processing device uses the modeling method for analyzing the removal amount of the outer circle of the centering edge grinding of a spherical lens as described in any one of claims 1-6.

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