Design method of eyeglass frames based on multi-point measurement data of human face

Abstract

The present invention belongs to the technical field of eyeglass design, and specifically discloses a method for designing eyeglass frames based on multi-point measurement data of human face. First, the key points of human face features are obtained, and a coordinate system is established to obtain the parameters of the eyeglass frames; then the basic graphics of the eyeglass frame style design are selected, and the basic graphics are corrected according to the parameters of the eyeglass frames to obtain the original plane frame; then the original plane frame is projected onto the surface of a sphere determined according to the myopia degree of the adapter, and the frame forward tilt angle, the total length of the temples and the bending point position are further determined; finally, a nose pad bracket is constructed to complete the design of the eyeglass frame. Based on the key points of human face features, the present invention corrects or redesigns the parameters of traditional eyeglass frames, and constructs a frame that conforms to the face of the adapter, which has excellent adaptability.

Description

Technical Field

[0001] The invention belongs to the technical field of ophthalmic medical treatment, and relates to a method for designing a spectacle frame, and in particular to a method for designing a spectacle frame based on multi-point measurement data of a human face. Background Art

[0002] At present, the eyewear industry is mostly about finished frames, and people can only choose glasses of fixed sizes, which may lead to incomplete fit. For example, the wrong length and width will lead to head clamping or vision obstruction, and the wrong nose pad position will lead to unstable wearing of glasses.

[0003] In order to solve this problem, a lot of research has been done on developing customized glasses technology. However, most of the current customized frames rely on the designer's glasses design and manual adjustment experience, which not only takes a long time to design, but also the different design methods of each designer will lead to different designed glasses, making it difficult to effectively ensure the adaptability of the glasses frame.

[0004] In order to make the customized design of glasses more streamlined, standardized and reliable, the academic and industry circles have begun to design frames based on 3D face measurement data. Although 3D scanning technology and equipment have developed rapidly, due to the incompleteness of 3D models, personalized design research is not in-depth, and the adaptability evaluation based on 3D models is not effective.

[0005] Application No. CN201610396790.9 discloses a method for designing eyeglass frames based on three-dimensional face measurement, wherein the width of the frame is automatically adjusted according to the width of the user's face; the distance from the lens to the glasses is automatically adjusted according to the user's nose height and eye socket shape; the shape of the nose pads is automatically optimized according to the user's nose shape; and the length and direction of the temples are automatically adjusted according to the position of the ears. The above-mentioned method for designing eyeglass frames based on three-dimensional face measurement first obtains a set of two-dimensional facial feature points, and then obtains the intersection of the two-dimensional facial feature point set corresponding to the depth image D and the three-dimensional grid model to obtain a set of three-dimensional facial feature points. However, the above-mentioned method for designing eyeglass frames based on three-dimensional face measurement has a very complicated design process, which is not conducive to universal application in the field of eyeglass frames; and the three-dimensional face model is very complex, and there are many key feature points, which have a key influence on the adaptability and balance of the eyeglass frames; the above-mentioned method for designing eyeglass frames is difficult to effectively reflect these key feature points, and thus it is difficult to effectively ensure the adaptability and balance of the eyeglass frames. Summary of the invention

[0006] The purpose of the present invention is to provide a glasses frame design method based on multi-point measurement data of the human face to address the above-mentioned technical problems existing in the prior art, unify the boundary conditions of customized frame design, shorten the frame design process, and improve the adaptability of the glasses frame.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions.

[0008] The inventive idea of ​​the present invention is: firstly, the key points of the facial features of the human face are obtained, and a coordinate system is established to obtain the parameters of the glasses frame; then, the basic graphics of the glasses frame style design are selected, and the basic graphics are corrected according to the parameters of the glasses frame to obtain the original plane frame; then, the original plane frame is projected onto the surface of a sphere determined according to the myopia degree of the adapter, and the forward tilt angle of the frame, the total length of the temples and the bending point position are further determined; finally, a nose pad bracket is constructed to complete the design of the glasses frame.

[0009] The present invention provides a method for designing eyeglass frames based on multi-point measurement data of human face, which comprises the following steps:

[0010] S1 obtains key points of facial features of a person, wherein the key points include symmetrically distributed nasal root points, inner canthus points, pupil points, outer canthus points, temple points, mid-brow points, zygomatic points, and ear points;

[0011] S2 takes the midpoint of the line connecting the two inner corners as the coordinate origin, the inner corner line as the X-axis, the vertical line passing through the origin and perpendicular to the inner corner line as the Y-axis, and the straight line passing through the origin and perpendicular to the plane formed by XY as the Z-axis, to obtain the coordinate value of the key feature point;

[0012] S3 calculates facial dimensions, including the distance between the root of the nose, the distance between the outer canthus of the eyes, the width of the face, the horizontal distance between the eyes and ears, and the Y-direction distance between the middle of the eyebrow and the zygomatic bone;

[0013] S4 obtains the parameters of the glasses frame:

[0014] The length of the middle bridge of the glasses frame = (0.9-1.2) × the distance from the root of the nose;

[0015] Inner width of eyeglass frame = (1.2-1.3) × distance between outer corners of eyes;

[0016] The total width of the eyeglass frame including the stud = (1.1-1.2) × face width;

[0017] Glasses frame height = (1-1.3) × Y distance between the middle of the eyebrow and the zygomatic bone;

[0018] S5 selects a basic graphic for the design of a glasses frame style, and modifies the basic graphic according to the glasses frame parameters obtained in step S4 to obtain an original plane frame, wherein the width of the pile head is determined by the total width of the glasses frame and the inner width of the glasses frame;

[0019] S6 projects the original plane frame onto the surface of a sphere determined according to the myopia of the wearer to obtain a three-dimensional frame, and determines the forward tilt angle of the frame;

[0020] S7 determines the total length of the temples of the glasses and the position of the bending points;

[0021] S8 sets the nose pad bracket based on the root of the nose to complete the design of the glasses frame.

[0022] In the above step S1, key points of facial features of a person's face are obtained by a three-dimensional facial scanner.

[0023] In the above step S3, the nasal root distance is the distance between the symmetrical nasal root points; the outer canthus distance is the distance between the symmetrical outer canthus points; the face width is the distance between the symmetrical temple points; the eye-ear horizontal distance is the horizontal distance between the projections of the pupil point and the ear point on the YZ plane; the eyebrow-zygomatic Y distance is the distance between the projections of the eyebrow midpoint and the zygomatic point on the Y axis.

[0024] In the above step S4, in a preferred implementation, the length of the middle bridge of the glasses frame = 1.1×the distance between the root of the nose; the inner width of the glasses frame = 1.2×the distance between the outer canthus of the eyes; the total width of the glasses frame including the head = 1.1×the width of the face; the height of the glasses frame = 1×the distance between the middle of the eyebrow and the zygomatic bone in the Y direction.

[0025] In the above step S5, the basic graphic of the design of the glasses frame style can be set or selected according to the needs of the user. Here, the basic graphic of the design of the glasses frame style is a plane frame set or selected according to the needs of the user. Then, the basic image is scaled according to the glasses frame parameters obtained in step S4 to obtain the original plane frame. The pile width is determined by the total width of the glasses frame and the inner width of the glasses frame; specifically, the pile width is half of the difference between the total width of the glasses frame and the inner width of the glasses frame. Then, the pile position is determined based on the style of the glasses frame, and the pile width is combined to complete the pile construction.

[0026] In the above step S6, the diameter of the sphere is determined according to the formula 52300 / myopia (in mm), and the corresponding sphere is obtained; the myopia here is the larger one of the left eye myopia and the right eye myopia. Then the geometric center of a half frame (excluding the middle beam) in the original plane frame coincides with the center of the sphere, and then the half frame is projected onto the surface of the sphere, and the length of the middle beam obtained in step S4 is used as the spacing between the half frame and the other half frame, and the other half frame is obtained by symmetrical mapping on the surface of the sphere, and the two half frames are stretched to a given thickness in the thickness direction, such as 3 to 5 mm; then, according to the selected eyeglass frame style, the middle beam is spliced ​​between the two half frames to obtain a three-dimensional frame, and the spacing between the two ends of the middle beam is the length of the middle beam. Next, the forward tilt angle of the frame is obtained according to the angle between the projection line of the midpoint of the eyebrow and the zygomatic point on the YOZ plane and the Y axis.

[0027] In the above step S7, the total length of the temple can be determined based on the total width of the frame, and the bending point of the temple can be determined based on the horizontal distance between the eyes and ears: the total length of the temple = (0.9-1.1) × the total width of the frame; the distance from the bending point to the hinged position of the temple and the stump is (0.9-1.1) × the horizontal distance between the eyes and ears; the shape of the temple (including the bending curvature of the temple ear hook structure and the vertical length section structure after the bending point) adopts conventional design.

[0028] In the above step S8, according to the position of the root of the nose, the coordinate of the Z axis remains unchanged, and along the trend of the positive coordinate of the X axis and the negative coordinate of the Y axis gradually increasing, five points are taken around the root of the nose, and then 6 points are obtained to obtain 3 spatial line segments parallel to the center beam; at the same time, based on the basic design figure of the selected eyeglass frame style or the Y-direction height of the upper edge of the pile head, the two points where the nose pad bracket is connected to the corresponding side frame are determined to obtain the fourth spatial line segment parallel to the center beam, and the four line segments are connected in a smooth transition manner to obtain a spatial curved surface, and are stretched along the thickness direction to a given thickness (for example, 3 to 5 mm) to obtain a curved nose pad bracket. A nose pad is installed on the nose pad bracket, and the nose pad installation position is 2 to 5 mm below the root of the nose on the nose pad bracket.

[0029] Set the nasion point as A, and the five points around the nasion point are A1, B, B1, C, and C1. Then A1 has the same Y and Z coordinates as A, and the X coordinate of A1 is 4.5-6.5mm larger than A; B1 has the same Y and Z coordinates as B, 1-3mm smaller than the Y coordinate of A, the X coordinate of B1 is 4.5-6.5mm larger than B, and the X coordinate of B is 0-0.5mm larger than A; C1 has the same Y and Z coordinates as C, 4-6mm smaller than the Y coordinate of B, the X coordinate of C1 is 4.5-6.5mm larger than C, and the X coordinate of C is 0-0.5mm larger than B.

[0030] Based on the Y-height of the upper edge of the pile head, moving downward by 0 to 5 mm is the Y-height of the two points where the nose pad bracket is connected to the corresponding side frame, and then the two points where the nose pad bracket is connected to the corresponding side frame are determined.

[0031] The glasses frame designed through the above steps S1-S8 can be directly obtained through 3D printing technology. A nose pad is further installed on the nose pad bracket.

[0032] Compared with the prior art, the eyeglass frame design method based on multi-point measurement data of human face provided by the present invention has the following beneficial effects:

[0033] 1. The present invention modifies or redesigns the parameters of traditional eyeglass frames based on key points of facial features (including the root of the nose, the inner canthus point, the outer canthus point, the temple point, the mid-brow point, the zygomatic point, and the ear point), and constructs a frame that fits the face of the wearer and has excellent adaptability;

[0034] 2. The present invention designs a smooth transition surface based on the points around the root of the nose to construct a nose support bracket, which can better fit the nose bridge and improve the adaptability while supporting the frame;

[0035] 3. The present invention unifies the boundary conditions of the custom design of the frames, can quickly complete the frame design, and greatly shortens the frame design process. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 The present invention is a flow chart of a method for designing eyeglass frames based on multi-point measurement data of a human face.

[0038] Figure 2 To obtain the key points of facial features of a person through a three-dimensional facial scanner.

[0039] Figure 3 Schematic diagram of a plane mirror frame.

[0040] Figure 4 Schematic diagram of the frame forward tilt angle.

[0041] Figure 5 This is a schematic diagram of the distribution of the nasion point and the five surrounding points.

[0042] Figure 6 It is a smooth transition surface generated based on the nasion point and five surrounding points.

[0043] Figure 7 Schematic diagram of the designed eyeglass frame.

[0044] Figure 8 A schematic diagram showing the fitting of eyeglass frames. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0046] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0048] Example

[0049] The present embodiment is based on the method for designing eyeglass frames based on multi-point measurement data of human face. Figure 1 As shown, it includes the following steps:

[0050] S1 obtains key points of facial features of a person, wherein the key points of the features include symmetrically distributed nasal root points, inner canthus points, pupil points, outer canthus points, temple points, mid-brow points, zygomatic points, and ear points.

[0051] In this embodiment, the key points of facial features of a person's face are obtained by a conventional three-dimensional facial scanner, such as Figure 2 As shown. The key points used in this embodiment include symmetrically distributed nasion points (47, 56), inner canthus points (17, 30), pupil points (38, 81), outer canthus points (13, 34), temple points (left eye X left: the position of the third angle of the equilateral triangle formed by the line connecting the points 34 and 43 as the side, right eye X right: the position of the third angle of the equilateral triangle formed by the line connecting the points 13 and 22 as the side), eyebrow midpoint (28, 45), zygomatic bone point (Q left: the intersection of the line extending from the midpoints of 108 and 110 to the left and right directions and 34 extending downward, Q right: the intersection of the line extending from the midpoints of 108 and 110 to the left and right directions and 13 extending downward), and ear points (0, 12).

[0052] S2 takes the midpoint of the line connecting the two inner corners as the coordinate origin, the line connecting the inner corners of the eyes as the X-axis, the vertical line passing through the origin and perpendicular to the line connecting the inner corners of the eyes as the Y-axis, and the straight line passing through the origin and perpendicular to the plane formed by XY as the Z-axis to obtain the coordinate values ​​of the feature key points.

[0053] S3 calculates facial dimensions, including the distance between the root of the nose, the distance between the outer canthus of the eyes, the width of the face, the horizontal distance between the eyes and ears, and the Y-direction distance between the middle of the eyebrow and the zygomatic bone.

[0054] like Figure 2As shown, the nasal root distance is the distance between the two nasal root points (47 and 56). The distance between the outer canthus of the eyes is the distance between (13 and 34). The face width is the distance between the two temple points (X left and X right). The eye-ear horizontal distance is the horizontal distance between the projections of the pupil point (81, 38) and the ear point (0, 12) on the YZ plane (i.e. the difference in Z coordinates). The eyebrow-zygomatic Y distance is the distance between the eyebrow center point (45, 28) and the zygomatic point (Q left, Q right) on the Y axis.

[0055] S4 obtains the parameters of the glasses frame, including the length of the middle beam of the glasses frame, the inner width of the glasses frame, the total width of the glasses frame including the pile head, and the height of the glasses frame, such as Figure 3 shown.

[0056] Get the spectacle frame parameters to meet:

[0057] The length of the middle bridge of the glasses frame = (0.9-1.2) × the distance from the root of the nose;

[0058] Inner width of eyeglass frame = (1.2-1.3) × distance between outer corners of eyes;

[0059] The total width of the eyeglass frame including the stud = (1.1-1.2) × face width;

[0060] The height of the glasses frame = (1-1.3) × the Y distance between the middle of the eyebrow and the cheekbone.

[0061] Table 1 shows the relationship between the inner width of the frame and the distance between the outer corners of the eyes for different adapters. It can be seen that the inner width of the glasses frame = (1.2-1.3) × the distance between the outer corners of the eyes.

[0062] Table 1 The inner width of the frame and the distance between the outer corners of the eyes for different adapters

[0063] Serial number Inner width(mm) Distance between outer corners of eyes (mm) Proportion Serial number Inner width(mm) Distance between outer corners of eyes (mm) Proportion 1 114 95 1.20 6 121.4 100 1.21 2 115 95 1.21 7 122.4 98 1.25 3 116 95 1.22 8 122.4 101 1.21 4 118.4 95 1.25 9 126.4 105 1.20 5 121.4 102 1.19 10 126.4 103 1.23

[0064] In this embodiment, the length of the middle beam of the glasses frame = 1.1×the distance between the root of the nose; the inner width of the glasses frame = 1.2×the distance between the outer canthus of the eyes; the total width of the glasses frame including the base = 1.1×the width of the face; the height of the glasses frame = 1×the distance between the middle of the eyebrow and the zygomatic bone in the Y direction.

[0065] S5 selects a basic graphic for designing a glasses frame style, and modifies the basic graphic according to the glasses frame parameters obtained in step S4 to obtain an original plane frame.

[0066] In this embodiment, the basic graphic of the design of the glasses frame style can be set or selected according to the needs of the adapter, and the basic graphic of the design of the glasses frame style here is a plane frame set or selected according to the needs of the adapter. Then, the basic image is scaled according to the glasses frame parameters obtained in step S4 to obtain the original plane frame. The pile head width is determined by the total width of the glasses frame and the inner width of the glasses frame; specifically, the pile head width is half of the difference between the total width of the glasses frame and the inner width of the glasses frame. Then, the pile head position is determined based on the glasses frame style, and combined with the pile head width, the pile head construction is completed.

[0067] S6 projects the original plane frame onto the surface of a sphere determined according to the myopia degree of the wearer to obtain a three-dimensional frame, and determines the forward tilt angle of the frame.

[0068] In this embodiment, the diameter of the sphere is determined according to the formula 52300 / myopia degree (in mm), and then the corresponding sphere is obtained; the myopia degree here is the larger one of the left eye myopia degree and the right eye myopia degree. Then the geometric center of a half frame in the original plane frame (excluding the center beam) is coincided with the center of the sphere, and then the half frame is projected onto the surface of the sphere, and the length of the center beam obtained in step S4 is used as the distance between the half frame and the other half frame, and the other half frame is obtained by symmetrical mapping on the surface of the sphere, and then the two half frames are stretched along the thickness direction to a given thickness, which is 3mm here; then according to the selected glasses frame style, the center beam is spliced ​​between the two half frames, and the distance between the two ends of the center beam is the length of the center beam. Next, the forward tilt angle of the frame is obtained according to the angle between the projection line of the midpoint of the eyebrow and the cheekbone point on the YOZ plane and the Y-axis, such as Figure 4 shown.

[0069] S7 determines the total length of the temples of the glasses and the position of the bending points.

[0070] The total length of the temple can be determined based on the obtained total width of the frame, and the position of the temple bending point (i.e., ear hook structure) can be determined based on the horizontal distance between the eyes and ears: total length of the temple = (0.9~1.1)×total width of the frame; the distance from the bending point to the hinged position of the temple and the stump is (0.9~1.1)×the horizontal distance between the eyes and ears; the shape of the temple (including the curvature of the temple ear hook structure and the vertical length structure after the bending point) adopts conventional design.

[0071] In this embodiment, the total length of the temples=1×the total width of the frame; the distance between the bending point and the hinged position of the temples and the stump is 1×the horizontal distance between the eyes and ears.

[0072] S8 sets the nose pad based on the root of the nose to complete the design of the glasses frame.

[0073] like Figure 5As shown, according to the position of the nasion point A, the Z-axis coordinate remains unchanged, and along the trend of the positive coordinate of the X-axis and the negative coordinate of the Y-axis gradually increasing, five points (A1, B, B1, C, C1) are taken around the nasion point, then the Y-coordinate and Z-coordinate of A1 are the same, and the X-coordinate of A1 is 5.5mm larger than that of A; the Y-coordinate and Z-coordinate of B1 are the same as those of B, which is 2mm smaller than the Y-coordinate of A, the X-coordinate of B1 is 5.5mm larger than that of B, and the X-coordinate of B is 0.5mm larger than that of A; the Y-coordinate and Z-coordinate of C1 are the same as those of C, which is 5mm smaller than the Y-coordinate of B, the X-coordinate of C1 is 5.5mm larger than that of C, and the X-coordinate of C is 0.5mm larger than that of B. In this embodiment, the coordinates of A, A1, B, B1, C, and C1 are respectively: A(x, y, z), A1(x+5.5, y, z), B(x+0.5, y-2, z), B1(x+6, y-2, z), C(x+1, y-7, z), and C1(x+6.5, y-7, z).

[0074] Based on the basic graphic design of the selected eyeglass frame style, two points (D, D1) where the nose pad bracket is connected to the corresponding side frame can be determined.

[0075] Then the eight points get four spatial line segments parallel to the center beam, and a spatial surface is obtained by connecting the four line segments in a smooth transition manner, such as Figure 6 As shown. The curved surface is stretched along its thickness direction to a given thickness (e.g., 3 to 5 mm, 3 mm in this embodiment) to obtain a curved nose pad bracket. A nose pad is installed on the nose pad bracket, and the nose pad installation position is 2 to 5 mm below the root of the nose on the nose pad bracket (5 mm in this embodiment).

[0076] The glasses frame designed through the above steps S1-S8 is as follows: Figure 7 The glasses frame can be directly obtained by 3D printing technology (such as FDM, SLA printing technology), and then the nose pad is further installed on the nose pad bracket.

[0077] The eyeglass frames designed by the method of the present invention for different wearers are then printed by 3D printing technology and further subjected to conventional chamfering and smooth polishing treatments. Figure 8 The adaptation display diagram of eyeglass frames designed for different wearers is given.

[0078] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A method for designing eyeglass frames based on multi-point measurement data of human face, characterized in that: The following steps are involved: S1. Obtaining key points of facial features of a human face, wherein the key points of the features include symmetrically distributed nasal root points, inner canthus points, pupil points, outer canthus points, temple points, mid-brow points, zygomatic bone points, and ear points; S2 Take the midpoint of the line connecting the two inner corners as the coordinate origin, the line connecting the inner corners of the eyes as the X-axis, the vertical line passing through the origin and perpendicular to the line connecting the inner corners of the eyes as the Y-axis, and the line passing through the origin and perpendicular to the plane formed by XY as the Z-axis to obtain the coordinate value of the key feature point; S3 calculates facial dimensions, including nasal root distance, distance between outer canthus, face width, horizontal distance between eyes and ears, and Y-direction distance between brow center and zygomatic bone; S4 Get the spectacle frame parameters: The length of the middle bridge of the glasses frame = (0.9~1.2) × the distance from the root of the nose; Inner width of glasses frame = (1.2~1.3) × distance between outer corners of eyes; The total width of the glasses frame including the head = (1.1~1.2) × face width; Glasses frame height = (1-1.3) × Y distance between the middle of the eyebrow and the zygomatic bone; S5: selecting a basic graphic of a glasses frame style and designing it, and modifying the basic graphic according to the glasses frame parameters obtained in step S4 to obtain an original plane frame, wherein the width of the pile head is determined by the total width of the glasses frame and the inner width of the glasses frame; S6 projects the original plane frame onto the surface of a sphere determined according to the myopia of the wearer to obtain a three-dimensional frame, and determines the forward tilt angle of the frame; S7 determines the total length of the temples of the glasses and the position of the bending points; S8 sets the nose pad bracket based on the root of the nose to complete the design of the glasses frame.

2. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 1, characterized in that: In step S3, the nasal root distance is the distance between the symmetrical nasal root points; the outer canthus distance is the distance between the symmetrical outer canthus points; the face width is the distance between the symmetrical temple points; the eye-ear horizontal distance is the horizontal distance between the projections of the pupil point and the ear point on the YZ plane; the eyebrow-zygomatic Y distance is the distance between the eyebrow midpoint and the zygomatic point on the Y axis.

3. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 1 or 2, characterized in that: In step S4, the length of the middle bridge of the glasses frame = 1.1 × the distance between the nasal roots; The inner width of the glasses frame = 1.2 × the distance between the outer corners of the eyes; the total width of the glasses frame including the pile head = 1.1 × the face width; The height of the glasses frame = 1 × the Y distance between the center of the eyebrow and the cheekbone.

4. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 1, characterized in that: In step S6, the diameter of the sphere is determined according to the formula 52300 / myopia degree, and then the corresponding sphere is obtained; then the geometric center of a half frame after removing the middle beam from the original plane frame coincides with the center of the sphere, and then the half frame is projected onto the surface of the sphere, and the length of the middle beam obtained in step S4 is used as the distance between the half frame and the other half frame, and the other half frame is obtained by symmetrical mapping on the surface of the sphere, and the two half frames are stretched to a given thickness in the thickness direction; then according to the selected eyeglass frame style, the middle beam is spliced ​​between the two half frames to obtain a three-dimensional frame, and the distance between the two ends of the middle beam is the length of the middle beam.

5. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 4, characterized in that: The forward tilt angle of the frame is obtained according to the angle between the projection line of the midpoint of the eyebrow and the zygomatic point on the YOZ plane and the Y-axis.

6. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 1, characterized in that: In step S7, the total length of the temple can be determined based on the obtained total width of the frame, and the position of the temple bending point can be determined based on the horizontal distance between the eye and the ear: the total length of the temple = (0.9~1.1) × the total width of the frame; the distance from the bending point to the hinge position of the temple and the stump is (0.9~1.1) × the horizontal distance between the eye and the ear.

7. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 1, characterized in that: In step S8, according to the position of the nasal root point, the Z-axis coordinate remains unchanged, and along the trend of gradually increasing positive coordinates of the X-axis and negative coordinates of the Y-axis, five points are taken around the nasal root point, and 3 spatial line segments parallel to the center beam are obtained from 6 points; at the same time, based on the selected basic design figure of the eyeglass frame style or the Y-direction height of the upper edge of the pile head, the two points where the nose pad bracket is connected to the corresponding side frame are determined to obtain the fourth spatial line segment parallel to the center beam, and the four line segments are connected in a smooth transition manner to obtain a spatial curved surface, which is stretched along its thickness direction to a given thickness to obtain a curved nose pad bracket.

8. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 7, characterized in that: Based on the Y-height of the upper edge of the pile head, moving downward by 0~5mm is the Y-height of the two points where the nose pad bracket is connected to the corresponding side frame, and then the two points where the nose pad bracket is connected to the corresponding side frame are determined.

9. The method for designing eyeglass frames based on multi-point measurement data of human face according to claim 7, characterized in that: The nose pad bracket is designed with a nose pad installation position, which is located on the nose pad bracket 2 to 5 mm below the root of the nose.

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