Positioning jig and processing method for glass aspheric lens

Abstract

The invention discloses a positioning jig and a processing method of a glass aspheric lens, the positioning jig comprises a jig platform, a positioning groove is arranged in the jig platform, and the positioning groove is suitable for placing the glass aspheric lens; the groove bottom of the positioning groove is provided with an injection hole, and the injection hole is suitable for injecting a liquid adhesive into a gap between the glass aspheric lens and the groove bottom surface of the positioning groove; and after being cured, the liquid adhesive is suitable for adhering and fixing the glass aspheric lens on the positioning groove. According to the design, the liquid adhesive is injected into the gap between the glass aspheric lens and the groove bottom surface of the positioning groove, the liquid adhesive completely fills the gap after being condensed and cured and has extremely high viscosity, firm bonding can be formed at the clearance of the back of the glass aspheric lens, and therefore accurate positioning of the glass aspheric lens is achieved; the precision of cutting the glass aspheric lens subsequently is improved; and the cured adhesive has no hardness, so that the adhesive does not hinder the walking engraving of a tool bit even if the adhesive is on a tool path of the engraving and milling machine.

Description

Technical Field

[0001] The present invention relates to the technical field of glass lens processing, and particularly relates to a positioning jig and processing method for glass aspherical lenses. Background Art

[0002] An aspherical lens is a lens with an aspherical symmetric curved surface shape, and its curvature may be different in different directions. The advantages of aspherical lenses compared to spherical lenses include spherical aberration correction, system miniaturization, and weight reduction. These advantages make the imaging performance and imaging quality of aspherical lenses better than those of spherical lenses.

[0003] Now, in order to pursue small size, light weight, and convenience, many lenses with aspherical lenses only intercept a part of the molded aspherical lens to achieve the optical effect. Therefore, in the manufacturing process, in addition to molding aspherical lenses that meet the dimensional requirements, it is also necessary to cut out parts with the desired local shape.

[0004] However, the aspherical surface is a free-form surface, and it is difficult to position the glass aspherical lens during the cutting process. It is easy to cause the glass aspherical lens to be displaced during the cutting process due to unreliable positioning, which affects the processing accuracy of the glass aspherical lens. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the subsequent cutting accuracy of the glass aspherical lens is low due to unreliable positioning in the prior art, and thus provide a positioning jig and processing method for glass aspherical lenses.

[0006] To solve the above technical problem, the technical solution of the present invention is as follows:

[0007] A positioning jig for a glass aspherical lens, including a jig platform, wherein a positioning groove is provided in the jig platform, and the positioning groove is adapted to place the glass aspherical lens to be cut; a plurality of injection holes are provided at the bottom of the positioning groove, and the injection holes are adapted to inject a liquid adhesive into the gap between the glass aspherical lens and the bottom surface of the positioning groove; the liquid adhesive is adapted to bond and fix the glass aspherical lens on the positioning groove after curing.

[0008] Further, the liquid adhesive is a liquid wax that shrinks in volume after curing.

[0009] Further, the liquid adhesive is liquid asphalt.

[0010] Further, the difference between the diameter of the positioning groove and the diameter of the glass aspherical lens to be cut is less than or equal to 0.005 mm; the flatness of the bottom surface of the positioning groove is less than or equal to 0.005 mm.

[0011] Further, the injection holes are strip-shaped.

[0012] Further, there are a plurality of the injection holes, and the plurality of injection holes are uniformly arranged on the bottom surface of the positioning groove.

[0013] Further, the injection holes include a plurality of first-type injection holes and a plurality of second-type injection holes. The plurality of first-type injection holes are located on the outer periphery of the bottom surface of the positioning groove, and the plurality of second-type injection holes are located in the middle of the plurality of first-type injection holes.

[0014] Further, the first-type injection holes include first-type injection hole A which are oppositely arranged and the length extension directions of both are along the first direction, and another two first-type injection hole B which are oppositely arranged and the length extension directions of both are along the second direction; the first direction is perpendicular to the second direction; there are two groups of the second-type injection holes, and each group of the second-type injection holes includes a second-type injection hole A with the length extension direction along the first direction, and two second-type injection hole B which are oppositely arranged and the length extension directions of both are along the second direction;

[0015] The first-type injection hole A and the three second-type injection holes in the same group enclose a square, and the first-type injection hole A, the second-type injection hole A and the two second-type injection holes B are respectively located on the four sides of the square.

[0016] Further, there is a first tool path extending along the first direction between two second-type injection holes A in different groups, and there is a second tool path extending along the second direction between each first-type injection hole B and the adjacent second-type injection hole B; the first tool path is vertically connected between two parallel second tool paths to form an "H"-shaped tool path.

[0017] A processing method for a glass aspherical lens includes the following steps:

[0018] S1. Place the glass aspherical lens to be cut on the positioning groove of the positioning fixture, and the positioning fixture adopts the positioning fixture for the glass aspherical lens described above;

[0019] S2. Inject a liquid adhesive into the gap between the glass aspherical lens and the bottom surface of the positioning groove through the injection holes at the bottom of the positioning groove, and the liquid adhesive will bond and fix the glass aspherical lens on the positioning groove after curing;

[0020] S3. Import the positioning fixture with the glass aspherical lens bonded and fixed into a precision engraving machine, input the shape of the part of the glass aspherical lens to be cut into the precision engraving machine, and the precision engraving machine sequentially cuts, roughly polishes and finely polishes the glass aspherical lens according to the program.

[0021] The technical solution of the present invention has the following advantages:

[0022] 1. For the positioning fixture of the glass aspherical lens provided by the present invention, by injecting a liquid adhesive into the gap between the glass aspherical lens and the bottom surface of the positioning groove, the liquid adhesive completely fills the gap after condensation and curing and has extremely strong viscosity, and can form a firm bond at the clearance area on the back of the glass aspherical lens, so as to realize the precise positioning of the glass aspherical lens, which is beneficial to improving the precision of subsequent cutting of the glass aspherical lens; moreover, the cured adhesive has no hardness, and even if the adhesive is on the tool path of the engraving machine, it does not prevent the tool head from walking and engraving.

[0023] 2. For the positioning fixture of the glass aspherical lens provided by the present invention, since the liquid wax has low viscosity and surface tension in the liquid state and forms a granular crystal structure in the solid state resulting in an increase in viscosity; after the liquid wax is injected into the gap between the glass aspherical lens and the bottom surface of the positioning groove, it can well fill the gap; when the liquid wax condenses and cures, on the one hand, it can form a firm bond at the clearance area on the back of the glass aspherical lens; on the other hand, the volume of the liquid wax will shrink after condensation and curing, so a certain negative pressure will be formed between the glass aspherical lens and the bottom surface of the positioning groove. Under the dual action of the negative pressure and the high strength viscosity of the solid wax, the glass aspherical lens can be accurately positioned in the positioning groove and is not prone to position loosening, which is beneficial to improving the precision of subsequent cutting and processing of the glass aspherical lens. In addition, the hardness of the solid wax is very low, and even if the solid wax is on the tool path of the engraving machine, it does not prevent the tool head from walking and engraving.

[0024] 3. For the positioning fixture of the glass aspherical lens provided by the present invention, since the liquid asphalt has strong viscosity after condensation, it can form a firm adhesion at the clearance area on the back of the glass aspherical lens, which is beneficial to improving the positioning accuracy; and the liquid asphalt has no hardness after curing, and even on the tool path, it does not prevent the tool head from walking and engraving.

[0025] 4. For the positioning fixture of the glass aspherical lens provided by the present invention, the difference between the diameter of the positioning groove and the diameter of the glass aspherical lens to be cut is less than or equal to 0.005 mm, and the flatness of the bottom surface of the positioning groove is less than or equal to 0.005 mm. With such settings, the glass aspherical lens is not easily loosened after being placed in the positioning groove.

[0026] 5. For the positioning fixture of the glass aspherical lens provided by the present invention, the setting of multiple injection holes can make the gap at the clearance area on the back of the glass aspherical lens be better filled with liquid wax or liquid asphalt.

[0027] 6. The positioning fixture for the glass aspherical lens provided by the present invention. Since the final shape of the glass aspherical lens after cutting is a square, an H-shaped tool path is designed at the bottom of the positioning groove to leave enough space for the tool head to move. In this way, the side of the tool head can perform fine machining on the side of the glass aspherical lens, which can not only achieve the accuracy of dimensional tolerance but also meet the requirement that the surface roughness Rq of the side of the glass aspherical lens is ≤ 1.5. In addition, this tool path design concept can be applied to various shapes of glass aspherical lenses, such as square, round, elliptical, pentagram, etc. Corresponding tool paths can be designed for programming and engraving to achieve them, and the accuracy of dimensional tolerance is very high.

[0028] 7. The processing method for the glass aspherical lens provided by the present invention. By using the above-mentioned positioning fixture for the glass aspherical lens, a glass aspherical lens product with dimensional accuracy reaching between 0.01 mm and 0.02 mm and the surface roughness of the lens side being less than 1.5 can be processed. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is a side view of the positioning fixture provided by the embodiment of the present invention;

[0031] Figure 2 It is a top view of the positioning fixture provided by the embodiment of the present invention.

[0032] Description of the reference numerals: 1, fixture platform; 2, positioning groove; 3, injection hole; 31a, first type of injection hole A; 31b, first type of injection hole B; 32a, second type of injection hole A; 32b, second type of injection hole B; 4, glass aspherical lens; 51, first tool path; 52, second tool path. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0034] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0035] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0036] As Figure 1 -2 shows a positioning fixture for a glass aspherical lens, including a fixture platform 1. A plurality of circular positioning grooves 2 are provided inside the fixture platform 1, and the positioning grooves 2 are adapted to place the glass aspherical lens 4 to be cut. A plurality of injection holes 3 are provided at the bottom of the positioning groove 2, and the injection holes 3 are adapted to inject a liquid adhesive into the gap between the glass aspherical lens 4 and the bottom surface of the positioning groove 2; the liquid adhesive is adapted to bond and fix the glass aspherical lens 4 on the positioning groove 2 after curing.

[0037] This positioning fixture for a glass aspherical lens injects a liquid adhesive into the gap between the glass aspherical lens 4 and the bottom surface of the positioning groove 2. After the liquid adhesive condenses and cures, it completely fills the gap and has extremely strong viscosity, and can form a firm bond at the clearance area on the back of the glass aspherical lens 4, thereby achieving precise positioning of the glass aspherical lens 4, which is beneficial to improving the precision of subsequent cutting of the glass aspherical lens 4; moreover, the cured adhesive has no hardness and does not prevent the tool head from walking and engraving even if the adhesive is on the tool path of the precision engraving machine.

[0038] In this embodiment, the difference between the diameter of the positioning groove 2 and the diameter of the glass aspherical lens 4 to be cut is less than or equal to 0.005 mm; the flatness of the bottom surface of the positioning groove 2 is less than or equal to 0.005 mm. With such a setting, the glass aspherical lens 4 is not likely to loosen easily after being placed in the positioning groove 2.

[0039] In some embodiments, the liquid adhesive is a liquid wax that shrinks in volume after curing. Since liquid wax has a low viscosity and surface tension in the liquid state and forms a granular crystal structure in the solid state, resulting in an increase in viscosity; after the liquid wax is injected into the gap between the glass aspherical lens 4 and the bottom surface of the positioning groove 2, it can well fill the gap; when the liquid wax condenses and solidifies, on the one hand, it can form a firm bond at the clearance area on the back of the glass aspherical lens 4; on the other hand, the volume of the liquid wax will shrink after condensation and solidification, so a certain negative pressure will be formed between the glass aspherical lens 4 and the bottom surface of the positioning groove 2. Under the dual action of the negative pressure and the high strength viscosity of the solid wax, the glass aspherical lens 4 can be accurately positioned in the positioning groove 2 and is not prone to position loosening, which is beneficial to improving the accuracy of subsequent cutting and processing of the glass aspherical lens 4. In addition, the hardness of the solid wax is very low, and even if the solid wax is on the tool path of the precision engraving machine, it does not prevent the tool head from walking and engraving. In an alternative embodiment, the liquid adhesive can also be heated liquid asphalt. Since liquid asphalt has strong viscosity after condensation, it can form a firm bond at the clearance area on the back of the glass aspherical lens 4, which is beneficial to improving the positioning accuracy. In addition, since the solid wax or solid asphalt only needs to be heated to melt, the efficiency is extremely fast. It can be sucked off with a suction pen, which is very fast and convenient, and is beneficial to improving the processing efficiency.

[0040] In this embodiment, there are multiple injection holes 3, all of which are strip-shaped, and the multiple injection holes 3 are evenly spaced on the bottom surface of the positioning groove 2, so that the gap at the clearance area on the back of the glass aspherical lens 4 can be better filled with liquid wax or liquid asphalt.

[0041] In some embodiments, the injection holes 3 include four first-type injection holes and six second-type injection holes. The four first-type injection holes are located on the outer periphery of the bottom surface of the positioning groove 2, and the six second-type injection holes are located in the middle of the multiple first-type injection holes. In fact, the shapes of the first-type injection holes and the second-type positioning holes are the same, and they are only named the first-type injection holes and the second-type positioning holes respectively for position distinction.

[0042] Further, the first-type injection holes include two first-type injection holes A31a that are oppositely arranged and whose length extension directions both extend along the first direction, and another two first-type injection holes B31b that are oppositely arranged and whose length extension directions both extend along the second direction; the first direction and the second direction are perpendicular, and in Figure 2 it, the horizontal direction is the first direction, and the vertical direction is the second direction.

[0043] There are two groups of second - type injection holes. Each group of second - type injection holes includes a second - type injection hole A32a whose length extension direction extends along the first direction, and two second - type injection holes B32b that are oppositely arranged and whose length extension directions extend along the second direction. The first - type injection hole AA31a and the three second - type injection holes in the same group enclose a square, and the first - type injection hole AA31a, the second - type injection hole A32a, and the two second - type injection holes B32b are respectively located on the four sides of the square. There is a first tool path 51 extending along the first direction between two second - type injection holes A32a in different groups, and there is a second tool path 52 extending along the second direction between each first - type injection hole B31b and the adjacent second - type injection hole B32b; the first tool path 51 is perpendicularly connected between two parallel second tool paths 52 to form an "H" - shaped tool path.

[0044] Because the final form of the glass aspherical lens 4 after cutting is a square, an "H" - shaped tool path is designed at the bottom of the positioning groove 2, which can leave enough space for the tool head to move; in this way, the side of the tool head can perform fine machining on the side of the glass aspherical lens 4, which can not only achieve the accuracy of dimensional tolerance but also meet the requirement that the surface finish Rq of the side of the glass aspherical lens 4 is ≤ 1.5. It can be understood here that this tool - path design idea can be applied to various shapes of glass aspherical lenses 4, such as square, round, elliptical, pentagram - shaped, etc. Corresponding tool paths can be designed for programming and engraving to achieve, and the accuracy of dimensional tolerance is very high.

[0045] Embodiment 2

[0046] The embodiment of the present invention provides a processing method for a glass aspherical lens, including the following steps:

[0047] Step S1: Place the glass aspherical lens 4 to be cut on the positioning groove 2 of the positioning jig. The positioning jig uses the positioning jig for the glass aspherical lens in the above - mentioned embodiment;

[0048] Step S2: Inject a liquid adhesive into the gap between the glass aspherical lens 4 and the bottom surface of the positioning groove 2 through the injection hole 3 at the bottom of the positioning groove 2. After the liquid adhesive is cured, the glass aspherical lens 4 is adhesively fixed on the positioning groove 2;

[0049] Step S3: Import the positioning jig adhesively fixed with the glass aspherical lens into a precision engraving machine, input the outline of the glass aspherical lens 4 part to be cut into the precision engraving machine, and the precision engraving machine sequentially cuts, roughly grinds, and finely grinds the glass aspherical lens 4 according to the program.

[0050] Among them, the engraving machine is an engraving machine with a tolerance that can be controlled to the micron level. The tool head used by the engraving machine is an electroplated metal tool head, and the electroplated metal tool head is divided into three models: 400#, 600#, and 800#. The 400# electroplated metal tool head is used for roughing, the 600# electroplated metal tool head is used for fine engraving, and the 800# electroplated metal tool head is used for fine surface finish repair.

[0051] For this processing method of the glass aspherical lens, by using the positioning fixture for the glass aspherical lens described above and an engraving machine with an accuracy reaching the micron level for processing, a glass aspherical lens 4 product with dimensions accurately reaching between 0.01 mm and 0.02 mm and a side roughness of the lens less than 1.5 can be processed.

[0052] Obviously, the above embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A positioning fixture for a glass aspherical lens, characterized in that It includes a fixture platform (1), within which a positioning groove (2) is provided. The positioning groove (2) is adapted to place the glass aspherical lens (4) to be cut. A number of injection holes (3) are provided at the bottom of the positioning groove (2), and the injection holes (3) are adapted to inject a liquid adhesive into the gap between the glass aspherical lens (4) and the bottom surface of the positioning groove (2). After curing, the liquid adhesive is adapted to bond and fix the glass aspherical lens (4) on the positioning groove (2).

2. The positioning fixture for the glass aspherical lens according to claim 1, characterized in that, The liquid adhesive is liquid wax.

3. The positioning jig for the glass aspherical lens according to claim 1, characterized in that, The liquid adhesive is liquid asphalt.

4. The positioning fixture for the glass aspherical lens according to claim 1, wherein, The difference between the diameter of the positioning groove (2) and the diameter of the glass aspherical lens (4) to be cut is less than or equal to 0.005 mm; the flatness of the bottom surface of the positioning groove (2) is less than or equal to 0.005 mm.

5. The positioning jig for the glass aspherical lens according to claim 1, characterized in that, The injection holes (3) are in strip shape.

6. The positioning jig for the glass aspherical lens according to claim 5, characterized in that, There are multiple injection holes (3), and the multiple injection holes (3) are evenly arranged on the bottom surface of the positioning groove (2).

7. The positioning fixture for the glass aspherical lens according to claim 5, characterized in that, The injection holes (3) include multiple first - type injection holes and multiple second - type injection holes. The multiple first - type injection holes are located on the outer periphery of the bottom surface of the positioning groove (2), and the multiple second - type injection holes are located in the middle of the multiple first - type injection holes.

8. The positioning fixture for the glass aspherical lens according to claim 7, characterized in that, The first - type injection holes include two first - type injection holes A (31a) that are oppositely arranged and whose length extension directions both extend along a first direction, and another two first - type injection holes B (31b) that are oppositely arranged and whose length extension directions both extend along a second direction; the first direction is perpendicular to the second direction. There are two groups of the second - type injection holes, and each group of the second - type injection holes includes a second - type injection hole A (32a) whose length extension direction extends along the first direction, and two second - type injection holes B (32b) that are oppositely arranged and whose length extension directions both extend along the second direction; The first - type injection hole A (31a) and the three second - type injection holes in the same group enclose a square, and the first - type injection hole A (31a), the second - type injection hole A (32a), and the two second - type injection holes B (32b) are respectively located on the four sides of the square.

9. The positioning jig for the glass aspherical lens according to claim 8, characterized in that, There is a first tool path (51) extending along the first direction between two second - type injection holes A (32a) in different groups, and there is a second tool path (52) extending along the second direction between each first - type injection hole B (31b) and the adjacent second - type injection hole B (32b); the first tool path (51) is perpendicularly connected between two parallel second tool paths (52) to form an "H" - shaped tool path.

10. A processing method for a glass aspherical lens, characterized in that It includes the following steps: S1. Place the glass aspherical lens (4) to be cut on the positioning groove (2) of the positioning fixture, and the positioning fixture adopts the positioning fixture for the glass aspherical lens according to any one of the above - mentioned claims 1 - 9; S2. Inject a liquid adhesive into the gap between the glass aspherical lens (4) and the bottom surface of the positioning groove (2) through the injection holes (3) at the bottom of the positioning groove (2), and after curing, the liquid adhesive bonds and fixes the glass aspherical lens (4) on the positioning groove (2); S3. Import the positioning jig with the glass aspherical lens adhesively fixed into the precision engraving machine, input the outline of the glass aspherical lens (4) part required to be cut into the precision engraving machine, and the precision engraving machine sequentially cuts, roughly polishes, and finely polishes the glass aspherical lens (4) according to the program.

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