Optical lens glass dispensing and pressing method

Abstract

The invention discloses an optical lens glass dispensing and pressing method, and belongs to the technical field of optical lens glass dispensing. According to the scheme, the needle head of the glue dispensing device is vertically arranged upwards, glue dispensing is conducted in a bottom-to-top glue dispensing mode, under the action of gravity, glue attached to optical lens glass forms a stalactite water-drop-shaped structure due to the action of gravity, bubbles are prevented from being generated during pressing, meanwhile, the glue amount is accurately controlled, glue waste is reduced, and glue overflowing is avoided. Compared with a traditional glue dispensing mode from top to bottom, the scheme has the advantages that bubbles are effectively reduced, glue waste is reduced, and production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical lens glass glue dispensing, and in particular to an optical lens glass glue dispensing and pressing method. Background Art

[0002] The glue dispensing and lamination method of optical lens glass is a commonly used optical component assembly technology, especially when making optical devices such as composite lenses, touch screen modules, camera lens modules, etc. This method is usually used to bond two or more glass lenses together to ensure the transparency and firmness of the bonding interface. The basic process of glue dispensing and lamination includes material preparation, cleaning and drying, glue dispensing, alignment and lamination, and glue curing.

[0003] During the glue dispensing stage, the conventional practice is to use a needle to dispense glue vertically downward. However, when the viscosity of the glue is low, the glue dispensed on the glass surface is very likely to form a pit similar to the shape of a crater. During the lamination process, this pit will cause bubbles to form in the middle of the glue, and these bubbles cannot be discharged smoothly, and eventually remain in the glass laminated structure, causing product quality problems. In order to reduce the generation of bubbles, it is usually necessary to increase the amount of glue dispensed to compensate for this defect, but this will not only cause a waste of glue, but also excessive glue dispensed may cause the glue to overflow onto the work platform, affecting subsequent operations and thus reducing production efficiency. Therefore, how to reduce glue waste, effectively reduce the generation of bubbles and improve production efficiency while ensuring the bonding quality has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in view of the above-mentioned defects of the prior art, a method for dispensing and pressing optical lens glass is provided.

[0005] To achieve the above object, the present invention provides a method for dispensing and pressing optical lens glass, wherein a plurality of optical lens glasses of the same size are assembled together by dispensing and pressing, and the method comprises the following steps:

[0006] Step S1, injecting transparent optical glue into a dispensing cylinder of a dispensing device so that the needle of the dispensing device is arranged vertically upward;

[0007] Step S2, placing the first optical lens glass flat on a working platform;

[0008] Step S3, control the needle to dispense glue to the second optical lens glass from below the second optical lens glass, accurately control the amount of glue dispensed and the vertical distance between the needle and the second optical lens glass, to avoid glue dripping during dispensing and glue overflow during pressing; during the dispensing process, slowly increase the vertical distance between the needle and the second optical lens glass to make the glue discharge smoother; after the dispensing is completed, move the second optical lens glass and align it to be placed above the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence;

[0009] Step S4, pressing all the optical lens glasses together as a whole, and curing the transparent optical glue.

[0010] Preferably, the step S3 specifically includes:

[0011] Step S31, moving the second optical lens glass to just above the needle head, so that the center point of the second optical lens glass is aligned with the top of the needle head in the vertical direction, and the vertical distance between the needle head and the second optical lens glass is a preset distance; the preset distance is greater than the safety distance between the needle head and the second optical lens glass;

[0012] Step S32, according to the size of the optical lens glass and the thickness of the glue layer to be formed, the required glue dispensing amount is obtained by combining calculation simulation with actual testing as a preset glue dispensing amount; the preset glue dispensing amount is such that the glue does not drip during dispensing, and after pressing, the contact surface of the adjacent optical lens glass is just covered without overflowing glue;

[0013] Step S33, controlling the needle to dispense glue to the second optical lens glass, and during the dispensing process, slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed until the amount of glue dispensed reaches a preset amount of glue dispensed;

[0014] Step S34, move and align the second optical lens glass to be placed on top of the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence.

[0015] Preferably, in step S33, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: lifting the second optical lens glass vertically upward at the preset speed.

[0016] Preferably, in step S33, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: vertically lowering the needle at the preset speed.

[0017] Preferably, the safety distance is 10 to 15um, the preset distance is 20um; the preset speed is 1um / s to 10um / s, and the preset speed is obtained through experimental tests. The setting of the preset speed needs to meet the following conditions: before the dispensing amount reaches the preset dispensing amount, the glue sprayed from the needle does not drip.

[0018] Preferably, the transparent optical glue is UV optical glue, and the working platform is made of transparent material.

[0019] Preferably, the transparent optical glue is a transparent hot melt glue, a thermosetting glue or a moisture curing glue, and the working platform is a heating platform.

[0020] Preferably, in step S1, the dispensing device includes a fixture, and the fixture is used to fix the needle and adjust the height of the needle.

[0021] Preferably, the material of the fixer includes aluminum alloy and stainless steel.

[0022] The present invention has the following beneficial effects: In the solution of the present invention, the needle of the glue dispensing device is arranged vertically upward, and the glue dispensing is performed in a bottom-up glue dispensing method. Under the action of gravity, the glue attached to the optical lens glass forms a stalactite droplet-shaped structure due to the action of gravity, thereby preventing bubbles from being generated during pressing, and at the same time, the glue waste is reduced and glue overflow is avoided by accurately controlling the glue amount. Compared with the traditional top-down glue dispensing method, the solution of the present invention effectively reduces the generation of bubbles, reduces glue waste, and improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 A schematic diagram of the steps of a method for dispensing and pressing optical lens glass provided in an embodiment of the present invention.

[0025] Figure 2 A schematic diagram of a dispensing device provided in an embodiment of the present invention.

[0026] Figure 3 A schematic diagram of the process flow of dispensing and pressing the optical lens glass provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The general idea of ​​the present invention is to use the needle of the dispensing equipment to dispense glue on the optical lens glass from bottom to top. The glue attached to the optical lens glass forms a stalactite droplet-shaped structure due to gravity, which prevents the generation of bubbles during pressing. At the same time, the glue waste is reduced and glue overflow is avoided by accurately controlling the amount of glue dispensed.

[0029] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings of the specification. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0030] The present invention is applicable to the glue dispensing and pressing process of optical lens glass. The scheme of the present invention can reduce abnormal bubbles and glue waste, avoid glue overflow and improve efficiency.

[0031] The dispensing and pressing method of optical lens glass is a commonly used optical component assembly technology. In the dispensing stage, the conventional practice is usually to use the method of dispensing glue vertically downward with a needle. However, when the viscosity of the glue is too low, the glue applied to the glass surface is very likely to form a pit similar to the shape of a crater. During the pressing process, this pit will cause bubbles to form in the middle of the glue, and these bubbles cannot be discharged smoothly, and eventually remain in the glass laminated structure, causing product quality problems. In order to reduce the generation of bubbles, it is usually necessary to increase the amount of glue dispensed to compensate for this defect. More glue helps to fill the unevenness or tiny defects on the contact surface, reduce bubbles or air residue, avoid the formation of pits, and thus form a smoother surface. For example, according to the previous method of dispensing, assuming that the amount of glue dispensed is 1 ml, there is a pit similar to the shape of a crater on the top of the glue, and bubbles are generated during lamination. When the amount of glue dispensed is increased to 1.5 ml, the pit becomes smaller or even disappears. When the amount of glue is sufficient, the pressing action is performed to reduce the abnormality of bubbles, but because the amount of glue dispensed is too much, the problem of overflow glue is generated.

[0032] like Figure 1 As shown, in order to solve the above technical problems, an embodiment of the present invention provides a method for dispensing and pressing optical lens glass, wherein a plurality of optical lens glasses of the same size are assembled together by dispensing and pressing, and the method comprises the following steps:

[0033] Step S1, injecting transparent optical glue into a dispensing cylinder of a dispensing device, so that the needle of the dispensing device is arranged vertically upward.

[0034] like Figure 2 The figure shows a schematic diagram of a glue dispensing device provided by an embodiment of the present invention. The glue dispensing device comprises a fixer, a glue dispensing cylinder, a needle, an air pipe, a control valve, and a controller.

[0035] The holder is used to fix the needle and adjust the height of the needle. The dispensing cylinder is used to store glue, the needle is connected to one end of the dispensing cylinder, the other end of the dispensing cylinder is connected to the control valve through the air pipe, the control valve is connected to the controller, and the controller can control the amount of glue and the duration of glue dispensing by controlling the opening and closing of the control valve, and the needle is ensured to discharge glue smoothly through air pressure, because the glue is sprayed from the bottom to the glass surface of the optical lens, and the glue presents a stalactite droplet-shaped structure on the glass surface of the optical lens due to gravity.

[0036] In the embodiment of the present invention, the material of the fixture is aluminum alloy, which has the advantages of high compressive strength, durability, light weight, corrosion resistance, and friction resistance. It can withstand numerous high-intensity pressures during dispensing without deformation, thereby improving the dispensing accuracy. The fixture has a nut torque that can automatically adjust the dispensing direction and angle.

[0037] In some other embodiments of the present invention, the material of the fixator is stainless steel.

[0038] In an embodiment of the present invention, the needle is a high-precision needle made of stainless steel. The stainless steel needle has good air tightness, can reduce the probability of bubble generation, has the characteristics of being rust-proof and corrosion-resistant, and the glue itself will not corrode the needle. In addition, in some embodiments of the present invention, the optical glue is UV optical glue, which has the characteristics of fast curing speed, strong adhesion, good weather resistance, etc., and is widely used in various bonding and repairing occasions. The metal needle can effectively ensure that the glue will not be directly exposed to light during use, avoid UV optical glue from encountering light to accelerate curing, and ensure the long-term performance of the glue and the accuracy of dispensing.

[0039] In order to ensure the effectiveness of UV optical glue, reasonable storage and use methods are essential. UV optical glue should be stored away from direct sunlight, because ultraviolet rays will accelerate the curing of the glue. The dispensing tube for storing the glue should be treated with UV protection to prevent the characteristics of the UV optical glue from changing, thus affecting the service life of the UV optical glue and the final optical effect of the product and the accuracy of dispensing.

[0040] Step S2, placing the first optical lens glass flat on a working platform.

[0041] In an embodiment of the present invention, the working platform is used as a pressing platform and also as a curing platform. In some embodiments of the present invention, the transparent optical glue is UV optical glue, and the working platform is made of a transparent material. In other embodiments of the present invention, the transparent optical glue is a transparent hot melt glue, a thermosetting glue, or a moisture curing glue, and the working platform is a heating platform.

[0042] Step S3, control the needle to dispense glue to the second optical lens glass from the bottom of the second optical lens glass, accurately control the amount of glue dispensed and the vertical distance between the needle and the second optical lens glass, to avoid glue dripping during dispensing and glue overflow during pressing; during the dispensing process, slowly increase the vertical distance between the needle and the second optical lens glass to make the glue discharge smoother; after the dispensing is completed, move the second optical lens glass and align it to the top of the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence.

[0043] In the embodiment of the present invention, step S3 specifically includes:

[0044] Step S31, move the second optical lens glass to directly above the needle head, so that the center point of the second optical lens glass is vertically aligned with the top of the needle head, and the vertical distance between the needle head and the second optical lens glass is a preset distance; the preset distance is greater than the safety distance between the needle head and the second optical lens glass.

[0045] If the needle is too close to the surface of the optical lens glass, it is easy to scratch it, resulting in a poor product appearance. Therefore, during the dispensing process, the needle and the optical lens glass need to maintain a certain safety distance. In some embodiments of the present invention, the height of the surface of the optical lens glass product is determined by an infrared rangefinder, and the height of the needle tip is confirmed by a gravity contact meter. Based on these two parameters, the vertical distance between the needle and the optical lens glass is ensured to be a safe distance. The safety distance is generally 10 to 15um, and the preset distance is 20um.

[0046] Step S32, according to the size of the optical lens glass and the thickness of the glue layer to be formed, the required glue dispensing amount is obtained as the preset glue dispensing amount by combining calculation simulation with actual testing; the preset glue dispensing amount ensures that the glue does not drip during dispensing, and after pressing, it just covers the contact surface of the adjacent optical lens glass without overflowing glue.

[0047] After the glue is sprayed out from the needle, it is adsorbed on the lower surface of the optical lens glass. The glue is sticky, there is adhesion between the glue and the glass, and the glue itself also has surface tension. When the amount of glue is not large, the sum of the adhesion and surface tension is greater than gravity, and the glue is not easy to drip.

[0048] Whether glue overflow occurs after lamination can only be determined through the subsequent lamination steps. Therefore, the preset glue dispensing amount needs to be adjusted repeatedly through experiments until there is no dripping during dispensing, no glue overflow during lamination, and the formed glue layer meets the expected design. In the embodiment of the present invention, the size of the optical lens glass is 20mmx20mm and 100mmx100mm, and the thickness of the glue layer is less than 2um.

[0049] When dispensing glue from top to bottom, in order to prevent pits, the amount of glue dispensed needs to be increased. During lamination, excessive amount of glue dispensed will cause glue to overflow onto the work platform, polluting the next working environment. In the embodiment of the present invention, the problem of bubbles caused by pits similar to the shape of craters is fundamentally solved by dispensing glue from bottom to top; and through repeated experiments, the amount of glue dispensed is controlled at an appropriate value, so that there is no glue overflow during lamination, and there is no need to repeatedly clean the work platform, thereby improving the efficiency of continuous operation.

[0050] Step S33, controlling the needle to dispense glue to the second optical lens glass. During the dispensing process, slowly increase the vertical distance between the needle and the second optical lens glass at a preset speed until the amount of glue dispensed reaches a preset amount.

[0051] In an embodiment of the present invention, the preset speed is 1um / s to 10um / s. The preset speed is obtained through experimental testing. The setting of the preset speed needs to meet the following conditions: before the dispensing amount reaches the preset dispensing amount, the glue sprayed from the needle does not drip.

[0052] In some embodiments of the present invention, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: lifting the second optical lens glass vertically upward at the preset speed. Specifically, the second optical lens glass is grasped by a manipulator, the second optical lens glass is dispensed, and the second optical lens glass is slowly lifted upward. Taking the preset dispensing amount of 1ml as an example, assuming that the initial distance between the needle and the second optical lens glass is 20um, the dispensing amount of 1ml needs to be divided into 40 injections, and the injection cycle is 1 second. During the dispensing process, the second optical lens glass is lifted upward at a speed of 1um / s. When the dispensing is completed, the second optical lens glass is lifted up by 40um. At this time, the vertical distance between the needle and the second optical lens glass is 60um. The vertical distance between the needle and the second optical lens glass is slowly increased because as the amount of glue on the second optical lens glass increases, the pressure required for dispensing becomes greater and greater. Increasing the distance can reduce the pressure required for dispensing and make dispensing smoother.

[0053] In some other embodiments of the present invention, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: vertically lowering the needle at the preset speed. Specifically, the height of the fixture is adjusted by a manipulator or other device to indirectly lower the needle.

[0054] Step S34, move and align the second optical lens glass to be placed on top of the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence.

[0055] In some embodiments of the present invention, after dispensing is completed, the optical lens glass is slowly lifted upward until the vertical distance between the optical lens glass and the needle is greater than 1 mm, and then the optical lens glass is transferred to the working platform.

[0056] In the embodiment of the present invention, the layers of optical lens glass constituting the optical lens glass product are glued in sequence (except the first optical lens glass) according to the design drawings, and then aligned and placed together to prepare for subsequent pressing.

[0057] Step S4, pressing all the optical lens glasses together as a whole, and curing the transparent optical glue.

[0058] The present invention has no special restrictions on the specific lamination method. In some embodiments of the present invention, a vacuum laminating machine is used for lamination. Because the embodiments of the present invention adopt the method of dispensing glue from below, the glue forms a stalactite droplet-shaped structure in the center of the glass surface of the optical lens, and bubbles are not easily generated during lamination. The amount of glue used to fill the pits by dispensing glue from above can be reduced. At the same time, by controlling the amount of glue, there is no glue overflow during lamination, and there is no need to clean the work platform, thereby improving production efficiency.

[0059] like Figure 3 FIG. 1 is a schematic diagram of an operation flow of a specific embodiment of the present invention. Figure 3 Taking two optical lens glasses as an example, the operation process of dispensing, pressing and curing is demonstrated. For the sake of simplicity, the first optical lens glass is called "lower glass" and the second optical lens glass is called "upper glass". The specific operation process is as follows:

[0060] (1) The robot grabs the upper glass.

[0061] (2) Move the center of the upper glass to a height of 20 μm above the needle, and apply UV optical glue to the lower surface of the upper glass. During the glue dispensing process, the robot slowly moves the upper glass vertically upward at a speed of 1 μm / s. When the glue dispensing is completed, the vertical distance between the upper glass and the needle is 60 μm.

[0062] (3) After dispensing is completed, the robot moves the upper glass upward until the vertical distance between the upper glass and the needle is greater than 1 mm.

[0063] (4) The robot grabs the upper glass and places it above the lower glass on the lower platform, slowly descends, aligns the two pieces of glass, and then presses them together. The lower platform is made of transparent material.

[0064] (5) Pressure maintenance operation.

[0065] (6) Turn on the UV lamp under the lower platform to cure the UV optical glue.

[0066] In the solution of the present invention, the needle of the glue dispensing device is arranged vertically upward, and the glue dispensing is performed in a bottom-up glue dispensing method. Under the action of gravity, the glue attached to the optical lens glass forms a stalactite droplet-shaped structure due to the action of gravity, thereby preventing the generation of bubbles during pressing. At the same time, the glue amount is precisely controlled to reduce glue waste and avoid glue overflow. Compared with the traditional top-down glue dispensing method, the solution of the present invention effectively reduces the generation of bubbles, reduces glue waste, and improves product yield and production efficiency. In addition, during the glue dispensing process, the vertical distance between the needle and the optical lens glass is slowly increased, which reduces the glue discharge pressure and makes the glue discharge smoother.

[0067] The above are only specific implementations of the present invention, which cannot be used to limit the scope of the present invention. Equivalent changes made by ordinary technicians in this technical field based on this creation, as well as changes known to technicians in this field, should still fall within the scope of the present invention.

Claims

1. A method for dispensing and pressing optical lens glass, characterized in that: The method assembles a plurality of optical lens glasses of the same size together by glue dispensing and pressing, and the method comprises the following steps: Step S1, injecting transparent optical glue into a dispensing cylinder of a dispensing device so that the needle of the dispensing device is arranged vertically upward; Step S2, placing the first optical lens glass flat on a working platform; Step S3, control the needle to dispense glue to the second optical lens glass from below the second optical lens glass, accurately control the amount of glue dispensed and the vertical distance between the needle and the second optical lens glass, to avoid glue dripping during dispensing and glue overflow during pressing; during the dispensing process, slowly increase the vertical distance between the needle and the second optical lens glass to make the glue discharge smoother; after the dispensing is completed, move the second optical lens glass and align it to be placed above the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence; Step S4, pressing all the optical lens glasses together as a whole, and curing the transparent optical glue.

2. The method for dispensing and pressing optical lens glass according to claim 1, characterized in that: The step S3 specifically includes: Step S31, moving the second optical lens glass to just above the needle head, so that the center point of the second optical lens glass is aligned with the top of the needle head in the vertical direction, and the vertical distance between the needle head and the second optical lens glass is a preset distance; the preset distance is greater than the safety distance between the needle head and the second optical lens glass; Step S32, according to the size of the optical lens glass and the thickness of the glue layer to be formed, the required glue dispensing amount is obtained by combining calculation simulation with actual testing as a preset glue dispensing amount; the preset glue dispensing amount is such that the glue does not drip during dispensing, and after pressing, the contact surface of the adjacent optical lens glass is just covered without overflowing glue; Step S33, controlling the needle to dispense glue to the second optical lens glass, and during the dispensing process, slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed until the amount of glue dispensed reaches a preset amount of glue dispensed; Step S34, move and align the second optical lens glass to be placed on top of the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glasses in sequence.

3. The method for dispensing and pressing optical lens glass according to claim 2, characterized in that: In the step S33, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: lifting the second optical lens glass vertically upward at the preset speed.

4. The method for dispensing and pressing optical lens glass according to claim 2, characterized in that: In the step S33, the method of slowly increasing the vertical distance between the needle and the second optical lens glass at a preset speed is: vertically lowering the needle at the preset speed.

5. The method for dispensing and pressing optical lens glass according to claim 2, characterized in that: The safety distance is 10 to 15um, the preset distance is 20um; the preset speed is 1um / s to 10um / s, and the preset speed is obtained through experimental tests. The setting of the preset speed needs to meet the following conditions: before the dispensing amount reaches the preset dispensing amount, the glue sprayed from the needle does not drip.

6. The method for dispensing and pressing optical lens glass according to claim 1, characterized in that: The transparent optical glue is UV optical glue, and the working platform is made of transparent material.

7. The method for dispensing and pressing optical lens glass according to claim 1, characterized in that: The transparent optical glue is a transparent hot melt glue, a thermosetting glue or a moisture curing glue, and the working platform is a heating platform.

8. The method for dispensing and pressing optical lens glass according to claim 1, characterized in that: In the step S1, the dispensing device includes a fixture, and the fixture is used to fix the needle and adjust the height of the needle.

9. The method for dispensing and pressing optical lens glass according to claim 8, characterized in that: The material of the fixer includes aluminum alloy and stainless steel.

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