An optical lens glass dispensing and bonding method

Abstract

The application discloses a kind of optical glass dispensing press bonding methods, belong to optical glass dispensing technical field.The scheme of the present application, the needle of dispensing device is vertically set upwards, and dispensing is carried out using the dispensing mode from bottom to top.Under the action of gravity, the glue attached to the optical glass forms a stalactite water drop structure due to the action of gravity, preventing the generation of bubbles during press bonding.Meanwhile, by precisely controlling the amount of glue, glue waste is reduced, and glue overflow is avoided.The scheme of the present application effectively reduces the generation of bubbles, reduces glue waste, and improves production efficiency compared to the traditional dispensing mode from top to bottom.

Description

Technical Field

[0001] This invention relates to the field of optical lens glass dispensing technology, and more particularly to a method for dispensing and pressing optical lens glass. Background Technology

[0002] Dispensing and pressing is a common optical component assembly technique, especially in the manufacture of composite lenses, touch screen modules, camera lens modules, and other optical devices. This method is typically used to bond two or more glass lenses together, ensuring the transparency and strength of the bonding interface. The basic process of dispensing and pressing includes material preparation, cleaning and drying, dispensing, alignment and pressing, and adhesive curing.

[0003] In the dispensing stage, the conventional method is to apply the adhesive vertically downwards using a needle. However, when the adhesive viscosity is low, the adhesive applied to the glass surface easily forms a crater-like depression. During the lamination process, this depression causes air bubbles to form in the adhesive, which cannot be expelled and remain in the glass laminate structure, resulting in product quality issues. To reduce bubble formation, the amount of adhesive dispensed is usually increased to compensate for this defect. However, this not only wastes adhesive but also causes excessive adhesive to overflow onto the work platform, affecting subsequent operations and reducing production efficiency. Therefore, how to reduce adhesive waste, effectively reduce bubble formation, and improve production efficiency while ensuring bonding quality has become an urgent technical problem to be solved. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for dispensing and pressing optical lens glass to address the above-mentioned deficiencies of the prior art.

[0005] To achieve the above objectives, the present invention provides a method for dispensing and pressing optical lens glass, wherein the method assembles multiple pieces of optical lens glass of the same size together by dispensing and pressing, and the method includes the following steps:

[0006] Step S1: Inject transparent optical adhesive into the dispensing tube of the dispensing device, and set the needle of the dispensing device vertically upward.

[0007] Step S2: Place the first optical lens glass flat on the work platform;

[0008] Step S3: Control the needle to apply adhesive to the second optical lens glass from below, precisely controlling the amount of adhesive applied and the vertical distance between the needle and the second optical lens glass to prevent adhesive dripping during application and overflow during pressing. During the application process, slowly increase the vertical distance between the needle and the second optical lens glass to make the adhesive application smoother. After the application is complete, move and align the second optical lens glass above the first optical lens glass. Repeat this step to complete the application and stacking of the other optical lens glasses.

[0009] Step S4: Press all the optical lens glass together as a whole and cure the transparent optical adhesive.

[0010] Preferably, step S3 specifically includes:

[0011] Step S31: Move the second optical lens glass directly above the needle tip, so that the center point of the second optical lens glass is aligned vertically with the tip of the needle tip, and the vertical distance between the needle tip and the second optical lens glass is a preset distance; the preset distance is greater than the safe distance between the needle tip and the second optical lens glass.

[0012] Step S32: Based on the size of the optical lens glass and the thickness of the adhesive layer to be formed, the required amount of adhesive is determined by a combination of calculation simulation and actual testing as the preset amount of adhesive. The preset amount of adhesive ensures that the adhesive does not drip when applied and that after pressing, it just covers the contact surface of the adjacent optical lens glass without overflowing.

[0013] Step S33: Control the needle to apply adhesive 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 adhesive dispensed reaches the preset amount.

[0014] Step S34: Move and align the second optical lens glass above the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glass in sequence.

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

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

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

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

[0020] Preferably, in step S1, the dispensing device includes a retainer for fixing the needle and adjusting the height of the needle.

[0021] Preferably, the material of the fastener 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 dispensing device is set vertically upward, and the dispensing method is adopted from bottom to top. Under the action of gravity, the glue adhering to the optical lens glass forms a stalactite-like teardrop structure, preventing air bubbles from being generated during pressing. At the same time, by precisely controlling the amount of glue, glue waste is reduced and glue overflow is avoided. Compared with the traditional top-down dispensing method, the solution of the present invention effectively reduces the generation of air bubbles, reduces glue waste, and improves production efficiency. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

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

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

[0026] Figure 3 This is a schematic diagram of the optical lens glass dispensing and pressing operation process provided in an embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The general idea of ​​this invention is to use the needle of the dispensing device to apply adhesive to the optical lens glass from bottom to top. The adhesive adhering to the optical lens glass forms a stalactite-like structure due to gravity, which prevents air bubbles from being generated during pressing. At the same time, by precisely controlling the amount of adhesive applied, adhesive waste is reduced and overflow is avoided.

[0029] The embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0030] This invention is applicable to the dispensing and lamination process of optical lens glass. The solution of this invention can reduce abnormal air bubbles and glue waste, while avoiding glue overflow and improving efficiency.

[0031] The dispensing and lamination method for optical lens glass is a common optical component assembly technique. In the dispensing stage, the conventional approach is to apply the adhesive vertically downwards using a needle. However, when the adhesive viscosity is too low, the adhesive applied to the glass surface easily forms a crater-like depression. During lamination, this depression causes air bubbles to form in the adhesive, which cannot be expelled and remain in the glass laminate structure, leading to product quality issues. To reduce bubble formation, the amount of adhesive dispensed is usually increased to compensate for this defect. More adhesive helps fill unevenness or minor defects on the contact surface, reducing air bubbles or residue, preventing depression formation, and resulting in a smoother surface. For example, using the conventional dispensing method, assuming a dispensing volume of 1 ml, the adhesive top forms a crater-like depression, causing air bubbles during lamination. Increasing the dispensing volume to 1.5 ml reduces or even eliminates the depression. While sufficient adhesive reduces the abnormality of air bubbles during lamination, excessive adhesive also leads to adhesive overflow.

[0032] like Figure 1 As shown, in order to solve the above-mentioned technical problems, this embodiment of the invention provides a method for dispensing and pressing optical lens glass. The method assembles multiple pieces of optical lens glass of the same size together by dispensing and pressing. The method includes the following steps:

[0033] Step S1: Inject transparent optical adhesive into the dispensing tube of the dispensing device, and set the needle of the dispensing device vertically upward.

[0034] like Figure 2 The diagram shown is a schematic representation of a dispensing device provided in an embodiment of the present invention. The dispensing device includes a fixture, a dispensing cylinder, a needle, an air tube, a control valve, and a controller.

[0035] The retainer is used to fix the needle and adjust its height. The dispensing cartridge is used to store adhesive. The needle is connected to one end of the dispensing cartridge, and the other end of the dispensing cartridge is connected to the control valve via the air tube. The control valve is connected to the controller, which controls the amount of adhesive dispensed and the dispensing time by controlling the opening and closing of the control valve. Air pressure ensures smooth dispensing of adhesive from the needle. Because the adhesive is sprayed onto the surface of the optical lens from below, the adhesive forms a stalactite-like teardrop structure on the surface of the optical lens due to gravity.

[0036] In this embodiment of the invention, the fixing device is made of aluminum alloy. Aluminum alloy has the advantages of high compressive strength, durability, light weight, corrosion resistance, and friction resistance. It can withstand the pressure of dispensing adhesive countless times without deformation, thus improving the dispensing accuracy. The fixing device has a nut torque, which can automatically adjust the dispensing direction and dispensing angle.

[0037] In some other embodiments of the present invention, the fixing device is made of stainless steel.

[0038] In this embodiment of the invention, the needle is a high-precision needle made of stainless steel. Stainless steel needles offer good airtightness, reducing the probability of air bubble formation, and are rust-free and corrosion-resistant. Furthermore, the adhesive itself does not corrode the needle. In some embodiments of the invention, the optical adhesive is a UV optical adhesive, which features fast curing speed, strong adhesion, and good weather resistance, and is widely used in various bonding and repair applications. The metal needle effectively prevents the adhesive from being exposed to direct light during use, avoiding accelerated curing of the UV optical adhesive by light, thus ensuring the long-term performance and dispensing accuracy of the adhesive.

[0039] To ensure the effectiveness of UV optical adhesives, proper storage and usage are crucial. UV optical adhesives should be kept away from direct sunlight during storage, as ultraviolet rays accelerate curing. The dispensing container used for storing the adhesive should be UV-protected to prevent changes in the adhesive's properties, which could affect its lifespan, the final optical effect of the product, and the accuracy of dispensing.

[0040] Step S2: Place the first optical lens glass flat on the work platform.

[0041] In some embodiments of the present invention, the working platform serves as both a pressing platform and a curing platform. In some embodiments of the present invention, the transparent optical adhesive is a UV optical adhesive, and the working platform is made of a transparent material. In other embodiments of the present invention, the transparent optical adhesive is a transparent hot melt adhesive, thermosetting adhesive, or moisture-curing adhesive, and the working platform is a heating platform.

[0042] Step S3: Control the needle to apply adhesive to the second optical lens glass from below, precisely controlling the amount of adhesive applied and the vertical distance between the needle and the second optical lens glass to prevent adhesive dripping during application and overflow during pressing. During the application process, slowly increase the vertical distance between the needle and the second optical lens glass to make the adhesive application smoother. After the application is complete, move and align the second optical lens glass above the first optical lens glass. Repeat this step to complete the application and stacking of the other optical lens glasses.

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

[0044] Step S31: Move the second optical lens glass directly above the needle tip, so that the center point of the second optical lens glass is aligned vertically with the tip of the needle tip, and the vertical distance between the needle tip and the second optical lens glass is a preset distance; the preset distance is greater than the safe distance between the needle tip 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 poor product appearance. Therefore, during the dispensing process, the needle and the optical lens glass need to maintain a certain safe distance. In some embodiments of the present invention, the height of the optical lens glass surface 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, which is generally 10-15 μm, and the preset distance is 20 μm.

[0046] Step S32: Based on the size of the optical lens glass and the thickness of the adhesive layer to be formed, the required amount of adhesive is determined by a combination of calculation simulation and actual testing as the preset amount of adhesive. The preset amount of adhesive ensures that the adhesive does not drip when applied and that after pressing, it just covers the contact surface of the adjacent optical lens glass without any overflow.

[0047] After the glue is sprayed from the needle, it adheres to the lower surface of the optical lens glass. The glue is sticky and there is an adhesive force between the glue and the glass. The glue itself also has surface tension. When the amount of glue is small, the sum of the adhesive force and the surface tension is greater than the gravity, so the glue does not easily drip.

[0048] Whether adhesive overflow occurs after lamination needs to be determined through subsequent lamination steps. Therefore, the preset adhesive amount needs to be repeatedly adjusted through experiments until it does not drip during dispensing, does not overflow during lamination, and the formed adhesive layer meets the expected design. In this embodiment of the invention, the dimensions of the optical lens glass are 20mm x 20mm and 100mm x 100mm, and the thickness of the adhesive layer is less than 2µm.

[0049] When applying adhesive from top to bottom, a larger amount of adhesive is needed to prevent pitting. During lamination, excessive adhesive can overflow onto the work platform, contaminating the work environment for the next operation. However, in this embodiment of the invention, the bottom-up dispensing method fundamentally solves the problem of air bubbles caused by crater-shaped pits. Furthermore, through repeated experiments, the dispensing amount is controlled to an appropriate value, preventing adhesive overflow during lamination, eliminating the need for repeated cleaning of the work platform, and improving the efficiency of continuous operation.

[0050] Step S33: Control the needle to apply adhesive 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 adhesive dispensed reaches the preset amount.

[0051] In this embodiment of the 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: the glue sprayed from the needle does not drip before the glue amount reaches the preset glue amount.

[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 as follows: the second optical lens glass is lifted vertically upward at the preset speed. Specifically, a robotic arm grasps the second optical lens glass, applies adhesive to it, and slowly lifts the second optical lens glass upward. Taking a preset adhesive amount of 1 ml as an example, assuming the initial distance between the needle and the second optical lens glass is 20 μm, the 1 ml adhesive amount needs to be divided into 40 sprays with a spray cycle of 1 second. During the adhesive application process, the second optical lens glass is lifted upward at a speed of 1 μm / s. When the adhesive application is completed, the second optical lens glass has been lifted upward by 40 μm, at which point the vertical distance between the needle and the second optical lens glass is 60 μm. Slowly increasing the vertical distance between the needle and the second optical lens glass is because as the amount of adhesive on the second optical lens glass increases, the pressure required for adhesive dispensing increases. Increasing the distance reduces the pressure required for adhesive dispensing, making the dispensing smoother.

[0053] In other embodiments of the present invention, the method of slowly increasing the vertical distance between the needle tip and the second optical lens glass at a preset speed is as follows: the needle tip is lowered vertically downward at the preset speed. Specifically, the height of the fixation device is adjusted by a robotic arm or other device to indirectly lower the needle tip.

[0054] Step S34: Move and align the second optical lens glass above the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glass in sequence.

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

[0056] In this embodiment of the invention, each layer of optical lens glass that makes up the optical lens glass product is sequentially glued (except for the first optical lens glass) according to the design drawings, and then aligned and placed together to prepare for subsequent pressing.

[0057] Step S4: Press all the optical lens glass together as a whole and cure the transparent optical adhesive.

[0058] This invention does not impose any particular limitation on the specific pressing method. In some embodiments of this invention, a vacuum press is used for pressing. Because the embodiments of this invention employ a bottom-applied adhesive method, the adhesive forms a stalactite-like teardrop structure in the center of the optical lens glass surface, making it less prone to air bubbles during pressing. This reduces the amount of adhesive used to compensate for pits when applying adhesive from above. Furthermore, by controlling the amount of adhesive, there is no adhesive overflow during pressing, eliminating the need to clean the work platform and improving production efficiency.

[0059] like Figure 3 The diagram shown is a schematic representation of the operation flow of a specific embodiment of the present invention. Figure 3 Using two optical lens glass pieces as an example, the process of dispensing, pressing, and curing is demonstrated. For simplicity, the first optical lens glass is referred to as the "lower glass," and the second optical lens glass as the "upper glass." The specific operation process is as follows:

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

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

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

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

[0064] (5) Pressure holding operation.

[0065] (6) Turn on the UV lamp below the platform to cure the UV optical adhesive.

[0066] In this invention, the dispensing device has its needle positioned vertically upwards, employing a bottom-up dispensing method. Under the influence of gravity, the adhesive adhering to the optical lens glass forms a stalactite-like teardrop structure, preventing air bubbles from forming during pressing. Simultaneously, precise control of the adhesive amount reduces adhesive waste and avoids overflow. Compared to traditional top-down dispensing methods, this invention effectively reduces air bubble formation, adhesive waste, and improves product yield and production efficiency. Furthermore, during the dispensing process, gradually increasing the vertical distance between the needle and the optical lens glass reduces the dispensing pressure, resulting in smoother dispensing.

[0067] The above are merely specific embodiments of the present invention and should not be construed as limiting the scope of the present invention. Equivalent variations made by those skilled in the art based on this invention, as well as changes well-known to those skilled in the art, should still fall within the scope of the present invention.

Claims

1. A method for dispensing and laminating optical lens glass, characterized in that, The method assembles multiple optical lens glass pieces of the same size together by dispensing and pressing. The method includes the following steps: Step S1: Inject transparent optical adhesive into the dispensing tube of the dispensing device, and set the needle of the dispensing device vertically upward. Step S2: Place the first optical lens glass flat on the work platform; Step S3: Control the needle to perform non-contact dispensing of adhesive onto the lower surface of the second optical lens glass from below, precisely controlling the amount of adhesive dispensed and the vertical distance between the needle and the lower surface of the second optical lens glass to prevent adhesive dripping during dispensing and overflow during pressing. During the dispensing process, as the amount of adhesive on the second optical lens glass increases and the required dispensing pressure increases, the vertical distance between the needle and the lower surface of the second optical lens glass is slowly increased at a preset speed to reduce the required dispensing pressure and make the dispensing smoother. After dispensing is completed, move and align the second optical lens glass and place it on top of the first optical lens glass. Repeat this step to complete the dispensing and stacking of other optical lens glasses in sequence. Step S4: Press all the optical lens glass together as a whole and cure the transparent optical adhesive. Step S3 specifically includes: Step S31: Move the second optical lens glass directly above the needle tip, aligning the center point of the lower surface of the second optical lens glass with the tip of the needle tip vertically, and ensuring that the vertical distance between the needle tip and the lower surface of the second optical lens glass is a preset distance; the preset distance is greater than the safety distance between the needle tip and the lower surface of the second optical lens glass; the safety distance is 10-15 μm. Step S32: Based on the size of the optical lens glass and the thickness of the adhesive layer to be formed, the required amount of adhesive is determined by a combination of calculation simulation and actual testing as the preset amount of adhesive. The preset amount of adhesive ensures that after the adhesive is sprayed from the needle, it adheres to the lower surface of the glass, forms a stalactite-like droplet-shaped hanging structure under the action of gravity without dripping, and after pressing, it just covers the contact surface of the adjacent optical lens glass without producing excess adhesive. Step S33: Control the needle to apply adhesive to the second optical lens glass. During the dispensing process, the second optical lens glass is vertically lifted upward at a speed of 1μm / s to 10μm / s to increase the vertical distance between the needle and the second optical lens glass until the amount of adhesive dispensed reaches the preset amount of adhesive. Step S34: Move and align the second optical lens glass above the first optical lens glass; refer to this step to complete the dispensing and stacking of other optical lens glass in sequence.

2. The optical lens glass dispensing and lamination method according to claim 1, characterized in that, The preset distance is 20μm; the preset speed is obtained through experimental testing, and the preset speed setting needs to meet the following conditions: the glue sprayed from the needle does not drip before the glue amount reaches the preset glue amount.

3. The optical lens glass dispensing and lamination method according to claim 1, characterized in that, The transparent optical adhesive is a UV optical adhesive, and the working platform is made of transparent material.

4. The optical lens glass dispensing and lamination method according to claim 1, characterized in that, The transparent optical adhesive is a transparent hot melt adhesive, thermosetting adhesive, or moisture-curing adhesive, and the working platform is a heating platform.

5. The optical lens glass dispensing and lamination method according to claim 1, characterized in that, In step S1, the dispensing device includes a retainer, which is used to fix the needle and adjust the height of the needle.

6. The optical lens glass dispensing and lamination method according to claim 5, characterized in that, The materials of the fastener include aluminum alloy and stainless steel.

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