Glued lens processing technology capable of preventing deformation
By performing lens polishing, coating, gluing and curing processes under specific conditions, the problem of deformation of the glued lenses is solved, and high-quality gluing of the lenses and improvement of their optical performance are achieved.
Patent Information
- Application Number
- CN202510342761.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-21
- Publication Date
- 2025-09-16
AI Technical Summary
In the existing lens bonding process, lens deformation caused by different material expansion coefficients and uneven glue thickness affects the product yield and optical performance.
Lenses are polished and aperture tested under specific temperature and humidity conditions. After coating, glue is dispensed and initial curing is performed. UV lamps and an insulated box are used to eliminate internal stress, and black coating is combined to control lens deformation.
The dimensional change of the lens during the processing is reduced, the concentricity and optical performance of the lens are improved, and the quality and yield rate of the glued lens are improved.
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of laminated lenses, in particular to a process for processing laminated lenses that can prevent deformation. Background Art
[0002] Cemented lenses are typically made of two or more lenses made of different materials (one positive and one negative) bonded together with optical glue, primarily to eliminate chromatic aberration. Due to the different materials and expansion coefficients of the two lenses, as well as the different R values of the mirror surfaces required to bond the two lenses, the glue thickness is uneven. Consequently, during the bonding process, the tension generated by the uneven curing of the glue can cause deformation of the negative meniscus lens. Consequently, existing processes for bonding lenses produce low product yields. Furthermore, because the lenses being bonded have curved surfaces, light refraction on these surfaces can cause deviations in various locations on the bonded surface. During initial curing, the short curing time and uneven light exposure result in significant differences in the degree of glue curing at various locations on the bonded surface. This uneven internal stress in the glue can lead to severe lens deformation. Summary of the Invention
[0003] The purpose of the present invention is to provide a process for processing laminated lenses that prevents deformation in order to overcome the defects and shortcomings of the prior art.
[0004] To achieve the above object, the technical solution adopted by the present invention is: The present invention provides a process for processing a laminated lens to prevent deformation, comprising the following steps: (1) The lens surface is subjected to single-piece rough grinding and fine grinding in sequence, polished in an environment with a temperature of 25±2℃ and a humidity of 60%~70%, and the aperture is tested; (2) After testing, the lens is edged to the specified size; (3) Both the bonding surfaces of the two lenses are coated; (4) After positioning the negative lens, use a glue dispenser to drop glue onto the center of the concave surface of the negative lens; (5) Assemble the positive lens onto the glued negative lens and spread the glue evenly into the gap between the positive lens and the negative lens; (6) Use a UV lamp with an ultraviolet energy of 80mj or more, with a UV irradiation intensity of 10mw / cm²~20mw / cm², and irradiation for 8~200 seconds for initial curing; (7) After the initial curing, the main curing is carried out; (8) The side surface of the cured laminated lens is painted black.
[0005] Furthermore, in step (7), the UV curing is below 1 mw / cm², the energy required for UV glue curing is 4500 mj, and the irradiation time is 1.25 hours; during the curing, the ambient temperature is 25±2°C.
[0006] Furthermore, in step (7), the cured bonded lens is placed in a heat preservation box at a temperature of 35°C-45°C for a long time to eliminate internal stress, and the time is selected to be 4 hours-6 hours.
[0007] Furthermore, in step (8), the baking temperature should be lower than 80° C., and the baking time should be lower than 1.5 hours.
[0008] Furthermore, after the glue is diffused in step (5), the bonded lens is placed on a jig, and under a transmissive eccentric microscope, the physical centers of the two lenses are adjusted so that the optical axes of the two lenses coincide, and the two lenses are positioned using a tool, and then the initial curing in step (6) is performed.
[0009] Furthermore, in step (5), the glue with a viscosity of less than 300 mPa.s can be placed naturally on a horizontal workbench to wait for the glue to spread naturally due to its low viscosity; if the glue viscosity is above 300 mPa.s, the lens after dispensing glue is placed on a clean black cardboard, and the lower piece will remain motionless due to friction. A rubber rod that will not scratch the surface of the lens is used to press the upper piece and rotate it clockwise, so that the upper piece rotates spherically around the lower piece clockwise until the glue between the upper lens and the lower lens is uniform.
[0010] Furthermore, the outer diameter of the negative lens in step (2) needs to be controlled within ΦD±0.004 mm.
[0011] Furthermore, in step (4), the glue needs to be brought from the refrigerator to room temperature before dispensing.
[0012] Furthermore, the coating on the bonding surface in step (3) is a single-layer film, and the film material is either silicon dioxide or magnesium fluoride.
[0013] Furthermore, in step (7), the side of the laminated lens with high transmittance faces the UV lamp.
[0014] The beneficial effects of the present invention are: 1. During the lens bonding process, the temperature must be maintained at 25°C for polishing, gluing, initial curing, and final curing. This can reduce the dimensional changes of the lenses during the bonding process, reduce the risk of lens deformation after bonding, and improve the quality of the bonded lenses.
[0015] 2. In the present application, the power of the initial curing is further reduced than the conventional initial curing power, which prolongs the illumination time and reduces the curing speed, so that each position of the curved mirror surface can obtain sufficient illumination time, and the energy absorbed by each position of the bonding surface tends to be consistent, thereby reducing the risk of lens deformation caused by bonding of concave and convex surfaces and improving the quality of lens bonding. DETAILED DESCRIPTION
[0016] The present invention will be further described below.
[0017] The present invention provides a process for processing a laminated lens to prevent deformation, comprising the following steps: (1) The lens surface is subjected to single-piece rough grinding and fine grinding in sequence, and polished in an environment with a temperature of 25±2℃ and a humidity of 60%~70%, and then the aperture is tested; when the positive lens and the negative lens are matched; if the R value of the convex piece is small, the R value of the concave piece should also be synchronously small, and when the R value of the convex piece is large, the concave piece should also be synchronously large. Therefore, one of the lenses is processed first and a random inspection is carried out to confirm the trend of the R value deviation, and then the other lens matched with it is processed in a targeted manner according to the deviation of the R value of the lens, to ensure that the deviation of the lens processed later is consistent with that of the lens processed earlier; Aperture detection is done by manually pressing a sample onto the lens surface. Excessive pressure should be avoided to prevent reading errors. To avoid the influence of human force changes and human body temperature, a high-precision laser interferometer should be used to directly detect aperture and local deviation. (2) After testing, the lens is edged to the specified outer diameter. The outer diameter of the negative lens needs to be controlled within ΦD±0.004mm; (3) The bonding surfaces of the two lenses are coated with a single-layer film made of either silicon dioxide or magnesium fluoride; (4) After positioning the negative lens, take out the glue used for bonding from the refrigerator and place it at room temperature for about 1 hour to ensure that the glue is consistent with the ambient temperature (25±2℃). Use a glue dispenser to drop the glue onto the center of the concave surface of the negative lens. The calculation process of the glue drop amount: the two glued lenses can be assumed to be two spherical segments, and the difference in the volume of the large and small spherical segments is the volume of the glue. (5) Assemble the positive lens onto the negative lens after dispensing glue, and spread the glue evenly into the gap between the positive lens and the negative lens; glue with a viscosity of less than 300mPa.s can be placed naturally on a horizontal workbench due to its low viscosity and wait for the glue to spread naturally; if the glue viscosity is above 300mPa.s, place the lens after dispensing glue on a clean black cardboard. The lower piece will remain motionless due to friction. Use a rubber stick that will not scratch the surface of the lens to press the upper piece and rotate it clockwise, so that the upper piece rotates spherically around the lower piece clockwise until the glue between the upper and lower lenses is even; the basis for judging whether the glue is even is to observe the Newton rings displayed on the upper piece with the naked eye; (6) After the glue diffuses and before it is initially cured, place the lower lens of the bonded lens on the jig. Under a transmissive eccentric microscope, adjust the physical center of the upper lens so that the optical axes of the two lenses coincide, and use a tool to hold the upper lens to maintain the position of the two lenses. Adjust the strength of the upper lens between 1N and 2N, and the strength used to hold the upper lens is 0.1N. After the lens is positioned, use a UV lamp with an ultraviolet energy of more than 80mj, at room temperature, with a UV irradiation intensity of 10mw / cm²~20mw / cm², and irradiation for 8~200 seconds to perform initial curing. (7) After the initial curing, place the side of the laminated lens with high transmittance toward the UV lamp for the curing process. The UV light for the curing process is below 1mw / cm², and the energy required for the UV glue curing is 4500mj, and the irradiation time is 1.25 hours. During the curing process, the ambient temperature for the curing process is 25±2℃. The laminated lens after the curing process is placed in a heat preservation box at a temperature of 35℃-45℃ for a long time to eliminate the internal stress. The time is selected to be 4 hours-6 hours. (8) The side surface of the cured laminated lens is painted black. The baking temperature should be lower than 80°C and the baking time should be less than 1.5 hours.
[0018] Beneficial effects of the present invention: 1. During the lens bonding process, the temperature must be maintained at 25°C during polishing, aperture detection, dispensing, initial curing, and final curing. This can reduce the dimensional changes of the lenses during the bonding process, reduce the risk of lens deformation after bonding, and improve the quality of the bonded lenses.
[0019] 2. In this application, the power of the initial curing is further significantly reduced compared to the conventional initial curing power, which prolongs the illumination time and reduces the curing speed, so that each position of the curved mirror surface receives sufficient illumination time, and the energy absorbed by each position of the bonding surface tends to be consistent, reducing the risk of lens deformation caused by bonding concave and convex surfaces, and improving the quality of lens bonding; 3. Before the initial curing, the centering treatment is carried out in an eccentric microscope, and during the initial curing, tools are used to keep the lens centered to improve the concentricity of the glued lens after the initial curing.
[0020] 4. Before the black coating process, eliminate the internal stress of the lens to reduce the micro deformation of the lens during black coating and improve product quality.
[0021] The above description is only a preferred embodiment of the present invention. Therefore, any equivalent changes or modifications made according to the structure, characteristics and principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.
Claims
1. A process for processing laminated lenses to prevent deformation, characterized by: The steps include: (1) The lens surface is subjected to single-piece rough grinding and fine grinding in sequence, polished in an environment with a temperature of 25±2℃ and a humidity of 60%~70%, and the aperture is tested; (2) After testing, the lens is edged to the specified size; (3) Both the bonding surfaces of the two lenses are coated; (4) After positioning the negative lens, use a glue dispenser to drop glue onto the center of the concave surface of the negative lens; (5) Assemble the positive lens onto the glued negative lens and spread the glue evenly into the gap between the positive lens and the negative lens; (6) Use a UV lamp with an ultraviolet energy of 80mj or more, with a UV irradiation intensity of 10mw / cm²~20mw / cm², and irradiation for 8~200 seconds for initial curing; (7) After the initial curing, the main curing is carried out; (8) The side surface of the cured laminated lens is painted black.
2. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (7), the ultraviolet light for this curing is below 1mw / cm², the energy required for curing the ultraviolet glue is 4500mj, and the irradiation time is 1.25 hours; during this curing, the ambient temperature for curing is 25±2℃.
3. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: Step (7) After curing, the bonded lens is placed in a heat preservation box at a temperature of 35°C-45°C for a long time to eliminate internal stress, and the time is selected to be 4 hours-6 hours.
4. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (8), the baking temperature should be lower than 80°C and the baking time should be lower than 1.5 hours.
5. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: After the glue has spread in step (5), the bonded lenses are placed on a jig. Under a transmissive eccentric microscope, the physical centers of the two lenses are adjusted so that the optical axes of the two lenses coincide. The two lenses are then positioned using a tool, and then the initial curing in step (6) is performed.
6. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (5), glue with a viscosity of less than 300 mPa.s can be placed naturally on a horizontal workbench to wait for the glue to spread naturally due to its low viscosity; if the glue viscosity is above 300 mPa.s, the lens after dispensing glue is placed on a clean black cardboard. The lower piece will remain motionless due to friction. Use a rubber stick that will not scratch the surface of the lens to press the upper piece and rotate it clockwise, so that the upper piece rotates spherically around the lower piece clockwise until the glue between the upper and lower lenses is even.
7. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (2), the outer diameter of the negative lens needs to be controlled within ΦD ± 0.004 mm.
8. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (4), the glue needs to be brought from the refrigerator to room temperature before dispensing.
9. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: In step (3), the coating on the bonding surface is a single-layer film, and the film material is either silicon dioxide or magnesium fluoride.
10. The process for processing a laminated lens to prevent deformation according to claim 1, characterized in that: Step (7), the side of the laminated lens with high transmittance faces the UV lamp.