A coating method for relieving face pressure attenuation of a camera lens

Abstract

The present application relates to the technical field of lens coating, and particularly relates to a coating method for relieving face pressure attenuation of camera lens, comprising the following steps: designing a conventional AR film, so that the transmittance of the conventional AR film meets the design requirements; measuring the face pressure value of the lens, coating the conventional AR film on the lens, and measuring the face pressure value of the lens after coating the conventional AR film; coating a single film layer material on the lens, and measuring the face pressure value to analyze the influence of different film layer materials in the AR film on the face pressure value; and designing an optimized AR film meeting the design requirements of the face pressure value according to the influence of different film layer materials on the face pressure value. The coating method for relieving face pressure attenuation of camera lens optimizes and improves the AR film by measuring and analyzing the face pressure of the conventional AR film, analyzing the influence of different film layer materials in the AR film on the face pressure value, obtaining the optimized AR film meeting the design requirements of the face pressure value and the transmittance design requirements, and improving the face pressure value of the lens.

Description

Technical Field

[0001] This invention relates to the field of lens coating technology, and specifically to a coating method for mitigating surface pressure attenuation in camera lenses. Background Technology

[0002] With the arrival of the 5G era and the widespread adoption of smartphones, watches, and other electronic products, consumers' demands for these products are no longer limited to performance and lifespan; they also place increasing emphasis on visual appeal and appearance. While a cool appearance is important, consumers also prioritize scratch resistance and drop durability. Smartphone back covers are relatively thick, approximately 1.1mm, while camera lenses are only 0.4-0.5mm thick. Furthermore, coatings reduce the surface pressure of the camera lens, making its surface pressure significantly lower than that of the phone's back cover. Therefore, developing a thin-film preparation method to reduce surface pressure attenuation in camera lenses is of great research significance in order to ensure compatibility with the back cover and mitigate the impact of coatings on the surface pressure of the camera lens. Summary of the Invention

[0003] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a coating method for mitigating the attenuation of surface pressure on camera lenses.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a coating method for mitigating surface pressure attenuation of camera lenses, comprising the following steps:

[0005] Step 1: Design a conventional AR film to ensure that its transmittance meets the design requirements;

[0006] Step 2: Measure the surface pressure of the lens. Apply a standard AR coating to the lens and measure the surface pressure of the lens after coating.

[0007] Step 3: A single film material is deposited on the lens, and the surface pressure value of the lens is measured to analyze the influence of different film materials in the AR film on the surface pressure value.

[0008] Step 4: Based on the influence of different membrane materials on the surface pressure value, design an optimized AR membrane that meets the surface pressure value design requirements.

[0009] Furthermore, in step 1, a conventional AR film was designed using TFC film system design software. The transmittance design requirement was: for 550nm light, transmittance >94.5%. The film materials selected were high-refractive-index titanium pentoxide (Ti3O5) and low-refractive-index silicon dioxide (SiO2). The film thicknesses were designed as shown in the table below:

[0010]

[0011] For 550nm light, the transmittance is 94.6-94.7%, which meets the transmittance design requirements.

[0012] Furthermore, in step 2, 10 sets of lenses are tested for surface pressure values ​​before and after coating. The unit of surface pressure is Kgf.

[0013] The pressure values ​​before coating are: 28, 27.84, 27.48, 25.35, 26.06, 24.93, 25.97, 27.57, 24.54, 25.28;

[0014] The pressure values ​​after coating are: 7.85, 7.91, 7.32, 8.04, 9.13, 6.92, 6.87, 6.46, 8.13, 8.97;

[0015] The pressure value decreases significantly after coating, failing to meet the design requirement of a total surface pressure value greater than 7 kgf.

[0016] Furthermore, in step 3, the single film material includes a single titanium pentoxide (Ti3O5) and a single silicon dioxide (SiO2). Titanium pentoxide (Ti3O5) and silicon dioxide (SiO2) are individually deposited on the lenses. The surface pressure values ​​of the six lenses are shown in the table below:

[0017]

[0018] By analyzing the surface pressure data of a single-layer film, it was found that the thickness of silicon dioxide is more than twice that of titanium pentoxide, but the surface pressure of silicon dioxide is greater than that of titanium pentoxide. Therefore, it can be concluded that the thickness of titanium pentoxide is the cause of the significant surface pressure attenuation.

[0019] Furthermore, in step 4, the structure and thickness of the membrane materials in the conventional AR membrane are adjusted, and a six-layer membrane structure is designed using TFC membrane system design software to obtain the first optimized AR membrane. The membrane thickness of the first optimized AR membrane is shown in the table below:

[0020]

[0021] Total thickness of titanium pentoxide: 57.8 nm, total thickness of silicon dioxide: 193.8 nm, ratio of total film thickness of single material: silicon dioxide / titanium pentoxide = 3.35;

[0022] The first optimized AR film has a transmittance of 95.5% for 550nm light, which meets the transmittance design requirements.

[0023] Furthermore, a first optimized AR film was deposited on the lens, and the surface pressure value of 10 groups of lenses coated with the first optimized AR film was measured. The unit of surface pressure is Kgf, and the surface pressure value data are: 10.6, 11.28, 10.13, 10.7, 12.75, 10.07, 11.26, 9.86, 12.22, 11.47; which can meet the design requirement that all surface pressure values ​​are greater than 7 Kgf.

[0024] Furthermore, a full set of reliability tests were conducted on the first optimized AR film to determine whether it was qualified.

[0025] Furthermore, in step 4, the thickness of the membrane material in the conventional AR membrane is adjusted, and a five-layer membrane structure is designed using TFC membrane system design software to obtain the second optimized AR membrane. The membrane thickness of the second optimized AR membrane is shown in the table below:

[0026]

[0027] Total thickness of titanium pentoxide: 40.25 nm, total thickness of silicon dioxide: 170.42 nm, ratio of total film thickness of single material: silicon dioxide / titanium pentoxide = 4.23;

[0028] The second optimized AR film has a transmittance of 95.7% for 550nm light, which meets the transmittance design requirements.

[0029] Furthermore, a second optimized AR film was deposited on the lens, and the surface pressure value of 10 groups of lenses coated with the second optimized AR film was measured. The unit of surface pressure is Kgf, and the surface pressure values ​​are: 12.5, 12.16, 12.37, 12.89, 13.15, 13.24, 13.06, 12.61, 12.57, and 13.56. It can meet the design requirement that all surface pressure values ​​are greater than 7 Kgf.

[0030] Furthermore, a full set of reliability tests were conducted on the second optimized AR film to determine whether it was qualified.

[0031] The beneficial effects of the present invention are as follows: As can be seen from the above description of the present invention, compared with the prior art, the coating method of the present invention for mitigating the surface pressure attenuation of camera lenses measures and analyzes the surface pressure of conventional AR films and analyzes the influence of different film layer materials in AR films on the surface pressure value, so as to optimize and improve AR films, obtain optimized AR films that meet the surface pressure value design requirements and the transmittance design requirements, alleviate the surface pressure attenuation of lenses caused by coating, improve the surface pressure value of lenses, and improve lens performance. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the steps of a coating method for mitigating surface pressure attenuation of a camera lens according to Embodiment 1 of the present invention.

[0033] Figure 2 This is a transmittance curve of a conventional AR film in Embodiment 1 of the present invention;

[0034] Figure 3 This is a transmittance curve of the first optimized AR film in Embodiment 1 of the present invention;

[0035] Figure 4 This is a transmittance curve of the second optimized AR film in Embodiment 2 of the present invention. Detailed Implementation

[0036] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Specific Implementation Example 1:

[0039] Reference Figure 1 As shown, a coating method for mitigating surface pressure attenuation in camera lenses includes the following steps:

[0040] Step 1: Design a conventional AR film to ensure that its transmittance meets the design requirements;

[0041] Step 2: Measure the surface pressure of the lens. Apply a standard AR coating to the lens and measure the surface pressure of the lens after coating.

[0042] Step 3: A single film material is deposited on the lens, and the surface pressure value of the lens is measured to analyze the influence of different film materials in the AR film on the surface pressure value.

[0043] Step 4: Based on the influence of different membrane materials on the surface pressure value, design an optimized AR membrane that meets the surface pressure value design requirements.

[0044] The coating method of the present invention for mitigating the surface pressure attenuation of camera lenses involves measuring and analyzing the surface pressure of conventional AR films and analyzing the influence of different film layer materials on the surface pressure value in order to optimize and improve the AR film. This results in an optimized AR film that meets the design requirements for both surface pressure value and transmittance, thereby mitigating the surface pressure attenuation of the lens caused by coating, improving the surface pressure value of the lens, and enhancing the lens performance.

[0045] In this embodiment, in step 1, a conventional AR film is designed using TFC film system design software. The transmittance design requirement is: for 550nm light, transmittance >94.5%. The film material is selected from high-refractive-index titanium pentoxide (Ti3O5) and low-refractive-index silicon dioxide (SiO2). The film thickness is designed as shown in the table below:

[0046]

[0047] Reference Figure 2 As shown, the transmittance for 550nm light is 94.6-94.7%, which meets the transmittance design requirements.

[0048] In this embodiment, in step 2, 10 groups of lenses are tested for surface pressure values ​​before and after coating. The unit of surface pressure is Kgf.

[0049] The pressure values ​​before coating are: 28, 27.84, 27.48, 25.35, 26.06, 24.93, 25.97, 27.57, 24.54, 25.28;

[0050] The pressure values ​​after coating are: 7.85, 7.91, 7.32, 8.04, 9.13, 6.92, 6.87, 6.46, 8.13, 8.97;

[0051] The pressure value decreases significantly after coating, failing to meet the design requirement of a total surface pressure value greater than 7 kgf.

[0052] Taking a 0.4mm thick lens as an example, the surface pressure of the lens before coating is approximately 24-28 kgf. After the electroplating process, the strength of the glass decreases, which is reflected in the lower surface pressure. The surface pressure of the incoming material before coating is above 24 kgf, but after electroplating, the surface pressure decreases significantly to only about 6-8 kgf. In fact, after electroplating, stress exists not only between the coating layers but also between the coating layer and the lens. The mismatch between these stresses leads to a significant decrease in lens strength.

[0053] The design requirement for surface pressure is >7Kgf, but the existing technology can only achieve 6-8Kgf, and occasionally <7, which poses a risk of non-compliance and urgently needs to be addressed.

[0054] Surface pressure test method: Using a surface pressure tester, place the camera lens with the uncoated side facing up and the coated side facing down on the support platform, and move the test head downwards at a certain speed until it contacts the uncoated side of the lens until it bursts. The displayed surface pressure value is the surface pressure value of the lens.

[0055] In this embodiment, in step 3, the single film material includes a single titanium pentoxide (Ti3O5) and a single silicon dioxide (SiO2). Titanium pentoxide (Ti3O5) and silicon dioxide (SiO2) are individually deposited on the lenses. The surface pressure values ​​of the six lenses are shown in the table below:

[0056]

[0057] By analyzing the surface pressure data of a single-layer film, it was found that the thickness of silicon dioxide is more than twice that of titanium pentoxide, but the surface pressure of silicon dioxide is greater than that of titanium pentoxide. Therefore, it can be concluded that the thickness of titanium pentoxide is the cause of the significant surface pressure attenuation.

[0058] Given that the lens thickness and material are fixed and cannot be changed, the only solution is to address the issue through the design of the electroplating coating system. Currently available electroplating coating materials are only high-refractive-index titanium pentoxide and low-refractive-index silicon dioxide; therefore, the influence of a single coating material on the surface pressure value needs to be analyzed.

[0059] From the surface pressure data of the single film layer above, it can be seen that the thickness of silicon dioxide is more than twice that of titanium pentoxide, but its surface pressure is much greater, about 3-4 times that of titanium pentoxide. Therefore, it can be concluded that the significant surface pressure attenuation is caused by the thickness of titanium pentoxide. In contrast, the total thickness of a conventional AR film system is 146 nm for titanium pentoxide and 129 nm for silicon dioxide. Their thicknesses are nearly 1:1, and titanium pentoxide is thicker than silicon dioxide, which leads to such a significant decrease in the surface pressure of the lens after electroplating. Therefore, to improve the surface pressure value, the total thickness of titanium pentoxide should be as small as possible compared to the total thickness of silicon dioxide.

[0060] In this embodiment, in step 4, based on the transmittance requirement at 550nm: transmittance > 94.5% and the idea that the total thickness of titanium pentoxide should be as small as possible compared to the total thickness of silicon dioxide, the structure and thickness of the film materials in the conventional AR film are adjusted. A six-layer film system structure is designed using TFC film system design software to obtain the first optimized AR film. The film system thickness of the first optimized AR film is shown in the table below:

[0061]

[0062] Total thickness of titanium pentoxide: 57.8 nm, total thickness of silicon dioxide: 193.8 nm, ratio of total film thickness of single material: silicon dioxide / titanium pentoxide = 3.35;

[0063] Reference Figure 3 As shown, the first optimized AR film has a transmittance of 95.5% for 550nm light, which meets the transmittance design requirements.

[0064] In this embodiment, a first optimized AR film is deposited on the lens, and the surface pressure values ​​of 10 groups of lenses with the first optimized AR film are measured. The unit of surface pressure is Kgf, and the surface pressure value data are: 10.6, 11.28, 10.13, 10.7, 12.75, 10.07, 11.26, 9.86, 12.22, 11.47; which can meet the design requirement that all surface pressure values ​​are greater than 7 Kgf.

[0065] In this embodiment, a full set of reliability tests is performed on the first optimized AR film to determine whether the first optimized AR film is qualified.

[0066] The specific data is shown in the table below:

[0067]

[0068]

[0069] The plated products underwent routine reliability testing. The plating layer did not peel off during both dry cross-cut and boiled cross-cut tests, confirming the effect was OK and the overall reliability was OK. Specific Implementation Example 2:

[0071] The difference between this embodiment and Embodiment 1 is that, in step 4, based on the transmittance requirement at 550nm (transmittance > 94.5%) and the principle that the total thickness of titanium pentoxide should be as small as possible compared to the total thickness of silicon dioxide, the thickness of the film materials in the conventional AR film is adjusted. A five-layer film structure is designed using TFC film system design software to obtain the second optimized AR film. The film thickness of the second optimized AR film is shown in the table below:

[0072]

[0073] Total thickness of titanium pentoxide: 40.25 nm, total thickness of silicon dioxide: 170.42 nm, ratio of total film thickness of single material: silicon dioxide / titanium pentoxide = 4.23;

[0074] Reference Figure 4 As shown, the second optimized AR film has a transmittance of 95.7% for 550nm light, which meets the transmittance design requirements.

[0075] In this embodiment, a second optimized AR film is deposited on the lens, and the surface pressure values ​​of 10 groups of lenses coated with the second optimized AR film are measured. The unit of surface pressure is Kgf, and the surface pressure value data are: 12.5, 12.16, 12.37, 12.89, 13.15, 13.24, 13.06, 12.61, 12.57, and 13.56. This meets the design requirement that all surface pressure values ​​are greater than 7 Kgf.

[0076] In this embodiment, a full set of reliability tests is performed on the second optimized AR film to determine whether the second optimized AR film is qualified.

[0077] The specific data is shown in the table below:

[0078]

[0079]

[0080] The plated products underwent routine reliability testing. The plating layer did not peel off during both dry cross-cut and boiled cross-cut tests, confirming the effect was OK and the overall reliability was OK.

[0081] Without causing conflict, those skilled in the art can freely combine and use the above-mentioned additional technical features.

[0082] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A coating method for mitigating surface pressure attenuation in camera lenses, characterized in that, Includes the following steps: Step 1: Design a conventional AR film. The film material is selected from high-refractive-index titanium pentoxide (Ti3O5) and low-refractive-index silicon dioxide (SiO2) to ensure that the transmittance of the conventional AR film meets the design requirements. Step 2: Measure the surface pressure of the lens, apply a conventional AR coating to the lens, and measure the surface pressure of the lens after coating. Step 3: Deposit a single film material on the lens. The single film material includes a single titanium pentoxide (Ti3O5) and a single silicon dioxide (SiO2). Deposit Ti3O5 and SiO2 separately on the lens and measure the surface pressure value of the lens. By analyzing the surface pressure data of the single film thickness, the influence of different film materials in AR film on the surface pressure value can be analyzed. Step 4: Based on the influence of different membrane materials on the surface pressure value, adjust the structure and thickness of the membrane materials in the conventional AR membrane, and design an optimized AR membrane that meets the surface pressure value design requirements; The ratio of total film thickness of a single material is: silicon dioxide / titanium pentoxide = 3.35, or the ratio of total film thickness of a single material is: silicon dioxide / titanium pentoxide = 4.

23.

2. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 1, characterized in that, In step 1, a conventional AR film was designed using TFC film system design software. The transmittance design requirement was: for 550nm light, transmittance > 94.5%. The film thickness was designed as shown in the table below: For 550nm light, the transmittance is 94.6-94.7%, which meets the transmittance design requirements.

3. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 1, characterized in that, In step 2, 10 sets of lenses were tested for surface pressure before and after coating. The unit of surface pressure is Kgf. The pressure values ​​before coating are: 28, 27.84, 27.48, 25.35, 26.06, 24.93, 25.97, 27.57, 24.54, 25.28; The pressure values ​​after coating are: 7.85, 7.91, 7.32, 8.04, 9.13, 6.92, 6.87, 6.46, 8.13, 8.97; The pressure value decreases significantly after coating, failing to meet the design requirement of a total surface pressure value greater than 7 kgf.

4. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 1, characterized in that, In step 3, the surface pressure values ​​of the six lenses are shown in the table below: It was found that the thickness of silicon dioxide is more than twice that of titanium pentoxide, but the surface pressure of silicon dioxide is greater than that of titanium pentoxide. Therefore, it can be concluded that the thickness of titanium pentoxide is the cause of the significant decrease in surface pressure.

5. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 1, characterized in that, In step 4, a six-layer membrane structure is designed using TFC membrane design software to obtain the first optimized AR membrane. The membrane thickness of the first optimized AR membrane is shown in the table below: Total thickness of titanium pentoxide: 57.8 nm; Total thickness of silicon dioxide: 193.8 nm; The first optimized AR film has a transmittance of 95.5% for 550nm light, which meets the transmittance design requirements.

6. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 5, characterized in that, The first optimized AR film was coated on the lens, and the surface pressure value of 10 groups of lenses coated with the first optimized AR film was measured. The unit of surface pressure is Kgf. The surface pressure values ​​are: 10.6, 11.28, 10.13, 10.7, 12.75, 10.07, 11.26, 9.86, 12.22, 11.

47. It can meet the design requirement that all surface pressure values ​​are greater than 7 Kgf.

7. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 5, characterized in that, A full set of reliability tests was conducted on the first optimized AR film to determine whether it was qualified.

8. The coating method for mitigating surface pressure attenuation of camera lenses according to claim 1, characterized in that, In step 4, the thickness of the membrane material in the conventional AR membrane is adjusted, and a five-layer membrane structure is designed using TFC membrane system design software to obtain the second optimized AR membrane. The membrane thickness of the second optimized AR membrane is shown in the table below: Total thickness of titanium pentoxide: 40.25 nm; Total thickness of silicon dioxide: 170.42 nm; The second optimized AR film has a transmittance of 95.7% for 550nm light, which meets the transmittance design requirements.

9. A coating method for mitigating surface pressure attenuation of camera lenses according to claim 8, characterized in that, A second optimized AR coating was deposited on the lens, and the surface pressure value of 10 groups of lenses coated with the second optimized AR coating was measured. The unit of surface pressure is Kgf. The surface pressure values ​​are: 12.5, 12.16, 12.37, 12.89, 13.15, 13.24, 13.06, 12.61, 12.57, and 13.

56. It can meet the design requirement that all surface pressure values ​​are greater than 7 Kgf.

10. A coating method for mitigating surface pressure attenuation of camera lenses according to claim 8, characterized in that, A full set of reliability tests was conducted on the second optimized AR film to determine whether it was qualified.

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