KR20230023682A - A Method for Producing a Coating Lens - Google Patents

Abstract

The present invention relates to a method for manufacturing a coated lens. The method for manufacturing a coated lens includes the steps of: preparing a lens substrate; cleaning the lens substrate; wiping the surface of the cleaned lens substrate; forming a coated layer by a vacuum deposition method; and curing the coated layer. An objective of the present invention is to provide the method for manufacturing a coated lens having thermal shock resistance, weather resistance and fire resistance while forming multiple coated layers by a vacuum deposition method.

Description

Method for producing a coated lens {A Method for Producing a Coating Lens}

The present invention relates to a method for manufacturing a coated lens, and specifically to a method for manufacturing a coated lens having a plurality of coating layers.

A lens corresponding to an optical means for collecting or dispersing light by refraction may be made of a transparent material such as glass or made of glass or plastic. Various types of coating layers may be formed on the lens made of such a material to suit the purpose of use of the lens. For example, an anti-reflection coating layer may be formed on a lens for glasses to prevent glare and secure a clear view. In addition, in the case of a camera lens, a lens of a car lamp, or a lens of a rearview mirror, it is necessary to be appropriately coated according to each use environment or purpose. In relation to such a coated lens, Patent Publication No. 10-2019-0010221 discloses a hybrid infrared optical lens having ta_c and Y ₂ O ₃ coating thin film layer. In addition, Patent Publication No. 10-2019-0053865 discloses an optical lens comprising an antireflection coating on one of the main surfaces, which greatly reduces reflection of visible light over a wide range of incident angles. In addition, Patent Publication No. 10-2019-0020406 discloses a method for coating sunglasses lenses by vacuum deposition. The lens coating layer needs to be formed so as not to degrade the performance of the lens itself while being formed to have a function according to the purpose of the lens. For example, the lens coating layer needs to have sufficient strength for a protective function while basically having a high transmittance. In addition, it is necessary to have chemical resistance while having sufficient resistance to heat-shock according to the use environment. However, the prior art does not disclose a method for forming a coating layer of a lens having such characteristics.

The present invention is to solve the problems of the prior art and has the following object.

Prior Art 1: Patent Publication No. 10-2019-0010221 (Korea Institute of Optical Technology, 2019.01.30. Publication) Hybrid infrared optical lens with ta-C and Y2O3 coating thin film layer Prior Art 2: Patent Publication No. 10-2019-0053865 (Essillo Anternacional, published on May 20, 2019) Optical lens including an antireflection coating having multiangular efficiency Prior Art 3: Patent Publication No. 10-2019-0020406 (Yoo Heung-sang, 2019.03.04. Publication) Sunglasses lens coating method by vacuum deposition

An object of the present invention is to provide a method for manufacturing a coated lens having thermal shock resistance, weather resistance and fire resistance while forming multiple coating layers by a vacuum deposition method.

According to a preferred embodiment of the present invention, a method for manufacturing a coated lens includes preparing a lens substrate; The step of cleaning the lens substrate; Wiping the surface of the cleaned lens substrate; Forming a coating layer by a vacuum deposition method; and curing the coating layer.

According to another suitable embodiment of the present invention, the step of wiping the surface is carried out by a wool, cotton fiber, non-woven fabric, natural fiber or man-made fiber.

According to another preferred embodiment of the present invention, the coating layer consists of 9 to 12 identical or different material layers.

According to another preferred embodiment of the present invention, the coating layer consists of multiple layers formed of a material selected from the group consisting of Ti ₃ O ₅ , SiO _{2 ,} MgF ₂ , Al ₂ O ₃ and SiO ₂ /Al ₂ O ₃ .

The method for manufacturing a coated lens according to the present invention prevents deterioration of transmittance of multiple coating layers and peeling in a humid environment. The manufacturing method according to the present invention enables the formation of a coating layer having film strength and weather resistance that can be used in an external environment or an extreme environment, while preventing the occurrence of scratches or scratches due to impact by foreign substances in a use environment. The manufacturing method according to the present invention can be applied to a lens for a vehicle, preferably applied to a coating of a camera lens of an autonomous vehicle, but is not limited thereto.

1 shows an embodiment of a method for manufacturing a coated lens according to the present invention.
Figure 2 shows another embodiment of the manufacturing method of the coated lens according to the present invention.
Figure 3 shows an embodiment of the coating layer formed by the manufacturing method according to the present invention.
Figures 4a and 4e show the results of the characteristic test for the coated lens manufactured by the manufacturing method according to the present invention.

Below, the present invention will be described in detail with reference to the embodiments presented in the accompanying drawings, but the embodiments are for a clear understanding of the present invention, and the present invention is not limited thereto. In the following description, components having the same reference numerals in different drawings have similar functions, so repeated descriptions are not made unless necessary for understanding the invention, and well-known components are briefly described or omitted, but the present invention It should not be understood as being excluded from the embodiment of.

1 shows an embodiment of a method for manufacturing a coated lens according to the present invention.

Referring to Figure 1, the manufacturing method of the coated lens step (P11) to prepare a lens substrate; The lens substrate is first washed and centering is inspected (P12); Step of wiping the surface of the primary washed lens substrate (P13); Forming a coating layer by a vacuum deposition method (P15); and step 16 where the coating layer is cured.

The lens substrate may be made of glass, synthetic resin, or a similar material according to the purpose of the lens, and may have various apertures or focal points. For example, the lens substrate may be prepared through substrate material preparation, double-side roughing, double-side finishing, and double-side polishing processes (P11). The refractive index, dimension, focus, curvature, or thickness of the lens substrate may be inspected, and the lens substrate may be first washed (P12). The primary cleaning is to fix each lens to the cleaning holder, and may be washed with, for example, isopropyl alcohol (IPA), but is not limited thereto, and may be washed with various solutions such as distilled water or ethyl alcohol, The present invention is not limited thereby. Appearance can be inspected for the lens base material that has undergone primary washing, for example, scratches. It can be a scratch test, a stain test, or a variety of similar visual tests. When such an appearance inspection is completed, it may be an infatuation inspection or a centering inspection (P12). In the centering inspection process, the black lacquer depth or centering position can be set. Thereafter, an outer diameter, eccentricity, step difference, or Sag (Sagittal Height) test may be performed on the lens substrate for which centering has been set. Upon completion of such inspection, a process of wiping the surface of the lens substrate may proceed (P13). The coating layer formed on the lens substrate may be exfoliated in an external environment, and in particular, in the case of a lens for an automobile camera, the coating layer may be exposed to various external environments and peeling may occur over time. The process of wiping the surface may have a function of increasing the adhesion property of the coating layer to the lens substrate or the strength of the coating layer. In this way, the process of wiping the coating layer of the lens substrate may function to improve strength characteristics, anti-peeling characteristics, or adhesion characteristics of the coating layer. The wiping process may be performed with, for example, wool, cotton fiber, non-woven fabric, natural fiber or artificial fiber, and may be performed in an acetal jig. Specifically, at least one scrubbing groove corresponding to the surface shape of the lens substrate may be formed in the acetal jig, and pad-shaped or plate-shaped fleece, cotton fiber, nonwoven fabric, natural fiber, or artificial fiber may be formed in each scrubbing groove. The made rubbing material may be prepared. In addition, the surface of the lens to be coated may come into contact with the rubbing material to perform a wiping process. In the course of the wiping process, there should be no flaws or scratches caused by the lens material on the surface of the lens. To this end, the rubbing material may be made of a soft material with low frictional force, and isopropyl alcohol, distilled water, or various liquids similar thereto that can reduce the friction coefficient may be used in a state in which the rubbing material is absorbed. The contact pressure of the lens substrate may be, for example, 1 to 500,000 pa, and the friction coefficient of the rubbing material may be adjusted to be 0.2 or less. The rubbing process may be performed while the lens substrate rotates at a speed of, for example, 0.01 to 10 (times/sec) or reciprocates at a speed of 0.01 to 10 m/sec. The rubbing process or wiping process may be performed in various ways and is not limited to the presented embodiment. When such a wiping process is completed (P13), an inspection process and a secondary cleaning process may optionally be performed (P14). The inspection process may be, for example, a visual inspection process, and cleaning may be performed by a cleaning solution such as isopropyl alcohol. When such a washing process is completed, a coating process may proceed (P15). The coating process may be performed in a vacuum deposition method, and may be performed in, for example, a vacuum deposition device or a magnetron sputtering device. According to one embodiment of the present invention, the coating layer may be made of 9 to 12 identical or different material layers. In addition, the coating layer may be formed of a material selected from the group consisting of Ti ₃ O ₅ , SiO _{2 ,} MgF ₂ , Al ₂ O ₃ and SiO ₂ /Al ₂ O ₃ . Depending on the structure of the lens, the block face may be coated after the concave face is coated. In this way, when both sides are coated, spectroscopic measurement may be performed after one side is coated. In addition, after washing with a washing solution such as isopropyl alcohol and drying, the other surface may be coated. For example, the concave surface may be coated, followed by spectroscopic measurement, washing, and drying, and then the convex surface may be coated. The coating layer may include a plurality of sub-coating layers, and different sub-coating layers may have the same or different thicknesses. Alternatively, the different sub-coating layers may be formed of the same or different materials. Ti ₃ O ₅ forming the sub-coating layer has the advantage of excellent refractive index, and SiO ₂ has the advantage of good transmittance, excellent film strength, and good transmittance. In contrast MgF ₂ has an excellent transmittance, but has a disadvantage of exfoliation at high humidity. In addition, SiO ₂ /Al ₂ O ₃ has excellent transmittance, but has a disadvantage in that stains or scratches occur on the coated surface. Therefore, the formation order and thickness of the sub-coating layer may be adjusted based on the advantages and disadvantages of each material. For example, the sub-coating layer may be formed in the same order as in STSTSTSTATS, and T, S and A represent Ti ₃ O ₅ , SiO ₂ and Al ₂ O ₃ , respectively. The thickness of each sub-layer may be 20 to 2,000 nm. A plurality of sub-coating layers may be formed in various orders or in various thicknesses, and are not limited to the presented embodiments. When a coating layer composed of 9 to 12 sub-layers is formed in the same way (P15), the coated lens may be cured (P16). Curing may proceed for 1 to 5 hours at a temperature of 120 to 200 °C, for example. When this curing process is completed (P16), the coated lens may be post-treated (P17). The post-treatment process may include, for example, a process such as surface treatment or drying of the coated lens. Also, depending on the type of lens, it may be a black lacquer process for the coated lens.

Below, such a process is described.

Figure 2 shows another embodiment of the manufacturing method of the coated lens according to the present invention.

Referring to FIG. 2 , after the coating layer is formed, an additional process may be performed according to the purpose of the lens. When the coating layer is formed (P15), it may be washed with a cleaning solution such as isopropyl alcohol (P21) and dried. In addition, a spectroscopic test and an initial contact angle test may be performed, and water repellency may be confirmed by the contact angle test. Thereafter, the stabilization process of the coated lens may proceed by leaving it for 50 to 100 hours. In the case of a composite lens, a bonding process may be performed (P22). In addition, a black lacquer process may be performed on the single coated lens or the bonded coated lens (P23). The black lacquer process may be performed with a material such as Epora paint or GT7 to form various films capable of preventing diffuse reflection of the lens due to chromatic aberration, spherical aberration, or astigmatism. The black lacquer material can be made of various materials that have chemical durability and transmittance of 0 in all wavelength regions, and are not limited to the presented examples. When the black lacquer process is completed (P23), dimensional inspection, double band inspection, white spot inspection, or scratch inspection may be performed, and then the coated lens may be cured as described above (P16). In addition, the coating process may be completed after various inspections such as outer diameter, eccentricity, and coating surface reflection inspection are performed on the cured coated lens. The manufacturing process of the coated lens may be completed through various post-processing processes, and is not limited to the presented embodiment.

Figure 3 shows an embodiment of the coating layer formed by the manufacturing method according to the present invention.

Referring to FIG. 3 , a plurality of sub-coating layers CL_1 to CL_N may be formed on the lens substrate LB by the manufacturing method of the coated lens according to the present invention. For example, the sub-coating layers CL_1 to CL_N may be formed in the same order as in STSTSTSTATS, and T, S, and A represent Ti ₃ O ₅ , SiO ₂ and Al ₂ O ₃ , respectively. Each sub-coating layer (CL_1 to CL_N) has, for example, 200 to 300 (S), 70 to 120 (T), 500 to 700 (S), 15 to 50 (T), 1,200 to 1,500 (S), 120 It may have a coating thickness of from 9 to 180 (T), 270 to 320 (S), 620 to 700 (T), 70 to 100 (A), 250 to 350 (T), 900 to 980 (S), The unit is nm. The total coating thickness (L) may be 2 to 10 μm, preferably 3 to 6 μm, and most preferably 4 to 5 μm, but is not limited thereto. The coated lens can be made by various methods, and test results for the coated lens manufactured by the manufacturing method according to the present invention will be described below.

Figures 4a and 4e show the results of the characteristic test for the coated lens manufactured by the manufacturing method according to the present invention.

In the characteristic test of FIG. 4a, the structure of the coating layer is as follows, the thickness unit is nm, S, T and A represent SiO ₂ , Ti ₃ O ₅ and Al ₂ O ₃ respectively, and in the examples of 3b to 3e same.

(i) Lens substrate: LaF ₃ glass material

(ii) sub-coating layer: STSTSTSTATS (11 layers)

(iii) Thickness (nm): A: 70-90; STSTSTST: 3,300 to 3,500; TS: 1,100 to 1,400

(iv) Thermal shock test: 110 ° C / 2 hours left

(v) Acid resistance test: sulfuric acid undiluted solution / left for 2 hours

(vi) The penetrating power was tested by Kavas measuring equipment, and the scratch test was performed by scratching the coated surface with a cutter, and the stain test was performed by applying black lacquer on the coated surface.

Referring to (a) of FIG. 4A , as shown in the thermal shock and acid resistance test results on the left, it can be seen that the coated lens according to the present invention has high acid resistance while being resistant to thermal shock. In addition, it was confirmed that scratches did not occur when scratched with a cutter, and no stains were left. Also, referring to (b) of FIG. 4A, the X axis represents the wavelength (nm) and the Y axis represents the reflectance (Reflectance:%), respectively, Automatic Optical Inspection (AOI) = 0 degrees (400 to 700 nm: blue) and Ravg < 0.8%, Rabs < 1.0% at 45 degrees (400-700 nm); And it can be seen that Ravg ≤ 1.5% and Rabs ≤ 2.5%.

Characteristic test conditions of FIGS. 4B to 4E are as follows, and the test was performed in the same manner as in FIG. 4A.

Figure 4b:

(i) Lens substrate: Hoya's FC5 lens

(ii) Sub-coating layer: SA1TA2TA3TS (8 layers)

(iii) Thickness (nm): A3: 90-120; A2: 250 to 280; A1 450 to 500; TS: 850 to 1,200; T: 80 to 100; S: 1,500 to 2,000

Figure 4c:

(i) Lens substrate: Hoya's TAFD25 lens

(ii) sub-coating layer: STSTSTSTATS (11 layers)

(iii) Thickness (nm): A: 70-90; STSTSTST: 3,300 to 3,500; TS: 1,100 to 1,400

Figure 4d:

(i) Lens substrate: Hoya's TAC8 lens

(ii) sub-coating layer: STSTSTSTATS (11 layers)

(iii) Thickness (nm): A: 70-90; STSTSTST: 3,300 to 3,500; TS: 1,100 to 1,400

Figure 4e:

(i) Lens substrate: Hoya's FDS18W lens

(ii) sub-coating layer: STSTSTSTATS (11 layers)

(iii) Thickness (nm): A: 70-90; STSTSTST: 3,300 to 3,500; TS: 1,100 to 1,400

Referring to Figures 4b to 4e, as shown in the thermal shock and acid resistance test results on the left, it can be seen that the coated lens according to the present invention has high acid resistance while being resistant to thermal shock. In addition, it was confirmed that scratches did not occur when scratched with a cutter, and no stains were left. In the graph on the right, the X axis represents the wavelength (nm) and the Y axis represents the reflectance (Reflectance:%), respectively, AOI (Automatic Optical Inspection) = 0 degree (400 to 700 nm: blue) and 45 degrees (400 to 700 nm) Ravg ≤ 0.8%, Rabs ≤1.0%; And it can be seen that Ravg ≤ 1.5% and Rabs ≤ 2.5%.

In each test, the thickness of SiO ₂ and Ti ₃ O ₅ forming the sub-coating layer was adjusted, and the thickness of the SiO ₂ and Ti ₃ O ₅ sub-coating layer may be appropriately adjusted according to the use environment. . The thickness of each sub-coating layer was adjusted so that the thickness ratio of SiO ₂ : Ti ₃ O ₅ = 1,000: 50 to 1,200. As can be seen from the test results, it can be seen that the coated lens prepared by the method according to the present invention has high resistance to thermal shock, acid resistance, scratches or stains, and therefore can be used in harsh outdoor environmental conditions. For example, the coated lens manufactured by the method according to the present invention can be used as a lens for automobiles and a lens for surveillance cameras applied to autonomous vehicles, but is not limited thereto.

Although the present invention has been described in detail with reference to the presented embodiments above, those skilled in the art will be able to make various modifications and variations without departing from the technical spirit of the present invention with reference to the presented embodiments. . The present invention is not limited by these variations and modifications, but is limited only by the claims appended below.

P11: Preparing the lens substrate P12: Cleaning and centering inspection
P13: Wiping the surface P14: Cleaning
P15: coating layer formation P16: curing
P17: post-processing

Claims (1)

preparing a lens substrate;
The step of cleaning the lens substrate;
Wiping the surface of the cleaned lens substrate;
Forming a coating layer by a vacuum deposition method; and
Including the step of curing the coating layer,
The step of wiping the surface is performed on a pad-shaped or plate-shaped scrubbing material made of fluff, cotton fiber, non-woven fabric, natural fiber or artificial fiber prepared in at least one scrubbing groove corresponding to the surface shape of the lens substrate formed in the acetal jig. The lens surface is contacted and progresses,
The coating layer formed by the vacuum deposition method consists of 9 to 12 multiple layers formed of a material selected from the group consisting of Ti ₃ O ₅ , SiO _{2 ,} MgF ₂ , Al ₂ O ₃ and SiO ₂ /Al ₂ O ₃ Method for manufacturing a coated lens, characterized in that.

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