Lens

Abstract

The present disclosure relates to a lens including: a lens portion having a protruding pattern formed on a surface of the lens portion, the protruding pattern including a plurality of protrusions and a plurality of grooves; and a waterproof layer disposed on the surface of the lens portion, in which when a percentage of an average area of the grooves in an area of the surface per 1 mm2 of the surface of the lens portion is referred to as a spatial area ratio, the spatial area ratio is 20% or more.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0056043, filed on April 26, 2024, with the Korean Intellectual Property Office, and Korean Patent Application No. 10-2024-0129756, filed on September 25, 2024, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure relates to lenses. Background Technology

[0004] The phenomenon of wetting or dehydration on a surface is a technology that can be applied not only to the IT and electronics fields but also to the cosmetics field, and therefore, it has already begun to emerge.

[0005] This technology can be used in various fields that require superhydrophobic properties that repel water droplets, superhydrophilic properties that form thin films without forming water droplets, and self-cleaning properties that remove foreign matter.

[0006] Here, the amount of water droplets that can be contained on the surface is determined based on the contact angle, and if the contact angle is greater than 90°, the surface is considered to be waterproof, and if the contact angle is less than 90°, the surface is considered to be hydrophilic.

[0007] To make them applicable to a variety of products, coating agents for waterproof coatings have been commercialized, and these waterproof coating agents can be organic and can be linked within the main structures of CO, CH, CC, and CF through their own bonding energies.

[0008] However, when exposed to UV rays for extended periods, the CO and CC structures (which have energy levels lower than or similar to the UV wavelength) become disconnected and lose their original waterproof coating properties.

[0009] Therefore, in products equipped with multiple cameras in the electronics and IT fields, the superhydrophobic state of the lens must be maintained for a long time even in humid environments, and must remain reliable so that the user's eyes do not feel uncomfortable. As a result, various coating agents have been developed to meet these requirements.

[0010] On the other hand, electronic products such as those used in vehicles must maintain the superhydrophobic properties and self-cleaning function of camera lenses for extended periods, even in environments such as fog or rain, to ensure the driver's vision and safety.

[0011] Therefore, a technical solution may be needed for camera lenses used in vehicle electronic devices that can maintain the superhydrophobic properties of the lens for a long time even under UV exposure.

[0012] The above information is presented as background information and is intended to aid in understanding this disclosure. No determination or assertion is made as to whether any of the above content constitutes an application of prior art to this disclosure. Summary of the Invention

[0013] This summary is provided to present the selection of concepts in a simplified form, while these concepts are further described in the following detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter.

[0014] In one general aspect, a lens includes: a lens portion having a protruding pattern formed on a surface of the lens portion, the protruding pattern including a plurality of protrusions and a plurality of grooves; and a waterproof layer disposed on the surface of the lens portion, wherein, for every 1 mm of the lens portion... 2 When the percentage of the average area of ​​the grooves on a surface to the area of ​​the surface is called the space area ratio, the space area ratio is 20% or greater.

[0015] The height of the protrusion in the lens section can be 2 μm or greater.

[0016] In the lens section, when the length of the major axis of one of the protrusions is the first length and the length between the longest portions of one of the grooves is the second length, the difference between the first length and the second length can be 20 μm or greater.

[0017] In the lens section, the height of the protrusion can be 2 μm or greater, and in the lens section, when the length of the major axis of one of the protrusions is a first length and the length between the longest portions of one of the grooves is a second length, the difference between the first length and the second length can be 20 μm or greater.

[0018] The protrusion can be formed into a polygonal or circular shape.

[0019] The lens may also include an adhesive layer disposed between the lens portion and the waterproof layer.

[0020] The lens may also include an anti-reflective (AR) coating portion disposed between the lens portion and the waterproof layer.

[0021] The lens may also include an adhesive layer disposed between the AR coating portion and the waterproof layer.

[0022] The AR coating portion may include at least one material layer selected from the group consisting of siloxane, SiO2, SiON, Si3N4, TiO2, TiON and TiN.

[0023] The AR coating portion may include a multilayer structure in which a first layer and a second layer with different refractive indices are alternately stacked once or multiple times.

[0024] Other features and aspects will become apparent from the following detailed description, drawings, and claims. Attached Figure Description

[0025] Figure 1 This is a schematic diagram illustrating a patterning process using a photoresist (PR) mask method.

[0026] Figure 2 This is a schematic diagram illustrating a patterning process using a metal hard mask method.

[0027] Figure 3 It is a photograph showing a portion of the lens section with a raised pattern formed on a surface through micro-patterning.

[0028] Figures 4 to 7 It is a plan view showing various shapes of prominent patterns according to one or more exemplary embodiments of the present disclosure.

[0029] Figure 8 This is a schematic cross-sectional view of a lens according to an exemplary embodiment of the present disclosure.

[0030] Figure 9 This is a schematic cross-sectional view of a lens according to another exemplary embodiment of the present disclosure.

[0031] Figures 10 to 14 This is a diagram showing how the contact angle of the lens varies with the spatial area ratio of the grooves when the depth of the grooves is different.

[0032] Figure 15 This is a graph showing the transmittance based on the WS value.

[0033] Throughout the accompanying drawings and detailed embodiments, the same reference numerals denote the same elements unless otherwise described. For clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative dimensions, scale, and depiction of elements in the drawings may be exaggerated. Detailed Implementation

[0034] In the following text, although examples of this disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0035] The following detailed embodiments are provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be apparent upon understanding this disclosure. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein, but can be altered as will become apparent upon understanding this disclosure, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0036] The features described herein may be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided merely to illustrate some of the many possible ways in which the methods, apparatuses, and / or systems described herein will be apparent upon understanding this disclosure.

[0037] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on," "connected to," or "attached to" another element, it may be directly "on," directly "connected to," or directly "attached to" the other element, or there may be one or more other elements in between. Conversely, when an element is described as being "directly" "on," "directly connected to," or "directly attached to" another element, there are no other elements in between.

[0038] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more of the associated listed items; similarly, “at least one of…” includes any one of the associated listed items and any combination of any two or more of the associated listed items.

[0039] Although terms such as “first,” “second,” and “third” may be used in this document to describe various components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, the first component, first assembly, first region, first layer, or first part mentioned in the examples described herein may also be referred to as a second component, second assembly, second region, second layer, or second part without departing from the teachings of the examples.

[0040] For ease of description, spatial relative terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. In addition to the orientation depicted in the drawings, these spatial relative terms are intended to also include different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as “above” or “upper” relative to another element will consequently be “below” or “lower” relative to said other element. Therefore, the term “above” includes both upper and lower orientations, depending on the spatial orientation of the device. The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used herein will be interpreted accordingly.

[0041] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. The terms “a,” “an,” and “the” are intended to include the plural meaning as well, unless the context clearly indicates otherwise. The terms “comprising,” “including,” and “having” specify the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0042] The shapes shown in the accompanying drawings may vary due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the accompanying drawings, but include shape variations that occur during manufacturing.

[0043] In this article, it is important to note that the term “may” is used with respect to examples. For example, regarding what an example may include or implement, it means that there exists at least one example that includes or implements this feature, but not all examples are limited to this.

[0044] As will be apparent upon understanding this disclosure, the features of the examples described herein can be combined in various ways. Furthermore, although the examples described herein have multiple configurations, other configurations are also possible, as will be apparent upon understanding this disclosure.

[0045] One aspect of this disclosure is to provide a lens that achieves superhydrophobicity.

[0046] In order to manufacture the lens of this disclosure, firstly, a lens portion with a prominent pattern is formed by micro-patterning the lens portion that serves as the base of the lens.

[0047] In an exemplary embodiment, a photoresist (PR) or a hard metal mask may be applied to form a protruding pattern on the lens portion through micropatterning.

[0048] Figure 1 A rough illustration of the patterning process using the PR mask method is provided. Figure 1 As shown, patterning using a PR mask is performed in the following order: a PR 200 with an opening 210 is provided on the lens portion 100, a groove 110 is formed in the surface of the lens portion 100 by dry etching or wet etching, a plurality of protrusions 120 are formed, and then the PR 200 is removed.

[0049] Figure 2 This diagram schematically illustrates a patterning process using a hard metal mask method. (See reference...) Figure 2 The patterning using a hard metal mask is performed in the following order: a PR300 with an opening 310 is provided on the lens portion 100, a hard metal mask 400 is deposited on them, the PR300 and the portion 420 of the hard metal mask 400 deposited on the PR300 are stripped together, dry etching or wet etching is performed using a metal layer 410 (the remaining portion of the hard metal mask 400 with an opening 430) to form a groove 110 on the surface of the lens portion 100 to form a plurality of protrusions 120, and then the metal layer 410 is removed.

[0050] Here, the metal hard mask 400 can be formed of a material including chromium (Cr), nickel (Ni), titanium (Ti), copper (Cu), tungsten, aluminum (Al) or at least one of them.

[0051] Figure 3 It is a photograph showing a portion of the lens section in which a raised pattern is formed on a surface through micro-patterning.

[0052] Furthermore, the salient patterns formed through micro-patterning can have various shapes such as polygons or circles.

[0053] For example, each protrusion of the protruding pattern can be formed as follows: Figure 4 The hexagon shown is formed as follows Figure 5 The triangle shown is formed as follows Figure 6 The square shown, or formed as... Figure 7 The circle shown is not limited thereto.

[0054] exist Figures 4 to 7 In the figures, reference numerals 111, 112, and 113 represent grooves, reference numerals 121, 122, and 123 represent protrusions, S represents the width of the groove, S represents the space between the sides of adjacent protrusions, and W represents the length of the major axis of the protrusion, and W represents the maximum width of the protrusion.

[0055] Here, the length W of the major axis of the protrusion can be 40 μm or greater. Furthermore, the depth of the groove can be 2 μm or greater.

[0056] Next, a waterproof coating agent is applied to one surface of the lens portion 100 to form a waterproof layer (or waterproof coating), thereby forming the lens.

[0057] Here, the surface on which the waterproof layer is formed is the surface on which light is incident, and the waterproof coating agent can be a polymer-based material.

[0058] The waterproof layer can be formed by applying a waterproof coating agent to one surface of the lens portion 100 using an electron beam and thermal deposition process.

[0059] Here, the waterproof coating agent may include perfluoropolyether (PFPE), polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), perfluoroalkyl vinyl ether copolymer (PFA), polyvinyl fluoride (PVF), etc., which contain fluoropolymers.

[0060] Figure 8 This is a schematic cross-sectional view of a lens according to an exemplary embodiment of the present disclosure.

[0061] Reference Figure 8 and Figure 4 According to an exemplary embodiment, the lens 10 includes a lens portion 100 and a waterproof layer 600.

[0062] The lens portion 100 is not particularly limited in shape or type and can be implemented in a lens shape that can be used in optical devices such as camera modules.

[0063] Furthermore, the lens portion 100 can be formed of glass. However, the lens portion 100 can be formed of other materials, and can be formed of, for example, a plastic resin including a resin component.

[0064] For example, plastic resins may include at least one component of polycarbonate and polyolefin.

[0065] Here, polyolefins may include at least one of cyclic olefin polymers and cyclic olefin copolymers.

[0066] In an exemplary embodiment, the lens portion 100 has a protruding pattern having a plurality of protrusions 120 and a plurality of grooves 110 formed on its surface. Here, the grooves 110 refer to the gaps between the protrusions 120, i.e., spaces.

[0067] A waterproof layer 600 is disposed on one surface of the lens portion 100.

[0068] In addition, such as Figure 4 As shown, when the average area of ​​the groove 110 (i.e., per 1 mm of the lens portion 100) 2When the percentage of the area of ​​a surface without protrusions 120 is referred to as the space area ratio (%), in an exemplary embodiment, this space area ratio may be set to 20% or greater.

[0069] Here, the average area of ​​the groove 110 is obtained by generating an image of the surface of the lens portion 100 using SEM or TEM and excluding portions containing protrusions 120. The spatial area ratio, the length of the major axis of the protrusions, and the length between the longest portions of the grooves, etc., of such images are measured using image analysis software, as described below.

[0070] In this way, when the space area ratio is 20% or greater, the initial contact angle of the lens portion 100 can be achieved to be greater than 130°.

[0071] Furthermore, the height of each protrusion 120 in the lens portion 100 may be 2 μm or greater.

[0072] Furthermore, when the length of the major axis of the protrusion 120 in the lens portion 100 is referred to as the first length W and the length between the longest portions of the groove 110 is referred to as the second length S, the difference WS between the first length W and the second length S can be 20 μm or greater.

[0073] When the difference WS between the first length W and the second length S is 20 μm or greater, the lens 10 can ensure a transmittance close to that of the bare glass.

[0074] Here, the difference WS value can be obtained by measuring 10 or more values ​​and using their average.

[0075] On the other hand, non-destructive and destructive tests can be used to measure values ​​such as the thickness and length of the lens portion 100.

[0076] Examples of non-destructive testing include methods using ellipsometers, reflectometers, and atomic force microscopes.

[0077] As an example of destructive testing, the lens portion 100 can be subjected to focused ion beam (FIB) cross-section treatment, followed by analysis using transmission electron microscopy (TEM), and component analysis can also be performed using EDS. Furthermore, analysis can be performed using FT-IR, XPS, etc.

[0078] The cross-section of the protrusion 120 can be cut to include the central part of the lens portion 100, that is, the thickest area of ​​the lens portion 100.

[0079] Furthermore, the thickness of the protrusion 120 can be defined as a distance measured in a direction perpendicular to the surface of the protrusion 120, and can be determined as the average value of values ​​measured in a plurality of equally spaced regions.

[0080] In addition, the lens 10 may include an adhesive layer 500 disposed between the lens portion 100 and the waterproof layer 600 to prevent the waterproof layer 600 disposed on one surface of the lens portion 100 from being peeled off.

[0081] The adhesive layer 500 may be formed of one or more materials including SiO2, ZrO2, MgF2, Si3N4, Al2O3 and CeO2.

[0082] The adhesive layer 500 can be formed by applying processes such as sputtering, evaporation or chemical vapor deposition (CVD).

[0083] Figure 9 This is a schematic cross-sectional view of a lens according to another exemplary embodiment of the present disclosure.

[0084] Reference Figure 9 In another exemplary embodiment, the lens 10' may also include an anti-reflective (AR) coating portion 700 disposed between the lens portion 100 and the waterproof layer 600.

[0085] Here, the adhesive layer 500 is disposed between the AR coating portion 700 and the waterproof layer 600.

[0086] The AR coating portion 700 reduces the reflectivity of lens 10', thus reducing or preventing flare phenomena.

[0087] In addition, the AR coating portion 700 may include at least one material layer selected from the group consisting of siloxane, SiO2, SiON, Si3N4, TiO2, TiON and TiN.

[0088] As another example, the AR coating portion 700 may include a multilayer structure in which a first layer and a second layer with different refractive indices are alternately stacked once or multiple times.

[0089] In addition, the AR coating portion 700 may have a stacked structure in which the first layer is a SiO2 layer and the second layer is a TiO2 layer.

[0090] This AR coating portion 700 can be formed by coating a surface of the lens portion 100 using an electron beam process with an electron beam evaporator device having a heating element.

[0091] Figures 10 to 14 It is a graph showing how the contact angle of the lens varies with the spatial area ratio of the groove when the depth of the groove is different.

[0092] Figure 10The average depth of the groove is shown to be 0.5 μm, and here it can be seen that when the space area ratio is 40% or less, the contact angle is about 115°.

[0093] Figure 11 The average depth of the groove is shown to be 1.0 μm, and here the contact angle is 115° or greater, up to about 140°.

[0094] Figure 12 The average depth of the groove is shown to be 2.0 μm, and here the contact angle is 115° or greater, and when the space area ratio is 20% or greater, the contact angle is 130° or greater.

[0095] Figure 13 The average depth of the groove is shown to be 3.0 μm, and here the contact angle is 115° or greater, and when the space area ratio is 20% or greater, the contact angle is 130° or greater.

[0096] Figure 14 The average depth of the groove is shown to be 4.0 μm, and here the contact angle is 120° or greater, and when the space area ratio is 20% or greater, the contact angle is 130° or greater.

[0097] Reference Figures 10 to 14 The correlation between the space area ratio (%) per unit area and the initial contact angle of the lens based on the depth of the groove (etching depth) is as follows.

[0098] When the depth of the groove is less than 2 μm, the space area ratio (%) is not proportional to the contact angle.

[0099] However, when the groove depth is 2 μm, the space area ratio (%) and the contact angle are roughly proportional.

[0100] Furthermore, when the groove depth exceeds 2 μm, the space area ratio (%) and contact angle show almost no significant difference. Therefore, it can be seen that when the groove depth is deeper than 2 μm and the space area ratio (%) is 20% or greater, the contact angle is greater than 130°.

[0101] Figure 15 This illustrates the length of the lens according to the major axis of the protrusion and the dimensions described in this disclosure. Figure 8 A graph showing the transmittance value of the difference between the lengths of the longest portions of the grooves in the lens structure.

[0102] Reference Figure 15 It can be seen that when the difference WS between the length of the major axis of the protrusion and the length of the longest part of the groove is 20 μm or greater, the transmittance is close to that of the bare glass. The simulation tool used here is RSOFT. and LIGHTTOOLS results.

[0103] Lenses configured in this way can be applied to camera modules for electronic devices used in vehicles or for camera modules for portable electronic devices such as smartphones, tablets, PCs, and laptops used in IT.

[0104] In particular, since vision can be stably ensured even in wet conditions through camera lenses used in vehicle electronics, safe driving can be ensured when applied to fields such as autonomous driving.

[0105] In the case of a plane lens (hereinafter referred to as the “Comparative Example”) in which a waterproof coating is formed by simply applying a waterproof coating agent to the surface of the lens of the related technology, it may be difficult to make the initial contact angle greater than 120°.

[0106] Furthermore, in the case of the comparative example, as a result of the UV reliability assessment, it can be seen that the contact angle of the lens continues to decrease over time, and after 1500 hours, the contact angle of the lens decreases to below 90°, indicating that the waterproofness fails to be maintained for a long time.

[0107] On the other hand, in an exemplary embodiment, a waterproof coating is formed by applying a waterproof coating agent to the surface of the lens portion, and the surface of the lens portion is configured to have a protruding pattern including a plurality of protrusions, such that an initial contact angle of close to 140° of the lens can be obtained.

[0108] Here, by achieving a space area ratio of 20% or greater, the contact angle of the lens can remain greater than 130° even after 1750 hours, thus confirming that the lens has superhydrophobic properties.

[0109] In the case of a lens according to an exemplary embodiment of the present disclosure, a micropatterned protruding pattern can be formed on the surface, and a waterproof layer can be formed thereon, thereby enabling the lens to be superhydrophobic.

[0110] While specific examples have been shown and described above, it will be apparent upon understanding this disclosure that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered descriptive only and not for limiting purposes. The description of features or aspects in each example is to be applied to similar features or aspects in other examples. Suitable results may also be obtained if the described techniques are performed in a different order, and / or if components in the described system, architecture, device, or circuit are combined in a different manner and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents shall be construed as included in this disclosure.

Claims

1. A lens, comprising: The lens portion has a protruding pattern formed on the surface of the lens portion, the protruding pattern including a plurality of protrusions and a plurality of grooves; as well as A waterproof layer is provided on the surface of the lens portion. Wherein, every 1mm of the lens portion 2 When the percentage of the average area of ​​the grooves on the surface to the area of ​​the surface is referred to as the space area ratio, the space area ratio is 20% or greater.

2. The lens according to claim 1, wherein, The height of the protrusion in the lens portion is 2 μm or greater.

3. The lens according to claim 1, wherein, In the lens portion, when the length of the major axis of one of the plurality of protrusions is a first length and the length between the longest portions of one of the plurality of grooves is a second length, the difference between the first length and the second length is 20 μm or greater.

4. The lens according to claim 1, wherein, In the lens portion, the height of the protrusion is 2 μm or greater, and in the lens portion, when the length of the major axis of one of the protrusions is a first length and the length between the longest portions of one of the grooves is a second length, the difference between the first length and the second length is 20 μm or greater.

5. The lens according to claim 1, wherein, The protrusion is formed in a polygonal or circular shape.

6. The lens according to claim 1, wherein, It also includes an adhesive layer disposed between the lens portion and the waterproof layer.

7. The lens according to claim 1 further includes an anti-reflective coating portion disposed between the lens portion and the waterproof layer.

8. The lens according to claim 7 further includes an adhesive layer disposed between the anti-reflective coating portion and the waterproof layer.

9. The lens according to claim 7, wherein, The anti-reflective coating portion includes at least one material layer selected from the group consisting of siloxane, SiO2, SiON, Si3N4, TiO2, TiON and TiN.

10. The lens according to claim 7, wherein, The anti-reflective coating comprises a multilayer structure in which a first layer and a second layer with different refractive indices are alternately stacked once or multiple times.

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