Lens assembly

Abstract

This disclosure relates to a lens assembly. The lens assembly includes a lens barrel, a plurality of lenses disposed along an optical axis within the lens barrel, and spacers disposed between the plurality of lenses. The spacers include a plurality of grains and a plurality of pores. The plurality of grains include at least one selected from alumina (Al₂O₃), titanium dioxide (TiO₂), silicon dioxide (SiO₂), and zirconium oxide (ZrO₂).

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0198972, filed on December 27, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure relates to lens assemblies. Background Technology

[0004] Recently, camera modules have been used in portable electronic devices such as, but not limited to, smartphones.

[0005] A camera module may include a lens assembly with multiple lenses. To improve the performance of the camera module, the number of lenses included in the camera module is increased, and the overall size of the camera module is reduced.

[0006] It may be desirable for automotive camera modules to have high reliability so that they can operate without failure even under environmental changes such as varying weather conditions. In particular, condensation may occur in the lens of the camera module due to rapid temperature changes or high humidity environments, which could reduce the reliability of the camera module. Summary of the Invention

[0007] The summary portion of this invention is intended to provide a brief overview of the chosen concepts, which will be further described in the detailed description portion below. This summary portion 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.

[0008] In one general aspect, the lens assembly includes: a lens barrel; a plurality of lenses disposed along an optical axis within the lens barrel; and a spacer disposed between the lenses among the plurality of lenses, wherein the spacer includes a plurality of grains and a plurality of pores, wherein the plurality of grains include at least one of alumina (Al2O3), titanium dioxide (TiO2), silicon dioxide (SiO2), and zirconium oxide (ZrO2).

[0009] Multiple pores can be set between multiple grains.

[0010] The average diameter of multiple pores can be greater than 0 nm and less than or equal to 100 nm.

[0011] When the volume occupied by multiple pores is defined as Vp, and the volume of the spacer is defined as Vt, Vp / Vt can be greater than 0.2 and less than 0.65.

[0012] The spacer may include a first layer and a second layer disposed on the first layer in a direction perpendicular to the optical axis, wherein the average diameter of the plurality of grains in the first layer may be smaller than the average diameter of the plurality of grains in the second layer.

[0013] The first layer can be positioned closer to the surface of the spacer than the second layer.

[0014] The average diameter of multiple pores in the first layer can be smaller than the average diameter of multiple pores in the second layer.

[0015] The spacer may also include an intermediate layer disposed between the first layer and the second layer, wherein the average diameter of the plurality of grains in the intermediate layer may be greater than the average diameter of the plurality of grains in the first layer, and the average diameter of the plurality of grains in the intermediate layer may be less than the average diameter of the plurality of grains in the second layer.

[0016] The average diameter of multiple pores in the intermediate layer can be greater than the average diameter of multiple pores in the first layer, and the average diameter of multiple pores in the intermediate layer can be less than the average diameter of multiple pores in the second layer.

[0017] A coating may be provided on the surface of the spacer, and the coating may have at least one functional group selected from hydroxyl and amino.

[0018] The coating may include aminopropyltriethoxysilane (APTEOS).

[0019] In another general aspect, the lens assembly includes: a lens barrel; a plurality of lenses disposed in the lens barrel along an optical axis; and a spacer disposed between the lenses among the plurality of lenses, the spacer including a plurality of grains and a plurality of apertures, wherein the spacer includes a first layer and a second layer disposed on the first layer in a direction perpendicular to the optical axis, wherein the first layer is disposed closer to the surface of the spacer than the second layer, and wherein the average diameter of the plurality of apertures in the first layer is smaller than the average diameter of the plurality of apertures in the second layer.

[0020] The average diameter of multiple grains in the first layer can be smaller than the average diameter of multiple grains in the second layer.

[0021] A coating may be provided on the surface of the spacer, and the coating may have at least one functional group selected from hydroxyl and amino.

[0022] The coating may include aminopropyltriethoxysilane (APTEOS).

[0023] Other features and aspects will become apparent from the following detailed description and accompanying drawings. Attached Figure Description

[0024] Figure 1A schematic cross-sectional view of an exemplary lens assembly according to one or more embodiments is shown.

[0025] Figure 2 A spacer for an exemplary lens assembly according to one or more embodiments is shown.

[0026] Figure 3 It shows along Figure 2 The cross-sectional view taken from line I-I'.

[0027] Figure 4 It shows Figure 3 An enlarged view of part "A".

[0028] Figure 5 A cross-sectional view of a spacer in an exemplary lens assembly according to one or more embodiments is shown.

[0029] Figure 6A , Figure 6B and Figure 6C They are shown respectively Figure 5 The crystal structure of each layer in it.

[0030] Throughout the accompanying drawings and detailed embodiments, unless otherwise described, the same reference numerals refer to the same elements. For purposes of 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

[0031] The following detailed embodiments are provided to help the reader gain 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 become apparent upon understanding the disclosure of this application. For example, the order of operations described herein and / or the sequence of operations described herein are merely examples and are not limited to the order set forth herein, except for the order of operations and / or the order of operations which must occur in a specific sequence, but can be varied, as will become apparent upon understanding the disclosure of this application. As another example, the order of operations and / or the order of operations can be performed in parallel, except for the order of operations and / or at least a portion of the order of operations which must occur in a sequence (e.g., a specific sequence). Furthermore, for clarity and conciseness, descriptions of features known upon understanding the disclosure of this application may be omitted.

[0032] Although terms such as “first,” “second,” and “third,” or A, B, (a), (b), may be used herein to describe various components, parts, regions, layers, or sections, these components, parts, regions, layers, or sections are not limited by these terms. Each of these terms is not intended to define, for example, the importance, sequence, or order of the corresponding component, part, region, layer, or section, but only to distinguish the corresponding component, part, region, layer, or section from other components, parts, regions, layers, or sections. Therefore, without departing from the teachings of the examples described herein, the first component, first part, first region, first layer, or first section mentioned in these examples may also be referred to as the second component, second part, second region, second layer, or second section.

[0033] Throughout this specification, when a component, element, or layer is described as "on another component, element, or layer," "connected to," "attached to," or "joined to" another component, element, or layer, it may be directly "on another component, element, or layer," directly "connected to," "attached to," or "joined to" another component, element, or layer (e.g., in contact with another component, element, or layer), or one or more other components, elements, or layers may reasonably be present between that component, element, or layer and that other component, element, or layer. When a component, element, or layer is described as "directly on another component, element, or layer," "directly connected to," "directly attached to," or "directly joined to" another component, element, or layer, then there are no other components, elements, or layers between that component, element, or layer and that other component, element, or layer. Similarly, expressions such as "between" and "directly between," and "adjacent" and "directly adjacent" may also be interpreted as described above.

[0034] The terminology used herein is for describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the terms “a,” “an,” and “the” are intended to equally include the plural forms. As non-limiting examples, the terms “comprising,” “including,” and “having” indicate the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof, or alternatives to the stated features, quantities, operations, components, elements, and / or combinations thereof. Furthermore, while one embodiment may describe the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof using the terms “comprising,” “including,” and “having,” other embodiments may exist in which one or more of the stated features, quantities, operations, components, elements, and / or combinations thereof are absent.

[0035] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more items. Phrases such as “at least one of A, B, and C” are intended to have a disjunctive meaning, and these phrases also include examples in which one or more of A, B, and C may be present (e.g., any combination of one or more of A, B, and C), unless the corresponding description and implementation require that the enumeration (e.g., “at least one of A, B, and C”) be interpreted as having a conjunctive meaning.

[0036] The features described herein may be embodied in various forms and should not be construed as being 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, apparatus, and / or systems described herein will be apparent upon understanding the disclosure of this application. In this document, the use of the term “may” (e.g., regarding what an example or implementation may include or implement) with respect to an example or implementation means that there exists at least one example or implementation that includes or implements such a feature, and that all examples or implementations are not limited thereto. The terms “example” or “implementation” as used herein have the same meaning (e.g., the phrase “in one example” has the same meaning as “in one implementation,” and “in one or more examples” has the same meaning as “in one or more implementations”).

[0037] One or more embodiments may provide a lens assembly that prevents water vapor from condensing on the lens.

[0038] Figure 1 A schematic cross-sectional view of an exemplary lens assembly according to one or more embodiments is shown.

[0039] Reference Figure 1 According to one or more embodiments, the lens assembly 1 may include a lens barrel 2 and a plurality of lenses 3 disposed in the lens barrel 2. Spacers SP may be disposed between the lenses among the plurality of lenses 3.

[0040] Lens assembly 1 may include at least two lenses 3 disposed along the optical axis Z within lens barrel 2, and a spacer SP may be disposed between the at least two lenses 3. In this exemplary embodiment, for example, a structure including eight lenses is presented. However, this structure is merely an example, and lens assemblies including at least two lenses may be included within the scope of the exemplary embodiments.

[0041] The lens barrel 2 may have a hollow cylindrical shape to accommodate multiple lenses 3 that capture images of the object. The multiple lenses 3 may be mounted along the optical axis within the lens barrel 2. In this example, the lens barrel 2 may be formed of polycarbonate.

[0042] The lens assembly 1 according to an exemplary embodiment may include a spacer SP disposed between lenses 3. The spacer SP may be configured to maintain a constant interval between two adjacent lenses 3. In optical system design, the interval between lenses 3 can be a major factor affecting image quality, and the spacer SP can allow adjacent lenses among a plurality of lenses 3 to be spaced apart from each other by a predetermined interval.

[0043] Figure 2 This is a diagram illustrating a spacer SP of a lens assembly according to one or more embodiments. Figure 3 It is along Figure 2 The cross-sectional view taken from line I-I'.

[0044] Reference Figure 2 and Figure 3 The spacer SP can have an inner surface 10 forming an opening and an outer surface 20 opposite to the lens barrel 2. The inner surface 10 of the spacer SP can have an opening through which light passes. That is, the space surrounded by the inner surface 10 of the spacer SP body can define the opening. In the example, the inner surface 10 of the spacer SP, i.e., the inner wall formed around the center of the opening, can refer to a surface configured to face a direction perpendicular to the direction of light transmission (optical axis direction). That is, the inner surface 10 of the spacer SP can refer to the inner surface of the spacer SP body having an annular shape.

[0045] The spacer SP can be configured to block a portion of the light passing through one side of each of the multiple lenses 3. The spacer SP can prevent or minimize flare phenomena by blocking a portion of the light.

[0046] Figure 4 It shows Figure 3 An enlarged view of part "A".

[0047] Reference Figure 4The spacer SP may include multiple grains G and multiple pores P. The multiple grains G may include at least one of alumina (Al2O3), titanium dioxide (TiO2), silicon dioxide (SiO2), and zirconium oxide (ZrO2). In related technologies, the spacer may be formed of a metallic material (e.g., a non-ferrous metal material). For example, the spacer may be formed of phosphor bronze. The spacer SP of the lens assembly according to this exemplary embodiment may be formed of ceramic having a porous structure. That is, the lens assembly according to this exemplary embodiment may include a spacer SP formed of a porous hygroscopic material to prevent water vapor condensation in the lens assembly. The spacer SP formed of a porous hygroscopic material can exert a hygroscopic effect under rapid temperature changes or high humidity conditions caused by the external environment, thereby suppressing the condensation and dew phenomena of moisture appearing in the lens assembly. The spacer SP can be formed by mixing ceramic powder particles with a binder, solvent, etc., molding and drying the mixture to fix its shape, and then sintering it at a high temperature of 800°C or above.

[0048] Multiple pores P can be formed between multiple grains G. Multiple pores P can be formed in the portion of the spacer SP where the binder, etc., has been removed, and the average diameter of the multiple pores P can be greater than 0 nm and less than or equal to 100 nm. Multiple pores P can be formed at the nanoscale, allowing water molecules to be physically adsorbed into the nanoscale pores. Furthermore, water molecules can be effectively captured through capillary condensation mechanisms, etc. When the average diameter of the multiple pores P is greater than 100 nm, the surface area of ​​the pores may decrease, making it more likely that water molecules will evaporate or leak from the pores, which may reduce the hygroscopic performance of the spacer SP. However, one or more examples are not limited to this. As in the modified examples described below, the pore size can be greater than 100 nm depending on the layer formation of the spacer SP.

[0049] When the volume occupied by multiple pores P is defined as Vp and the volume of the spacer SP is defined as Vt, the porosity of the spacer SP material, i.e., (Vp / Vt)×100%, can be above 20% and below 65%. Vt can refer to the external volume of the material including the volume of the multiple pores P. When the porosity is less than 20%, the pore volume may be insufficient, thus limiting the amount of water molecules that can be absorbed, which may reduce the hygroscopic performance of the spacer SP. When the porosity of the spacer SP material is greater than 65%, the pore volume may increase excessively, leading to increased connectivity between pores, thereby reducing the structural stability and mechanical strength of the spacer SP.

[0050] The diameter of each of the plurality of pores P and the plurality of grains G according to this exemplary embodiment can be measured by analyzing high-magnification images obtained using a scanning electron microscope (SEM). The detailed method can be as follows: the sample with the porous ceramic structure can be cut into a cross-sectional shape and processed to a form suitable for SEM analysis; the Feret diameter, representing the maximum diameter of each pore and each grain, can be measured; the measurement can be performed using particle size analysis software, and an average value can be calculated based on the data obtained by measuring the Feret diameters of the plurality of pores and grains.

[0051] Bulk density (ρ) can be used bulk ) and true density (ρ true Porosity can be measured and calculated as follows: Equation 1: Porosity (%) = (1-ρ) bulk / ρ true )×100% Bulk density (ρ) bulk Bulk density (ρ) can refer to the ratio of the mass of a sample to its total volume. bulk It can be measured using the Archimedes method or the geometric method.

[0052] True density (ρ) true True density (ρ) can refer to the density of a material excluding pores. true The density can be measured using the helium specific gravity bottle method, or the standard density value of the material can be used.

[0053] The lens assembly according to this exemplary embodiment may include a coating C disposed on the surface of the spacer SP or on the surface of the lens barrel 2.

[0054] Reference Figure 3 The coating C can be applied to the inner surface of the spacer SP or the outer surface of the spacer SP.

[0055] Reference Figure 1 The coating C can be applied to the surface of the lens barrel 2. Specifically, the coating C can be applied to the inner surface of the lens barrel 2 on which the lens 3 is disposed.

[0056] Coating C may include at least one functional group selected from hydroxyl (-OH) and amino (-NH2). Hydroxyl and amino groups can enhance the hygroscopic properties of the spacer SP by interacting with water molecules. For example, coating C may include aminopropyltriethoxysilane (APTEOS). Aminopropyltriethoxysilane (APTEOS) may include amino and siloxane groups. The amino group can make the surface of the spacer SP (or lens barrel 2) hydrophilic, and the siloxane group can bind to the surface of the spacer SP (or lens barrel 2) to form a robust coating.

[0057] By way of example only, coatings can be formed to a thickness of 10 nm to 500 nm using processes such as atomic layer deposition (ALD), molecular vapor deposition (MVD), spraying, dipping, or UV treatment. Hydrophilic coatings containing specific functional groups can be applied to the surface of porous hygroscopic materials to improve the moisture absorption properties of spacers (SPs) and optimize moisture management in lens assemblies.

[0058] Figure 5 This is a cross-sectional view of a spacer in a lens assembly according to one or more modified examples of embodiments. Figure 6A , 6B And 6C shows Figure 5 The crystal structure of each layer is shown. Figure 6A , Figure 6B and Figure 6C The crystal structures of the first layer L1, the intermediate layer L3, and the second layer L2 are shown respectively.

[0059] Reference Figure 5 According to the modified example, the spacer SP can have multiple layers in the direction perpendicular to the optical axis. Specifically, the spacer SP can include a first layer L1, an intermediate layer L3, and a second layer L2, which can be arranged in the order of first layer L1, intermediate layer L3, and second layer L2 in the direction perpendicular to the optical axis. Each layer L1, L2, and L3 can respectively include multiple grains G1, G2, and G3, and multiple pores P1, P2, and P3 formed between the multiple grains.

[0060] In the following text, for ease of description, the plurality of grains G1 in the first layer L1 can be referred to as first grains G1, the plurality of grains G2 in the second layer L2 can be referred to as second grains G2, and the plurality of grains G3 in the intermediate layer L3 can be referred to as third grains G3. Similarly, the plurality of pores P1 formed between the first grains G1 can be referred to as first pores P1, the plurality of pores P2 formed between the second grains G2 can be referred to as second pores P2, and the plurality of pores P3 formed between the third grains G3 can be referred to as third pores P3.

[0061] The average diameter of the first grain G1 can be smaller than the average diameter of the second grain G2. The first layer L1 can be positioned closer to the inner or outer surface of the spacer SP than the second layer L2. That is, the spacer SP can include multiple layers with different grain sizes, and the first layer L1 with smaller grains can be positioned closer to the outer (or inner) surface of the spacer SP to improve moisture absorption performance. In addition, the second layer L2 with larger grains than the first grain G1 can be disposed in the spacer SP to provide structural strength and ensure mechanical support.

[0062] The average diameter of the first pore P1 can be smaller than the average diameter of the second pore P2. For example, the first pore P1 can have an average diameter greater than 0.05 μm and less than 1 μm, and the second pore P2 can have an average diameter greater than 5 μm. The first pore P1 can induce strong physical adsorption of water molecules, and the second pore P2 can promote the collection of a large amount of moisture.

[0063] The average diameter of the first pore P1 and the second pore P2 can be measured as follows. First, the sample with the porous ceramic structure can be cut into a cross-sectional shape and processed into a form suitable for SEM analysis. The first layer L1 can be positioned closer to the inner or outer surface of the spacer SP than the second layer L2, and thus a first and second point spaced apart from each other in a direction perpendicular to the optical axis Z can be selected to calculate the average diameter of the pores at each point. For example, the first point can correspond to a depth of 1 / 100 of the outer surface of the spacer SP, and the second point can correspond to a depth of 1 / 2 of the outer surface of the spacer SP. However, one or more examples are not limited to this.

[0064] Furthermore, each of the first and second points can refer to multiple points (e.g., five points) that are equally spaced apart from each other in a direction parallel to the optical axis Z in the cross-sectional sample. Therefore, the average value of the pore diameter can be calculated at each of the multiple first points and the multiple second points that are equally spaced apart from each other.

[0065] A similar method can be applied when measuring the average diameter of grains G1 and G2, and its detailed description is omitted here to avoid redundancy.

[0066] The intermediate layer L3 can be disposed between the first layer L1 and the second layer L2 of the spacer SP. The average diameter of the third grain G3 can be greater than the average diameter of the first grain G1 and smaller than the average diameter of the second grain G2. The grain diameter can gradually increase in the order of the first layer L1, the intermediate layer L3, and the second layer L2, thereby improving the bonding stability between layers and improving the thermal and mechanical shock resistance.

[0067] The average diameter of the third pore P3 can be greater than the average diameter of the first pore P1 and smaller than the average diameter of the second pore P2. In the example, the third pore P3 can have an average diameter greater than 1 μm and less than 5 μm. The third pore P3 can expand the path of material travel and prevent damage to the film.

[0068] While this disclosure includes specific examples, it will be apparent upon understanding the disclosure of this application 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 understood in a descriptive sense only and not for purposes of limitation. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Appropriate results may still be achieved 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.

[0069] Therefore, in addition to the above disclosure and all the accompanying drawings, the scope of this disclosure also includes the claims and their equivalents, that is, all variations within the scope of the claims and their equivalents should be understood to be included in this disclosure.

Claims

1. Lens assembly, including: Lens tube; Multiple lenses are arranged along the optical axis in the lens barrel; as well as Spacers are disposed between the lenses among the plurality of lenses. The spacer comprises multiple grains and multiple pores. The plurality of grains include at least one of aluminum oxide (Al2O3), titanium oxide (TiO2), silicon oxide (SiO2), and zirconium oxide (ZrO2).

2. The lens assembly according to claim 1, wherein, The plurality of pores are disposed between the plurality of grains.

3. The lens assembly according to claim 1, wherein, The average diameter of the plurality of pores is greater than 0 nm and less than or equal to 100 nm.

4. The lens assembly according to claim 1, wherein, When the volume occupied by the plurality of pores is defined as Vp, and the volume of the spacer is defined as Vt, Vp / Vt is greater than 0.2 and less than 0.

65.

5. The lens assembly according to claim 1, wherein, The spacer includes a first layer and a second layer disposed on the first layer in a direction perpendicular to the optical axis. The average diameter of the multiple grains in the first layer is smaller than the average diameter of the multiple grains in the second layer.

6. The lens assembly according to claim 5, wherein, The first layer is positioned closer to the surface of the spacer than the second layer.

7. The lens assembly according to claim 5, wherein, The average diameter of the multiple pores in the first layer is smaller than the average diameter of the multiple pores in the second layer.

8. The lens assembly according to claim 5, wherein, The spacer further includes an intermediate layer disposed between the first layer and the second layer. The average diameter of the multiple grains in the intermediate layer is greater than the average diameter of the multiple grains in the first layer, and The average diameter of the multiple grains in the intermediate layer is smaller than the average diameter of the multiple grains in the second layer.

9. The lens assembly according to claim 8, wherein, The average diameter of the multiple pores in the intermediate layer is greater than the average diameter of the multiple pores in the first layer, and The average diameter of the multiple pores in the intermediate layer is smaller than the average diameter of the multiple pores in the second layer.

10. The lens assembly according to claim 1, wherein, A coating is provided on the surface of the spacer, and The coating has at least one functional group selected from hydroxyl and amino groups.

11. The lens assembly according to claim 10, wherein, The coating comprises aminopropyltriethoxysilane.

12. A lens assembly, comprising: Lens tube; Multiple lenses are arranged along the optical axis in the lens barrel; as well as A spacer, disposed between the lenses among the plurality of lenses, the spacer comprising a plurality of grains and a plurality of apertures. The spacer includes a first layer and a second layer disposed on the first layer in a direction perpendicular to the optical axis. Wherein, the first layer is positioned closer to the surface of the spacer than the second layer, and The average diameter of the multiple pores in the first layer is smaller than the average diameter of the multiple pores in the second layer.

13. The lens assembly according to claim 12, wherein, The average diameter of the multiple grains in the first layer is smaller than the average diameter of the multiple grains in the second layer.

14. The lens assembly according to claim 12, wherein, A coating is provided on the surface of the spacer, and The coating has at least one functional group selected from hydroxyl and amino groups.

15. The lens assembly according to claim 14, wherein, The coating comprises aminopropyltriethoxysilane.

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