A sapphire camera lens

Abstract

The utility model discloses a sapphire camera lens, this sapphire camera lens includes: the substrate layer, sapphire protection layer, silica transition layer and optical resin layer who sets up in order layering, wherein, sapphire protection layer, its outer surface has anti -reflection micro -nano structure, silica transition layer sets up in the inner surface of sapphire protection layer, optical resin layer sets up in the inner surface of silica transition layer, and its inner surface is aspherical optical curved surface. Sapphire camera lens realizes physical protection and optical performance decoupling through substrate layer-sapphire protection layer-silica transition layer-optical resin layer's order layering, separates and optimizes two big functions of superhard wear -resisting and precision imaging, the gradient transition of stress and optical parameter, inserts silica layer between hard brittle sapphire and pliable resin, forms the gradient buffer zone of hardness and thermal expansion coefficient, and the gentle transition of refractive index is realized simultaneously.

Description

Technical Field

[0001] This utility model relates to the field of camera lens technology, and in particular to a sapphire camera lens. Background Technology

[0002] With the increasing demands for image quality and durability from devices such as smartphones, action cameras, automotive cameras, and security monitoring systems, sapphire... Due to its extremely high surface hardness (Mohs hardness reaches 9), excellent wear resistance, and good chemical stability, it is widely used as the outer protective window for high-end camera lenses. Using sapphire lenses effectively prevents scratches during daily use and maintains optical clarity over long-term applications.

[0003] However, in practical applications, several inherent technical defects have been found in traditional single-structure sapphire protective lenses, limiting their application in scenarios with higher performance requirements: First, there are significant shortcomings in optical performance. The high refractive index of sapphire material itself (approximately 1.76) leads to significant Fresnel reflection loss on its surface, affecting image brightness and signal-to-noise ratio. Second, there are challenges in mechanical reliability. Sapphire is a hard and brittle material with low fracture toughness, making it prone to breakage due to stress concentration, especially at the lens edge or when subjected to lateral impacts. Third, there are severe constraints on the freedom of optical design. The extremely high hardness of sapphire crystals makes machining such complex optical surfaces extremely difficult, costly, and yield-prone. In addition, surface contamination and maintenance issues are also prominent. The smooth sapphire surface easily attracts fingerprints, oil, and water stains, affecting light transmittance and requiring frequent cleaning. Utility Model Content

[0004] Therefore, it is necessary to provide a sapphire camera lens to address the technical shortcomings of existing sapphire camera lenses in terms of optical performance and mechanical reliability.

[0005] A sapphire camera lens includes a substrate layer, a sapphire protective layer, a silicon dioxide transition layer, and an optical resin layer stacked sequentially. The sapphire protective layer has an anti-reflective micro / nano structure on its outer surface. The silicon dioxide transition layer is disposed on the inner surface of the sapphire protective layer. The optical resin layer is disposed on the inner surface of the silicon dioxide transition layer, and its inner surface is an aspherical optical surface.

[0006] In one embodiment, the aforementioned anti-reflective micro / nano structure is a biomimetic moth-eye structure periodically formed on the outer surface of the sapphire protective layer, the biomimetic moth-eye structure comprising multiple nanostructure units.

[0007] In one embodiment, the aforementioned nanostructure unit may be configured as either a nanocone or a nanopillar.

[0008] In one embodiment, the period of the aforementioned nanostructure unit is 150 nm to 250 nm, and the height is 200 nm to 400 nm.

[0009] In one embodiment, the inner surface of the optical resin layer described above is formed with a microlens array, each unit in the microlens array being an aspherical lens.

[0010] In one embodiment, the side edge region of the sapphire camera lens described above is integrated with a honeycomb microstructure support frame, which is formed by filling and curing a polymer material.

[0011] In one embodiment, the cell pore size of the aforementioned honeycomb microstructure support frame is 30 μm to 70 μm.

[0012] In one embodiment, the outer surface of the sapphire protective layer is further coated with a self-cleaning coating, which includes a photocatalytic material layer and a hydrophobic material layer.

[0013] In one embodiment, the thickness of the silicon dioxide transition layer is 40 nm to 60 nm, and the refractive index of the optical resin layer is 1.60 to 1.70.

[0014] In one embodiment, the optical resin layer described above is made of UV-cured optical-grade polyurethane acrylate.

[0015] In one embodiment, the edges of the aforementioned sapphire protective layer are curved microdome shapes.

[0016] The aforementioned sapphire camera lens achieves the following through sequential layering: substrate layer, sapphire protective layer, silicon dioxide transition layer, and optical resin layer. This decouples physical protection from optical performance, separating and optimizing the two major functions of ultra-hard wear resistance (sapphire layer) and precision imaging (resin aspherical layer), overcoming the bottleneck that a single material cannot simultaneously achieve both. Furthermore, the gradient transition of stress and optical parameters is achieved by inserting a silicon dioxide layer between the hard and brittle sapphire and the flexible resin, forming a gradient buffer zone for hardness and thermal expansion coefficient, while simultaneously achieving a smooth transition of refractive index. Specifically, the sapphire protective layer, as the outermost layer, retains the scratch and wear resistance of sapphire, providing long-term physical protection for the entire lens assembly. The anti-reflective micro-nano structure on the outer surface replaces the traditional multi-layer coating, achieving extremely low reflectivity over a wider spectral range and at a larger incident angle, significantly improving light transmittance. Furthermore, the anti-reflective micro-nano structure is directly etched onto the sapphire body, becoming an integral part of the substrate. This completely solves the problem of traditional coatings being prone to wear and peeling due to low hardness and weak adhesion, and its lifespan is consistent with that of the lens body. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a sapphire camera lens in one embodiment. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0019] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0022] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] Please see Figure 1 This invention discloses a sapphire camera lens, comprising a substrate layer 10, a sapphire protective layer 20, a silicon dioxide transition layer 30, and an optical resin layer 40 stacked sequentially. The sapphire protective layer 20 has an anti-reflective micro / nano structure 21 on its outer surface. The silicon dioxide transition layer 30 is disposed on the inner surface of the sapphire protective layer 20. The optical resin layer 40 is disposed on the inner surface of the silicon dioxide transition layer 30, and its inner surface is an aspherical optical surface. Based on the above configuration, this sapphire camera lens introduces the silicon dioxide transition layer 30 and the optical resin layer 40. The silicon dioxide layer acts as a stress buffer and refractive index transition interface, solving the problems of poor adhesion between sapphire and the resin layer and easy peeling due to mismatched thermal expansion coefficients. The outer sapphire protective layer 20 retains its strong physical protection function, while the inner resin layer provides the design of the optical surface with the freedom to correct aberrations, fundamentally improving image quality.

[0025] Furthermore, the anti-reflective micro / nano structure 21 is a biomimetic moth-eye structure periodically formed on the outer surface of the sapphire protective layer 20. The biomimetic moth-eye structure includes multiple nanostructure units 211. In some embodiments, the nanostructure units 211 can be configured as either nanocones or nanopillars. The biomimetic moth-eye structure is a subwavelength structure with an effective refractive index that gradually varies from air to the sapphire body. Compared to traditional multilayer dielectric films, it can achieve a wider spectral range (especially visible to near-infrared) and extremely low reflectivity at larger incident angles. Moreover, because it is directly etched onto the sapphire body, there is no risk of film wear and peeling, resulting in excellent durability.

[0026] Furthermore, the period of the nanostructure unit 211 is 150 nm to 250 nm, and the height is 200 nm to 400 nm. In practical applications, this size range achieves optimal broadband antireflection performance for commonly used imaging bands of 400 nm to 1000 nm. A period less than 150 nm significantly increases fabrication difficulty, while a period greater than 250 nm may enter the diffraction region, affecting imaging; a height within this range ensures sufficient effective refractive index gradient depth, achieving low reflectivity.

[0027] Furthermore, a microlens array 41 is formed on the inner surface of the optical resin layer 40, and each unit in the microlens array 41 is an aspherical lens. Concretizing the inner optical structure as an aspherical microlens array 41 allows the large-aperture imaging task to be decomposed into multiple sub-apertures for parallel processing. Combined with the aspherical design, it can more effectively correct spherical aberration, astigmatism, and field curvature caused by the high refractive index of sapphire and wide-angle incidence, significantly improving the sharpness and contrast of image edges, making it particularly suitable for large-aperture or wide-angle cameras.

[0028] Furthermore, a honeycomb microstructure support frame 50 is integrated into the side edge region of the sapphire camera lens. This honeycomb microstructure support frame 50 is formed by filling and curing a polymer material. The honeycomb microstructure applied to the lens edge can efficiently absorb and disperse impact energy from the sides, preventing stress concentration on the brittle sapphire edge and subsequent cracking. In some embodiments, the honeycomb microstructure support frame 50 is filled with a polymer (such as polyimide), ensuring both structural strength and providing good toughness buffering, thus significantly improving the lens's resistance to mechanical impact.

[0029] Furthermore, the pore size of the honeycomb microstructure support frame 50 is between 30 μm and 70 μm. This pore size range of the honeycomb microstructure allows for optimal stress dispersion and absorption balance within a limited edge width. If the pore size is too small, the structure tends to be solid, resulting in poor cushioning; if the pore size is too large, the support unit walls become too thin, leading to insufficient local strength. This size ensures maximum impact resistance without significantly increasing the overall size of the lens.

[0030] Furthermore, the outer surface of the sapphire protective layer 20 is also coated with a self-cleaning functional coating 22, which includes a photocatalytic material layer 221 and a hydrophobic material layer 222. The photocatalytic material layer 221 (such as titanium dioxide) can decompose organic stains under light; the hydrophobic material layer 222 (such as perfluorosilane) makes it difficult for water droplets to adhere, allowing them to roll off easily and carry away dust. The combination of the two achieves physical and chemical synergistic self-cleaning, greatly reducing contamination and maintenance needs on the lens surface, and ensuring long-term imaging clarity in harsh environments (such as rain, snow, and oily environments).

[0031] Furthermore, the thickness of the silicon dioxide transition layer 30 is 40 nm to 60 nm, and the refractive index of the optical resin layer 40 is 1.60 to 1.70. The thickness of the silicon dioxide transition layer 30 is designed to be on the order of optical wavelengths, serving a dual purpose of anti-reflection and stress matching; this thickness range achieves good interference anti-reflection effects. The refractive index of the optical resin layer 40 is between that of sapphire and air, and preferably close to the refractive index of other optical components inside the camera. This helps reduce the total interface reflection loss in the entire optical system and simplifies aberration correction.

[0032] Furthermore, the optical resin layer 40 is made of UV-curable optical-grade polyurethane acrylate. Polyurethane acrylate optical resins possess high light transmittance, low yellowing, excellent toughness and adhesion, and good UV curing properties. Using this type of material, it is easy to form high-precision aspherical or microlens arrays 41 on the silica transition layer 30 using precision processes such as UV nanoimprinting (UV-NL), ensuring mass production feasibility and consistency.

[0033] Furthermore, the edges of the sapphire protective layer 20 are curved micro-dome shapes. This claim optimizes the edge geometry of the sapphire layer. Replacing traditional right-angled or acute-angled edges with smooth "micro-dome" curved transitions eliminates stress concentration points at the edges. When subjected to external forces, stress can be smoothly distributed along the curved surface, preventing crack initiation and propagation from the edges, further enhancing the overall structural reliability and shatter resistance of the lens.

[0034] In summary, the sapphire camera lens disclosed in this invention achieves the following through the sequential stacking of a substrate layer, a sapphire protective layer, a silicon dioxide transition layer, and an optical resin layer: decoupling of physical protection and optical performance, separating and optimizing the two major functions of ultra-hard wear resistance (sapphire layer) and precision imaging (resin aspherical layer), breaking through the bottleneck that a single material cannot simultaneously achieve both; and a gradient transition of stress and optical parameters, by inserting a silicon dioxide layer between the hard and brittle sapphire and the flexible resin, forming a gradient buffer zone of hardness and thermal expansion coefficient, while simultaneously achieving a smooth transition of refractive index. Specifically, the sapphire protective layer, as the outermost layer, retains the scratch and wear resistance of sapphire, providing long-term physical protection for the entire lens assembly. The anti-reflective micro-nano structure on the outer surface replaces the traditional multi-layer coating, achieving extremely low reflectivity over a wider spectral range and at a larger incident angle, significantly improving light transmittance. Furthermore, the anti-reflective micro-nano structure is directly etched onto the sapphire body, becoming an integral part of the substrate. This completely solves the problem of traditional coatings being prone to wear and peeling due to low hardness and weak adhesion, and its lifespan is consistent with that of the lens body.

[0035] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0036] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A sapphire camera lens, characterized in that, include: A substrate layer, a sapphire protective layer, a silicon dioxide transition layer, and an optical resin layer are sequentially stacked. The sapphire protective layer has an anti-reflective micro / nano structure on its outer surface. The silicon dioxide transition layer is disposed on the inner surface of the sapphire protective layer. The optical resin layer is disposed on the inner surface of the silicon dioxide transition layer, and its inner surface is an aspherical optical surface.

2. The sapphire camera lens according to claim 1, characterized in that, The anti-reflective micro / nano structure is a biomimetic moth-eye structure periodically formed on the outer surface of the sapphire protective layer, and the biomimetic moth-eye structure includes multiple nanostructure units.

3. The sapphire camera lens according to claim 2, characterized in that, The nanostructure unit can be set as either a nanocone or a nanopillar.

4. The sapphire camera lens according to claim 3, characterized in that, The period of the nanostructure unit is 150nm to 250nm, and the height is 200nm to 400nm.

5. The sapphire camera lens according to claim 4, characterized in that, The inner surface of the optical resin layer is formed with a microlens array, and each unit in the microlens array is an aspherical lens.

6. The sapphire camera lens according to claim 5, characterized in that, The side edge region of the sapphire camera lens is integrated with a honeycomb microstructure support frame, which is formed by filling and curing a polymer material.

7. The sapphire camera lens according to claim 6, characterized in that, The cell pore size of the honeycomb microstructure support frame is 30 μm to 70 μm.

8. The sapphire camera lens according to claim 7, characterized in that, The outer surface of the sapphire protective layer is also covered with a self-cleaning coating, which includes a photocatalytic material layer and a hydrophobic material layer.

9. The sapphire camera lens according to claim 8, characterized in that, The thickness of the silicon dioxide transition layer is 40 nm to 60 nm, and the refractive index of the optical resin layer is 1.60 to 1.

70.

10. The sapphire camera lens according to claim 9, characterized in that, The optical resin layer is made of UV-cured optical-grade polyurethane acrylate.

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