Optical lens

Abstract

The invention discloses an optical lens which sequentially comprises a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power and a fifth lens with focal power from the object side to the image side along the optical axis of the optical lens, and the fifth lens is a super lens. According to the present disclosure, by using the super lens, the miniaturization of the optical lens is facilitated, and the characteristic of small total length can be realized.

Description

TECHNICAL FIELD

[0001] The present application generally relates to the field of optical technology. More particularly, the present application relates to an optical lens. BACKGROUND

[0002] The development of current smartphone lenses has been highly mature. Due to the thickness limitation of smartphones, the total length limitation of the lenses has become one of the important influences on the imaging performance of the smartphone lenses, and also an important limitation on the appearance of the smartphones. At the same time, due to the size and material limitations of the smartphone lenses, there are certain difficulties in correcting chromatic aberration. SUMMARY

[0003] In order to at least solve one or more technical problems as mentioned above, the present application provides an optical lens, which comprises, in order from the object side to the image side along the optical axis of the optical lens: a first lens with positive refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with negative refractive power, and a fifth lens with refractive power, wherein the fifth lens is a superlens.

[0004] In some embodiments, the fifth lens is a superlens with the function of filtering specific wavelengths.

[0005] In some embodiments, the fifth lens comprises a substrate, and a microstructure and a filler formed on the substrate as a super surface, wherein the filler covers the microstructure and forms a filling plane, and a filter film for filtering specific wavelengths is coated on the filling plane.

[0006] In some embodiments, the super surface is arranged on the object side surface of the substrate.

[0007] In some embodiments, 0.168 < Lm / TTL < 0.225, wherein Lm is the distance along the optical axis from the super surface close to the object side to the imaging surface, and TTL is the total length of the optical lens.

[0008] In some embodiments, the height of the super surface is between 80-150 nanometers.

[0009] In some embodiments, -80 < f5 / f < 38.968, wherein f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical lens.

[0010] In some embodiments, 0.513 < TTL / IH < 0.701, wherein TTL is the total length of the optical lens, and IH is the diagonal length of the effective pixel area on the imaging surface of the optical lens.

[0011] In some embodiments, -38.57 <f2 / f<-4.004,其中f2为所述第二透镜的有效焦距,f为所述光学镜头的有效焦距。

[0012] In some embodiments, 1.81 <CT1 / CT2<2.82,其中CT1为所述第一透镜的中心厚度,CT2为所述第二透镜的中心厚度。

[0013] In some embodiments, 79.356° <FOV<93.649°, Wherein FOV is the maximum field of view of the optical lens.

[0014] In some embodiments, 0.109 <f1 / f3<0.595,其中f1为所述第一透镜的有效焦距,f3为所述第三透镜的有效焦距。

[0015] In some embodiments, 1.605 <f3 / f<9.33,其中f3为所述第三透镜的有效焦距,f为所述光学镜头的有效焦距。

[0016] In some embodiments, 1.79 <IH / f<2.2,其中IH为所述光学镜头的成像面上有效像素区域对角线长度,f为所述光学镜头的有效焦距。

[0017] A metalens is a two-dimensional, planar lens structure, typically only a few hundred microns thick, but can be manufactured down to nanometer thickness. It integrates the functionality of multiple curved lenses into a single device, significantly saving space compared to traditional lenses. The use of a metalens facilitates the miniaturization of optical devices, enabling a reduced overall length.

[0018] In addition, metalenses can be specially designed to correct chromatic aberration. For example, by adjusting the structural size, rotation angle or spatial arrangement of the metasurface subwavelength scattering unit, the incident light of different wavelengths can produce a phase distribution that meets the uniform focal length requirements, thereby correcting chromatic aberration. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an illustrative and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein: Figure 1 shows an exemplary structural diagram of an optical lens according to some embodiments of the present application; Figure 2 shows an exemplary structural diagram of the fifth lens in some embodiments of the present application; Figure 3Diffraction MTF curves of the optical lens of Embodiment 1 are shown; Figure 4 Diffraction MTF curves of the optical lens of Embodiment 2 are shown; Figure 5 Diffraction MTF curves of the optical lens of Embodiment 3 are shown; Figure 6 Diffraction MTF curves of the optical lens of Embodiment 4 are shown; Figure 7 Diffraction MTF curves of the optical lens of Embodiment 5 are shown; Figure 8 Diffraction MTF curves of the optical lens of Embodiment 6 are shown; Figure 9 Diffraction MTF curves of the optical lens of Embodiment 7 are shown; Figure 10 Diffraction MTF curves of the optical lens of Embodiment 8 are shown. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of, rather than all of, the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present disclosure.

[0021] It should be understood that the terms “comprising” and “including” used in the specification and claims of the present disclosure indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0022] It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "and / or," as used herein, refers to and encompasses any and all possible combinations of one or more of the associated listed items. It is also to be understood that the term "or" as used herein, refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0023] As used in this specification and claims, the terms "if' and "when" can each be interpreted to mean "upon determination" or "in response to a determination" or "upon detection" or "in response to a detection," depending on the context. Similarly, the phrase "if determined" or "if detected [the described condition or event]" can be interpreted to mean "upon determination" or "in response to a determination" or "upon detection" or "in response to a detection," depending on the context.

[0024] A detailed description of specific embodiments of the disclosure follows, in connection with the appended drawings.

[0025] In the drawings, the thickness, size, and shape of the lenses have been exaggerated slightly for the sake of explanation. Specifically, the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0026] Herein, the surface of each lens closest to the object to be imaged is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0027] Figure 1 An exemplary structural diagram of an optical lens of some embodiments of the present application is shown in FIG. 1. An optical lens of some embodiments of the present application sequentially includes, along an optical axis of the optical lens from an object side to an image side, a first lens L1 having positive refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a fourth lens L4 having negative refractive power, and a fifth lens L5 having refractive power, wherein the fifth lens is a superlens. Figure 1 An exemplary structural diagram of an optical lens of some embodiments of the present application is shown in FIG. 1. An optical lens of some embodiments of the present application sequentially includes, along an optical axis of the optical lens from an object side to an image side, a first lens L1 having positive refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a fourth lens L4 having negative refractive power, and a fifth lens L5 having refractive power, wherein the fifth lens is a superlens.

[0028] More specifically, S0 represents an object plane (the object plane is the plane in which the object to be imaged is located in the optical system, and is the starting source of light rays), S1 represents an aperture stop (the aperture stop is an element (or optical surface) in the optical system for limiting the size of the light beam, which can be a diaphragm with a hole, a lens frame, or a specially designed light transmission aperture), S2 represents the object side surface of the first lens L1, S3 represents the image side surface of the first lens L1, S4 represents the object side surface of the second lens L2, S5 represents the image side surface of the second lens L2, S6 represents the object side surface of the third lens L3, S7 represents the image side surface of the third lens L3, S8 represents the object side surface of the fourth lens L4, S9 represents the image side surface of the fourth lens L4, S10 represents the object side surface of the fifth lens L5 (the super surface of the super lens), S11 represents the image side surface of the fifth lens L5 (the base of the super lens), and S12 represents the imaging plane. The light from the object plane S0 passes through the surfaces S2 to S11 in sequence and is finally imaged on the imaging plane S12.

[0029] In some embodiments as mentioned later, S2-S9 are aspherical surfaces, and S11 is a spherical surface.

[0030] The super lens is a two-dimensional planar lens structure, usually only a few hundred microns thick, and can be made to a nanometer level of thickness. It can integrate the functions of multiple curved lenses into one device, greatly saving space compared to traditional lenses. By using a super lens, it is beneficial to realize the miniaturization of optical devices, and can achieve the characteristic of small total length.

[0031] In addition, the super lens can be specially designed to correct chromatic aberration. For example, by adjusting the structural size, rotation angle or spatial arrangement form of the subwavelength scattering units of the super surface, the phase distribution of different wavelength incident light that meets the unified focal length requirement can be generated, thereby correcting chromatic aberration.

[0032] In some embodiments, the fifth lens is a super lens with the function of filtering specific wavelengths. For example, the super lens is directly arranged on the filter. This design makes full use of the planar characteristics of the filter, because the super surface functional layer of the super lens needs to rely on the planar base to complete the processing and preparation of the nano structure, and integrating it on the functional surface of the filter, which is an indispensable core component in optical devices, not only does not need to introduce a new base, but also enables the super surface (such as realizing the functions of beam deflection, focusing or wavefront modulation) to form synergy with the filtering function, while ensuring the optical performance of the device, significantly simplifying the overall structure, and further realizing the characteristic of small total length.

[0033] The filter can accurately filter specific wavelengths in the incident light (for example, selectively transmitting visible light, cutting off infrared light or ultraviolet light, etc.).

[0034] Figure 2 Exemplary structural diagrams of the fifth lens of some embodiments of the present application are shown.

[0035] As Figure 2 described above, the fifth lens L5 includes a substrate 3, and a microstructure 2 and a filler 1 formed on the substrate as a super surface, wherein the filler 1 covers the microstructure 2 and forms a filling plane, and a filter film 4 for filtering specific wavelengths is plated on the filling plane.

[0036] The substrate 3 can be made of a resin material to form a resin substrate with an ultrathin characteristic, and the thickness of the resin substrate is designed to be less than 0.21 microns. This size breaks the lower limit of 0.21 microns generally adopted by traditional glass substrates due to considerations of breakage resistance and processing difficulty, and can significantly reduce the contribution of the substrate to the overall thickness of the device.

[0037] Specifically, the thickness of the resin substrate can be further optimized to 0.11 microns. This ultrathin size not only takes full advantage of the better flexibility and easy processing of the resin material itself (compared with glass, it is easier to achieve micron-level or even sub-micron-level ultrathin molding), but also can provide stable support for the filter plating layer and the super surface functional layer while minimizing the physical occupation of the substrate itself in the optical path, especially suitable for miniaturized optical modules (such as smart phone cameras, micro sensors, etc.) with strict thickness requirements, providing key support for the lightweight design of the overall structure.

[0038] The super surface functional layer adopts a mosaic structure layer of TiOx (titanium oxide, such as TiO2, Ti2O3, etc.) as the filler 1 and SiO2 (silicon dioxide) as the microstructure 2. That is, the two materials are combined in a periodic array or composite arrangement at the nanoscale, forming a functional structure with the characteristics of both.

[0039] Among them, TiOx has a high refractive index and good optical control ability, and can precisely modulate the phase, polarization state, etc. of incident light through the shape, size and distribution of its nanostructure; and SiO2 as a low refractive index material not only has excellent light transmission, but also provides a stable support framework for the TiOx structure, while the refractive index difference between the two materials enhances the interaction of the light field at the interface, improving the light manipulation efficiency of the super surface. This mosaic structure design not only plays a key role in TiOx in light modulation, but also optimizes the overall performance with the stability and optical compatibility of SiO2, so that the super surface functional layer can efficiently realize specific functions such as beam deflection, focusing, wavefront shaping, etc., and adapt to the ultrathin requirements of the integrated filter.

[0040] The refractive index of TiOx is in the range of 2.1 to 2.6, which is closely related to its chemical composition and preparation process.

[0041] From a material perspective, the ratio of titanium to oxygen (i.e., the stoichiometric ratio) in TiOx is crucial. For example, titanium dioxide (TiO2) typically has a higher refractive index (close to 2.6), while titanium dioxide (such as Ti2O3 and TiO) may have a refractive index in the range of 2.1-2.3 due to its lower oxygen content. Furthermore, the material's crystal structure (such as the rutile and anatase phases of TiO2) also affects the refractive index. The differences in atomic density between different crystal forms lead to different light propagation speeds within them, thus altering the refractive index.

[0042] Regarding the preparation temperature, during thin film deposition processes (such as magnetron sputtering and electron beam evaporation), temperature affects the crystallinity and density of TiOx. Higher deposition temperatures generally promote grain growth, resulting in a denser material structure and, consequently, a higher refractive index. Meanwhile, TiOx prepared at lower temperatures may have a relatively low refractive index due to fine grains or a high number of pores.

[0043] The refractive index of SiO2 (silicon dioxide) is related to its crystal structure, preparation process and the wavelength of the incident light. The common refractive index ranges in optical applications are as follows: Fused quartz (amorphous SiO2): In the visible light band (such as 550nm wavelength), the refractive index is approximately 1.458. It is one of the most commonly used SiO2 forms in the optical field. Due to its excellent light transmittance and stable refractive index, it is often used as an optical film, lens or substrate material.

[0044] Crystalline quartz (such as α-quartz): Due to its anisotropy, the refractive index in different crystal axis directions is slightly different, approximately 1.544 (ordinary light) and 1.553 (extraordinary light) in the visible light band.

[0045] In addition, the refractive index of SiO2 varies slightly with wavelength (dispersion characteristics). For example, in the ultraviolet band (200nm), the refractive index is about 1.50, and in the infrared band (1000nm), it drops to about 1.45, but the overall fluctuation is small. It is a low-refractive-index, high-stability optical material. This characteristic makes it often used as a support or spacer material in the functional layer of metasurfaces, forming a refractive index difference with the high-refractive-index TiOx, thereby enhancing the light field control effect.

[0046] Specifically, if Figure 2 As shown in the figure, the TiOx and SiO2 mosaic structure layer adopts an alternating arrangement design, that is, it is composed of TiOx parts and SiO2 parts alternately distributed in the horizontal direction. It is worth noting that in this alternating structure, each independent TiOx part and each independent SiO2 part is directly in contact with the underlying substrate. In other words, the nanostructure units of the two materials are not stacked in layers, but are arranged in an alternating manner in the same plane, and their bottoms form a direct physical connection with the substrate.

[0047] This design allows the high-refractive-index modulation characteristics of TiOx and the low-refractive-index support characteristics of SiO2 to be uniformly distributed within the same functional layer, while the direct contact of both with the substrate reduces light loss caused by intermediate interfaces and enhances the structural stability between the metasurface functional layer and the substrate.

[0048] In addition, as shown in Figure 2 , TiOx not only fills the gaps in the SiO2 framework but also extends and completely covers the top of the SiO2 part, ultimately forming a continuous and flat surface.

[0049] Specifically, Figure 2 , by increasing the deposition amount of TiOx, it continues to grow upwards after filling the gaps, completely covering the protruding part of SiO2, and ultimately eliminating the surface steps between the two materials.

[0050] The advantages of this design are: Optimization of optical performance: The flattened surface reduces scattering loss caused by interface concave-convex during light propagation, especially for optical paths that require low-loss transmission (such as laser beam modulation and precise imaging). Enhanced structural integrity: The TiOx covering layer "wraps" the dispersed SiO2 structure into a whole, improving the mechanical strength of the metasurface functional layer and reducing the risk of damage to local structures caused by external friction or stress. Improved compatibility: The flat surface is easier to integrate with other optical elements (such as filters and anti-reflection layers), reducing the risk of integration bubbles or optical interference caused by uneven interfaces.

[0051] This "filling and full coverage" design, while retaining the high-refractive-index modulation ability of TiOx and the low-refractive-index support of SiO2, further enhances the stability and integration of the device through planarization, making it suitable for scenarios with higher requirements for surface flatness and light transmission efficiency.

[0052] Coating a filter film 4 on the metasurface, i.e., the filter film is located on the same side of the metasurface and close to the incident light direction, has advantages in functional synergy efficiency, optical performance stability, and system integration.

[0053] I. Functional synergy: Early screening, reducing ineffective regulation of metasurfaces The filter film 4 directly faces the incident light, and can complete wavelength screening before the light enters the metasurface, allowing only light of the target wavelength to reach the metasurface microstructure. This means that the metasurface only needs to regulate the phase and amplitude of the "screened effective light", avoiding the generation of stray light, phase error or energy loss when irrelevant wavelengths (such as interference light) enter the metasurface due to mismatching of the microstructure design (such as the metasurface being optimized for a specific wavelength). For example, in fluorescence imaging, the filter film 4 first filters out the excitation light (to avoid its interference with the fluorescence signal), and the metasurface only needs to focus the fluorescence wavelength, resulting in higher efficiency and lower imaging noise.

[0054] II. Optical performance: reducing optical path loss and film layer interference The filter film and the metasurface are on the same side of the substrate, and the influence of the substrate thickness on the spectral performance of the filter film does not need to be considered (for example, the substrate material may absorb a specific wavelength, causing the actual effect of the filter film to deviate from the design).

[0055] III. System integration: more compact structure, suitable for miniaturization requirements The filter film and the metasurface are on the same side of the substrate, forming a "filter film-metasurface-substrate" stacked structure, and the overall thickness is only determined by the film layer + microstructure + substrate on one side, without the need for processing on both sides of the substrate, which is more conducive to reducing the axial size of the device. This design is particularly suitable for micro-optical systems that are sensitive to thickness (such as mobile phone lenses and endoscopes), which can reduce the space occupied during assembly.

[0056] In addition, according to some embodiments, the metasurface is arranged on the object side of the substrate. This design has clear functional orientation and performance optimization logic in the optical system. The object side is the side where the light first contacts in the optical system (i.e., the incident light enters the device from the object side), and the metasurface is arranged on this side, meaning that the metasurface can directly interact with the incident light and perform core optical regulation (such as phase modulation, focusing, beam shaping, etc.) at the front end of the optical path. The advantage of this "front-end regulation" is to avoid the loss that may occur when the light passes through the substrate first (such as absorption and scattering of the substrate material), ensuring that the metasurface can regulate the original incident light with high energy density, improving the efficiency of the optical function (such as the energy concentration of the focused spot).

[0057] In some embodiments, the height of the metasurface is between 80-150 nanometers.

[0058] The core of the metasurface is to regulate the phase, amplitude, etc. of light through subwavelength microstructures (with a size smaller than the wavelength of the incident light), and its height (i.e., the thickness of the microstructure and the filler, more specifically, the height of the microstructure in the case of a dielectric material as the filler, as shown in FIG. 1) is an important parameter that determines the performance of the metasurface. Figure 2In the described embodiment, the thickness of the filler 1 needs to form a reasonable proportion with the working wavelength (usually 1 / 5 to 1 / 2 of the wavelength). Taking the visible light band (400-700 nanometers) as an example, the height of 80-150 nanometers is exactly between 1 / 5-1 / 3 of this wavelength range. If the height is too small (such as less than 80 nanometers), the modulation depth of the microstructure to light is insufficient, and it is difficult to achieve complete 2π phase coverage (the basis for super surface to control light phase), which will lead to the decline of the efficiency of focusing, imaging and other functions.

[0059] If the height is too large (such as more than 150 nanometers), it may exceed the "sub-wavelength" category, causing high-order diffraction or mode interference, which will destroy the precise control of light, and at the same time increase the material absorption loss (especially for high refractive index dielectric materials).

[0060] For the near-infrared band (such as 900-1500 nanometers), this height range is also 1 / 10-1 / 6 of the wavelength, which can meet the low-loss control requirements.

[0061] In addition, the preparation of the microstructure and the filler of the super surface depends on high-precision micro-nano processing technology (such as electron beam lithography, nano-imprinting), and the height range of 80-150 nanometers is in the efficient controllable interval of the existing process.

[0062] If the height is too high (such as more than 200 nanometers), the photoresist layer thickness may not be uniform during the lithography process, and the development may not be complete, resulting in deviations in the microstructure morphology.

[0063] If the height is too low (such as less than 50 nanometers), the etching precision is required to be extremely high (nanometer-level error needs to be controlled), which is easy to cause inconsistent microstructure sizes due to process fluctuations, affecting the consistency of optical performance. This height range balances the processing precision and production efficiency, facilitating large-area, batch manufacturing, and reducing costs.

[0064] In summary, limiting the height of the super surface (the thickness of the filler 1) to 80-150 nanometers is an optimized choice that takes into account the optical control efficiency, process feasibility, and other factors, providing a reliable parameter basis for the practical application of super surfaces in imaging, sensing, optical communication, and other fields.

[0065] In some embodiments, 0.168 < Lm / TTL < 0.225, where Lm is the distance along the optical axis from the super surface close to the object side to the imaging surface, and TTL is the total length of the optical lens.

[0066] As the distance from the metasurface to the imaging plane, Lm directly determines the propagation path length of the light beam modulated by the metasurface before reaching the imaging plane. For the metasurface, its functions such as focusing and imaging need to be matched with a specific "modulation distance". If Lm is too short (the proportion is too small), the wavefront modulated by the metasurface has not fully formed a stable spot before reaching the imaging plane, which may cause image quality blur (such as spot diffusion); if Lm is too long (the proportion is too large), it will compress the layout space of other optical elements, resulting in an increase in the total length TTL of the lens, which violates the miniaturization design goal.

[0067] The rationality of the proportion range: the interval of 0.168-0.225 means that Lm accounts for about 1 / 6 to 1 / 4 of TTL, which not only reserves enough wavefront modulation distance for the metasurface (ensures that the light beam can be stably imaged after modulation), but also avoids the redundancy of TTL caused by too large Lm, and balances the optical performance and structural compactness. For example, in a lens with a total length of 10 mm, Lm is about 1.68-2.25 mm, and the metasurface can efficiently focus light rays in this range while leaving installation space for subsequent other components.

[0068] The phase modulation accuracy of the metasurface (such as whether it can achieve complete 2π phase coverage) is closely related to the distance from the metasurface to the imaging plane.

[0069] If Lm / TTL is too small (such as <0.168), the metasurface needs to converge the light beam in a very short distance, which may require the microstructure to have a stronger phase gradient, resulting in a sharp increase in processing difficulty and easy introduction of high-order aberrations (such as spherical aberration and coma); If Lm / TTL is too large (such as >0.225), the light beam may be divergent due to diffraction effects during propagation, or be disturbed by stray light inside the lens, thereby reducing the modulation efficiency of the metasurface. This proportion range ensures that the phase design (such as focal length and field angle) of the metasurface can be accurately matched with the position of the imaging plane by limiting the relative relationship between Lm and TTL, reducing the aberration compensation pressure, and is especially suitable for simplified lens design (such as a structure containing only a metasurface and a small number of auxiliary lenses) with the metasurface as the core imaging element.

[0070] In summary, the proportion limit of 0.168

[0071] According to some embodiments, -80

[0072] The core significance lies in achieving precise correction of chromatic aberration by adjusting the focal length ratio of the fifth lens (super lens) to the entire lens system.

[0073] The essence of chromatic aberration is that different wavelengths of light have different refractive indices in the lens, resulting in a deviation in the focusing position (e.g., the focal length of red light is different from that of blue light). As the fifth lens, the ratio of its focal length f5 to the total focal length f (f5 / f) directly determines its "regulation weight" in chromatic aberration correction.

[0074] When f5 is positive, the fifth lens has positive focal length (converging lens), and its chromatic dispersion characteristics (e.g., stronger convergence ability for short-wavelength light) can be designed to compensate for the excessive divergence (or insufficient) of other lenses in the system for short-wavelength light. When f5 is negative, the fifth lens has negative focal length (diverging lens), and its chromatic dispersion characteristics can be used to offset the excessive convergence of other lenses in the system for long-wavelength light, balancing the focusing positions of different wavelengths. This range (-80 to 38.968) covers a large interval of positive and negative focal lengths, providing a flexible "correction margin" for the superlens, which can adapt to the chromatic aberration distribution of different optical systems (e.g., different degrees of aberration for different wavelengths).

[0075] The upper limit 38.968 means that f5 / f < 38.968 implies that the focal length of the fifth lens will not be much larger than the total focal length of the system. If f5 is too large (the proportion exceeds the upper limit), the convergence / divergence ability of the superlens will be too strong, which may cause excessive regulation of specific wavelengths, introducing new aberrations (e.g., monochromatic aberrations), or imbalance with the light path of other lenses (e.g., a sudden change in the angle of the light beam before and after the superlens). Limiting the upper limit ensures that the correction effect of the superlens is within a "controllable range" and avoids interference with the overall optical performance of the system.

[0076] The lower limit -80 means that f5 / f > -80 (i.e., the absolute value of f5 does not exceed 80 times the focal length of the system) avoids excessive divergence (excessive negative focal length) of the superlens. If f5 is too negative (the proportion is lower than the lower limit), the divergence effect of the superlens will be too strong, which will significantly increase the "compensation burden" of other lenses (e.g., the need for stronger converging lenses to offset the divergence), leading to an increase in the total length of the system or a decrease in imaging efficiency. At the same time, excessive divergence may exacerbate the separation of different wavelengths of light, thereby worsening chromatic aberration.

[0077] The unique advantage of the superlens over traditional lenses is that its chromatic dispersion characteristics (the variation of focal length for different wavelengths) can be flexibly regulated through micro-nano structure design (e.g., adjusting the size of the nano pillars, the material refractive index dispersion). By limiting f5 / f within the above range, the chromatic dispersion characteristics of the superlens can form a "complementary relationship" with the overall dispersion of the system.

[0078] For example, if other lenses in the system have a shorter focal length for blue light than for red light (positive chromatic aberration), the fifth lens can be designed with a negative focal length (f5 is negative) and a weaker divergence for blue light than for red light (i.e., the blue light diverges less after passing through the superlens, equivalent to "zooming in" on the blue light focal length), thereby offsetting the positive chromatic aberration of the system. If the system has negative chromatic aberration (the focal length for red light is shorter than for blue light), the fifth lens with a positive focal length (f5 is positive) can be used to fine-tune the convergence of red light, achieving balance.

[0079] This range provides sufficient parameter space for such "complementary design" to enable the superlens to accurately match the type (positive / negative) and degree of chromatic aberration of the system, ultimately achieving the optimal effect of chromatic aberration correction (e.g., the focal points of different wavelengths overlap to the highest degree, and the imaging clarity is optimal).

[0080] This range also takes into account the characteristics of the superlens as a "thin component": if the ratio of f5 to f is too extreme (e.g., f5 is much larger than f), the superlens may need to be larger in size or have a more complex microstructure to achieve the corresponding focal length, which goes against its "miniaturization" advantage. The range of -80 to 38.968 ensures that the superlens can perform chromatic aberration correction while maintaining its thinness, and is compatible with the compact design of the system.

[0081] In summary, the range of -80 < f5 / f < 38.968 essentially achieves precise compensation for the chromatic aberration of the system by constraining the focal length ratio of the fifth lens (superlens) to the system, combined with the adjustable dispersion of the superlens, and is an optimized choice that balances correction effect, system compatibility, and miniaturization.

[0082] In some embodiments, 0.513 < TTL / IH < 0.701, where TTL is the total length of the optical lens, and IH is the diagonal length of the effective pixel area on the imaging surface of the optical lens.

[0083] The physical meaning of IH is the diagonal length of the effective pixel area on the imaging surface, which directly reflects the imaging range (related parameter of field of view size) that the lens needs to cover. For example, the larger the IH, the larger the imaging surface size, and theoretically, a longer lens focal length or a more complex optical path is needed to cover the full field of view.

[0084] The significance of the ratio constraint TTL / IH: This ratio is less than 0.701, indicating that the total length of the lens is significantly smaller than the diagonal length of the imaging surface, breaking the traditional correlation that "the larger the imaging surface, the longer the lens"; while greater than 0.513 ensures that the lens length is not excessively compressed (avoiding the inability to correct aberrations due to a too short optical path). For example, if IH is 10 mm (corresponding to a medium-sized imaging surface), TTL is limited to between 5.13 and 7.01 mm, and the total length of the lens is only half more than the diagonal of the imaging surface, achieving a compact design of "short total length covering a large imaging surface".

[0085] In traditional optical systems, the TTL / IH ratio is often greater than 1 (the total length of the lens exceeds the diagonal of the imaging surface), because traditional lenses need a certain distance to correct aberrations and achieve clear imaging. However, this ratio limits the TTL to 0.5-0.7 times the IH, and by optimizing the optical structure (such as using superlenses, aspherical lenses, and other high-efficiency elements) to reduce optical redundancy, the total length can be shortened without sacrificing the imaging range. The subwavelength control capability of superlenses can complete phase correction in a short distance, avoiding the dependence on "long optical path" of traditional lenses, which provides the possibility for compressing TTL.

[0086] For consumer electronics (such as mobile phones, tablets), wearable devices (such as AR glasses), and other scenarios sensitive to "thinness", the imaging surface size (IH) is often determined by functional requirements (such as high pixel requiring larger sensors), and the TTL / IH limit can ensure that the lens does not become "fixed and long" due to the increase in IH, thereby controlling the overall thickness and achieving system-level miniaturization.

[0087] For example, when the IH (imaging surface diagonal length) changes, the TTL (total length of the lens) needs to be adjusted synchronously according to the proportional range (0.513 < TTL / IH < 0.701), that is, the TTL value range should be scaled proportionally with IH, rather than a fixed interval. If IH = 8mm, according to the proportional range, the reasonable interval of TTL is: 8mm x 0.513 ≈ 4.104mm (lower limit), 8mm x 0.701 ≈ 5.608mm (upper limit); if IH increases to 10mm (imaging area expands), the reasonable interval of TTL synchronously changes to: 10mm x 0.513 ≈ 5.13mm (lower limit), 10mm x 0.701 ≈ 7.01mm (upper limit).

[0088] At this time, it can be seen that IH increases from 8mm to 10mm (25% increase), the lower limit of TTL increases from 4.104mm to 5.13mm (about 25% increase), and the upper limit increases from 5.608mm to 7.01mm (about 25% increase), with consistent increase amplitude.

[0089] The setting of the lower limit of the proportion 0.513 is to prevent the TTL from being excessively shortened and affecting the imaging quality.

[0090] If TTL / IH < 0.513, the total length of the lens is too short, and the arrangement space of each element (such as each lens) in the optical path is extremely compressed, which may lead to: Insufficient aberration correction (such as difficulty in balancing spherical aberration and coma in a short distance); Too large beam incidence angle (exceeding the receiving range of the imaging surface), leading to edge field image quality degradation; Too close distance between elements causing stray light (such as mutual interference of lens reflection light).

[0091] And the interval of 0.513-0.701, while compressing TTL, reserves enough "regulation space" for optical elements (such as the phase modulation distance of the superlens and the light path matching length of the filter film), ensuring that the light in the full field of view of the imaging surface can be effectively regulated, balancing miniaturization and imaging performance.

[0092] In summary, the ratio limit of 0.513<TTL / IH<0.701, by constraining the relative relationship between the total length of the lens and the size of the imaging surface, maximizes the compression of the optical path space while ensuring imaging quality, is a "precise size control" design for miniaturization of optical systems, and is especially suitable for consumer electronics, portable devices and other fields that are sensitive to volume and need to ensure imaging area.

[0093] In some embodiments, -38.57

[0094] By clearly defining the ratio relationship between the second lens (negative focal length lens) and the total focal length of the system, key optical design support is provided for lens miniaturization. The effective focal length f2 of the second lens is negative, indicating that it is a diverging lens, and its main function is to adjust the propagation direction of the light path by diverging the incident light beam, thereby reducing the arrangement space required for subsequent optical elements (such as subsequent lenses and imaging surfaces).

[0095] In an optical system, a diverging lens (negative focal length) can form a "combined light path" with the converging lenses (positive focal length) in the front / back section. For example, the incident light is first focused by the front converging lens, and then moderately diverged by the second lens (negative focal length), causing the "converging point" of the light beam to move backward or the light path angle to slow down, thereby shortening the distance from the second lens to the imaging surface without sacrificing imaging quality, ultimately compressing the total length (TTL) of the entire lens, creating conditions for miniaturization.

[0096] The lower limit -38.57 means to avoid excessive divergence. f2 / f>-38.57 means that the divergence ability of the second lens will not be too strong (the absolute value of f2 will not exceed 38.57 times the focal length f of the system). If f2 is too negative (the ratio is lower than the lower limit), the divergence effect of the lens on the light beam will be too strong, which will force the subsequent lens to have extremely strong converging ability to offset its divergence effect. This will force the curvature radius of the subsequent lens to become smaller and the thickness to increase, thereby increasing the system volume; at the same time, excessive divergence may cause the edge angle of the light beam to be too large, exceeding the receiving range of the imaging surface, causing the edge field of view to decay.

[0097] The upper limit -4.004 ensures sufficient divergent contribution. f2 / f <-4.004 ensures that the second lens has a certain divergent power (the absolute value of f2 is at least 4.004 times the focal length f of the system). If the absolute value of f2 is too small (the ratio is close to 0), its divergent effect is weak and cannot effectively adjust the optical path, making it difficult to shorten the TTL, and the problem of “long optical path” in traditional lens systems will still exist, which violates the miniaturization design goal. The core of miniaturization is to reduce the TTL while ensuring imaging performance, and the negative focal length ratio of the second lens is the key to achieving this goal: For devices such as mobile phones and miniature cameras that are sensitive to volume, the total focal length f of the system is usually short (such as a few millimeters), and at this time f2 of the second lens needs to be a more negative value (such as f = 10 mm, f2 needs to be between -40.04 mm and -385.7 mm). This strong divergent feature can significantly “pull apart” the propagation angle of the light beam, allowing the subsequent lenses to focus the light beam onto the imaging surface without the need for a long distance, thereby directly shortening the TTL.

[0098] Compared to the long optical path caused by the “step-by-step focusing” of multiple positive lenses in traditional designs, the introduction of the negative focal length ratio of the second lens allows the optical path to be more “compact” in completing the conversion from incidence to imaging, and does not sacrifice the field of view or resolution due to excessive compression.

[0099] In addition, although the second lens is a divergent lens, the limitation of its focal length ratio also indirectly assists in aberration correction: excessive divergence (too low a ratio) will introduce severe distortion or coma, while insufficient divergence (too high a ratio) will not alleviate the spherical aberration of the system. The range of -38.57 to -4.004 allows the second lens and other lenses to complement each other in terms of aberration, ensuring that while the TTL is compressed, the imaging quality (such as sharpness and distortion control) still meets the practical needs of the camera.

[0100] In summary, the limitation of -38.57 < f2 / f < -4.004, by precisely controlling the divergence of the second lens and the ratio of the total focal length of the system, balances the imaging performance and system compatibility while effectively shortening the optical path and compressing the total length of the lens, which is an important optical design method for miniaturizing the lens.

[0101] In some embodiments, 1.81 < CT1 / CT2 < 2.82, where CT1 is the central thickness of the first lens and CT2 is the central thickness of the second lens.

[0102] In optical design, the central thickness (CT) refers to the thickness of the thickest part of the lens along the optical axis, i.e., the thickness of the center of the lens (the point through which the optical axis passes).

[0103] Specifically, for a convex lens (thick in the middle, thin at the edges), the center thickness is the thickest part of the lens, which is the vertical distance from the front surface of the lens (close to the object side) to the back surface (close to the image side) along the optical axis; for a concave lens (thin in the middle, thick at the edges), the center thickness is the thinnest part of the lens, which is also the distance between the front and back surfaces measured along the optical axis; for a flat lens (such as a flat glass), the center thickness is equal to its uniform thickness.

[0104] By optimizing the thickness ratio of the first two lenses, the lens thickness is reasonably distributed under the premise of ensuring optical performance, providing key support for lens miniaturization.

[0105] The first lens and the second lens are front-end elements of the optical system, and their thickness designs need to match their respective optical functions.

[0106] The first lens usually undertakes the role of preliminary convergence or guiding incident light (especially close to the object side), and needs to have a certain thickness to ensure sufficient structural strength and optical regulation ability (such as the feasibility of processing curved surfaces, the material's light transmission efficiency), so CT1 needs to maintain a reasonable value. The second lens is a negative focal length lens (as described earlier), and its core function is to compress the subsequent space by diverging the light path, so an excessively thick design will directly increase the volume of the front section of the lens, which is not conducive to miniaturization, so the thickness of CT2 needs to be controlled.

[0107] This ratio range (1.81-2.82) clearly indicates that CT1 is about 1.8-2.8 times the thickness of CT2, which not only ensures that the first lens has sufficient thickness to complete the front-end optical regulation, but also reduces the space occupied by the front-end elements by limiting the relative thickness of CT2 (making it significantly thinner than CT1), achieving the effect of "function not reduced, volume compressed".

[0108] If CT1 / CT2>2.82, it means that the thickness of the first lens is much thicker than the second lens, which will lead to: the front end of the lens is too large (the thickness of the first lens as a front-end element directly affects the axial length and radial size of the lens); the amount of material increases, not only increasing the weight, but also possibly introducing additional aberrations due to excessive thickness (such as dispersion deviation caused by material unevenness). Limiting the upper limit can prevent the thickness of the first lens from being redundant, ensuring that its thickness only meets the functional requirements and does not occupy additional space. If CT1 / CT2<1.81, there are two cases: CT2 is too thick: increasing the thickness of the second lens will directly increase the total thickness of the front end, which will offset its role of "diverging the light path to compress the space", which violates the goal of miniaturization; CT1 is too thin: insufficient thickness of the first lens may affect its structural stability (such as being easily deformed by external forces) or optical performance (such as aberrations caused by insufficient precision of curved surface processing). Limiting the lower limit can ensure that CT2 maintains a relatively thin state, while ensuring that CT1 has sufficient thickness to support the front-end optical function.

[0109] The miniaturization of the lens not only requires the total length (TTL) to be shortened, but also requires the radial and axial dimensions of each element to be controlled. The first and second lenses, as the starting point of the optical path, directly affect the "front volume" of the lens.

[0110] If CT2 is relatively thicker than CT1 (the ratio is less than 1.81), the total thickness of the front end (CT1+CT2) will increase, resulting in the lens becoming thicker or longer overall.

[0111] If CT1 is excessively thick (the ratio is greater than 2.82), it will occupy more axial space, conflicting with the goal of shortening the TTL.

[0112] The ratio of 1.81-2.82 controls the total thickness (CT1+CT2) of the two lenses to be within a reasonable range, while ensuring the optical function of the front end, and reserving more layout space for subsequent elements (such as super lenses, imaging surfaces), ultimately achieving the miniaturization of the entire machine. For example, if CT2 is 1 mm, CT1 is controlled within 1.81-2.82 mm, and the total thickness of the two pieces is about 2.81-3.82 mm. Compared with the unbalanced design of "CT1=4 mm, CT2=1 mm" (total thickness of 5 mm), the front end thickness can be reduced by about 24%-44%.

[0113] For example, compared with the unbalanced design of CT1 / CT2=4, the total thickness reduction ratio is: (5mm-3.82mm) / 5mm≈23.6% (close to 24%); (5mm-2.81mm) / 5mm≈43.8% (close to 44%).

[0114] In addition, this ratio range also adapts to the processing technology of the lens.

[0115] The first lens has a moderate thickness (CT1 is thicker than CT2), which facilitates the implementation of processes such as curved surface grinding and coating, and ensures optical precision.

[0116] The second lens is relatively thin (CT2 is small), but it is not excessively thin due to the ratio limit, and still maintains processing feasibility (such as avoiding clamping deformation caused by excessive thinness).

[0117] At the same time, reasonable thickness distribution can reduce the impact of temperature changes on the lens (such as optical performance fluctuations caused by material thermal expansion and contraction), ensuring that the lens can still work stably under miniaturization design.

[0118] In summary, the limitation of 1.81<CT1 / CT2<2.82 precisely controls the thickness ratio of the first two lenses, balances the optical function, structural stability, and processing feasibility, and maximizes the compression of the space occupied by the front-end elements, which is an important detail design for the miniaturization of the lens.

[0119] In some embodiments, 79.356° < FOV < 93.649°, wherein FOV is the maximum field of view of the optical lens.

[0120] The maximum field of view (FOV) refers to the angle of the maximum spatial range that the optical lens can capture, usually represented by the sum of the maximum angles extending to both sides with the lens optical axis as the center.

[0121] Specifically, it is twice the angle between the most marginal light that the lens can image and the optical axis (i.e., the "full field of view"). For example, if the maximum imaging angle on the left side of the lens optical axis is 45° and the right side is also 45°, the maximum field of view is 90°.

[0122] The maximum field of view (FOV) determines the spatial range that the lens can capture. The larger the FOV, the more extensive the scene that the lens can shoot (such as landscapes, group photos). The range of 79.356°-93.649° belongs to the medium wide-angle interval, which not only meets the daily shooting demand for "large scene coverage" (compared to the standard lens FOV of about 50°, it can include more environmental information), but also avoids the imaging distortion problem common in ultra-wide-angle lenses (FOV>100°).

[0123] Specifically, if FOV≤79.356°, the field of view is too narrow, making it difficult to capture the target scene completely when shooting in a small space (such as indoors or in a car), limiting the applicable scenarios of the lens.

[0124] If FOV≥93.649°, although the shooting range can be further expanded, the angle of incidence of the light at the edge of the field of view increases, which can easily lead to increased aberrations (such as distortion, coma), and the edges of the image may appear blurred, stretched, or color shifted, affecting the consistency of the image.

[0125] This field of view range is highly adaptable to the miniaturization requirements of the lens.

[0126] Wide-angle lenses usually require more complex optical structures (such as multiple lens combinations) to correct aberrations, but if the FOV is excessively increased (such as more than 93.649°), to control the edge aberrations, the number of lenses or the size of the lenses needs to be increased, resulting in an increase in the total length (TTL) of the lens, which violates the miniaturization goal. The medium wide-angle interval of 79.356°-93.649° can achieve aberration correction with fewer lens numbers by optimizing lens curvature and introducing high-efficiency control elements such as super surfaces, while controlling the size of the lens to adapt to the space limitations of portable devices such as mobile phones.

[0127] This range forms a reasonable match with the imaging surface size (such as the IH mentioned earlier).

[0128] For the common small and medium-sized imaging surface in the field of consumer electronics, the FOV of 79.356°-93.649° can balance between the "shooting range" and the "picture detail" - neither too narrow to cause the picture "cramped", nor too wide to reduce the light received by each pixel (affecting the picture quality).

[0129] In practical applications (such as mobile phone cameras, security monitoring), this field of view can cover most daily scenes: it can take group photos of multiple people, and it can also preserve enough environmental levels in landscape photography, while avoiding edge distortion to affect user experience.

[0130] In addition, the setting of the range boundary includes the consideration of the difficulty of aberration correction.

[0131] The upper limit is 93.649°, and beyond this angle, the light in the edge field of view has a too large incidence angle on the lens surface, and the aberration correction pressure of the traditional lens increases sharply. Even if advanced elements such as super surfaces are used, more complex microstructure design is needed to compensate, which may increase the processing cost or reduce the yield of mass production. The lower limit is 79.356°, and below this angle, although the difficulty of aberration correction can be reduced, the "scene adaptability" of the lens will be weakened. Especially in portable devices, users have high demand for "one lens for multiple purposes", and a too narrow field of view will limit the practicality of the device.

[0132] In summary, the range limit of 79.356°<FOV<93.649° is the optimal balance between "imaging range, picture quality control, and volume adaptation" of the optical lens, which not only meets the demand for wide-angle view in daily shooting, but also avoids the volume expansion and performance loss caused by excessive design by controlling the upper limit of the field of view. It is an ideal choice for consumer electronics and portable imaging devices.

[0133] In some embodiments, 0.109 < f1 / f3 < 0.595, where f1 is the effective focal length of the first lens and f3 is the effective focal length of the third lens.

[0134] Optical power (the reciprocal of focal length, φ = 1 / f) is a core parameter that measures the ability of a lens to converge or diverge light: the larger the optical power (the smaller the focal length), the stronger the deflection ability of the lens to light. The generation of chromatic aberration is due to the difference in refractive index of light of different wavelengths, resulting in different focusing positions after passing through the lens. The distribution of chromatic aberration is directly affected by the distribution of optical power. Different lenses have different optical power ratios, and their "chromatic aberration contribution" is also different. The first lens (usually the front converging element) and the third lens (the middle regulating element) are the key links in the distribution of optical power. The limitation of their focal length ratio (f1 / f3) is essentially to control the optical power ratio (φ3 / φ1 = f1 / f3) of the two, and to achieve the balance of the total chromatic aberration of the system by making the chromatic aberration characteristics of the two complementary.

[0135] The lower limit ensures that the optical power of the first lens is not much greater than that of the third lens (i.e., φ1 is not much greater than φ3). If f1 / f3 < 0.109, it means that f1 is much smaller than f3 (φ1 is much greater than φ3), the first lens will bear most of the optical power in the system, and its deflection ability of light is too strong, which will lead to: The color aberration contribution of the first lens is too high, and the dispersion effect of a single lens is difficult to be compensated by other elements (especially when the first lens is a low Abbe number material, the dispersion is more significant); The deflection angle of light in the first lens is too large, and different wavelengths of light are significantly separated at the front end, making it difficult for subsequent optical elements to re-converge them, which indirectly increases the difficulty of color aberration correction.

[0136] The lower limit can avoid excessive concentration of optical power on the first lens, allowing the third lens to share part of the optical power and reserve space for color aberration complementarity between the two. The upper limit limits the optical power of the first lens from being too weak relative to the third lens (i.e., φ1 is not too small). If f1 / f3 > 0.595, it means that f1 and f3 are not far apart (f1 is close to or greater than f3), i.e., φ1 is close to or smaller than φ3, and the optical power of the third lens is too strong, which will lead to: The deflection of light in the middle light path is too severe, and the color aberration contribution of the third lens is too high, while the first lens is too weak to provide effective compensation; If the third lens is a high dispersion material, the excessive optical power will amplify its dispersion defects, leading to deterioration of the total color aberration of the system, and subsequent elements are difficult to correct.

[0137] The upper limit ensures that the first lens retains sufficient optical power to form a mechanism of "front-end preliminary regulation + middle coordinated correction" with the third lens, avoiding a single lens from bearing excessive color aberration.

[0138] The material dispersion characteristics (such as Abbe number, the smaller the Abbe number, the more significant the dispersion) of different lenses are different. Through the ratio limit of f1 / f3, the dispersion characteristics of the first lens and the third lens can be precisely complementary.

[0139] If the first lens adopts a low Abbe number material (strong dispersion), f1 / f3 > 0.109 is needed to avoid its excessive optical power (f1 is too small) and reduce the original color aberration; at the same time, the third lens adopts a high Abbe number material (weak dispersion), and f1 / f3 < 0.595 is needed to retain a certain optical power (f3 should not be too small) so that it can specifically offset the color aberration of the first lens.

[0140] Conversely, if the third lens has stronger dispersion (low Abbe number), its optical power needs to be limited by f1 / f3 < 0.595 to avoid too large φ3 caused by too small f3, while the first lens (high Abbe number, weak dispersion) is required to take more optical power by f1 / f3 > 0.109 to reduce the total chromatic aberration.

[0141] The range of 0.109-0.595 provides flexible space for the synergistic design of “material dispersion + optical power ratio”, ensuring that the chromatic aberration contributions of the two can be offset each other, and finally achieving the minimization of system chromatic aberration.

[0142] The ratio range also adapts the overall optical balance of the lens: balanced optical power distribution can reduce performance fluctuations caused by excessive burden on a certain lens (e.g., temperature changes have a more significant impact on high optical power lenses). Especially in consumer electronics, vehicle imaging and other scenarios with high stability requirements, this design can ensure that the complementary relationship between the chromatic aberration of the first and third lenses remains stable in different environments (such as high and low temperatures, vibration), maintaining the consistency of imaging quality.

[0143] In summary, the limitation of 0.109 < f1 / f3 < 0.595 precisely regulates the optical power ratio of the first and third lenses, balances their chromatic aberration contributions, and is an optimized design that takes into account both the rationality of optical power distribution and the complementarity of dispersion characteristics, which can effectively suppress system chromatic aberration and improve imaging clarity.

[0144] In some embodiments, 1.605 < f3 / f < 9.33, where f3 is the effective focal length of the third lens, and f is the effective focal length of the optical lens.

[0145] The total optical power (1 / f) of an optical lens is the superposition of the optical power of each lens (φtotal = φ1 + φ2 + φ3 +...). As a key intermediate element, the ratio of the focal length f3 of the third lens to the total focal length f of the system (f3 / f) directly reflects the proportion of its optical power (φ3 = 1 / f3) in the system.

[0146] When f3 / f > 1, f3 > f, which means φ3 < φtotal (the optical power of the third lens is smaller than the total optical power of the system), indicating that it undertakes a relatively moderate light deflection task and plays a more auxiliary regulatory role.

[0147] This range (1.605-9.33) further specifies that the focal length of the third lens is 1.605-9.33 times the total focal length of the system, and the optical power is only 1 / 1.605 to 1 / 9.33 of the total optical power of the system, which is a “weak optical power element”. Its core function is to finely compensate for the aberration of the previous lens, rather than dominating light convergence / divergence.

[0148] If f3 / f < 1.605 (i.e., f3 is close to or smaller than f), the optical power of the third lens will be too large (φ3 is close to or exceeds φtotal), which will cause the light rays in the middle light path to be deflected too violently, introducing new aberrations (such as spherical aberration, coma), thereby increasing the difficulty of system correction. The third lens bears too much optical power, and the connection with the optical power of the front / rear lenses is unbalanced, causing the light beam propagation angle to suddenly change, affecting the imaging consistency. The lower limit ensures that the optical power of the third lens is not too strong, allowing it to compensate for aberrations in a "moderate control" manner, avoiding interference with the overall light path of the system.

[0149] If f3 / f > 9.33 (i.e., f3 is much larger than f), the optical power of the third lens will be too weak (φ3 is too small), which will result in insufficient correction of the aberrations (such as chromatic aberration, field curvature) generated by the previous lenses, especially in wide-angle systems, where edge aberrations cannot be effectively suppressed. The middle light path lacks effective regulation, and the light beam propagation direction deviates from the design expectation, causing the image quality difference between the center and the edge of the imaging surface to expand (such as edge blur). The upper limit ensures that the third lens retains sufficient optical power, allowing it to compensate for the aberrations of the previous elements, maintaining the image quality across the entire field of view. The "weak optical power" characteristic of the third lens makes it suitable for fine correction tasks. For example, when the previous lens (such as the first lens) generates slight chromatic aberration, the third lens can use its material dispersion characteristics (such as high Abbe number) and moderate optical power to slightly deflect light rays of different wavelengths, re-converging them to the same imaging surface; if the previous lens introduces field curvature (the clarity of the center and edge of the image is inconsistent), the third lens can balance the focusing distances of different fields of view through curve design and optical power regulation. The range of 1.605-9.33 provides a parameter space for this "precise fine-tuning", avoiding over-correction or under-correction. In addition, the moderate optical power of the third lens can reduce performance fluctuations caused by material non-uniformity and temperature changes (high-power elements are more sensitive to manufacturing errors). At the same time, its "weak regulation" characteristic does not require excessive curvature or thickness, allowing it to maintain a compact structure and be compatible with small-sized lens design (such as the TTL / IH ratio limit described earlier).

[0150] This range is particularly suitable for scenarios that require high "balanced performance", such as consumer electronics and vehicle-mounted imaging. For devices such as mobile phone lenses and security cameras, it is necessary to cover the medium and wide-angle field of view while ensuring that the image has no obvious aberrations. The moderate optical power of the third lens can improve the imaging consistency without increasing the size of the lens.

[0151] In addition, compared to a strong focusing lens (f3 is close to f), the third lens in this range can reduce the requirement for processing precision, which is beneficial for cost control in mass production, and also reduces the impact of assembly errors on the light path.

[0152] In summary, the limitation of 1.605 < f3 / f < 9.33, by positioning the third lens as a "weak light power auxiliary correction element", ensures its aberration compensation ability while avoiding interference with the overall optical path balance of the system, is an optimized design that takes into account imaging quality, compactness and mass production feasibility.

[0153] In some embodiments, 1.79 < IH / f < 2.2, where IH is the diagonal length of the effective pixel area on the imaging surface of the optical lens, and f is the effective focal length of the optical lens.

[0154] The ratio of IH / f essentially reflects the "size of the imaging surface relative to the focal length of the lens", which is directly related to the field of view and the imaging resolution of the lens. The larger the ratio, the larger the imaging surface at the same focal length, or the shorter the focal length at the same imaging surface, the wider the field of view (the larger the field of view) that the lens can capture.

[0155] The range of 1.79-2.2 means that the diagonal length of the imaging surface is 1.8-2.2 times the focal length of the lens, which belongs to the "medium wide angle adaptation interval", which not only ensures sufficient imaging range, but also avoids the loss of resolution caused by too large ratio.

[0156] If IH / f < 1.79, there are two cases: The imaging surface IH is too small: at the same focal length, the imaging surface cannot match the field of view of the lens, resulting in the edge light being unable to be effectively received, which is equivalent to "the lens can see a wider range than the sensor can record", causing waste of the field of view.

[0157] The focal length f is too large: at the same imaging surface, the focal length of the lens is too long, the field of view is too narrow (such as long focal characteristics), and it is difficult to capture large scenes (such as indoor and group photos), limiting the application scenarios of the lens. The setting of the lower limit ensures that the ratio of the imaging surface and the focal length can cover the medium wide angle field of view, meeting the demand for "scene integrity" in daily shooting.

[0158] If IH / f > 2.2, it means that the imaging surface is too large at the same focal length, or the focal length is too short at the same imaging surface.

[0159] At this time, the field of view of the lens is too large, the spatial range covered by each pixel increases (the "pixel density" of light on the imaging surface decreases), which may cause the details of the picture to be blurred (resolution dilution), especially in low light environments, the light energy received by the pixel decreases, and the noise increases significantly.

[0160] Excessive short focal length can exacerbate aberrations (such as distortion, chromatic aberration), and excessive imaging surface can amplify the effect of these aberrations on the edge of the field of view, resulting in picture edge quality decay. In combination with the field of view (FOV) range of 79.356°-93.649° as described above, the ratio of IH / f = 1.79-2.2 can achieve the compatibility of “medium wide-angle view” and “sufficient resolution”. For example, when f = 5mm, IH needs to be between 8.95mm-11mm, at this time the lens can cover a field of view of about 80°-90° (suitable for most daily scenes), and the pixels of the imaging surface can fully utilize the incident light (avoiding insufficient light energy “shared” by pixels due to excessive IH). The reasonable limit of IH / f can avoid excessive shortening of focal length to expand the field of view (resulting in complex lens structure), or excessive increase of imaging surface to improve resolution (resulting in forced increase of TTL), and finally balance among “field of view-resolution-volume”.

[0161] This range is particularly suitable for consumer electronics (such as mobile phones, tablets) and portable imaging devices.

[0162] For mobile phone lenses, IH is usually 8-12mm (corresponding to mainstream sensor size), f is 4-6mm (consistent with small size lens design), IH / f falls within the range of 1.79-2.2, which can not only shoot wide scenes (such as landscapes, group photos), but also ensure clear photo details (pixels are not diluted too much). In the scene of vehicle-mounted camera, security monitoring, etc., this ratio can ensure that the lens covers enough monitoring range in limited volume, while clearly capturing the details of distant targets (such as vehicles, pedestrians), balancing “wide coverage” and “high recognition”.

[0163] In summary, the limit of 1.79<IH / f<2.2, by precisely regulating the ratio of imaging surface and lens focal length, can ensure medium wide-angle view while avoiding resolution loss, which is an optimized design considering imaging performance, system compatibility and application scenario requirements, and provides core parameter support for the optical system of consumer electronics and portable devices.

[0164] In order to more clearly illustrate the performance of the optical lens provided by the embodiments of the present application, the following provides several embodiments of optical lenses and specific numerical designs of optical parameters of the corresponding optical lenses in each embodiment for reference, wherein, without special description, the units of various parameters related to size, such as thickness / distance, radius, focal length, length, are all millimeters (mm).

[0165] Embodiment 1: Table 1 is the optical parameters of the lens of Example 1, where f1 is the focal length of the first lens L1, f2 is the focal length of the second lens L2, f3 is the focal length of the third lens L3, f4 is the focal length of the fourth lens L4, f5 is the focal length of the fifth lens L5, f is the effective focal length of the lens, FNO is the F-number of the lens, TTL is the total track length of the lens, IH is the diagonal length of the effective pixel area on the imaging surface of the lens, FOV is the maximum field of view angle of the lens, and Lm is the distance from the super surface close to the object side to the imaging surface along the optical axis.

[0166]

[0167] Table 1 Table 2 is the ratio of the optical parameters of the lens of Example 1.

[0168]

[0169] Table 2 Table 3 is the specific surface type parameters of the lens of Example 1.

[0170]

[0171] Table 3 Table 4 is the aspheric coefficients of the lens of Example 1. In optical design, aspheric coefficients are mathematical parameters used to describe the surface shape of an aspheric lens. Unlike spherical lenses (whose surface is a standard sphere and only needs to be defined by the radius of curvature), the surface curvature of an aspheric lens varies with the radial distance, and its shape needs to be accurately described by specific formulas and coefficients to achieve better optical performance (such as correcting aberrations, reducing volume, etc.).

[0172] The surface equation of an aspheric surface usually takes the radial distance (r) as the variable, and the standard form is as follows:

[0173] Where the meaning of each parameter (coefficient) is as follows: K (Conic Constant): describes the basic conic section type of the aspheric surface, and is the core parameter that determines the overall shape of the aspheric surface.

[0174] Different K values correspond to different conic sections: K=-1: parabolic surface; K<-1: hyperbolic surface; -1<K<0: ellipsoidal surface; K=0: spherical surface (in this case, the aspheric surface degenerates into a standard spherical surface); K>0: oblate spheroid.

[0175] A4, A6, A8...A 2n(high order term coefficients): these are high order polynomial coefficients, used to modify the shape of the base conic, further optimizing the curvature variation of the asphere, to precisely correct aberrations (such as spherical aberration, coma, etc.).

[0176] The subscript number indicates the power of r (e.g. A4 corresponds to r 4 6 The sign and magnitude of the coefficients determine the degree of deviation of the surface at different radial positions.

[0177] Generally, the low order terms (e.g. A4, A6) have a larger impact on the surface shape, while the high order terms (e.g. A 18 , A 20 ) are used for fine tuning, to make the surface more conform to the optical design requirements.

[0178] c is the vertex curvature, which is the inverse of the radius of curvature R at the vertex, i.e. c = 1 / R, and its main function is to describe the basic curvature of the asphere at the vertex position (r = 0, which is the topmost point of the center of the surface).

[0179] All the aspherical surface types in this article are defined by this standard form.

[0180]

[0181] Table 4 Table 5 is the diffraction optical path coefficient of the superlens S10 surface of Example 1, where M is the diffraction order. In the design of superlenses, the diffraction optical path coefficient is a key parameter that describes the phase modulation characteristics of the superlens surface, and together with the diffraction order M determines the control ability (such as focusing, deflection, imaging, etc.) of the superlens to different wavelengths and different directions of incident light.

[0182] Mathematically, it can be simplified as: Φ( r )=∑ n C n ⋅ f n ( r , M , λ ) where: Φ( r ) is the phase modulation amount of a point on the surface of the superlens (radial coordinate r ); C n i.e. "diffraction optical path coefficient", determines the weight of each order modulation term; f n ( r , M , λ ​) is a function (such as a polynomial term, a trigonometric function term, etc.) related to the position r , the diffraction order M , the incident light wavelength λ ; Diffraction order M: represents the order of diffraction of light after passing through the superlens (such as M=0 for straight light, M=±1, ±2, etc. for different high-order diffracted light), and the superlens is usually designed to concentrate energy on the target order (such as M=1 order when focusing).

[0183]

[0184] Table 5 Figure 3 The diffraction modulation transfer function (MTF) curve of the optical lens of Example 1 is shown. The MTF curve is used to evaluate the imaging quality of the optical lens, and the core is the relationship between spatial frequency and modulation.

[0185] The horizontal axis is the spatial frequency (Spatial Frequency), with units of "cycles / mm (cycles per millimeter of line pairs)", representing the number of black and white line pairs that can be distinguished within 1 millimeter (such as 30 cycles / mm, that is, 30 groups of black and white line pairs within 1 mm), and the larger the value, the more detailed the lens requires to distinguish details.

[0186] The vertical axis is the contrast transfer ratio (Modulation), ranging from 0 to 1.

[0187] 1=perfect transmission (black and white line contrast 100% preserved); 0=complete failure to transmit (lines are blurred into one piece, contrast is lost).

[0188] The flatter and higher the MTF curve, the better the imaging quality of the optical system.

[0189] High frequency (right side, such as >60 cycles / mm): reflects the resolution of "fine details" (such as text edges, hair). If the high frequency curve is high, it means that the lens can clearly capture details without blurring.

[0190] Low frequency (left side, such as <20 cycles / mm): reflects the contrast preservation ability of "large outlines and large blocks". If the low frequency is close to 1, it means that the overall picture is transparent and the contrast is normal.

[0191] Optical lenses are limited by physical diffraction, and MTF has a natural upper limit (close to the highest curve). Due to lens errors and aberrations, the actual lens curve will be lower than this limit.

[0192] High MTF value (such as >0.8): clear and sharp picture, suitable for shooting landscapes and portraits (rich in details).

[0193] Low MTF value (such as <0.5): picture is blurred, details are lost.

[0194] In Figure 3 , a plurality of curves correspond to diffraction MTFs in different situations. Specifically, from top to bottom, each curve represents: the upper limit MTF of the embodiment, the MTF at 0 degree field of view, the radial MTF at 26.646 degrees field of view, the radial MTF at 46.825 degrees field of view, the tangential MTF at 26.646 degrees field of view, and the tangential MTF at 46.825 degrees field of view.

[0195] From Figure 3 , it can be seen that the embodiment 1 lens performs well at different field angles in the low frequency band; in the high frequency band, the radial performance is good, while the tangential performance at 46.825 degrees field of view is relatively general. Comprehensive analysis of the whole frequency band shows that the overall performance at 26.646 degrees field of view is better than that at 46.825 degrees field of view.

[0196] Embodiment 2: Table 6 is the optical parameters of the lens of embodiment 2.

[0197]

[0198] Table 6 Table 7 is the optical parameter ratio of the lens of embodiment 2.

[0199]

[0200] Table 7 Table 8 is the specific surface shape parameters of the lens of embodiment 2.

[0201]

[0202] Table 8 Table 9 is the aspheric coefficient of the lens of embodiment 2.

[0203]

[0204] Table 9 Table 10 is the diffraction optical path coefficient of the super lens S10 surface of embodiment 2.

[0205]

[0206] Table 10 Figure 4 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of embodiment 2 is shown.

[0207] exist Figure 4 In the figure, multiple curves correspond to the diffraction MTF under different circumstances. Specifically, from top to bottom, the curves represent: the upper limit MTF of this embodiment, the MTF at a 0-degree field of view, the radial MTF at a 38.647-degree field of view, the radial MTF at a 39.678-degree field of view, the radial MTF at a 25.952-degree field of view, the tangential MTF at a 25.952-degree field of view, the tangential MTF at a 38.647-degree field of view, and the tangential MTF at a 39.678-degree field of view.

[0208] from Figure 4 It can be observed that the radial MTF performance of the lens is consistent across all FOV angles, with minimal variation. However, as the FOV increases, the tangential MTF performance shows significant differentiation—a significant decrease occurs when the FOV increases from 25.952 to 38.647 degrees. More notably, even with a slight increase in FOV from 38.647 to 39.678 degrees (less than a 1-degree change), the tangential MTF still experiences a significant decrease, demonstrating the strong sensitivity of FOV to tangential imaging performance within this range.

[0209] Example 3: Table 11 shows the optical parameters of the lens of Example 3.

[0210]

[0211] Table 11 Table 12 shows the optical parameter ratios of the lens of Example 3.

[0212]

[0213] Table 12 Table 13 shows the specific surface parameters of the lens of Example 3.

[0214]

[0215] Table 13 Table 14 shows the aspheric coefficients of the lens of Example 3.

[0216]

[0217] Table 14 Table 15 shows the diffraction path coefficient of the S10 surface of the superlens in Example 3.

[0218]

[0219] Table 15 Figure 5The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of Embodiment 3 is shown.

[0220] In Figure 5 , the plurality of curves respectively correspond to the diffraction MTF under different conditions. Specifically, from top to bottom, each curve represents, in turn: the upper limit MTF of the present embodiment, the MTF under a 0-degree field of view, the radial MTF under a 22.500-degree field of view, the tangential MTF under a 22.500-degree field of view, the radial MTF under a 40.500-degree field of view, the radial MTF under a 46.000-degree field of view, the tangential MTF under a 40.500-degree field of view, and the tangential MTF under a 46.000-degree field of view.

[0221] From Figure 5 It can be observed that under the test conditions of the present embodiment, two key imaging characteristics of the lens can be observed: first, as the field of view increases, the tangential MTF exhibits a clear downward trend; second, the tangential MTF under a 22.500-degree field of view outperforms the corresponding radial MTF under a larger field of view.

[0222] Embodiment 4: Table 16 is the optical parameters of the lens of Embodiment 4.

[0223]

[0224] Table 16 Table 17 is the ratio of the optical parameters of the lens of Embodiment 4.

[0225]

[0226] Table 17 Table 18 is the specific surface shape parameters of the lens of Embodiment 4.

[0227]

[0228] Table 18 Table 19 is the aspheric surface coefficients of the lens of Embodiment 4.

[0229]

[0230] Table 19 Table 20 is the diffraction optical path coefficients of the superlens S10 surface of Embodiment 4.

[0231]

[0232] Table 20 Figure 6 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of Embodiment 4 is shown.

[0233] In Figure 6 the figure, the multiple curves respectively correspond to the diffraction MTFs in different situations. Specifically, from top to bottom, the curves represent, in turn, the upper limit MTF of the present embodiment, the MTF at 0 degree field angle, the radial MTF at 39.678 degree field angle, the radial MTF at 36.148 degree field angle, the radial MTF at 22.156 degree field angle, the tangential MTF at 22.156 degree field angle, the tangential MTF at 36.148 degree field angle, and the tangential MTF at 39.678 degree field angle.

[0234] In combination Figure 6 it can be seen that, in the test scenario of the present embodiment, the performance gap between the radial MTF and the tangential MTF at the same field angle dimension continues to widen during the increase of the field angle, and the differentiation trend is particularly prominent. For example, at 39.678 degree field angle, the radial MTF performs better than that at 22.156 degree field angle; however, the tangential MTF at this field angle presents a significantly deteriorated trend compared to that at 22.156 degree field angle.

[0235] Embodiment 5: Table 21 is the optical parameters of the lens of embodiment 5.

[0236]

[0237] Table 21 Table 22 is the optical parameter ratio of the lens of embodiment 5.

[0238]

[0239] Table 22 Table 23 is the specific surface shape parameters of the lens of embodiment 5.

[0240]

[0241] Table 23 Table 24 is the aspheric coefficients of the lens of embodiment 5.

[0242]

[0243] Table 24 Table 25 is the diffraction optical path coefficients of the superlens S10 surface of embodiment 5.

[0244]

[0245] Table 25 Figure 7 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of embodiment 5 is shown.

[0246] In Figure 7 the figure, the multiple curves respectively correspond to the diffraction MTFs in different situations. Specifically, from top to bottom, the curves represent, in order, the upper limit MTF of the present embodiment, the MTF at 0 degree field of view, the radial MTF at 20.000 degree field of view, the tangential MTF at 20.000 degree field of view, the radial MTF at 36.000 degree field of view, the tangential MTF at 36.000 degree field of view, the tangential MTF at 41.000 degree field of view, and the radial MTF at 41.000 degree field of view.

[0247] In combination Figure 7 it can be seen that, in the test scenario of the present embodiment, as the field of view angle increases, the tangential MTF performance shows a trend of being superior to the radial MTF. Specifically, at 36.000 degree field of view, the radial MTF performance is still superior to the tangential MTF; and when the field of view angle increases to 41.000 degree, the trend changes, the tangential MTF performance reverses the radial MTF, showing a better imaging performance.

[0248] Embodiment 6: Table 26 is the optical parameter of the lens of embodiment 6.

[0249]

[0250] Table 26 Table 27 is the optical parameter ratio of the lens of embodiment 6.

[0251]

[0252] Table 27 Table 28 is the specific surface shape parameter of the lens of embodiment 6.

[0253]

[0254] Table 28 Table 29 is the aspheric coefficient of the lens of embodiment 6.

[0255]

[0256] Table 29 Table 30 is the diffraction optical path coefficient of the superlens S10 surface of embodiment 6.

[0257]

[0258] Table 30 Figure 8 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of embodiment 6 is shown.

[0259] In Figure 8 Specifically, from top to bottom, the curves represent, in order, the upper limit MTF of the embodiment, the MTF at 0 degree field of view, the radial MTF at 16.000 degree field of view, the radial MTF at 32.000 degree field of view, the tangential MTF at 16.000 degree field of view, the tangential MTF at 32.000 degree field of view, the radial MTF at 41.000 degree field of view, and the tangential MTF at 41.000 degree field of view.

[0260] In combination with Figure 8 It can be seen that, in the test scenario of the embodiment, as the field of view angle increases, the tangential MTF and the radial MTF exhibit a certain regularity: as the spatial frequency increases, the two gradually tend to be consistent. Specifically, when the field of view angle is 41.000 degrees, after the spatial frequency exceeds 90, the tangential MTF and the radial MTF exhibit the same performance, achieving performance unification.

[0261] Embodiment 7: Table 31 is the optical parameter of the lens of embodiment 7.

[0262]

[0263] Table 31 Table 32 is the optical parameter ratio of the lens of embodiment 7.

[0264]

[0265] Table 32 Table 33 is the specific surface shape parameter of the lens of embodiment 7.

[0266]

[0267] Table 33 Table 34 is the aspheric coefficient of the lens of embodiment 7.

[0268]

[0269] Table 34 Table 35 is the diffraction optical path coefficient of the superlens S10 surface of embodiment 7.

[0270]

[0271] Table 35 Figure 9 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of embodiment 7 is shown.

[0272] In Figure 9In the figure, the multiple curves respectively correspond to the diffraction MTFs in different situations. Specifically, from top to bottom, the curves represent, in order, the upper limit MTF of the embodiment, the MTF at 0 degree field angle, the radial MTF at 17.200 degree field angle, the radial MTF at 34.400 degree field angle, the tangential MTF at 17.200 degree field angle, the radial MTF at 44.000 degree field angle, the tangential MTF at 34.4 degree field angle, and the tangential MTF at 44.000 degree field angle.

[0273] In combination Figure 9 It can be observed that, in the test scenario of the embodiment, as the field angle continuously increases, the tangential MTF of the lens exhibits a significant deterioration trend, and the performance drops seriously. Specifically, the tangential MTF at 34.400 degree field angle is poorer than that at 17.200 degree field angle; and as the field angle continues to increase to 44.000 degree, the tangential MTF drops more than that at 34.400 degree field angle, exhibiting a feature that the tangential MTF deteriorates rapidly as the field angle increases.

[0274] Embodiment 8: Table 36 is the optical parameters of the lens of embodiment 8.

[0275]

[0276] Table 36 Table 37 is the optical parameter ratio of the lens of embodiment 8.

[0277]

[0278] Table 37 Table 38 is the specific surface shape parameters of the lens of embodiment 8.

[0279]

[0280] Table 38 Table 39 is the aspheric coefficients of the lens of embodiment 8.

[0281]

[0282] Table 39 Table 40 is the diffraction optical path coefficients of the superlens S10 surface of embodiment 8.

[0283]

[0284] Table 40 Figure 10 The diffraction modulation transfer function (Diffraction MTF) curve of the optical lens of embodiment 8 is shown.

[0285] InFigure 10 In the figure, the plurality of curves respectively correspond to diffraction MTFs in different situations. Specifically, from top to bottom, the curves represent, in order: the upper limit MTF of the embodiment, the MTF at a 0-degree field angle, the radial MTF at a 20.500-degree field angle, the radial MTF at a 32.800-degree field angle, the radial MTF at a 42.000-degree field angle, the tangential MTF at a 20.500-degree field angle, the tangential MTF at a 32.800-degree field angle, and the tangential MTF at a 42.000-degree field angle.

[0286] In combination Figure 10 It can be seen that, in the test scenario of the embodiment, as the field angle gradually expands, the tangential MTF and the radial MTF of the lens both exhibit a deterioration trend, and the deterioration rates of the two are approximately the same, which reflects that the influence of the field angle on the MTF performance in the two directions is basically the same.

[0287] While a number of embodiments of the disclosure have been shown and described herein, it is to be understood that such embodiments are merely exemplary of the many possible embodiments of the disclosure. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the spirit and scope of the disclosure. It is therefore intended that the disclosure not be limited to the embodiments described herein, but that the disclosure have the full scope as set forth in the claims.

Claims

1. An optical lens, characterized in that: Along the optical axis of the optical lens from the object side to the image side, it includes: a first lens having positive optical power, a second lens having negative optical power, The third lens has positive optical power, The fourth lens has negative optical power, A fifth lens having optical power, wherein the fifth lens is a metalens.

2. The optical lens according to claim 1, wherein: The fifth lens is a super lens having a function of filtering a specific wavelength.

3. The optical lens according to claim 2, wherein: The fifth lens includes: substrate, and The microstructure and filler are formed on the substrate as a metasurface, wherein the filler covers the microstructure and forms a filling plane, and the filling plane is coated with a filter film for filtering specific wavelengths.

4. The optical lens according to claim 3, wherein: The metasurface is arranged on the object side of the substrate.

5. The optical lens according to claim 4, wherein: 0.168 <Lm / TTL<0.225, Wherein Lm is the distance from the metasurface close to the object side to the imaging surface along the optical axis, and TTL is the total length of the optical lens.

6. The optical lens according to claim 3, wherein: The height of the metasurface is between 80 and 150 nanometers.

7. The optical lens according to claim 1, wherein: -80 <f5 / f<38.968, Wherein, f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical lens.

8. The optical lens according to claim 1, wherein: 0.513 <TTL / IH<0.701, Wherein, TTL is the total length of the optical lens, and IH is the diagonal length of the effective pixel area on the imaging surface of the optical lens.

9. The optical lens according to claim 1, wherein: -38.57 <f2 / f<-4.004, Wherein f2 is the effective focal length of the second lens, and f is the effective focal length of the optical lens.

10. The optical lens according to claim 1, wherein: 1.81 <CT1 / CT2<2.82, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

11. The optical lens according to claim 1, wherein: 79.356° <FOV<93.649°, Wherein FOV is the maximum field of view of the optical lens.

12. The optical lens according to claim 1, wherein: 0.109 <f1 / f3<0.595, Wherein f1 is the effective focal length of the first lens, and f3 is the effective focal length of the third lens.

13. The optical lens according to claim 1, wherein: 1.605 <f3 / f<9.33, Wherein f3 is the effective focal length of the third lens, and f is the effective focal length of the optical lens.

14. The optical lens according to claim 1, wherein: 1.79 <IH / f<2.2, Wherein IH is the diagonal length of the effective pixel area on the imaging surface of the optical lens, and f is the effective focal length of the optical lens.

Images