A dual visible and infrared lens and electronic device for remote monitoring of use
By rationally arranging six lenses and matching their refractive indices, combined with a glass-plastic hybrid design, the problems of focus drift and temperature difference effects in long-distance monitoring were solved, enabling stable imaging of the lens under day-night switching and temperature difference environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XIAMEN LEADING OPTICS
- Filing Date
- 2026-04-28
- Publication Date
- 2026-06-30
AI Technical Summary
Existing dual-light lenses have problems in long-distance monitoring scenarios, such as focus drift caused by infrared supplementation at night, aberrations and image quality degradation due to increasing the aperture, and lens expansion and contraction and focus instability caused by outdoor temperature differences.
The system employs a rational arrangement of six lenses and precise matching of refractive index and mirror curvature. In particular, the first lens features a dual-plane structure combined with a glass-plastic hybrid design. Plastic and glass lenses are used to offset the refraction deviation of infrared supplementary light and suppress the effects of temperature difference, ensuring a stable focus.
Maintaining focus stability during day-night cycles and changes in ambient temperature ensures clarity and continuity of long-distance monitoring, and improves the imaging stability and consistency of the lens under different lighting and temperature conditions.
Smart Images
Figure CN122307882A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lens technology, and in particular to a visible light and infrared dual-light lens and electronic device for long-distance monitoring. Background Technology
[0002] In the field of security monitoring, the core requirement for long-distance monitoring is to achieve accurate target identification and all-weather coverage without blind spots. As the requirements for monitoring accuracy and environmental adaptability increase, single-spectrum imaging lenses can no longer meet the needs, and dual-light fusion lenses that combine visible light and thermal imaging have become the mainstream approach.
[0003] To address the shortcomings of single-spectrum imaging, dual-light fusion lenses combining visible light and thermal imaging have become the mainstream approach. However, existing dual-light lenses still have many drawbacks in long-distance monitoring scenarios: traditional single lenses are limited by physical constraints, infrared supplementary lighting at night can easily cause focus drift, increasing the aperture can cause aberrations and image quality degradation, and outdoor temperature differences can also cause thermal expansion and contraction of the lens and unstable focus. Summary of the Invention
[0004] In view of this, the object of the present invention is to provide a visible light and infrared dual-lens lens and electronic device for long-distance monitoring. This lens can at least solve one of the technical shortcomings mentioned in the background art. According to one aspect of the present invention, a visible light and infrared dual-beam lens for long-distance monitoring is provided, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side; the first lens has a plane object side and a plane image side; the second lens has a negative refractive index, and its object side is convex and its image side is concave; the third lens has a positive refractive index, and its object side and image side are convex; the fourth lens has a positive refractive index, and its object side and image side are convex; the fifth lens has a negative refractive index, and its object side is concave and its image side is convex; the sixth lens has a positive refractive index, and its object side and image side are convex.
[0005] This invention, through the rational arrangement of six lenses and the precise matching of refractive index and mirror curvature, especially the setting of the double-plane structure of the first lens, can effectively offset the light refraction deviation during infrared supplementation, while suppressing the influence of lens thermal expansion and contraction caused by outdoor temperature differences on the optical axis, reducing focus drift, and ensuring that the lens can maintain focus stability when switching between day and night and when the ambient temperature changes, thus ensuring the clarity and continuity of long-distance monitoring.
[0006] According to another aspect of the present invention, an electronic device is provided, comprising a visible light and infrared dual-lens lens for long-distance monitoring as described above; and an image sensor configured to receive an image formed by the visible light and thermal imaging dual-lens lens for long-distance monitoring. The advantage of this electronic device in this technical solution relies on the visible light and thermal imaging dual-lens lens for long-distance monitoring, which will not be elaborated upon here. Attached Figure Description
[0007] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0008] Figure 1 This is a structural diagram of the optical system of the lens in Example 1.
[0009] Figure 2 The image shows the MTF (Mean Transformer Format) of the lens in Example 1 in the visible light band.
[0010] Figure 3 The MTF diagram of Example 1 is shown in the near-infrared band.
[0011] Figure 4 This is the vertical axis color difference diagram of Example 1.
[0012] Figure 5 This is a relative illumination diagram for Example 1.
[0013] Figure 6 This is a structural diagram of the optical system of the lens in Example 2.
[0014] Figure 7 This is the MTF diagram of the lens in the visible light band in Example 2.
[0015] Figure 8 This is the MTF diagram of Example 2 in the near-infrared band.
[0016] Figure 9 This is the vertical axis color difference diagram of Example 2.
[0017] Figure 10 This is a relative illumination diagram for Example 2.
[0018] Figure 11 This is a schematic diagram of the structure of the electronic device of the present invention.
[0019] L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; L5, fifth lens; L6, sixth lens; ST, aperture stop; CG, filter; G, protective glass; IMA, imaging plane. Detailed Implementation
[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the invention. Similarly, the following embodiments are only some, not all, embodiments of the present invention, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] A visible light and infrared dual-beam lens for long-distance monitoring includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side. The first lens has a flat object side and a flat image side. The second lens has a negative refractive index, a convex object side, and a concave image side. The third lens has a positive refractive index, a convex object side, and a convex image side. The fourth lens has a positive refractive index, a convex object side, and a convex image side. The fifth lens has a negative refractive index, a concave object side, and a convex image side. The sixth lens has a positive refractive index, a convex object side, and a convex image side.
[0022] Among them, reference Figure 1 , Figure 6 As shown, Figure 1 This is a structural diagram of the optical system of embodiment 1 of the lens of the present invention; Figure 6 This is a structural diagram of the optical system of embodiment 2 of the lens of the present invention. In the figure, an aperture stop is provided between the second lens and the third lens, and a protective glass is provided after the sixth lens. The first lens is indicated by the symbol L1, the second lens by the symbol L2, the third lens by the symbol L3, the fourth lens by the symbol L4, the fifth lens by the symbol L5, the sixth lens by the symbol L6, the aperture stop by the symbol ST, the protective glass by the symbol G, and the imaging plane by the symbol IMA.
[0023] This invention, through the rational arrangement of six lenses and the precise matching of refractive index and mirror curvature, especially the setting of the double-plane structure of the first lens, can effectively offset the light refraction deviation during infrared supplementation, while suppressing the influence of lens thermal expansion and contraction caused by outdoor temperature differences on the optical axis, reducing focus drift, and ensuring that the lens can maintain focus stability when switching between day and night and when the ambient temperature changes, thus ensuring the clarity and continuity of long-distance monitoring.
[0024] Furthermore, the material of the third lens is plastic. Specifically, the second, third, fifth, and sixth lenses are all aspherical plastic lenses; the first and fourth lenses are both spherical glass lenses.
[0025] The beneficial effects of this embodiment are as follows: Through the glass-plastic hybrid structural design and the precise combination of different materials and spherical lenses, a day-night confocal effect with a focal length of 6mm is achieved. The use of plastic as the material for the third lens facilitates thermal optimization of the system, allowing the lens to maintain focal stability over a wide temperature range of -40℃ to 85℃, effectively resisting the effects of thermal expansion and contraction of the lens caused by harsh outdoor temperature differences. The spherical lens, made of glass, has the following advantages: stable refractive index, low coefficient of thermal expansion, and high mechanical strength. This ensures the stability of the system's optical reference and helps suppress focal length shift caused by temperature changes, improving lens reliability. The aspherical lens, made of plastic, has the following advantages: plastic is easy to precisely mold, allowing for flexible implementation of complex surface shapes. It can efficiently correct various aberrations such as spherical aberration, coma, and astigmatism, maintaining high image quality even at large apertures, while effectively reducing the number of lenses, simplifying the structure, and reducing weight.
[0026] The image-side surface of the fifth lens is aspherical, and its base spherical surface is convex. By introducing higher-order aspherical coefficients, this surface exhibits convexity near the optical axis and concave optical characteristics in the off-axis region, thereby effectively correcting higher-order spherical aberrations and aberrations of the system and improving imaging quality.
[0027] Furthermore, the lens satisfies the following relationships: Nd4 ≥ 1.6; 65 ≤ Vd4 ≤ 70; where Nd4 is the refractive index of the fourth lens and Vd4 is the Abbe coefficient of the fourth lens.
[0028] The beneficial effects of this embodiment are as follows: by satisfying the above relationship, it is beneficial to correct the focus of visible light and infrared light to the same reference, effectively solve the problem of focus shift and image blurring when switching between day and night in traditional lenses, ensure that both daytime color imaging and nighttime infrared black and white imaging can remain clear and sharp, further enhance the day and night confocal performance of the lens, adapt to the all-weather, no-blind-spot long-distance monitoring needs in the field of security monitoring, and at the same time, with the glass-plastic hybrid structure and heatless design, comprehensively improve the imaging stability and consistency of the lens under different light and temperature environments.
[0029] Furthermore, the lens satisfies the following relationship: The refractive index Nd1 of the first lens satisfies the following relationship: 1.4≤Nd1≤1.6; The refractive index Nd2 of the second lens satisfies the following relationship: 1.4≤Nd2≤1.6; The refractive index Nd3 of the third lens satisfies the following relationship: 1.4 ≤ Nd3 ≤ 1.6; The refractive index Nd5 of the fifth lens satisfies the following relationship: 1.5 ≤ Nd5 ≤ 1.7; The refractive index Nd6 of the sixth lens satisfies the following relationship: 1.4≤Nd6≤1.6.
[0030] The beneficial effects of this embodiment are as follows: by satisfying the above-mentioned relationship, the refractive index range of each lens is reasonably configured, so that the refractive index gradient between each lens transitions smoothly. This enables them to work together to achieve matching of light deflection and transmission in the visible and near-infrared bands, further balancing the system's spherical aberration, chromatic aberration, and band dispersion, and improving the imaging quality under large aperture conditions. At the same time, it makes the refractive index change of the optical system more controllable at different wavelengths, enhances the day and night confocal effect, ensures clear and stable imaging during both day and night, and is conducive to improving optical stability in a wide temperature environment, enabling the lens to maintain high precision and all-weather long-distance monitoring capabilities even in harsh outdoor environments.
[0031] Furthermore, the lens satisfies the following relationship: The Abbe coefficient Vd1 of the first lens satisfies the following relationship: 61.2 ≤ Vd1 ≤ 67.2; The Abbe coefficient Vd2 of the second lens satisfies the following relationship: 53.7≤Vd2≤58.7; The Abbe coefficient Vd3 of the third lens satisfies the following relationship: 53.7≤Vd3≤58.7; The Abbe coefficient Vd5 of the fifth lens satisfies the following relationship: 22≤Vd5≤26; The Abbe coefficient Vd6 of the sixth lens satisfies the following relationship: 53.7≤Vd6≤58.7.
[0032] The beneficial effects of this embodiment are as follows: by satisfying the above-mentioned relationship, the Abbe coefficient range of each lens is precisely defined. Combined with the refractive index configuration and positive and negative refractive index characteristics of each lens, the dispersion error of the optical system can be efficiently corrected, especially the chromatic aberration in the visible and near-infrared bands. This effectively suppresses color shift and edge chromatic aberration during large-aperture imaging, improving the clarity and color consistency of the image quality. At the same time, the reasonable combination of different Abbe coefficients can work synergistically with the glass-plastic hybrid structure and the anechoic design to further optimize the stability of the optical system, reduce the impact of temperature changes and light switching on the dispersion correction effect, and ensure that the lens can maintain excellent dispersion correction performance in a wide temperature range and under different day and night lighting conditions.
[0033] Furthermore, the lens satisfies the following relationship: The focal length f2 of the second lens satisfies the following relationship: -8.3 ≤ f2 ≤ -7.3; The focal length f3 of the third lens satisfies the following relationship: 7.6≤f3≤8.8; The focal length f4 of the fourth lens satisfies the following relationship: 7.1≤f4≤8.7; The focal length f5 of the fifth lens satisfies the following relationship: -7.6 ≤ f5 ≤ -5.2; The focal length f6 of the sixth lens satisfies the following relationship: 11≤f6≤12.
[0034] The beneficial effects of this embodiment are as follows: by satisfying the above relationship, the focal lengths of each lens are accurately matched and reasonably allocated, so that the positive and negative refractive index lenses form a stable and efficient optical combination, and the focal lengths of each lens are adapted to the imaging requirements of visible light and infrared dual bands, improving the light convergence accuracy and imaging consistency, ensuring that the system achieves stable day and night confocality at a focal length of 6mm, and avoiding focus shift during day and night switching.
[0035] Furthermore, the lens satisfies the following relationship: 0.2 < BFL / TTL < 0.3; where BFL is the optical back focal length of the lens, and TTL is the total optical length of the lens.
[0036] The beneficial effects of this embodiment are as follows: by satisfying the above-mentioned relationship, a compact lens structure design can be achieved, effectively reducing the overall size of the lens and facilitating outdoor installation and deployment. A reasonable BFL / TTL ratio can optimize the transmission path of light within the lens, ensuring that visible light and infrared light are precisely converged onto the same imaging plane after refraction by each lens.
[0037] Furthermore, the lens satisfies the following relationship: 0.82 < BFL / f < 1.02; where BFL is the optical back focal length of the lens and f is the focal length of the lens.
[0038] The beneficial effect of this embodiment is that by satisfying the above relationship, the back focal length of the lens is more reasonably matched with the overall focal length, thus ensuring the stability of the imaging plane position.
[0039] For ease of description, in Tables 1 to 3: surface number 1 and surface number 2 are the object-side and image-side surfaces of the first lens, respectively; surface number 3 and surface number 4 are the object-side and image-side surfaces of the second lens, respectively; surface number 5 is the surface of the aperture stop. Surface number 6 and surface number 7 are the object-side and image-side surfaces of the third lens, respectively; surface number 8 and surface number 9 are the object-side and image-side surfaces of the fourth lens, respectively; surface number 10 and surface number 11 are the object-side and image-side surfaces of the fifth lens, respectively; surface number 12 and surface number 13 are the object-side and image-side surfaces of the sixth lens, respectively; surface number 14 and surface number 15 are the object-side and image-side surfaces of the protective glass; surface number 16 is the surface of the imaging plane.
[0040] Please refer to the optical structure of Example 1. Figure 1The specific parameters of this embodiment 1 are shown in Table 1 below. In this embodiment 1, the lens focal length f=6.0mm, the light transmission FNO=1.6, the field of view FOV=64°, the target surface size IMH=6.8mm, and the total length TTL=22mm.
[0041] Table 1 - Lens Parameter Table for Example 1
[0042] According to Table 1, the conditional expression of Embodiment 1 of the present invention can be read as follows: (1) The refractive index of the first lens is Nd1=1.5; the Abbe coefficient of the first lens is Vd1=64.2; (2) The refractive index of the second lens is Nd2=1.5; the Abbe coefficient of the second lens is Vd2=55.7; the focal length of the second lens is f2=-7.8; (3) The refractive index of the third lens is Nd3=1.5; the Abbe coefficient of the third lens is Vd3=55.7; the focal length of the third lens is f3=8.3; (4) The refractive index of the fourth lens is Nd4=1.6; the Abbe coefficient of the fourth lens is Vd4=68.3; the focal length of the fourth lens is f4=8.2; (5) The refractive index of the fifth lens is Nd5=1.6; the Abbe coefficient of the fifth lens is Vd5=24; the focal length of the fifth lens is f5=-6.1; (6) The refractive index of the sixth lens is Nd6=1.5; the Abbe coefficient of the sixth lens is Vd6=55.7; the focal length of the sixth lens is f6=11.5.
[0043] Table 2 - Arrangement of Aspherical Coefficients of Various Aspherical Lenses in Example 1
[0044] In Example 1, by setting the second, third, fifth, and sixth lenses as aspherical lenses, and by combining each aspherical surface with precise high-order coefficients, various aberrations such as spherical aberration, coma, astigmatism, field curvature, and distortion can be effectively corrected, thereby improving the lens imaging effect.
[0045] Please refer to the optical structure of Example 2. Figure 6 The specific parameters of this embodiment 2 are shown in Table 3 below. In this embodiment 2, the lens focal length f=6.0mm, the light transmission FNO=1.6, the field of view FOV=64°, the target surface size IMH=6.8mm, and the total length TTL=22mm.
[0046] Table 3 - Lens Parameter Table for Example 2
[0047] According to Table 3, the conditional expression of Embodiment 2 of the present invention can be read as follows: (1) The refractive index of the first lens is Nd1=1.5; the Abbe coefficient of the first lens is Vd1=64.2; (2) The refractive index of the second lens is Nd2=1.5; the Abbe coefficient of the second lens is Vd2=55.7; the focal length of the second lens is f2=-7.8; (3) The refractive index of the third lens is Nd3=1.5; the Abbe coefficient of the third lens is Vd3=55.7; the focal length of the third lens is f3=8.1; (4) The refractive index of the fourth lens is Nd4=1.6; the Abbe coefficient of the fourth lens is Vd4=68.3; the focal length of the fourth lens is f4=7.6; (5) The refractive index of the fifth lens is Nd5=1.6; the Abbe coefficient of the fifth lens is Vd5=25.8; the focal length of the fifth lens is f5=-5.7; (6) The refractive index of the sixth lens is Nd6=1.5; the Abbe coefficient of the sixth lens is Vd6=55.7; the focal length of the sixth lens is f6=11.5.
[0048] Table 4 - Arrangement of Aspherical Coefficients of Various Aspherical Lenses in Example 2
[0049] In Example 2, by setting the second, third, fifth, and sixth lenses as aspherical lenses, and by combining each aspherical surface shape with precise high-order coefficients, various aberrations such as spherical aberration, coma, astigmatism, field curvature, and distortion can be effectively corrected, thereby improving the lens imaging effect.
[0050] Table 5 - Lens Parameters for Examples 1 and 2
[0051] The following is an explanation of the various figures in Examples 1 and 2: Figure 2 The image shows the MTF (Medium Transfer Function) of Example 1 in the visible light band. As can be seen from the image, the contrast ratio across the entire field of view is greater than 0.69 at a spatial frequency of 83 lp / mm. This indicates that the lens exhibits excellent and consistent contrast performance across the entire field of view, possessing outstanding spatial resolution and imaging resolution, clearly reproducing details, and meeting the stringent requirements of high-resolution imaging systems.
[0052] Figure 3The image shows the MTF (Modulation Transfer Function) of Example 1 in the near-infrared band. As can be seen from the image, the contrast ratio across the entire field of view is greater than 0.63 at a spatial frequency of 83 lp / mm. This indicates that the lens exhibits excellent and consistent contrast performance across the entire field of view, possessing outstanding spatial resolution and imaging resolution, clearly reproducing details, and meeting the stringent requirements of high-resolution imaging systems.
[0053] Figure 4 This is a chromatic aberration diagram of Example 1. As can be seen from the diagram, the chromatic aberration of the lens of the present invention is less than 4.1 μm, which achieves efficient correction and precise control of chromatic aberration, effectively suppresses the imaging shift of different wavelengths of light on the image plane, significantly improves the color reproduction and color consistency of the system, and ensures that the image is realistic and natural with no obvious color cast.
[0054] Figure 5 This is the relative illumination diagram for Example 1. As can be seen from the diagram, the relative illumination across the entire field of view is greater than 50%, which effectively improves the light energy utilization and imaging brightness uniformity of the optical system, avoids obvious dark corners in the image, and improves the overall imaging quality.
[0055] Figure 7 The image shows the MTF (Medium Transfer Function) of Example 2 in the visible light band. As can be seen from the image, the contrast ratio across the entire field of view is greater than 0.72 at a spatial frequency of 83 lp / mm. This indicates that the lens exhibits excellent and consistent contrast performance across the entire field of view, possessing outstanding spatial resolution and imaging resolution, clearly reproducing details, and meeting the stringent requirements of high-resolution imaging systems.
[0056] Figure 8 The image shows the MTF (Modulation Transfer Function) of Example 2 in the near-infrared band. As can be seen from the image, the contrast ratio across the entire field of view is greater than 0.48 at a spatial frequency of 83 lp / mm. This indicates that the lens exhibits excellent and consistent contrast performance across the entire field of view, possessing outstanding spatial resolution and imaging resolution, clearly reproducing details, and meeting the stringent requirements of high-resolution imaging systems.
[0057] Figure 9 This is the chromatic aberration diagram of Example 2. As can be seen from the diagram, the chromatic aberration of the lens of the present invention is less than 2.8 μm, which achieves efficient correction and precise control of chromatic aberration, effectively suppresses the imaging shift of different wavelengths of light on the image plane, significantly improves the color reproduction and color consistency of the system, and ensures that the image is realistic and natural with no obvious color cast.
[0058] Figure 10This is the relative illumination diagram for Example 2. As can be seen from the diagram, the relative illumination across the entire field of view is greater than 52%, which effectively improves the light energy utilization and imaging brightness uniformity of the optical system, avoids obvious dark corners in the image, and improves the overall imaging quality.
[0059] On the other hand, now refer to Figure 11 A schematic diagram of the structure of the electronic device A according to the present invention will be given. Figure 11 This is a schematic diagram of an electronic device (camera) for a camera optical system using one of the visible light and infrared dual-lens lenses used for long-distance monitoring according to Examples 1 to 2.
[0060] exist Figure 11 In the figures, reference numeral A2 indicates the main body of the electronic device, and reference numeral A1 indicates any one of the camera optical systems (interchangeable lenses) including the visible light and infrared dual-lens lenses used for long-distance monitoring according to embodiments 1 to 2. Reference numeral A3 indicates an image sensor (photoelectric conversion element) such as a CMOS image sensor or a CCD image sensor, which is built into the camera body A2 and receives light (the optical image formed by the camera optical system A1) from the camera optical system A1 and performs photoelectric conversion.
[0061] By using a visible light and infrared dual-lens lens for long-distance monitoring according to any one of Examples 1 to 2 in electronic devices such as digital still cameras, electronic devices with high optical performance can be obtained.
[0062] Each example can provide electronic devices with high optical performance.
[0063] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims will be given the broadest interpretation to cover all such modifications and equivalent structures and functions.
Claims
1. A dual-lens lens for long-distance monitoring, characterized in that, It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side; The object-side surface of the first lens is a plane, and the image-side surface is a plane; The second lens has a negative refractive index, and the object side of the second lens is convex, while the image side is concave. The third lens has a positive refractive index, and the object side and the image side of the third lens are both convex. The fourth lens has a positive refractive index, and the object side and the image side of the fourth lens are both convex. The fifth lens has a negative refractive index, and the object side of the fifth lens is concave, while the image side is convex. The sixth lens has a positive refractive index, and the object side and the image side of the sixth lens are both convex.
2. The visible light and infrared dual-lens lens for long-distance monitoring as described in claim 1, characterized in that, The third lens is made of plastic.
3. A visible light and infrared dual-lens lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: Nd4 ≥ 1.6; 65 ≤ Vd4 ≤ 70; Wherein, Nd4 is the refractive index of the fourth lens, and Vd4 is the Abbe coefficient of the fourth lens.
4. A visible light and infrared dual-light lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: The refractive index Nd1 of the first lens satisfies the following relationship: 1.4≤Nd1≤1.6; The refractive index Nd2 of the second lens satisfies the following relationship: 1.4≤Nd2≤1.6; The refractive index Nd3 of the third lens satisfies the following relationship: 1.4 ≤ Nd3 ≤ 1.6; The refractive index Nd5 of the fifth lens satisfies the following relationship: 1.5 ≤ Nd5 ≤ 1.7; The refractive index Nd6 of the sixth lens satisfies the following relationship: 1.4≤Nd6≤1.
6.
5. A visible light and infrared dual-lens lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: The Abbe coefficient Vd1 of the first lens satisfies the following relationship: 61.2 ≤ Vd1 ≤ 67.2; The Abbe coefficient Vd2 of the second lens satisfies the following relationship: 53.7≤Vd2≤58.7; The Abbe coefficient Vd3 of the third lens satisfies the following relationship: 53.7≤Vd3≤58.7; The Abbe coefficient Vd5 of the fifth lens satisfies the following relationship: 22≤Vd5≤26; The Abbe coefficient Vd6 of the sixth lens satisfies the following relationship: 53.7≤Vd6≤58.
7.
6. A visible light and infrared dual-light lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: The focal length f2 of the second lens satisfies the following relationship: -8.3 ≤ f2 ≤ -7.3; The focal length f3 of the third lens satisfies the following relationship: 7.6≤f3≤8.8; The focal length f4 of the fourth lens satisfies the following relationship: 7.1≤f4≤8.7; The focal length f5 of the fifth lens satisfies the following relationship: -7.6 ≤ f5 ≤ -5.2; The focal length f6 of the sixth lens satisfies the following relationship: 11≤f6≤12.
7. A visible light and infrared dual-light lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: 0.2 < BFL / TTL < 0.3; Where BFL is the optical rear focal length of the lens, and TTL is the optical total length of the lens.
8. A visible light and infrared dual-light lens for long-distance monitoring as described in claim 1, characterized in that, The lens satisfies the following relationship: 0.82 < BFL / f < 1.02; Where BFL is the optical back focal length of the lens, and f is the focal length of the lens.
9. A visible light and infrared dual-lens lens for long-distance monitoring as described in claim 1, characterized in that, The image-side surface of the fifth lens is aspherical, while its base spherical surface is convex.
10. An electronic device, characterized in that, A visible light and infrared dual-lens lens for long-distance monitoring according to any one of claims 1-9; and An image sensor is configured to receive images formed by the dual-lens visible light and thermal imaging lens for long-range monitoring.