Ultra-large aperture ultra-wide angle infrared lenses and electronic devices

Abstract

This invention discloses an ultra-large aperture ultra-wide-angle infrared lens and electronic device. The ultra-large aperture ultra-wide-angle infrared lens includes, along the optical axis from the object side to the image side, a first lens, a second lens, a third lens, and a fourth lens. Each of the first to fourth lenses includes an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing imaging light to pass through. The aperture F#, field of view (FOV), and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens satisfy: F#*TAN(FOV / 2)*SQRT(f′ / 100)≥0.24. The ultra-large aperture ultra-wide-angle infrared lens and electronic device of this invention can achieve ultra-large aperture and ultra-wide-angle performance, and has excellent resolution, meeting the needs of various application scenarios.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, and in particular to an ultra-large aperture ultra-wide-angle infrared lens and electronic device. Background Technology

[0002] With the development of science and technology, infrared lenses can be used for facial recognition, thermal imaging, and infrared monitoring, thus finding wide application in mobile phones, drones, and smart homes. However, the complexity of these applications necessitates an infrared lens with an ultra-large aperture and ultra-wide field of view to meet the stringent requirements of complex environments. Summary of the Invention

[0003] In view of the above problems, the purpose of this invention is to provide an ultra-large aperture ultra-wide-angle infrared lens and electronic device that can be used in complex scenarios and meet the demanding requirements of complex usage environments.

[0004] This invention provides an ultra-large aperture ultra-wide-angle infrared lens, which includes a first lens, a second lens, a third lens, and a fourth lens sequentially along the optical axis from the object side to the image side; each of the first lens to the fourth lens includes an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing imaging light to pass through; the aperture F#, field of view FOV, and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens satisfy: F#*TAN(FOV / 2)*SQRT(f′ / 100)≥0.24.

[0005] Optionally, the first lens has negative optical power, and the second, third, and fourth lenses have positive optical power.

[0006] Optionally, the image-side sagitta S2 of the first lens and the center thickness H1 of the first lens satisfy: 0.4≤S2 / H1≤0.55.

[0007] Optionally, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: ABS(f2-f3)≤0.5.

[0008] Optionally, the focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens and the focal length f1 of the first lens satisfy: 1.6≤f1 / f′≤2.

[0009] Optionally, the maximum absolute values ​​of the object-side sagittal height and the image-side sagittal height of the second to the fourth lenses satisfy: MAX(ABS(S3), ABS(S4), ...ABS(S8))≤0.35.

[0010] Optionally, the object-side sagitta S1 of the first lens satisfies: 0.3≤S1≤0.55.

[0011] Optionally, the focal length f2 of the second lens satisfies: 1.5≤f2≤3.

[0012] Optionally, the object-side sagitta S3 of the second lens satisfies: ABS(S3)≤0.05.

[0013] The present invention also provides an electronic device, including the above-mentioned ultra-large aperture ultra-wide-angle infrared lens.

[0014] The ultra-large aperture ultra-wide-angle infrared lens and electronic device provided by this invention have an aperture F#, field of view (FOV), and focal length f′ that satisfy: F#*TAN(FOV / 2)*SQRT(f′ / 100)≥0.24. This helps to balance the aperture, field of view, and focal length, thereby preventing any parameter from deviating from the normal range. Furthermore, the aperture F# is set to be smaller than that of existing lenses, and the field of view (FOV) is set to be larger than that of existing lenses, for example, F#<1.4 and FOV=124°. This achieves an ultra-large aperture ultra-wide-angle lens, which can be used in complex scenes and meet the demanding requirements of complex usage environments. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 1 of this application is shown.

[0017] Figures 2 to 4 The distortion diagram, MTF curve, and relative illumination versus Y-field angle diagram of the ultra-large aperture ultra-wide-angle infrared lens of Example 1 are shown respectively.

[0018] Figure 5 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 2 of this application is shown.

[0019] Figures 6 to 8 The distortion diagram, MTF curve, and relative illumination versus Y-field angle diagram of the ultra-large aperture ultra-wide-angle infrared lens of Example 2 are shown respectively.

[0020] Figure 9 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 3 of this application is shown.

[0021] Figures 10 to 12 The distortion diagram, MTF curve, and relative illumination versus Y-field angle diagram of the ultra-large aperture ultra-wide-angle infrared lens of Example 3 are shown respectively. Detailed Implementation

[0022] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of preferred embodiments with reference to the accompanying drawings. Through the description of the specific embodiments, a more in-depth and specific understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the present invention; some well-known parts may not be shown. In the various drawings, the same elements are represented by similar reference numerals. For clarity, the various parts in the drawings are not necessarily drawn strictly to scale.

[0023] It is important to understand that the terms "first," "second," "third," "fourth," etc., are used merely to distinguish elements or circuits with similar properties, and do not indicate or imply relative importance or a specific order. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the listed elements but also other elements not expressly listed.

[0024] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0025] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] The features, principles and other aspects of this application are described in detail below.

[0028] According to an exemplary embodiment of this application, the ultra-large aperture ultra-wide-angle infrared lens includes a first lens P1, a second lens P2, a third lens P3, and a fourth lens P4 from the object side to the image side; each of the first lens P1 to the fourth lens P4 includes an object side facing the object side and allowing imaging light to pass through, and an image side facing the image side and allowing imaging light to pass through; the aperture F#, field of view FOV, and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens satisfy: F#*TAN(FOV / 2)*SQRT(f′ / 100)≥0.24. The ultra-large aperture ultra-wide-angle infrared lens of this embodiment includes four lenses. By rationally allocating the optical power and spacing of each lens, and by controlling the aperture F#, field of view (FOV), and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens, it is possible to balance the aperture, field of view, and focal length, thereby preventing any parameter from deviating from the normal range. Furthermore, by setting the aperture F# to be smaller than that of existing lenses, and the field of view (FOV) to be larger than that of existing lenses (e.g., F# < 1.4 and FOV = 124°), an ultra-large aperture ultra-wide-angle lens is achieved, making it suitable for complex scenes and meeting the demanding requirements of complex usage environments. Specifically, setting the aperture F# to be smaller, such as F# < 1.4, achieves an ultra-large aperture, meeting the need for rapid photography in low-light conditions; setting the field of view to be larger, such as 124°, achieves an ultra-wide-angle lens, giving the device a wider field of view.

[0029] In an exemplary embodiment, the ultra-wide-angle infrared lens according to this application has a first lens P1 with negative optical power, and a second lens P2, a third lens P3, and a fourth lens P4 with positive optical power. By setting the negative and positive focal lengths of the first lens P1 to the fourth lens P4, image quality can be improved, astigmatism and distortion can be corrected, and a greater optical path length and system correction capability can be provided, contributing to high-quality image capture and imaging effects. Simultaneously, the number of lenses used is small, making it easy to manufacture and resulting in lower costs; the total optical length can be less than 3.8mm, meeting the miniaturization requirements of camera modules.

[0030] In an exemplary embodiment, the ultra-wide-angle infrared lens according to this application further includes an IR filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface 61.

[0031] In an exemplary embodiment, the ultra-large aperture ultra-wide-angle infrared lens according to this application satisfies 0.4 ≤ S2 / H1 ≤ 0.55; wherein, the image-side sag of the first lens P1 is S2, and the center thickness of the first lens P1 is H1. Satisfying 0.4 ≤ S2 / H1 ≤ 0.55, by controlling the image-side sag S2 and the center thickness H1 of the first lens P1 within a suitable range, manufacturability can be improved.

[0032] In an exemplary embodiment, the ultra-wide-angle infrared lens according to this application satisfies ABS(f2-f3)≤0.5; wherein the focal length of the second lens P2 is f2 and the focal length of the third lens P3 is f3. Satisfying ABS(f2-f3)≤0.5, by controlling the difference in focal length between the second lens P2 and the third lens P3, avoids excessive light deflection angles that could lead to severe primary aberrations, thus improving resolution.

[0033] In an exemplary embodiment, the ultra-large aperture ultra-wide-angle infrared lens according to this application satisfies 1.6 ≤ f1 / f′ ≤ 2; where f′ is the focal length of the ultra-large aperture ultra-wide-angle infrared lens and f1 is the focal length of the first lens P1. Satisfying 1.6 ≤ f1 / f′ ≤ 2, by controlling the ratio of the focal length f1 of the first lens P1 to the focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens within a reasonable range, is beneficial for converging large-angle light and achieving an ultra-wide-angle perspective.

[0034] In an exemplary embodiment, the ultra-wide-angle infrared lens according to this application satisfies MAX(ABS(S3), ABS(S4), ... ABS(S8)) ≤ 0.35; where MAX(ABS(S3), ABS(S4), ... ABS(S8)) represents the maximum absolute value of the object-side sagitta and image-side sagitta of the second lens P2 to the fourth lens P4, wherein the object-side sagitta of the second lens P2 is S3, the image-side sagitta of the second lens P2 is S4, ..., the object-side sagitta of the fourth lens P4 is S7, and the image-side sagitta of the fourth lens P4 is S8. Satisfying MAX(ABS(S3), ABS(S4), ... ABS(S8)) ≤ 0.35, by controlling the sagitta of the second lens P2 to the fourth lens P4 to be less than a certain value, enhances the manufacturability of the lens.

[0035] In an exemplary embodiment, the ultra-wide-angle infrared lens with a large aperture according to this application can satisfy 0.3≤S1≤0.55; wherein, the object-side sag of the first lens P1 is S1. Satisfying 0.3≤S1≤0.55, by controlling the object-side sag S1 of the first lens P1 to be less than a certain value, can help converge large-angle light and achieve an ultra-wide-angle view.

[0036] In an exemplary embodiment, the ultra-large aperture ultra-wide-angle infrared lens according to this application satisfies 1.5≤f2≤3; wherein, the focal length of the second lens P2 is f2. Satisfying 1.5≤f2≤3, by controlling the focal length f2 of the second lens P2 to be less than a certain value, can help converge the light from the rear group and reduce the lens height.

[0037] In an exemplary embodiment, the ultra-large aperture ultra-wide-angle infrared lens according to this application can satisfy ABS(S3)≤0.05; wherein, the object-side sagitta of the second lens P2 is S3. Satisfying ABS(S3)≤0.05, by controlling the object-side sagitta S3 of the second lens P2 to be less than a certain value, can avoid the incident angle of the front group light entering the rear group being too large, resulting in serious primary aberrations, which is beneficial to improving resolution.

[0038] In an exemplary embodiment, the ultra-large aperture ultra-wide-angle infrared lens according to this application further includes an aperture stop STO, which is disposed between the first lens P1 and the second lens P2 to further improve overall performance. In other exemplary embodiments, the aperture stop STO may be disposed between other lenses.

[0039] Based on the same inventive concept, the electronic device according to the exemplary embodiments of this application includes the aforementioned ultra-large aperture ultra-wide-angle infrared lens. The electronic device includes, but is not limited to, smartphones, tablets, laptops, gimbal cameras, surveillance cameras, and other imaging devices. Implementation of this electronic device can be found in the embodiments of the ultra-large aperture ultra-wide-angle infrared lens; repeated details will not be elaborated further.

[0040] However, those skilled in the art will understand that the number of lenses constituting the optical imaging lens can be varied to obtain the various results and advantages described herein without departing from the technical solutions claimed in this application. For example, although four lenses are described as an example in the embodiments, the optical imaging lens is not limited to including four lenses. If desired, the optical imaging lens may also include other numbers of lenses.

[0041] The following describes in further detail, with reference to the accompanying drawings, specific embodiments of the ultra-large aperture ultra-wide-angle infrared lens applicable to the above-described embodiments.

[0042] Example 1

[0043] The following is for reference Figure 1 This application describes an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 1 of this application. Figure 1 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 1 of this application is shown.

[0044] like Figure 1 As shown, the ultra-wide-angle infrared lens with a large aperture includes, in order from the object side to the image side, a first lens P1, an aperture stop STO, a second lens P2, a third lens P3, a fourth lens P4, an IR filter, and an imaging plane 61.

[0045] The first lens P1 has negative optical power, with its object-side surface 11 being convex and its image-side surface 12 being concave. The second lens P2 has positive optical power, with its object-side surface 21 being concave and its image-side surface 22 being convex. The third lens P3 has positive optical power, with its object-side surface 31 being convex and its image-side surface 32 being convex. The fourth lens P4 has positive optical power, with its object-side surface 41 being convex and its image-side surface 42 being concave. The filter IR has an object-side surface 51 and an image-side surface 52. Light from the object passes sequentially through the object-side and image-side surfaces of the first lens P1, the fourth lens P4, and the filter IR, and is finally imaged on the imaging surface 61.

[0046] Table 1 shows the basic parameters of the ultra-large aperture ultra-wide-angle infrared lens of Example 1, where the units for radius of curvature and thickness are millimeters (mm).

[0047] Table 1:

[0048]

[0049] In Example 1, the object-side surface and image-side surface of any one of the first lens P1 to the fourth lens P4 are both even-order aspherical surfaces, and the surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0050] (1)

[0051] Where z is the distance vector from the vertex of the aspherical surface at a height of r along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; A2, A4, A6, A8, A 10 A 12 A 14 and A 16 These are the correction coefficients for the second, fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth orders of aspherical surfaces, respectively.

[0052] Table 2 lists the higher-order coefficients A2, A4, A6, A8, and A6 that can be used for each aspherical mirror in Example 1. 10 A 12 A 14 and A 16 .

[0053] Table 2:

[0054]

[0055] In this embodiment, based on the optical power distribution of the first lens P1 to the fourth lens P4 in the table above, and the reasonable allocation of the optical power, spacing, and refractive index of each lens, an ultra-large aperture ultra-wide-angle lens can be achieved. Specifically, the aperture of the ultra-large aperture ultra-wide-angle infrared lens is f / 1.35, and the field of view is 124°. The total optical length of existing mobile phone lenses is typically between 3mm and 5mm. In this embodiment, the total optical length of the ultra-large aperture ultra-wide-angle infrared lens is 3.6mm, achieving miniaturization. Furthermore, the focal length of the ultra-large aperture ultra-wide-angle infrared lens in this embodiment is 0.92mm, the operating wavelength is 920-960nm, and the imaging circle diameter is 2.36mm. The relationship between the aperture F#, field of view (FOV), and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens is F#*TAN(FOV / 2)*SQRT(f′ / 100)=0.243; the relationship between the image-side sag S2 and center thickness H1 of the first lens P1 is: S2 / H1=0.522; the relationship between the focal length f2 of the second lens P2 and the focal length f3 of the third lens P3 is: ABS(f2-f3)=0.03; the relationship between the focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens and the focal length of the first lens P1 is... The relationship between f1 is: f1 / f′=1.79; the relationship between the maximum absolute values ​​of the object-side sagitta and image-side sagitta of the second lens P2 to the fourth lens P4 is: MAX(ABS(S3), ABS(S4), ...ABS(S8))=0.30; the relationship between the object-side sagitta S1 of the first lens P1 is: S1=0.44; the relationship between the focal length f2 of the second lens P2 is: f2=2.07; the relationship between the object-side sagitta S3 of the second lens P2 is: ABS(S3)=0.02.

[0056] Figure 2 The distortion diagram of the ultra-large aperture ultra-wide-angle infrared lens of Example 1 is shown. The distortion is less than 35%, which is very small. Figure 3 The MTF curve of the ultra-wide-angle infrared lens of Example 1 is shown. The MTF (Modulation Transfer Function) curve is the change of the lens's ability to reproduce the details of the subject onto the image plane as a function of spatial frequency. At a spatial frequency of 50 lp / mm, the minimum MTF is greater than 0.2, indicating good resolution. Figure 4 The diagram shows the relative illumination and Y-field of view of the ultra-large aperture ultra-wide-angle infrared lens of Example 1. The relative illumination is greater than 0.4, and the image illumination is uniform. According to... Figures 2 to 4 As can be seen, the ultra-large aperture ultra-wide angle infrared lens given in Example 1 can achieve good imaging quality, realize ultra-large aperture and ultra-wide angle performance, and has excellent resolution, meeting the needs of various application scenarios.

[0057] Example 2

[0058] The following is for reference Figure 5 This application describes an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 2 of this application. Figure 5 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 2 of this application is shown. In this embodiment, for the sake of brevity, descriptions similar to those in Embodiment 1 are omitted.

[0059] like Figure 5 As shown, the ultra-wide-angle infrared lens with a large aperture includes, in order from the object side to the image side, a first lens P1, an aperture stop STO, a second lens P2, a third lens P3, a fourth lens P4, an IR filter, and an imaging plane 61.

[0060] The first lens P1 has negative optical power, with its object-side surface 11 being convex and its image-side surface 12 being concave. The second lens P2 has positive optical power, with its object-side surface 21 being convex and its image-side surface 22 being convex. The third lens P3 has positive optical power, with its object-side surface 31 being convex and its image-side surface 32 being convex. The fourth lens P4 has positive optical power, with its object-side surface 41 being convex and its image-side surface 42 being concave. The filter IR has an object-side surface 51 and an image-side surface 52. Light from the object passes sequentially through the object-side and image-side surfaces of the first lens P1, the fourth lens P4, and the filter IR, and is finally imaged on the imaging surface 61.

[0061] Table 3 shows the basic parameters of the ultra-large aperture ultra-wide-angle infrared lens of Example 2, where the units for radius of curvature and thickness are millimeters (mm).

[0062] Table 3:

[0063]

[0064] Table 4 shows the higher-order coefficients that can be used for each aspherical mirror in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0065] Table 4:

[0066]

[0067] In this embodiment, based on the optical power distribution of the first lens P1 to the fourth lens P4 in the table above, and the reasonable allocation of the optical power, spacing, and refractive index of each lens, an ultra-large aperture ultra-wide-angle lens can be achieved. Specifically, the aperture of the ultra-large aperture ultra-wide-angle infrared lens is f / 1.34, and the field of view is 124°. The total optical length of existing mobile phone lenses is typically between 3mm and 5mm. In this embodiment, the total optical length of the ultra-large aperture ultra-wide-angle infrared lens is 3.7mm, achieving miniaturization. Furthermore, the focal length of the ultra-large aperture ultra-wide-angle infrared lens in this embodiment is 0.93mm, the operating wavelength is 920-960nm, and the imaging circle diameter is 2.5mm. The relationship between the aperture F#, field of view (FOV), and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens is F#*TAN(FOV / 2)*SQRT(f′ / 100)=0.243; the relationship between the image-side sag S2 and center thickness H1 of the first lens P1 is S2 / H1=0.549; the relationship between the focal length f2 of the second lens P2 and the focal length f3 of the third lens P3 is ABS(f2-f3)=0.03; the relationship between the focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens and the focal length of the first lens P1 is... The relationship between f1 is: f1 / f′=1.76; the relationship between the maximum absolute values ​​of the object-side sagitta and image-side sagitta of the second lens P2 to the fourth lens P4 is: MAX(ABS(S3), ABS(S4), ...ABS(S8))=0.29; the relationship between the object-side sagitta S1 of the first lens P1 is: S1=0.37; the relationship between the focal length f2 of the second lens P2 is: f2=2.00; the relationship between the object-side sagitta S3 of the second lens P2 is: ABS(S3)=0.01.

[0068] Figure 6 The distortion diagram of the ultra-large aperture ultra-wide-angle infrared lens of Example 2 is shown. The distortion is less than 30%, which is very small. Figure 7 The MTF curve of the ultra-wide-angle infrared lens of Example 2 is shown. The MTF (Modulation Transfer Function) curve is the change of the lens's ability to reproduce the details of the subject onto the image plane as a function of spatial frequency. At a spatial frequency of 50 lp / mm, the minimum MTF is greater than 0.2, indicating good resolution. Figure 8 The diagram shows the relative illumination and Y-field of view of the ultra-large aperture ultra-wide-angle infrared lens of Example 2. The relative illumination is greater than 0.39, and the image illumination is uniform. According to... Figures 6 to 8 As can be seen, the ultra-large aperture ultra-wide angle infrared lens given in Example 2 can achieve good imaging quality, realize ultra-large aperture and ultra-wide angle performance, and has excellent resolution, meeting the needs of various application scenarios.

[0069] Example 3

[0070] The following is for reference Figure 9 This application describes an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 3 of this application. Figure 9 A schematic diagram of the optical structure of an ultra-large aperture ultra-wide-angle infrared lens according to Embodiment 3 of this application is shown. In this embodiment, for the sake of brevity, descriptions similar to those in Embodiment 1 are omitted.

[0071] like Figure 9 As shown, the ultra-wide-angle infrared lens with a large aperture includes, in order from the object side to the image side, a first lens P1, an aperture stop STO, a second lens P2, a third lens P3, a fourth lens P4, an IR filter, and an imaging plane 61.

[0072] The first lens P1 has negative optical power, with its object-side surface 11 being convex and its image-side surface 12 being concave. The second lens P2 has positive optical power, with its object-side surface 21 being convex and its image-side surface 22 being convex. The third lens P3 has positive optical power, with its object-side surface 31 being convex and its image-side surface 32 being convex. The fourth lens P4 has positive optical power, with its object-side surface 41 being convex and its image-side surface 42 being concave. The filter IR has an object-side surface 51 and an image-side surface 52. Light from the object passes sequentially through the object-side and image-side surfaces of the first lens P1, the fourth lens P4, and the filter IR, and is finally imaged on the imaging surface 61.

[0073] Table 5 shows the basic parameters of the ultra-large aperture ultra-wide-angle infrared lens of Example 3, where the units for radius of curvature and thickness are millimeters (mm).

[0074] Table 5:

[0075]

[0076] Table 6 shows the higher-order coefficients that can be used for each aspherical mirror in Example 3, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0077] Table 6:

[0078]

[0079] In this embodiment, based on the optical power distribution of the first lens P1 to the fourth lens P4 in the table above, and the reasonable allocation of the optical power, spacing, and refractive index of each lens, an ultra-large aperture ultra-wide-angle lens can be achieved. Specifically, the aperture of the ultra-large aperture ultra-wide-angle infrared lens is f / 1.35, and the field of view is 124°. The total optical length of existing mobile phone lenses is typically between 3mm and 5mm. The total optical length of the ultra-large aperture ultra-wide-angle infrared lens in this embodiment is 3.65mm, achieving miniaturization. Furthermore, the focal length of the ultra-large aperture ultra-wide-angle infrared lens in this embodiment is 0.92mm, the operating wavelength is 920-960nm, and the imaging circle diameter is 2.4mm. The relationship between the aperture F#, field of view (FOV), and focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens is F#*TAN(FOV / 2)*SQRT(f′ / 100)=0.243; the relationship between the image-side sag S2 and center thickness H1 of the first lens P1 is: S2 / H1=0.515; the relationship between the focal length f2 of the second lens P2 and the focal length f3 of the third lens P3 is: ABS(f2-f3)=0.18; the relationship between the focal length f′ of the ultra-large aperture ultra-wide-angle infrared lens and the focal length of the first lens P1... The relationship between f1 is: f1 / f′=1.76; the relationship between the maximum absolute values ​​of the object-side sagitta and the image-side sagitta of the second lens P2 to the fourth lens P4 is: MAX(ABS(S3), ABS(S4), ...ABS(S8))=0.24; the relationship between the object-side sagitta S1 of the first lens P1 is: S1=0.40; the relationship between the focal length f2 of the second lens P2 is: f2=1.97; the relationship between the object-side sagitta S3 of the second lens P2 is: ABS(S3)=0.03.

[0080] Figure 10 The distortion diagram of the ultra-wide-angle infrared lens with a large aperture in Example 3 is shown. The distortion is less than 32%, which is very small. Figure 11 The MTF curve of the ultra-wide-angle infrared lens of Example 3 is shown. The MTF (Modulation Transfer Function) curve is the change of the lens’s ability to reproduce the details of the subject onto the image plane as a function of spatial frequency. At a spatial frequency of 50 lp / mm, the minimum MTF is greater than 0.2, indicating good resolution. Figure 12 The diagram shows the relative illumination and Y-field of view of the ultra-large aperture ultra-wide-angle infrared lens of Example 3. The relative illumination is greater than 0.3, and the image illumination is uniform. According to... Figures 10 to 12 As can be seen, the ultra-large aperture ultra-wide angle infrared lens given in Example 3 can achieve good imaging quality, realize ultra-large aperture and ultra-wide angle performance, and has excellent resolution, meeting the needs of various application scenarios.

[0081] In summary, Examples 1, 2, and 3 satisfy the relationships shown in Table 7.

[0082] Table 7:

[0083]

[0084] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An ultra-large aperture ultra-wide-angle infrared lens, characterized in that, The first lens, the second lens, the third lens and the fourth lens are sequentially arranged along the optical axis from the object side to the image side, wherein the lenses with refractive power are four, the first lens has negative refractive power, the second lens, the third lens and the fourth lens have positive refractive power; the object side surface of the first lens is convex and the image side surface is concave, the image side surface of the second lens is convex, the third lens is a double convex lens, the object side surface of the fourth lens is convex and the image side surface is concave; the first lens to the fourth lens each comprise an object side surface facing the object side and passing the imaging light and an image side surface facing the image side and passing the imaging light; The aperture F# of the super large aperture super wide-angle infrared lens, the field of view FOV and the focal length f' satisfy: F#*TAN(FOV / 2)*SQRT(f' / 100)≥0.24, and 1.34≤F#<1.4; The focal length f2 of the second lens and the focal length f3 of the third lens satisfy: ABS(f2-f3)≤0.5mm. The focal length f' of the super large aperture super wide-angle infrared lens and the focal length f1 of the first lens satisfy: 1.6≤f1 / f'≤2.

2. The ultra-large aperture ultra-wide-angle infrared lens according to claim 1, characterized in that, The first lens has negative refractive power, and the second lens, the third lens and the fourth lens have positive refractive power.

3. The ultra-large aperture ultra-wide-angle infrared lens according to claim 1, characterized in that, The image side surface height S2 of the first lens and the central thickness H1 of the first lens satisfy: 0.4≤S2 / H1≤0.

55.

4. The super-wide-angle infrared lens with super-aperture according to claim 1, characterized in that, The maximum value of the absolute values of the object side surface height and the image side surface height of the second lens to the fourth lens satisfy: MAX(ABS(S3), ABS(S4), ABS(S8))≤0.35mm.

5. The ultra-large aperture ultra-wide-angle infrared lens according to claim 1, characterized in that, The object side surface height S1 of the first lens satisfies: 0.3mm≤S1≤0.55mm.

6. The ultra-large aperture ultra-wide-angle infrared lens according to claim 1, characterized in that, The focal length f2 of the second lens satisfies: 1.5mm≤f2≤3mm.

7. The ultra-large aperture, ultra-wide angle infrared lens of claim 1, wherein, The object side surface height S3 of the second lens satisfies: ABS(S3)≤0.05mm.

8. An electronic device, comprising: The super large aperture super wide-angle infrared lens comprises the super large aperture super wide-angle infrared lens as claimed in any one of claims 1 to 7.

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