Lens and camera device

Abstract

The present invention discloses a lens and a camera device, which are composed of a first negative power lens, a first positive power lens, a second positive power lens, a lens group, a fourth positive power lens and a third negative power lens arranged in sequence from the object side to the image side; the image side of the third negative power lens includes an image plane; the lens group satisfies the following conditions: #imgabs0# wherein f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens; the lens group is composed of a third positive focal length lens and a second negative focal length lens arranged in sequence from the object side to the image side. An optical lens with high resolution, miniaturization, low cost, and good temperature stability is realized.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging technology, and in particular to a lens and a camera device. Background Art

[0002] Thanks to the rapid development of the field of intelligent security in recent years, optical lenses have been increasingly used in the field of security, especially in the fields of intelligent buildings and intelligent transportation. The pixel requirements of optical imaging lenses are getting higher and higher. More and more companies are beginning to invest more in ultra-high definition research, hoping to develop products with higher pixels and smaller sizes. For optical lenses, the use of plastic lenses will greatly reduce the volume of products and reduce the price of products. More and more large-volume lenses are developing in the direction of a mixture of glass and plastic lenses. Moreover, the aspheric surface introduced by plastic lenses can greatly improve the imaging quality to a certain extent.

[0003] With the rapid development of the security field, the following problems still exist in current optical imaging lenses: 1. The existing fixed-focus optical lenses have small imaging target surfaces, most of which are concentrated at 1 / 2.7 inches and below. 2. Most optical lenses use 7, 8 or even more lenses. While improving the imaging quality, the size of the entire lens is also increased, and the miniaturization design requirements cannot be met. 3. Plastic lenses can greatly improve the consistency of mass production of products, and the use of plastic lenses will greatly reduce the cost of lenses. The glass-plastic hybrid lenses currently on the market are prone to poor temperature stability. 4. The existing fixed-focus lenses on the market generally have a small aperture, and the F number is F1.2 and above.

[0004] Therefore, there is an urgent need for an optical lens with high resolution, miniaturization, low cost, and good temperature stability. Summary of the invention

[0005] The embodiments of the present invention provide a lens and a camera device, which are used to provide an optical lens with high resolution, miniaturization, low cost, good temperature stability and other characteristics.

[0006] An embodiment of the present invention provides a lens, wherein the lens is composed of a first negative power lens, a first positive power lens, a second positive power lens, a lens group, a fourth positive power lens and a third negative power lens arranged in sequence from the object side to the image side; the image side of the third negative power lens includes an image plane;

[0007] The lens group meets the following conditions:

[0008]

[0009] Among them, f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens;

[0010] The lens group is composed of a third positive power lens and a second negative power lens which are arranged in sequence from the object side to the image side.

[0011] Furthermore, the first negative power lens is a meniscus lens, and a surface thereof facing the object side is a convex surface;

[0012] The first positive power lens is a meniscus lens, and a surface thereof facing the object side is a concave surface;

[0013] The second positive power lens is a meniscus lens, and the surface facing the object side is a convex surface;

[0014] The third positive power lens is a biconvex lens;

[0015] The second negative power lens is a biconcave lens;

[0016] The fourth positive power lens is a biconvex lens;

[0017] The third negative power lens is a meniscus lens, and a surface thereof facing the object side is a convex surface.

[0018] Further, the first negative power lens, the second positive power lens and the third negative power lens are aspherical lenses;

[0019] The first positive power lens, the third positive power lens, the second negative power lens and the fourth positive power lens are spherical lenses.

[0020] Furthermore, the central curvature radius R2 of the image side surface of the first negative power lens and the central curvature radius R3 of the object side surface of the first positive power lens satisfy:

[0021] Furthermore, the distance TTL from the object plane side of the first negative power lens to the image plane and the focal length f3 of the second positive power lens satisfy:

[0022] Furthermore, f4, the focal length of the third positive power lens, and f5, the focal length of the second negative power lens, satisfy: f4≤6.7; f5≥-5.6.

[0023] Furthermore, the Abbe number Vd1 of the first negative power lens, the Abbe number Vd6 of the fourth positive power lens, and the Abbe number Vd7 of the third negative power lens satisfy: Vd1≤55.8; Vd6≤48; Vd7≤55.8.

[0024] Furthermore, the refractive index Nd1 of the first negative power lens, the refractive index Nd6 of the fourth positive power lens, and the refractive index Nd7 of the third negative power lens satisfy: Nd1≤1.59; Nd6≤1.75; Nd7≤1.59.

[0025] Furthermore, an aperture stop is arranged between the second positive power lens and the third positive power lens.

[0026] On the other hand, an embodiment of the present invention provides a camera device, which includes: using any of the above-mentioned lenses to perform imaging.

[0027] The embodiment of the present invention provides a lens and an imaging device, wherein the lens is composed of a first negative power lens, a first positive power lens, a second positive power lens, a lens group, a fourth positive power lens and a third negative power lens arranged in sequence from the object side to the image side; the image side of the third negative power lens includes an image plane; and the lens group satisfies the following conditions: Among them, f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens; the lens group is composed of a third positive power lens and a second negative power lens arranged in sequence from the object side to the image side. In the embodiment of the present invention, 7 lenses with specific focal powers are arranged in sequence from the object side to the image side in a specific order in the lens, and the third positive power lens and the second negative power lens constitute a lens group, and the lens group satisfies: An optical lens with high resolution, miniaturization, low cost and good temperature stability is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of a lens structure provided by an embodiment of the present invention;

[0030] Figure 2 The optical transfer function (MTF) curve of the lens provided in Example 1 of the present invention at room temperature in the visible light band;

[0031] Figure 3 Field curvature and distortion diagram of the lens provided in Example 1 of the present invention in the visible light band;

[0032] Figure 4A transverse light fan diagram of the lens provided in Example 1 of the present invention in the visible light band;

[0033] Figure 5 A spot diagram of the lens provided in Example 1 of the present invention in the visible light band;

[0034] Figure 6 An optical transfer function (MTF) curve of the lens provided in Example 2 of the present invention at room temperature in the visible light band;

[0035] Figure 7 Field curvature and distortion diagram of the lens provided in Example 2 of the present invention in the visible light band;

[0036] Figure 8 A transverse light fan diagram of the lens provided in Example 2 of the present invention in the visible light band;

[0037] Fig. 9 This is a point diagram of the lens provided in Example 2 of the present invention in the visible light band. DETAILED DESCRIPTION

[0038] The present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Figure 1 A schematic diagram of a lens provided by an embodiment of the present invention, wherein the lens is composed of a first negative power lens L1, a first positive power lens L2, a second positive power lens L3, a lens group T1, a fourth positive power lens L6 and a third negative power lens L7 arranged in sequence from the object side to the image side; the image side of the third negative power lens L7 includes an image plane N;

[0040] The lens group meets the following conditions:

[0041]

[0042] Among them, f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens;

[0043] The lens group T1 is composed of a third positive power lens L4 and a second negative power lens L5 which are arranged in sequence from the object side to the image side.

[0044] An aperture stop P is provided between the second positive power lens L3 and the third positive power lens L4.

[0045] The aperture size of the aperture diaphragm determines the aperture value of the system and the depth of field during shooting. Its aperture size can be fixed, or an adjustable aperture diaphragm can be placed as needed to achieve adjustable light aperture, that is, to achieve the purpose of variable system aperture value and changing depth of field.

[0046] In the embodiment of the present invention, seven lenses with specific optical power are arranged in sequence from the object side to the image side in a specific order in the lens, and the third positive optical power lens and the second negative optical power lens constitute a lens group, and the lens group satisfies: An optical lens with high resolution, miniaturization, low cost and good temperature stability is realized.

[0047] In order to further improve the imaging quality of the lens, in an embodiment of the present invention, the first negative optical power lens is a meniscus lens, and the surface facing the object side is a convex surface;

[0048] The first positive power lens is a meniscus lens, and a surface thereof facing the object side is a concave surface;

[0049] The second positive power lens is a meniscus lens, and the surface facing the object side is a convex surface;

[0050] The third positive power lens is a biconvex lens;

[0051] The second negative power lens is a biconcave lens;

[0052] The fourth positive power lens is a biconvex lens;

[0053] The third negative power lens is a meniscus lens, and a surface thereof facing the object side is a convex surface.

[0054] In order to improve the processing performance of the lens, in the embodiment of the present invention, the first negative power lens, the second positive power lens and the third negative power lens are aspherical lenses;

[0055] The first positive power lens, the third positive power lens, the second negative power lens and the fourth positive power lens are spherical lenses.

[0056] In order to further improve the imaging quality of the lens and improve the processing performance of the lens, in an embodiment of the present invention, the central curvature radius R2 of the image side surface of the first negative optical power lens and the central curvature radius R3 of the object side surface of the first positive optical power lens satisfy the following relationship:

[0057] In order to further make the system compact, in an embodiment of the present invention, the distance TTL from the object plane side of the first negative power lens to the image plane and the focal length f3 of the second positive power lens satisfy:

[0058]

[0059] In order to further improve the imaging quality of the lens, in an embodiment of the present invention, the focal length f4 of the third positive power lens and the focal length f5 of the second negative power lens satisfy: f4≤6.7; f5≥-5.6.

[0060] In the embodiment of the present invention, in order to enable the lens to clearly image in a wide temperature range, in the embodiment of the present invention, the Abbe number Vd1 of the first negative focal lens, the Abbe number Vd6 of the fourth positive focal lens, and the Abbe number Vd7 of the third negative focal lens satisfy: Vd1≤55.8; Vd6≤48; Vd7≤55.8. In addition, satisfying: Vd1≤55.8; Vd6≤48; Vd7≤55.8 can also reduce the chromatic aberration of the image, thereby improving the imaging quality.

[0061] In order to improve the imaging quality of the lens and reduce the total length of the lens, in the embodiment of the present invention, the refractive index Nd1 of the first negative power lens, the refractive index Nd6 of the fourth positive power lens, and the refractive index Nd7 of the third negative power lens satisfy: Nd1≤1.59; Nd6≤1.75; Nd7≤1.59. In addition, satisfying: Nd1≤1.59; Nd6≤1.75; Nd7≤1.59 can also reduce spherical aberration and improve imaging quality.

[0062] On the other hand, an embodiment of the present invention provides a camera device, which includes: using the above-mentioned lens to perform imaging.

[0063] The optical performance achieved by the lens provided by the embodiment of the present invention is as follows:

[0064] The optical lens can support up to 1 / 1.8 inch imaging target surface, effectively achieving high resolution of the lens while ensuring imaging quality, and can be used in -30℃~80℃ environment. The imaging can support the use of sensors with a maximum target surface of 1 / 1.8 inch, and the total mechanical length of the lens does not exceed 22.5mm; the full field of view MTF value is above 0.6 at 100lp / mm; the aperture is large, and the F number is 1.0, which is particularly suitable for monitoring needs under low illumination conditions. It can meet the needs of different temperatures.

[0065] The following is an example of lens parameters provided by the embodiment of the present invention.

[0066] Embodiment 1:

[0067] In a specific implementation process, the curvature radius R, center thickness Tc, refractive index Nd, Abbe constant Vd and cone coefficient k of each lens of the lens meet the conditions listed in Table 1:

[0068]

[0069] Table 1

[0070] It should be noted that the mirror numbers in Table 1 are Figure 1 In the lens structure diagram shown, the surface numbers of the lenses from left to right.

[0071] Among them, the lens L1, the lens L3, and the lens L7 in the embodiment of the present invention are aspherical lenses.

[0072] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation:

[0073]

[0074] Among them, Z is the axial vector height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted sphere, which is the inverse of the radius of curvature; k is the fitting cone coefficient; AF is the coefficient of the 4th, 6th, 8th, 10th, 12th, and 14th order terms of the aspheric polynomial.

[0075]

[0076] Table 2

[0077] The lens provided in this embodiment has the following optical technical indicators:

[0078] Total optical length TTL≤22.5mm;

[0079] Lens focal length f: 8.2mm;

[0080] Lens field of view: 54.9°;

[0081] Optical distortion of the lens: 3.7%;

[0082] Lens aperture: FNO≤1.0;

[0083] Lens image size: φ8.8mm.

[0084] In Embodiment 1 of the present invention, lens L4 and lens L5 form lens group T1, and the focal length of lens group T1 is f T1 , the focal length of the lens system is f, the field of view of the lens system is FOV, satisfying The central curvature radius R2 of the image side of lens L1 of the optical lens and the central curvature radius R3 of the object side of lens L2 satisfy The focal length f3 of the lens L3 of the optical lens satisfies the total optical length TTL of the optical lens. The focal length of lens L4 of the optical lens is f4=6.67, and the focal length of lens L5 is f5=-5.44; the Abbe number Vd1=30.15 of the glass material of lens L1 of the optical lens, the Abbe number Vd6=47.92 of the glass material of lens L6, and the Abbe number Vd7=55.77 of the glass material of lens L7 of the optical lens; the refractive index Nd1=1.58 of the glass material of lens L1 of the optical lens, the refractive index Nd6=1.71 of the glass material of lens L6, and the refractive index Nd7=1.53 of the glass material of lens L7.

[0085] Embodiment 2:

[0086] In a specific implementation process, the curvature radius R, center thickness Tc, refractive index Nd, Abbe constant Vd and cone coefficient k of each lens of the lens meet the conditions listed in Table 3:

[0087]

[0088] Table 3

[0089] It should be noted that the mirror numbers in Table 3 are Figure 1 In the lens structure diagram shown, the surface numbers of the lenses from left to right.

[0090] Among them, the lens L1, the lens L3, and the lens L7 in the embodiment of the present invention are aspherical lenses.

[0091] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation:

[0092]

[0093] Among them, Z is the axial vector height of the aspheric surface in the Z direction; r is the height of the aspheric surface; c is the curvature of the fitted sphere, which is the inverse of the radius of curvature; k is the fitting cone coefficient; AF is the coefficient of the 4th, 6th, 8th, 10th, 12th, and 14th order terms of the aspheric polynomial.

[0094]

[0095] Table 4

[0096] The lens provided in this embodiment has the following optical technical indicators:

[0097] Total optical length TTL≤22.5mm;

[0098] Focal length of the lens: 8.9mm;

[0099] Field of view of the lens: 50.7°;

[0100] Optical distortion of the lens: 5.6%;

[0101] Lens aperture: FNO≤1.0;

[0102] Lens image size: φ8.8mm.

[0103] In Embodiment 2 of the present invention, lens L4 and lens L5 form lens group T1, and the focal length of lens group T1 is f T1 , the focal length of the lens system is f, the field of view of the lens system is FOV, satisfying The central curvature radius R2 of the image side surface of the lens L1 of the optical lens and the central curvature radius R3 of the object side surface of the lens L2 satisfy The focal length f3 of the lens L3 of the optical lens satisfies the total optical length TTL of the optical lens. The focal length of lens L4 of the optical lens is f4=6.20, and the focal length of lens L5 is f5=-5.20; the Abbe number Vd1=55.77 of the glass material of lens L1 of the optical lens, the Abbe number Vd6=35.02 of the glass material of lens L6, and the Abbe number Vd7=30.15 of the glass material of lens L7 of the optical lens; the refractive index Nd1=1.53 of the glass material of lens L1 of the optical lens, the refractive index Nd6=1.74 of the glass material of lens L6, and the refractive index Nd7=1.58 of the glass material of lens L7.

[0104] In summary, Example 1 and Example 2 respectively satisfy the relationship shown in the following Table 5.

[0105]

[0106] Table 5

[0107] The lens provided in this embodiment is further described below by analyzing the optical system of the embodiment in detail.

[0108] The optical transfer function is a relatively accurate, intuitive and common way to evaluate the imaging quality of an optical system. The higher and smoother the curve is, the better the imaging quality of the system is and the aberrations are well corrected.

[0109] like Figure 2 , which is a graph of the optical transfer function (MTF) of the lens provided in Example 1 at room temperature in the visible light band;

[0110] like Figure 3 As shown, it is a field curvature and distortion diagram of the lens provided in Example 1 in the visible light band;

[0111] like Figure 4 As shown, it is a transverse light fan diagram of the lens provided in Example 1 in the visible light band;

[0112] like Figure 5 As shown, it is a point diagram of the lens provided in Example 1 in the visible light band;

[0113] like Figure 6 , which is a graph of the optical transfer function (MTF) of the lens provided in Example 2 at room temperature in the visible light band;

[0114] like Figure 7 , which is a diagram of field curvature and distortion of the lens provided in Example 2 in the visible light band;

[0115] like Figure 8 As shown, it is a lateral light fan diagram of the lens provided in Example 2 in the visible light band;

[0116] like Fig. 9 As shown, it is a point diagram of the lens provided in Example 2 in the visible light band.

[0117] from Figure 2 It can be seen that the optical transfer function (MTF) curve of the lens in the visible light part at room temperature is smoother and more concentrated, and the average MTF value of the whole field of view (half image height Y'=4.4mm) is above 0.6; it can be seen that the lens provided in Example 1 of the present invention can meet higher imaging requirements.

[0118] from Figure 6 It can be seen that the optical transfer function (MTF) curve of the lens in the visible light part at room temperature is smoother and more concentrated, and the MTF average value of the whole field of view (half image height Y'=4.4mm) is above 0.6; it can be seen that the lens provided in Example 2 of the present invention can meet higher imaging requirements.

[0119] from Figure 3 and Figure 7 As can be seen from the figure, the field curvature of the lens is controlled within ±0.05mm. Figure 3 It can be seen that the field curvature of the fixed-focus lens provided in Example 1 of the present invention is within 0.02 mm. Figure 7It can be seen that the field curvature of the fixed-focus lens provided in Example 2 of the present invention is within 0.035mm. Field curvature is also called "field curvature". When the lens has field curvature, the intersection of the entire light beam does not coincide with the ideal image point. Although a clear image point can be obtained at each specific point, the entire image plane is a curved surface. T represents the meridian field curvature, and S represents the sagittal field curvature. The field curvature curve shows the distance from the current focal plane or image plane to the paraxial focal plane as a function of the field of view coordinates. The meridian field curvature data is the distance from the currently determined focal plane to the paraxial focal plane measured along the Z axis, and is measured on the meridian (YZ plane). The sagittal field curvature data measures the distance measured on a plane perpendicular to the meridian plane. The baseline in the schematic diagram is on the optical axis. The top of the curve represents the maximum field of view (angle or height). No unit is set on the vertical axis because the curve is always normalized with the maximum radial field of view.

[0120] from Figure 3 and Figure 7 It can be seen that the lens distortion is well controlled within 6%. Generally speaking, lens distortion is actually a general term for the inherent perspective distortion of optical lenses, that is, distortion caused by perspective. This distortion is very detrimental to the imaging quality of photos. After all, the purpose of photography is to reproduce, not exaggerate. However, because this is an inherent characteristic of the lens (convex lenses converge light, concave lenses diverge light), it cannot be eliminated, but can only be improved. Figure 3 It can be seen that the distortion of the fixed-focus lens provided in Example 1 of the present invention is only 3.8%, and the distortion of the fixed-focus lens provided in Example 2 of the present invention is only 5.6%. The distortion is set in this way to balance the focal length, the field of view angle and the size of the corresponding camera target surface. The deformation caused by the distortion can be corrected by post-image processing.

[0121] from Figure 4 and Figure 8 It can be seen that the curves in the light fan diagram are relatively concentrated, and the spherical aberration and dispersion of the lens are also well controlled. Figure 4 and Figure 8 In FIG. 1 , EX represents the aberration in the X direction, EY represents the aberration in the Y direction, PX represents the normalized pupil coordinate in the X direction, and PY represents the normalized pupil coordinate in the Y direction.

[0122] from Figure 5 and Fig. 9 It can be seen that the lens spot radius is small and concentrated, and the corresponding aberration and coma are also very good.

[0123] In summary, the embodiment of the present invention provides a low-cost, large target surface, large aperture, and high-definition imaging optical lens. Seven optical lenses with specific structural shapes are used, and are arranged in sequence from the object side to the image side in a specific order, and through the allocation and combination of the specific optical power of each optical lens, the lens can achieve better distortion control and excellent imaging characteristics.

[0124] The embodiment of the present invention provides a lens and an imaging device, wherein the lens is composed of a first negative power lens, a first positive power lens, a second positive power lens, a lens group, a fourth positive power lens and a third negative power lens arranged in sequence from the object side to the image side; the image side of the third negative power lens includes an image plane; and the lens group satisfies the following conditions: Among them, f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens; the lens group is composed of a third positive power lens and a second negative power lens arranged in sequence from the object side to the image side. In the embodiment of the present invention, 7 lenses with specific focal powers are arranged in sequence from the object side to the image side in a specific order in the lens, and the third positive power lens and the second negative power lens constitute a lens group, and the lens group satisfies: An optical lens with high resolution, miniaturization, low cost and good temperature stability is realized.

[0125] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0128] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0129] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A lens, characterized in that: The lens is composed of a first negative power lens, a first positive power lens, a second positive power lens, a lens group, a fourth positive power lens and a third negative power lens, which are arranged in sequence from the object side to the image side; the image side of the third negative power lens includes an image plane; The lens group meets the following conditions: Among them, f T1 is the focal length of the lens group, f is the focal length of the lens, and FOV is the field of view of the lens; The lens group is composed of a third positive power lens and a second negative power lens arranged in sequence from the object side to the image side; The central curvature radius R2 of the image side surface of the first negative power lens and the central curvature radius R3 of the object side surface of the first positive power lens satisfy:

2. The lens according to claim 1, wherein: The first negative power lens is a meniscus lens, and the surface facing the object side is a convex surface; The first positive power lens is a meniscus lens, and a surface thereof facing the object side is a concave surface; The second positive power lens is a meniscus lens, and a surface thereof facing the object side is a convex surface; The third positive power lens is a biconvex lens; The second negative power lens is a biconcave lens; The fourth positive power lens is a biconvex lens; The third negative power lens is a meniscus lens, and a surface thereof facing the object side is a convex surface.

3. The lens according to claim 1, wherein: The first negative power lens, the second positive power lens and the third negative power lens are aspherical lenses; The first positive power lens, the third positive power lens, the second negative power lens and the fourth positive power lens are spherical lenses.

4. The lens according to claim 1, wherein: The distance TTL from the object plane of the first negative power lens to the image plane and the focal length f3 of the second positive power lens satisfy:

5. The lens according to claim 1, wherein: The focal length f4 of the third positive power lens and the focal length f5 of the second negative power lens satisfy: f4≤6.7mm; f5≥-5.6mm.

6. The lens according to claim 1, wherein: The Abbe number Vd1 of the first negative power lens, the Abbe number Vd6 of the fourth positive power lens, and the Abbe number Vd7 of the third negative power lens satisfy the following: Vd1≤55.8; Vd6≤48; Vd7≤55.

8.

7. The lens according to claim 1, wherein: The refractive index Nd1 of the first negative power lens, the refractive index Nd6 of the fourth positive power lens, and the refractive index Nd7 of the third negative power lens satisfy: Nd1≤1.59; Nd6≤1.75; Nd7≤1.

59.

8. The lens according to claim 1, wherein: An aperture stop is arranged between the second positive power lens and the third positive power lens.

9. A camera device, characterized in that: The imaging device comprises the lens according to any one of claims 1 to 8.

Images