Optical lens

Abstract

The optical lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from an object plane to an image plane along an optical axis, the first lens has negative focal power, the second lens has negative focal power, the third lens has positive focal power, the fourth lens has positive focal power, the fifth lens has negative focal power, the sixth lens has positive focal power, and the seventh lens has negative focal power. The fifth lens has positive focal power, the sixth lens has negative focal power, and the seventh lens has positive focal power. According to the optical lens provided by the embodiment of the utility model, the seven lenses are adopted, and the focal power and the surface type of each lens are distributed, so that the total optical length of the lens is within 30mm, the aperture number is less than 1.65, the imaging requirement in a dark environment can be met, the imaging is clear, an imaging chip with more than 8 million pixels can be matched, and stable high and low temperature resolution can be ensured; the optical lens which is miniaturized, high in pixel and definition, large in aperture, high in relative illumination, large in field angle and weak in ghost image is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to optical technology field especially relates to an optical lens. BACKGROUND

[0002] With the development of automatic driving function, the vehicle-mounted lens as the key component of the automatic driving auxiliary system also has a rapid development, and the requirement for the lens is higher and higher. The vehicle-mounted optical lens is the key component for the automatic driving auxiliary system to obtain external information, and higher requirements are put forward for the performance and structure of the optical lens applied to the front view, for example, the front view optical lens is required to have high resolving power, large field of view, miniaturization, and at the same time, has large aperture, high relative luminance and high resolving power to meet the needs of automobile application.

[0003] However, most of the existing vehicle-mounted optical lenses are difficult to meet these requirements. For example, the existing vehicle-mounted optical lens cannot meet the requirements of high resolving power and miniaturization at the same time; although the existing vehicle-mounted optical lens can reach the clarity of one million pixels, the lens aberration problems such as chromatic aberration, astigmatism and distortion are relatively serious; the existing vehicle-mounted optical lens has weak light transmission capacity and cannot adapt to the relatively dark environment such as night or rainy day; the existing vehicle-mounted optical lens cannot meet the requirements of large aperture and high resolving power at the same time; the existing vehicle-mounted optical lens cannot meet the requirements of small aperture and weak ghost image at the same time, etc. CONTENT OF THE UTILITY MODEL

[0004] The utility model provides a kind of optical lens, to realize the optical lens of high pixel and high definition, large aperture, high relative luminance, large field of view and weak ghost image can be considered miniaturization.

[0005] The utility model provides a kind of optical lens, including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens and seventh lens sequentially arranged along optical axis from object plane to image plane;

[0006] The first lens has negative focal power, and its object side is convex, and the image side is concave;

[0007] The second lens has negative focal power, and its object side is concave, and the image side is concave;

[0008] The third lens has positive focal power, and its object side is convex, and the image side is convex;

[0009] The fourth lens has positive focal power, and its object side is convex, and the image side is convex;

[0010] The fifth lens has positive focal power, and its image side is convex, and the image side is convex;

[0011] The sixth lens has negative focal power, and its object side is concave, and the image side is convex;

[0012] The seventh lens has positive refractive power, and its object side surface is convex, and its image side surface is convex.

[0013] Optionally, a focal length of the optical lens is F, a focal length of the first lens is f1, a focal length of the second lens is f2, a focal length of the third lens is f3, a focal length of the fourth lens is f4, a focal length of the fifth lens is f5, a focal length of the sixth lens is f6, and a focal length of the seventh lens is f7.

[0014] -2 < f1 / F < 0; -3 < f2 / F < 0; 0 < f3 / F < 2; 0 < f4 / F < 3;

[0015] 0 < f5 / F < 2; -2 < f6 / F < 0; 0 < f7 / F < 3.5.

[0016] Optionally, a focal length of the optical lens is F, and an overall optical length of the optical lens is TTL.

[0017] TTL / F < 5.5.

[0018] Optionally, the fifth lens and the sixth lens form a cemented lens group.

[0019] Optionally, a focal length of the cemented lens group is f56, and a focal length of the optical lens is F.

[0020] 10 < |f56 / F| < 15.

[0021] Optionally, the optical lens further comprises a diaphragm.

[0022] The diaphragm is located in an optical path between the third lens and the fourth lens.

[0023] Optionally, an overall optical length of the optical lens is TTL, and an image height corresponding to a maximum field of view angle of the optical lens is H.

[0024] 6 < TTL / H < 7.

[0025] Optionally, an optical back focal length of the optical lens is BFL, and an overall optical length of the optical lens is TTL.

[0026] BFL / TTL > 1.0.

[0027] Optionally, an entrance pupil diameter of the optical lens is ENPD, and an overall optical length of the optical lens is TTL.

[0028] ENPD / TTL ≥ 0.1.

[0029] Optionally, a refractive index of the first lens is Nd1, and Nd1 ≥ 1.7.

[0030] Optionally, the focal length of the fifth lens is f5, and the focal length of the sixth lens is f6;

[0031] 0.5 < |f5 / f6| < 1.5.

[0032] Optionally, the focal length of the second lens is f2, and the focal length of the seventh lens is f7;

[0033] -1 < f2 / f7 < -0.7.

[0034] Optionally, the Abbe number of the fifth lens is Vd5, and the refractive index is Nd5;

[0035] the Abbe number of the sixth lens is Vd6, and the refractive index is Nd6;

[0036] 3 < Vd5 / Vd6 < 3.5; 0.8 < Nd5 / Nd6 < 0.9.

[0037] Optionally, the central curvature radius of the object side of the first lens is R1, the central curvature radius of the image side of the first lens is R2, and the central thickness of the first lens is d1;

[0038] 0.8 ≤ R1 / (R2+d1) ≤ 1.5.

[0039] Optionally, the central curvature radius of the object side of the second lens is R3, the central curvature radius of the image object side of the seventh lens is R13, and the focal length of the optical lens is F;

[0040] -5.5 < R3 / F < -4.5; 6 < R13 / F < 7.

[0041] Optionally, the central curvature radius of the object side of the first lens is R1, and the focal length of the optical lens is F;

[0042] 0.5 < R1 / F < 1.5.

[0043] The optical lens provided by the embodiment of the utility model, adopting seven lenses, by reasonably distributing the focal length and surface type of each lens, the optical total length of the lens is within 30mm, the aperture number is below 1.65, the imaging needs of darker environment can be met, the imaging is clear, the imaging chip above 8 million pixels can be matched, and stable high-low temperature resolution can be ensured, the optical lens with small size, high pixels, high definition, large aperture, high relative luminance, large field of view and weak ghost image can be considered.

[0044] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0046] Figure 1 A structural schematic diagram of an optical lens provided by the embodiment of the present application is shown in the figure.

[0047] Figure 2 A structural schematic diagram of another optical lens provided by the embodiment of the present application is shown in the figure.

[0048] Figure 3 A structural schematic diagram of another optical lens provided by the embodiment of the present application is shown in the figure.

[0049] Figure 4 A ray fan diagram of the optical lens provided by the first embodiment of the present application is shown in the figure.

[0050] Figure 5 An axial aberration curve diagram of the optical lens provided by the first embodiment of the present application is shown in the figure.

[0051] Figure 6 A field curvature distortion diagram of the optical lens provided by the first embodiment of the present application is shown in the figure.

[0052] Figure 7 A ray fan diagram of the optical lens provided by the second embodiment of the present application is shown in the figure.

[0053] Figure 8 An axial aberration curve diagram of the optical lens provided by the second embodiment of the present application is shown in the figure.

[0054] Figure 9 A field curvature distortion diagram of the optical lens provided by the second embodiment of the present application is shown in the figure.

[0055] Figure 10 A ray fan diagram of the optical lens provided by the third embodiment of the present application is shown in the figure.

[0056] Figure 11 An axial aberration curve diagram of the optical lens provided by the third embodiment of the present application is shown in the figure.

[0057] Figure 12The field curvature distortion chart of the optical lens is provided for the third embodiment of the utility model. DETAILED DESCRIPTION

[0058] In order to make the personnel in the technical field better understand the utility model scheme, the technical scheme in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the utility model.

[0059] It should be noted that the terms "first", "second" and the like in the description and claims of the utility model and the above drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the utility model described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to the clearly listed steps or units, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0060] Figure 1 The structural schematic diagram of the optical lens provided by the utility model embodiment, Figure 2 The structural schematic diagram of another optical lens provided by the utility model embodiment, Figure 3 The structural schematic diagram of another optical lens provided by the utility model embodiment, as Figures 1-3 As shown in the structural schematic diagram of the optical lens provided by the utility model embodiment, the optical lens comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence along an optical axis from an object plane to an image plane.

[0061] The first lens L1 has negative focal power, and the object side surface is a convex surface, and the image side surface is a concave surface.

[0062] The second lens L2 has negative focal power, and the object side surface is a concave surface, and the image side surface is a concave surface.

[0063] The third lens L3 has positive focal power, and the object side surface is a convex surface, and the image side surface is a convex surface.

[0064] The fourth lens L4 has positive focal power, and the object side surface is a convex surface, and the image side surface is a convex surface.

[0065] The fifth lens L5 has positive optical power, and its image-side surface is convex.

[0066] The sixth lens L6 has negative optical power, with its object side being concave and its image side being convex.

[0067] The seventh lens L7 has positive optical power, and its object side and image side are both convex.

[0068] Specifically, optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam; it characterizes the ability of an optical system to deflect light rays. The larger the absolute value of the optical power, the stronger the bending ability of light rays; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light rays is converging; when the optical power is negative, the refraction of light rays is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., one surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group).

[0069] In the lens provided in this embodiment, each lens can be fixed to a lens barrel. Figure 1 (Not shown in the text) but not limited to this.

[0070] The first lens L1 has negative optical power, which diverges light at the front of the optical lens, allowing more light to enter the subsequent lenses at a larger angle. This helps to expand the field of view of the optical lens, thereby capturing a wider scene and making it suitable for panoramic photography.

[0071] The second lens L2 has negative optical power, which can share the negative optical power at the front of the optical lens. This helps to avoid excessive light refraction caused by the excessive concentration of optical power in the first lens L1, and reduces the difficulty of chromatic aberration correction in the optical lens.

[0072] The third lens L3 has positive optical power, which is conducive to smooth light transition, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0073] The fourth lens L4 has positive optical power, which can reasonably distribute the optical power of the entire optical lens, which is beneficial to achieving temperature characteristics and ensuring that the lens can still maintain good image quality under high and low temperature conditions.

[0074] The fifth lens, L5, has positive optical power, which is beneficial for smooth light transition, facilitates the correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0075] The sixth lens L6 has negative optical power, which helps to increase the imaging area of ​​the optical lens, while balancing the various aberrations produced by the fifth lens L5 and improving the imaging quality of the optical lens.

[0076] The seventh lens L7 has positive focal power, helps to collect light, ensures light quantity, improves relative luminance, and makes the optical lens have improved luminance at the image plane.

[0077] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 adopt the focal power combination of negative-negative-positive-positive-positive-negative-positive, the focal power of each lens can be reasonably distributed, so that the light can be smoothly propagated in the optical lens, the light is prevented from being excessively bent on a lens surface, the imaging quality is improved, and an imaging chip with more than 8 million pixels can be matched.

[0078] Meanwhile, the surface shape of the lens affects the propagation direction of the light, determines how the light is bent when passing through the lens, and further affects the maximum aperture and light quantity of the lens, and the imaging quality and characteristics.

[0079] In the embodiment, the surface shapes of the lenses are further reasonably matched, the focal power requirements of the lenses are met, the required optical performance indexes (for example, miniaturization, high pixels, high definition, large aperture, high relative luminance, large field of view and weak ghost image) are achieved, the optical total length of the whole lens is further reduced, the miniaturized lens design is realized, the light path is smoother when passing through the whole lens, unnecessary reflection and absorption are reduced, and the imaging quality is improved.

[0080] The optical lens provided in the embodiment of the utility model, adopting seven lenses, reasonably distributing the focal power and surface shape of each lens, makes the optical total length of the lens be within 30mm (can reach below 27.5mm), the aperture number be below 1.65, can satisfy the imaging need of relatively dark environment, and the imaging is clear, can match the imaging chip with more than 8 million pixels, and can guarantee stable high and low temperature resolution, realizes the optical lens that can consider miniaturization, high pixels and high definition, large aperture, high relative luminance, large field of view and weak ghost image.

[0081] As a feasible implementation manner, the focal length of the optical lens is F, the focal length of the first lens L1 is f1, the focal length of the second lens L2 is f2, the focal length of the third lens L3 is f3, the focal length of the fourth lens L4 is f4, the focal length of the fifth lens L5 is f5, the focal length of the sixth lens L6 is f6, and the focal length of the seventh lens L7 is f7; -2 < f1 / F < 0; -3 < f2 / F < 0; 0 < f3 / F < 2; 0 < f4 / F < 3; 0 < f5 / F < 2; -2 < f6 / F < 0; and 0 < f7 / F < 3.5.

[0082] The first lens L1 has appropriate negative focal length, which is conducive to expanding the field of view of the optical lens.

[0083] The second lens L2 has a proper negative focal length, can share the negative optical power of the front end of the optical lens, thereby helping to avoid excessive deflection of light caused by too concentrated optical power of the first lens L1, and reducing the difficulty of chromatic aberration correction of the optical lens.

[0084] Meanwhile, by proper focal length distribution, the dependence on the precision of individual lenses can be reduced, the error accumulation in the assembly process can be alleviated, thereby reducing the negative impact caused by assembly tolerance and improving the production yield.

[0085] The third lens L3 has a proper positive focal length, helps to smoothly transition the light, facilitates correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0086] Further controlling the focal length of the fourth lens L4 can reasonably distribute the optical power of the entire optical lens, which is conducive to realizing temperature characteristics and ensuring that the lens can still guarantee good imaging quality under high and low temperature conditions.

[0087] The fifth lens L5 has a proper positive focal length, helps to smoothly transition the light, facilitates correction of astigmatism and field curvature, and improves the imaging quality of the optical lens.

[0088] The sixth lens L6 has a proper negative focal length, helps to increase the imaging area of the optical lens, balances various aberrations generated by the fifth lens L5, and improves the imaging quality of the optical lens.

[0089] The seventh lens L7, as the last lens, adopts a short focal length, helps to collect light, ensures the light quantity, improves the relative luminance, and improves the brightness at the image plane of the optical lens.

[0090] As a feasible implementation manner, the focal length of the optical lens is F, the total optical length of the optical lens is TTL, and TTL / F<5.5.

[0091] The total length TTL of the optical lens refers to the distance from the optical axis center of the object side surface of the first lens L1 to the image plane.

[0092] In the embodiment, by controlling the ratio between the total optical length TTL of the optical lens and the focal length F of the optical lens, the optical lens can be ensured to be as short as possible while maintaining a certain focal length, so that the lens is more compact and light, and miniaturization design is realized.

[0093] As a feasible implementation manner, as shown in Figures 1-3 the fifth lens L5 and the sixth lens L6 form a cemented lens group G.

[0094] The total length TTL of the optical lens refers to the distance from the optical axis center of the object side surface of the first lens L1 to the image plane. Figures 1-3As shown, the fifth lens L5 and the sixth lens L6 are cemented, which can effectively correct chromatic aberration of the optical lens, reduce the sensitivity of the optical lens to decentration, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; at the same time, the assembly sensitivity of the optical lens can be reduced, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0095] As a feasible implementation, the focal length of the cemented lens group G is f56, the focal length of the optical lens is F, and 10≤|f56 / F|≤15.

[0096] The absolute value of the ratio of the focal length f56 of the cemented lens group G to the focal length F of the optical lens is controlled in the range of 10 to 15, the light ray trend between the fourth lens L4 and the fifth lens L5 can be controlled, the aberration caused by the light ray with a large angle of incidence is reduced, the light ray is more smoothly transitioned to the subsequent lens, and thus the imaging quality is improved.

[0097] At the same time, controlling the range of f56 / F also helps to make the lens structure compact, so that the total length of the lens is shortened, which is beneficial to miniaturization design and can reduce the sensitivity.

[0098] As a feasible implementation, as shown, Figures 1-3 The optical lens further includes a stop STO, and the stop STO is located in the optical path between the third lens L3 and the fourth lens L4.

[0099] The stop STO is arranged between the third lens L3 and the fourth lens L4 to limit the light beam, and the stop STO can be arranged near the object side of the fourth lens L4, so that the generation of the astigmatism of the optical lens is reduced, and at the same time, the light ray entering the optical system is collected, and the rear aperture of the optical lens is reduced.

[0100] As a feasible implementation, the total optical length of the optical lens is TTL, the image height corresponding to the maximum field of view angle of the optical lens is H, and 6

[0101] By limiting the ratio between the total optical length TTL of the optical lens and the image height H corresponding to the maximum field of view angle of the optical lens, the total length of the lens can be better compressed while realizing a large image surface, so that the lens achieves the design goal of miniaturization, and the optical lens is convenient to be mounted on other imaging devices.

[0102] As a feasible implementation, the optical back focal length of the optical lens is BFL, the total optical length of the optical lens is TTL, and BFL / TTL>1.0.

[0103] The optical back focal length BFL of the optical lens refers to the distance from the optical axis center of the image side of the seventh lens L7 to the image surface.

[0104] In the embodiment, by reasonably limiting the ratio of the optical back focal length BFL and the total optical length TTL of the lens, on the basis of miniaturization, the longer back focal length can ensure that the imaging chip and the flat filter and other structures have sufficient installation space, so that the lens does not interfere with the base and the shell during installation, which is beneficial to the assembly of the module.

[0105] As a feasible implementation manner, the entrance pupil diameter of the optical lens is ENPD, the total optical length of the optical lens is TTL, and ENPD / TTL≥0.1.

[0106] Among them, by limiting the ratio between the entrance pupil diameter ENPD of the optical lens and the total optical length TTL of the optical lens, the lens can have a larger entrance pupil diameter, thereby realizing a small FNO (F-number), which is beneficial to realize a large aperture characteristic, provides more incident light for the optical lens, and is beneficial to improve the imaging quality under low light conditions.

[0107] As a feasible implementation manner, the refractive index of the first lens L1 is Nd1, and Nd1≥1.7.

[0108] Among them, the first lens L1 selects a high refractive index material, which is beneficial to make the front aperture smaller and improve the imaging quality.

[0109] As a feasible implementation manner, the focal length of the fifth lens L5 is f5, the focal length of the sixth lens L6 is f6, and 0.5<|f5 / f6|<1.5.

[0110] Among them, by setting the fifth lens L5 (positive focal power) and the sixth lens L6 (negative focal power) to be cemented, and having a reasonable focal length ratio, the effect of eliminating chromatic aberration can be achieved.

[0111] As a feasible implementation manner, the focal length of the second lens L2 is f2, the focal length of the seventh lens L7 is f7, and -1

[0112] Among them, by reasonably configuring the focal length ratio of the second lens L2 and the seventh lens L7, the aberrations formed by the second lens L2 and the seventh lens L7 can be mutually offset, thereby effectively improving the resolving power of the lens.

[0113] As a feasible implementation manner, the Abbe number of the fifth lens L5 is Vd5, and the refractive index is Nd5; the Abbe number of the sixth lens L6 is Vd6, and the refractive index is Nd6; 3

[0114] Among them, by increasing the Abbe number difference and the refractive index difference between the fifth lens L5 and the sixth lens L6, the elimination of chromatic aberration is more beneficial.

[0115] As a feasible implementation, the central curvature radius of the object side of the first lens L1 is R1, the central curvature radius of the image side of the first lens L1 is R2, and the central thickness of the first lens L1 is d1, and 0.8≤R1 / (R2+d1)≤1.5.

[0116] Wherein, by setting the special lens shape of the first lens L1 (the shape of the first lens L1 is close to a concentric circle), the optical path difference between the peripheral light and the central light is caused, which is helpful to disperse the central light and make it enter the rear optical system more uniformly, and reduce the front aperture of the lens, reduce the volume, and is beneficial to miniaturization and cost reduction.

[0117] As a feasible implementation, the central curvature radius of the object side of the second lens L2 is R3, the central curvature radius of the image object side of the seventh lens L7 is R13, and the focal length of the optical lens is F, and -5.5

[0118] Wherein, by controlling the curvature radii of the second lens L2 and the seventh lens L7, the relative positions of the pupil images of the second lens L2 and the seventh lens L7 on the focal plane can be changed, so that the pupil images of the ghost images are far away from the focal plane, effectively reducing the relative energy value of the ghost images, and meeting the requirement of weak ghost images.

[0119] As a feasible implementation, the central curvature radius of the object side of the first lens L1 is R1, and the focal length of the optical lens is F, and 0.5

[0120] Wherein, by controlling the lower limit of R1 / F, the field of view of the optical lens can be increased, thereby meeting the requirement of wide-range shooting; at the same time, by controlling the upper limit of R1 / F, the effective aperture of the lens can be reduced, thereby realizing miniaturization design.

[0121] As a feasible implementation, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all glass lenses.

[0122] Wherein, compared with plastic lenses, the refractive index of glass lenses changes less with temperature, and setting each lens as a glass lens can help to maintain the stability of the focal length of each lens at different temperatures, so that the lens is not sensitive to high and low temperatures, and the influence of high and low temperatures on the entire lens can be well balanced., will not produce obvious aberration or other optical problems due to temperature change, so that the optical lens can clearly image in the temperature range of-40℃ to +85℃, and is particularly suitable for the field of video shooting in harsh environments such as motion cameras and vehicle-mounted cameras.

[0123] As a feasible implementation, the first lens L1 is an aspherical lens, and the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are spherical lenses.

[0124] The first lens L1 is an aspherical lens, which is beneficial to reduce the effective aperture of the front end of the optical lens, and make the whole lens more compact and light.

[0125] Meanwhile, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are spherical lenses, which is helpful to reduce the cost and easy to manufacture.

[0126] As a feasible implementation, as shown in Figures 1-3 The optical lens further comprises a flat filter CG, and the flat filter CG is located on the image side of the seventh lens L7, which can protect the imaging chip, prevent dust and pollution, and further ensure the imaging effect of the lens.

[0127] In some cases, the flat filter CG can also be used to correct specific aberrations or filter unnecessary light, and the embodiments of the utility model do not make specific limitations.

[0128] The specific embodiments of the optical lens applicable to the above embodiments will be further described below with reference to the drawings.

[0129] Embodiment one

[0130] Continuing to refer to Figure 1 The optical lens provided by the embodiment one of the utility model comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence along an optical axis from an object plane to an image plane.

[0131] The fifth lens L5 and the sixth lens L6 form a cemented lens group G; a stop STO is located in the optical path between the third lens L3 and the fourth lens L4; and a flat filter CG is located on the image side of the seventh lens L7.

[0132] Table 1 details the surface type, curvature radius, thickness, refractive index and Abbe number of each lens in the optical lens provided by the embodiment one in a feasible implementation, and the optical lens in Table 1 corresponds to Figure 1 The optical lens shown in the figure.

[0133] Table 1 Design values of optical physical parameters of the optical lens

[0134]

[0135]

[0136] In Table 1, the surface number is numbered according to the surface sequence of each lens, wherein "1" represents the object side surface of the first lens, "2" represents the image side surface of the first lens, and the like; the radius of curvature represents the bending degree of the lens surface, and the unit is millimeter (mm), a positive value represents that the surface is bent to the image side, and a negative value represents that the surface is bent to the object side, wherein "PL" represents that the surface is a plane, and the radius of curvature is infinite; the thickness represents the center axial distance from the current surface to the next surface, and the unit is millimeter (mm); the material (nd) represents the refractive index, which is the deflection ability of the material between the current surface and the next surface to light; and the space represents that the current position is air, and the refractive index is 1; the material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface to light.

[0137] In this embodiment, the first lens is an aspherical lens, and the object side surface 1 and the image side surface 2 are both aspherical surfaces.

[0138] The aspherical surface shape equation Z can satisfy:

[0139]

[0140] In the formula, Z is the distance vector height of the aspherical surface at a position with a height of y along the optical axis direction from the vertex of the aspherical surface; c=1 / R, R represents the paraxial curvature radius of the mirror; K is the conic coefficient; A, B, C, D, and E are high-order aspherical coefficients.

[0141] For example, Table 2 details the conic coefficient K and the high-order coefficients A, B, C, D, and E of the aspherical lens surfaces 1 and 2 in Embodiment I in a feasible implementation manner.

[0142] Table 2: Design values of aspherical conic coefficients of the aspherical lens in the optical lens

[0143] Serial number K A B C D E 1 -1.06 -8.2E-04 -8.5E-05 2.9E-06 -3.2E-08 4.4E-11 2 -0.64 -2.0E-03 -5.7E-04 6.2E-05 -5.6E-06 2.0E-07

[0144] The optical total length of the optical lens provided in Embodiment I is 27.17372 mm.

[0145] Figure 4 The ray fan diagram of the optical lens provided in Embodiment I of the utility model can not only reflect the monochromatic aberration of different wavelengths, but also represent the size of the sagittal chromatic aberration. In the diagram, the ray fan diagram of the optical lens at an infinite object distance is shown, the horizontal coordinate in a single diagram is the normalized beam aperture, the vertical coordinate is the sagittal aberration, and the vertical coordinate in a single image can also represent the maximum dispersion range of the light beam on the ideal image plane. In an ideal case, each curve should be completely coincident with the horizontal coordinate axis, at which time all the light beams in the field of view are focused on the same point on the image plane. According to the diagram, the size of the sagittal chromatic aberration can be determined.Figure 4 It can be seen that the optical lens has better correction on the sagittal aberration of each wavelength, and the curves of each color are not obviously dispersed, which indicates that the optical lens has better correction on chromatic aberration and can meet the use requirement of the optical lens.

[0146] Figure 5 The axial aberration curve of the optical lens is provided in the embodiment one of the utility model, wherein, the axial aberration curve of the lens can better show the spherical aberration and other parameter states of the optical system under different wavelength conditions, the vertical direction in the figure indicates the normalization of the aperture, 0 indicates on the optical axis, and the top indicates the maximum pupil radius; the horizontal direction indicates the offset from the ideal focus, and the unit is millimeter (mm). From the above, Figure 5 It can be seen that the axial aberration of the normalized aperture of different wavelengths is within a reasonable range, and the effect of clear image can be realized.

[0147] Figure 6 The field curvature distortion graph of the optical lens is provided in the embodiment one of the utility model, in the left coordinate system in the figure, the horizontal coordinate indicates the size of the field curvature, and the unit is mm; the vertical coordinate indicates the normalized image height without unit, wherein, T indicates meridian, and S indicates arc loss. In the right coordinate system in the figure, the horizontal coordinate indicates the size of the distortion (F-Tan(Theta)), and the unit is %; the vertical coordinate indicates the normalized image height without unit. From the above, Figure 6 It can be seen that the field curvature of the optical lens provided in the embodiment is effectively controlled, and the distortion is also better corrected.

[0148] Embodiment two

[0149] Continuously referring to Figure 2 The optical lens provided in the embodiment two of the utility model comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence along an optical axis from an object plane to an image plane.

[0150] The fifth lens L5 and the sixth lens L6 form a cemented lens group G; a stop STO is located in the optical path between the third lens L3 and the fourth lens L4; and a flat filter CG is located on one side of the image side of the seventh lens L7.

[0151] Table 3 details the surface type, curvature radius, thickness, refractive index and Abbe number of each lens in the optical lens provided in the embodiment two in a feasible implementation manner, and the optical lens in table 3 corresponds to the optical lens shown in the figure. Figure 2

[0152] Table 3 design values of optical physical parameters of the optical lens

[0153] Surface number Surface type Radius of curvature Thickness Material (nd) Material (vd) 1 Asphere 5.00 1.95 1.806 40.91 2 Asphere 2.48 2.70 3 Sphere -25.00 0.70 1.487 70.44 4 Sphere 8.30 1.90 5 Sphere 24.31 2.20 1.871 40.73 6 Sphere -11.75 3.01 STO (stop) PL Infinity 0.25 8 Sphere 50.00 1.90 1.593 68.34 9 Sphere -8.75 0.10 10 Sphere 40.00 2.80 1.497 81.61 11 Sphere -5.26 0.60 1.847 23.78 12 Sphere -21.91 0.10 13 Sphere 34.00 2.20 1.743 49.22 14 Sphere -15.94 2.00 15 Sphere Infinity 0.30 1.517 64.20 16 Sphere Infinity 3.89 17 Sphere Infinity 0.50 1.517 64.20 18 Sphere Infinity 0.05 IMA Infinity / ​

[0154] In Table 3, the surface number is numbered according to the surface sequence of each lens, wherein "1" represents the object side surface of the first lens, "2" represents the image side surface of the first lens, and the like; the radius of curvature represents the bending degree of the lens surface, and the unit is millimeter (mm), a positive value represents that the surface is bent to the image side, and a negative value represents that the surface is bent to the object side, wherein "PL" represents that the surface is a plane, and the radius of curvature is infinite; the thickness represents the center axial distance from the current surface to the next surface, and the unit is millimeter (mm); the material (nd) represents the refractive index, which is the deflection ability of the material between the current surface and the next surface to light; and the space represents that the current position is air, and the refractive index is 1; the material (vd) represents the Abbe number, which is the dispersion characteristic of the material between the current surface and the next surface to light.

[0155] In this embodiment, the first lens is an aspherical lens, and the object side surface 1 and the image side surface 2 are both aspherical surfaces.

[0156] The aspherical surface shape equation Z can satisfy:

[0157]

[0158] In the formula, Z is the distance vector height of the aspherical surface at a position with a height of y along the optical axis direction from the vertex of the aspherical surface; c = 1 / R, R represents the paraxial curvature radius of the mirror; K is the conic coefficient; A, B, C, D and E are high-order aspherical coefficients.

[0159] For example, Table 4 details the conic coefficient K and the high-order coefficients A, B, C, D and E of the aspherical lens surface 1 and surface 2 in this embodiment two in a feasible implementation manner.

[0160] Table 4: Design values of aspherical conic coefficients of the aspherical lens in the optical lens

[0161] Serial number K A B C D E 1 -1.06 -9.1E-04 -9.7E-05 3.7E-06 -5.4E-08 2.8E-10 2 -0.65 -2.0E-03 -7.0E-04 9.3E-05 -1.0E-05 6.3E-07

[0162] The optical total length of the optical lens provided in this embodiment two is 27.14996 mm.

[0163] Figure 7 The ray fan diagram of the optical lens provided in this embodiment two can not only reflect the monochromatic aberration of different wavelengths, but also represent the size of the sagittal chromatic aberration. In the diagram, the ray fan diagram of the optical lens at an infinite object distance is shown, the horizontal coordinate in a single diagram is a normalized beam aperture, the vertical coordinate is a sagittal aberration, and the vertical coordinate in a single image can also represent the maximum dispersion range of the light beam on the ideal image plane. In an ideal case, each curve should be completely coincident with the horizontal coordinate axis, at which time all the light rays in the field of view are focused on the same point on the image plane. From the diagram, it can be seen that the ray fan diagram of the optical lens provided in this embodiment two is relatively symmetrical, and the astigmatism is small, which indicates that the optical lens has good imaging performance. Figure 7It can be seen that the optical lens has better correction on the sagittal aberration of each wavelength, and the curves of each color are not obviously dispersed, which indicates that the optical lens has better correction on chromatic aberration and can meet the use requirement of the optical lens.

[0164] Figure 8 The axial aberration curve of the optical lens is provided in the second embodiment of the utility model, wherein the axial aberration curve of the lens can better show the spherical aberration and other parameter states of the optical system under different wavelength conditions, the vertical direction in the figure represents the normalization of the aperture, 0 represents on the optical axis, and the top point represents the maximum pupil radius; the horizontal direction represents the offset from the ideal focus point, and the unit is millimeter (mm). Figure 8 It can be seen that the axial aberration of the normalized aperture of different wavelengths is within a reasonable range, and the effect of clear image can be realized.

[0165] Figure 9 The field curvature distortion graph of the optical lens is provided in the second embodiment of the utility model, in the left coordinate system in the figure, the horizontal coordinate represents the size of the field curvature, and the unit is mm; the vertical coordinate represents the normalized image height, and has no unit, wherein T represents meridian, and S represents arc loss. In the right coordinate system in the figure, the horizontal coordinate represents the size of the distortion (F-Tan (Theta)), and the unit is %; the vertical coordinate represents the normalized image height, and has no unit. Figure 9 It can be seen that the field curvature of the optical lens provided in the embodiment is effectively controlled, and the distortion is also better corrected.

[0166] Embodiment three

[0167] Continuously referring to Figure 3 The optical lens provided in the third embodiment of the utility model comprises a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence along an optical axis from an object plane to an image plane.

[0168] The fifth lens L5 and the sixth lens L6 form a cemented lens group G; a stop STO is located in the optical path between the third lens L3 and the fourth lens L4; and a flat filter CG is located on one side of the image side of the seventh lens L7.

[0169] Table 5 details the surface type, curvature radius, thickness, refractive index and Abbe number of each lens in the optical lens provided in the third embodiment in a feasible implementation manner, and the optical lens in Table 5 corresponds to Figure 3 the optical lens shown in the figure.

[0170] Table 5 design values of optical physical parameters of the optical lens

[0171] Surface number Surface type Radius of curvature Thickness Material (nd) Material (vd) 1 Asphere 5.50 2.30 1.806 40.91 2 Asphere 2.50 2.70 3 Sphere -25.00 0.70 1.487 70.44 4 Sphere 8.30 1.90 5 Sphere 16.11 2.20 1.871 40.73 6 Sphere -12.65 2.60 STO (stop) PL Infinity 0.25 8 Sphere 50.00 1.90 1.593 68.34 9 Sphere -8.75 0.10 10 Sphere 40.00 2.44 1.497 81.61 11 Sphere -4.80 0.60 1.847 23.78 12 Sphere -19.51 0.10 13 Sphere 33.50 3.50 1.743 49.22 14 Sphere -15.79 2.00 15 Sphere Infinity 0.30 1.517 64.20 16 Sphere Infinity 3.17 17 Sphere Infinity 0.50 1.517 64.20 18 Sphere Infinity 0.05 IMA Infinity /

[0172] In the table 5, the surface sequence number is numbered according to the surface sequence of each lens, wherein "1" represents the object side surface of the first lens, "2" represents the image side surface of the first lens, and the like; the radius of curvature represents the bending degree of the lens surface, and the unit is millimeter (mm), wherein the positive value represents that the surface is bent to the image side, and the negative value represents that the surface is bent to the object side, wherein "PL" represents that the surface is a plane, and the radius of curvature is infinite; the thickness represents the center axial distance from the current surface to the next surface, and the unit is millimeter (mm); the material (nd) represents the refractive index, which refers to the deflection ability of the material between the current surface and the next surface to the light; and the space represents that the current position is air, and the refractive index is 1; the material (vd) represents the Abbe number, which refers to the dispersion characteristic of the material between the current surface and the next surface to the light.

[0173] In this embodiment, the first lens is an aspherical lens, and the object side surface 1 and the image side surface 2 are both aspherical surfaces.

[0174] The aspherical surface shape equation Z can meet the following formula:

[0175]

[0176] In the formula, Z is the distance vector height of the aspherical surface at a position with a height of y along the optical axis direction from the vertex of the aspherical surface; c = 1 / R, R represents the paraxial curvature radius of the lens; K is the conic coefficient; A, B, C, D and E are high-order aspherical coefficients.

[0177] For example, the table 6 details the conic coefficient K and the high-order coefficients A, B, C, D and E of the aspherical lens surface 1 and surface 2 in this embodiment three in a feasible implementation manner.

[0178] Table 6: Design values of aspherical conic coefficients of the aspherical lens in the optical lens

[0179] Serial number K A B C D E 1 -1.01 -8.4E-04 -6.2E-05 1.8E-06 -9.1E-09 -1.3E-10 2 -0.58 -2.6E-03 -4.5E-04 3.1E-05 -9.0E-07 -4.0E-07

[0180] The optical total length of the optical lens provided in this embodiment three is 27.30174 mm.

[0181] Figure 10 The ray fan diagram of the optical lens provided in this embodiment three, the ray fan diagram can not only reflect the monochromatic aberration of different wavelengths, but also can represent the size of the sagittal chromatic aberration. In the diagram, the ray fan diagram of the optical lens at the infinite object distance is shown, the horizontal coordinate in a single diagram is the normalized beam aperture, the vertical coordinate is the sagittal aberration, and the vertical coordinate in a single image can also be represented as the maximum dispersion range of the light beam on the ideal image plane. In an ideal case, each curve should be completely coincident with the horizontal coordinate axis, at this time, all the light rays in the field of view are focused on the same point on the image plane. From the diagram, it can be seen that the ray fan diagram of the optical lens provided in this embodiment three is relatively good, and the ray fan diagram is relatively small, which indicates that the optical lens provided in this embodiment three has good imaging performance. Figure 10It can be seen that the optical lens has good correction on the sagittal aberration of each wavelength, and the curves of each color are not obviously dispersed, which indicates that the optical lens has good correction on chromatic aberration and can meet the use requirement of the optical lens.

[0182] Figure 11 The axial aberration curve diagram of the optical lens is provided for the third embodiment of the utility model, wherein the axial aberration curve of the lens can preferably show the spherical aberration and other parameter states of the optical system under different wavelength conditions, the vertical direction in the diagram represents the normalization of the aperture, 0 represents on the optical axis, and the top point represents the maximum pupil radius; the horizontal direction represents the offset from the ideal focus point, and the unit is millimeter (mm). Figure 11 It can be seen that the axial aberration of the normalized aperture of different wavelengths is within a reasonable range, and the effect of a clear image can be achieved.

[0183] Figure 12 The field curvature distortion diagram of the optical lens is provided for the third embodiment of the utility model, in the left coordinate system in the diagram, the horizontal coordinate represents the size of the field curvature, and the unit is mm; the vertical coordinate represents the normalized image height without unit, wherein T represents meridian, and S represents arc loss. Figure 12 It can be seen that the field curvature of the optical lens provided in the embodiment is effectively controlled, and the distortion is also well corrected.

[0184] In order to more clearly illustrate the above embodiments, Table 7 details the specific optical physical parameters of each lens in the optical lens provided by the first to third embodiments of the utility model.

[0185] Table 7: Design values of optical physical parameters of the optical lens

[0186] Example one Example two Example three TTL / H 6.740 6.734 6.771 TTL / F 5.345 5.334 5.369 BFL / TTL 1.341 1.324 1.184 ENPD / TTL 0.113 0.115 0.114 f1 / F -1.809 -1.827 -1.696 f2 / F -2.534 -2.486 -2.488 f3 / F 1.802 1.829 1.650 f4 / F 2.583 2.490 2.493 f5 / F 1.839 1.870 1.724 f6 / F -1.493 -1.550 -1.382 |f5 / f6| 1.232 1.206 1.247 f7 / F 2.815 2.909 2.914 f2 / f7 -0.900 -0.854 -0.854 |f56 / F| 12.688 13.099 11.954 Vd5 / Vd6 3.431 3.431 3.431 Nd5 / Nd6 0.811 0.811 0.811 R1 / (R2+d1) 1.130 1.128 1.145 R3 / F -4.918 -4.911 -4.917 R13 / F 6.491 6.680 6.588 R1 / F 0.997 0.982 1.082

[0187] The above specific embodiments do not constitute a limitation on the protection scope of the utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. An optical lens characterized in that, The optical lens comprises, in sequence from the object plane to the image plane along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens; The first lens has negative focal power, the object side surface is a convex surface, and the image side surface is a concave surface; The second lens has negative focal power, the object side surface is a concave surface, and the image side surface is a concave surface; The third lens has positive focal power, the object side surface is a convex surface, and the image side surface is a convex surface; The fourth lens has positive focal power, the object side surface is a convex surface, and the image side surface is a convex surface; The fifth lens has positive focal power, the image side surface is a convex surface, and the image side surface is a convex surface; The sixth lens has negative focal power, the object side surface is a concave surface, and the image side surface is a convex surface; The seventh lens has positive focal power, the object side surface is a convex surface, and the image side surface is a convex surface.

2. The optical lens according to claim 1, wherein a focal length of the optical lens is F, a focal length of the first lens is f1, a focal length of the second lens is f2, a focal length of the third lens is f3, a focal length of the fourth lens is f4, a focal length of the fifth lens is f5, a focal length of the sixth lens is f6, and a focal length of the seventh lens is f7; -2 < f1 / F < 0; -3 < f2 / F < 0; 0 < f3 / F < 2; 0 < f4 / F < 3; 0 < f5 / F < 2; -2 < f6 / F < 0; and 0 < f7 / F < 3.

5.

3. The optical lens according to claim 1, wherein a focal length of the optical lens is F, and an overall optical length of the optical lens is TTL; TTL / F < 5.

5.

4. The optical lens according to claim 1, wherein the fifth lens and the sixth lens form a cemented lens group.

5. The optical lens according to claim 4, wherein a focal length of the cemented lens group is f56, and a focal length of the optical lens is F; 10 < |f56 / F| < 15.

6. The optical lens according to claim 1, wherein the optical lens further comprises a diaphragm; and the diaphragm is located in an optical path between the third lens and the fourth lens.

7. The optical lens according to claim 1, wherein an overall optical length of the optical lens is TTL, and an image height corresponding to a maximum field of view angle of the optical lens is H; 6 < TTL / H < 7.

8. The optical lens according to claim 1, wherein an optical back focal length of the optical lens is BFL, and an overall optical length of the optical lens is TTL; BFL / TTL > 1.

0.

9. The optical lens according to claim 1, wherein an entrance pupil diameter of the optical lens is ENPD, and an overall optical length of the optical lens is TTL; ENPD / TTL ≥ 0.

1.

10. The optical lens according to claim 1, wherein a refractive index of the first lens is Nd1, and Nd1 ≥ 1.

7.

11. The optical lens according to claim 1, wherein a focal length of the fifth lens is f5, and a focal length of the sixth lens is f6; 0.5 < |f5 / f6| < 1.

5. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 12. The optical lens according to claim 1, wherein, a focal length of the second lens is f2, and a focal length of the seventh lens is f7; -1 < f2 / f7 < -0.

7.

13. The optical lens according to claim 1, wherein, an Abbe number of the fifth lens is Vd5, and a refractive index of the fifth lens is Nd5; an Abbe number of the sixth lens is Vd6, and a refractive index of the sixth lens is Nd6; 3 < Vd5 / Vd6 < 3.5; 0.8 < Nd5 / Nd6 < 0.

9.

14. The optical lens according to claim 1, wherein, a central curvature radius of an object side surface of the first lens is R1, a central curvature radius of an image side surface of the first lens is R2, and a central thickness of the first lens is d1; 0.8 < R1 / (R2+d1) < 1.

5.

15. The optical lens according to claim 1, wherein, a central curvature radius of an object side surface of the second lens is R3, a central curvature radius of an image side surface of the seventh lens is R13, and a focal length of the optical lens is F; -5.5 < R3 / F < -4.5; 6 < R13 / F < 7.

16. The optical lens according to claim 1, wherein, a central curvature radius of an object side surface of the first lens is R1, and a focal length of the optical lens is F; 0.5 < R1 / F < 1.5.

Images