Optical lens

Abstract

The application provides an optical lens, which comprises six lenses in sequence along an optical axis from an object side to an imaging surface, and the six lenses comprise: a first lens with negative optical power, wherein the object side surface of the first lens is a concave surface, and the image side surface of the first lens is a convex surface; a second lens with positive optical power; a third lens with positive optical power, wherein the object side surface of the third lens is a convex surface; a fourth lens with negative optical power, wherein the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein the object side surface of the fifth lens is a convex surface; and a sixth lens with negative optical power, wherein the image side surface of the sixth lens is a concave surface. The optical lens provided by the application adopts six lenses with specific optical power, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as a large target surface, a large aperture, high imaging quality and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] With the continuous improvement of people's requirements for driving experience, vehicle application type optical lenses are increasingly used in intelligent driving, and vehicle optical lenses are continuously improving in the automotive industry.

[0003] Advanced Driver Assistance System (ADAS) plays an important role in intelligent driving, which collects environmental information through various lenses and sensors to ensure the safety of drivers. In addition to the requirements of optical lenses for the existing ADAS system, such as light and thin shape, high pixel, high resolution and other characteristics, the optical lens is also required to clearly image under low illumination conditions, so it is necessary to develop an optical lens with good imaging effect. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide an optical lens with the advantages of excellent imaging quality.

[0005] The technical scheme adopted by the present application is:

[0006] An optical lens, a total of six lenses, including in order along the optical axis from the object side to the imaging surface:

[0007] The first lens has negative focal power, the object side surface is concave, and the image side surface is convex;

[0008] The second lens has positive focal power;

[0009] The third lens has positive focal power, and the object side surface is convex;

[0010] The fourth lens has negative focal power, the object side surface is concave, and the image side surface is convex;

[0011] The fifth lens has positive focal power, and the object side surface is convex;

[0012] The sixth lens has negative focal power, and the image side surface is concave.

[0013] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5 < TTL / f < 2.3.

[0014] Further preferably, the real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 0.55 < IH / f < 0.7.

[0015] It is further preferred that the optical total track length TTL of the optical lens, the maximum field of view FOV of the optical lens and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 45 < 180° x TTL / (IH / 2) / (FOV / 2) < 80.

[0016] It is further preferred that the object side light aperture D1 of the first lens, the real image height IH corresponding to the maximum field of view FOV of the optical lens and the maximum field of view FOV of the optical lens satisfy: 3 < D1 / IH / Tan(FOV / 2) < 4.

[0017] It is further preferred that the effective focal length f of the optical lens and the object side curvature radius R5 of the third lens satisfy: 0.6 < R5 / f < 1.2.

[0018] It is further preferred that the effective focal length f of the optical lens and the object side curvature radius R9 of the fifth lens satisfy: 0.4 < R9 / f < 1.1.

[0019] It is further preferred that the effective focal length f of the optical lens and the image side curvature radius R12 of the sixth lens satisfy: 0.3 < R12 / f < 0.6.

[0020] It is further preferred that the object side curvature radius R1 of the first lens and the image side curvature radius R2 of the first lens satisfy: -0.6 < (R1-R2) / (R1+R2) < -0.2.

[0021] It is further preferred that the object side curvature radius R7 of the fourth lens and the image side curvature radius R8 of the fourth lens satisfy: -0.9 < (R7-R8) / (R7+R8) < -0.6.

[0022] The optical lens provided by the application adopts six lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages of large target surface, large aperture, high imaging quality and the like. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which:

[0024] Figure 1 FIG. 1 is a structure diagram of an optical lens according to an embodiment of the present application.

[0025] Figure 2 FIG. 2 is a field curvature curve diagram of the optical lens according to the embodiment of the present application.

[0026] Figure 3 F-Tan(Theta) Distortion curve of the optical lens in Embodiment 1 of the present application.

[0027] Figure 4 MTF curve of the optical lens in Embodiment 1 of the present application.

[0028] Figure 5 Structure diagram of the optical lens in Embodiment 2 of the present application.

[0029] Figure 6 Curvature of field curve of the optical lens in Embodiment 2 of the present application.

[0030] Figure 7 F-Tan(Theta) Distortion curve of the optical lens in Embodiment 2 of the present application.

[0031] Figure 8 MTF curve of the optical lens in Embodiment 2 of the present application.

[0032] Figure 9 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0033] Figure 10 Curvature of field curve of the optical lens in Embodiment 3 of the present application.

[0034] Figure 11 F-Tan(Theta) Distortion curve of the optical lens in Embodiment 3 of the present application.

[0035] Figure 12 MTF curve of the optical lens in Embodiment 3 of the present application.

[0036] Figure 13 Structure diagram of the optical lens in Embodiment 4 of the present application.

[0037] Figure 14 Curvature of field curve of the optical lens in Embodiment 4 of the present application.

[0038] Figure 15 F-Tan(Theta) Distortion curve of the optical lens in Embodiment 4 of the present application.

[0039] Figure 16 MTF curve of the optical lens in Embodiment 4 of the present application.

[0040] Figure 17 Structure diagram of the optical lens in Embodiment 5 of the present application.

[0041] Figure 18 Curvature of field curve of the optical lens in Embodiment 5 of the present application.

[0042] Figure 19F-Tan(Theta) distortion curve of the optical lens in Embodiment 5 of the present application.

[0043] Figure 20 MTF curve of the optical lens in Embodiment 5 of the present application.

[0044] Figure 21 Structure diagram of the optical lens in Embodiment 6 of the present application.

[0045] Figure 22 Field curvature curve of the optical lens in Embodiment 6 of the present application.

[0046] Figure 23 F-Tan(Theta) distortion curve of the optical lens in Embodiment 6 of the present application.

[0047] Figure 24 MTF curve of the optical lens in Embodiment 6 of the present application.

[0048] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0049] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It is to be understood that the detailed description is merely descriptive of embodiments of the present application and is not intended to limit the scope of the present application in any way. Throughout the description, like reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0050] It is noted that, in this specification, the expressions first, second, third, etc. are merely used to distinguish one feature from another feature, and do not indicate any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0051] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for the sake of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0052] In this specification, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0053] It should also be understood that the use of the terms "have", "has", "having", "include", "includes", "including", "comprise", "comprises" and / or "comprising", when appearing in the specification, is taken as referring to the existence of the stated features, elements and / or components, but does not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof. Further, the phrase "at least one of' followed by a list of two or more items, such as "at least one of A and B", should be interpreted to mean that A or B or both A and B are present. Further, the phrase "one or more of' followed by a list of two or more items, such as "one or more of A, B and C", should be interpreted to mean that A, B, C or any combination thereof is present. Further, the phrase "one or more of' followed by a list of two or more items, such as "one or more of A, B and C", should be interpreted to mean that A, B, C or any combination thereof is present. Any reference to "an implementation" or "one implementation" means that a particular feature, structure, or characteristic described in connection with the implementation is included in at least one implementation. Further, the appearance of a phrase in the specification in no way limits the scope of the application to the string of words merely reading the phrase. For example, a description of "building a structure" includes not only the literal process of building the structure, but also the process of constructing the structure, assembling the structure, fabricating the structure, and so on.

[0054] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0055] It should be noted that the embodiments and features of the application disclosed in the specification can be combined with each other, unless specifically stated otherwise. The application will be described in further detail below with reference to the drawings and embodiments.

[0056] The optical lens provided by the embodiments of the application comprises six lenses, which are sequentially arranged along an optical axis from an object side to an imaging surface as a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens.

[0057] In some embodiments, the first lens has a negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface. The second lens can have a positive focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which can be a concave surface or a convex surface. The third lens has a positive focal power, the object side surface of which is a convex surface, and the image side surface of which can be a concave surface or a convex surface. The fourth lens can have a negative focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface. The fifth lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which can be a concave surface or a convex surface. The sixth lens can have a negative focal power, the image side surface of which is a concave surface.

[0058] In some embodiments, the optical lens can further comprise a diaphragm, which can be located between the first lens and the second lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging. When the diaphragm is located between the first lens and the second lens, the correction of the diaphragm aberration is facilitated.

[0059] In some embodiments, the optical lens can further include a filter, which can be disposed between the sixth lens and the imaging surface. The filter is used to filter out interference light, preventing the interference light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0060] In some embodiments, the third lens and the fourth lens can be cemented to form a cemented lens, which can effectively correct chromatic aberration of the optical lens, reduce sensitivity of the optical lens to decentration, balance aberration of the optical lens, and improve imaging quality of the optical lens; and can also reduce assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0061] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.5 < TTL / f < 2.3. Satisfying the above range is conducive to limiting the total length of the lens while better realizing the long-focus performance of the system.

[0062] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV, and the real image height IH corresponding to the maximum field of view satisfy: 0.95 < (IH / 2) / (f x tan(FOV / 2)) < 1.05. Satisfying the above range can control the size of distortion and improve the imaging quality of the optical lens.

[0063] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 0.55 < IH / f < 0.7. Satisfying the above range controls the image height and focal length of the optical lens within a reasonable range, which helps the optical lens to have the characteristics of a large image surface and improve the imaging quality.

[0064] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.2 < BFL / f < 0.45. Satisfying the above range limits the optical lens to have a suitable back focus, facilitates reasonable arrangement of the positions of the lenses, and reduces the difficulty of processing and assembly.

[0065] In some embodiments, the total optical length TTL of the optical lens, the maximum field of view FOV of the optical lens, and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 45 < 180° x TTL / (IH / 2) / (FOV / 2) < 80. Satisfying the above range is conducive to balancing the relationship among the total length, the image height, and the field of view of the optical lens.

[0066] In some embodiments, the total track length TTL of the optical lens and the sum of the central thicknesses of the first lens to the sixth lens along the optical axis respectively, ∑CT, satisfy: 0.5 < ∑CT / TTL < 0.75. Satisfying the above range, reasonably configuring the total track length of the optical lens and the sum of the thicknesses of the lenses, helps to achieve high pixel characteristics and improve the imaging quality of the optical lens.

[0067] In some embodiments, the object-side aperture diameter D1 of the first lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 3 < D1 / IH / Tan(FOV / 2) < 4. Satisfying the above range can balance the relationship among the front aperture, the field of view angle, and the image size of the optical lens, which is conducive to miniaturization.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -2.8 < f1 / f < -1.8. Satisfying the above range can make the first lens have a negative refractive power, which is conducive to reducing the inclination angle of the incident light and collecting the edge field of view light into the rear optical lens as much as possible to achieve large-angle light collection.

[0069] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: f2 / f > 1.5. Satisfying the above range limits the second lens to have an appropriate positive refractive power, which is conducive to the convergence of light, makes the divergent light entering the system from the front smoothly enter the rear optical system, and the light trend is more gentle, optimizes aberration, and improves resolution.

[0070] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.6 < f3 / f < 1.4. Satisfying the above range limits the third lens to have an appropriate positive refractive power, which can effectively correct the aberration generated at the front end of the lens and improve the imaging quality of the lens.

[0071] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -1.9 < f4 / f < -1.2. Satisfying the above range limits the fourth lens to have an appropriate negative refractive power, which helps to increase the imaging area and improve the imaging quality.

[0072] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.6 < f5 / f < 1.2. Satisfying the above range limits the fifth lens to have an appropriate positive refractive power, which helps to reduce the aberration of the optical lens.

[0073] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -1.3 < f6 / f < -0.4. Satisfying the above range, the sixth lens is limited to have appropriate negative refractive power, which is beneficial to increase the imaging area of the optical lens, while the chromatic aberration of the optical lens can be optimized, and the imaging quality of the optical lens is improved.

[0074] In some embodiments, the effective focal length f of the optical lens and the object side surface curvature radius R5 of the third lens satisfy: 0.6 < R5 / f < 1.2. Satisfying the above range, the object side surface shape of the third lens is controlled, which can reduce the light deflection angle and make the light trend more stable, thereby improving the imaging quality of the optical lens.

[0075] In some embodiments, the effective focal length f of the optical lens and the object side surface curvature radius R9 of the fifth lens satisfy: 0.4 < R9 / f < 1.1. Satisfying the above range, the object side surface shape of the fifth lens is reasonably limited, which is beneficial to reduce the distortion generated by the front end lens, and at the same time, the difficulty of distortion correction of the rear end lens is reduced.

[0076] In some embodiments, the effective focal length f of the optical lens and the image side surface curvature radius R12 of the sixth lens satisfy: 0.3 < R12 / f < 0.6. Satisfying the above range, the image side surface shape of the sixth lens is reasonably limited, which is beneficial to increase the imaging area.

[0077] In some embodiments, the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy: -0.6 < (R1-R2) / (R1+R2) < -0.2. Satisfying the above range, the deflection degree of light passing through the first lens is alleviated, and the difficulty of aberration correction of the subsequent lens is reduced.

[0078] In some embodiments, the object side surface curvature radius R7 of the fourth lens and the image side surface curvature radius R8 of the fourth lens satisfy: -0.9 < (R7-R8) / (R7+R8) < -0.6. Satisfying the above range, the aberration can be effectively corrected, and the imaging quality of the optical lens is improved.

[0079] In some embodiments, the optical lens satisfies the following conditional expressions: 14mm < f < 16mm; 30° < FOV < 40°; 9mm < EPD < 10mm; 23mm < TTL < 33mm; 1.5 < Fno < 1.8; 9mm < IH < 10mm; 19° < CRA < 23°; 4mm < BFL < 6.5mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray angle of incidence of the optical lens, and BFL represents the back focal length of the optical lens. By satisfying the above ranges, the optical lens has one or more advantages such as a large target surface, a large aperture, and a long focal length.

[0080] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The optical lens provided by the present application can adopt a full-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0081] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens can adopt a spherical lens or an aspherical lens. Compared with a spherical structure, an aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization. More specifically, the first lens, the third lens, the fourth lens, and the fifth lens of the present application adopt a spherical lens, and the second lens and the sixth lens adopt an aspherical lens.

[0082] In various embodiments of the present application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[0083] ;

[0084] wherein z is the distance of the curved surface from the vertex of the curved surface in the direction of the optical axis, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic surface coefficient, and B, C, D, E, and F are the fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients, respectively.

[0085] The application will be further described in the following embodiments. In each embodiment, the thickness, the radius of curvature, the material selection of each lens in the optical lens are different, and the specific differences can be referred to the parameter table of each embodiment. The following embodiments are only the preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, any changes, substitutions, combinations or simplifications made without departing from the innovative points of the application should be regarded as equivalent replacement, and are included in the protection scope of the application.

[0086] Embodiment 1

[0087] Please refer to Figure 1 , which is a structural schematic diagram of the optical lens provided in the embodiment 1 of the application, the optical lens includes, along the optical axis from the object side to the imaging surface, a first lens L1, a stop ST, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a filter G1.

[0088] The first lens L1 has a negative focal power, the object side S1 thereof is a concave surface, and the image side S2 thereof is a convex surface;

[0089] The second lens L2 has a positive focal power, the object side S3 thereof is a convex surface, and the image side S4 thereof is a concave surface;

[0090] The third lens L3 has a positive focal power, the object side S5 and the image side S6 thereof are both convex surfaces;

[0091] The fourth lens L4 has a negative focal power, the object side S6 thereof is a concave surface, and the image side S7 thereof is a convex surface;

[0092] The third lens L3 and the fourth lens L4 form a cemented lens group, that is, the cemented surface of the image side of the third lens L3 and the object side of the fourth lens L4 is S6;

[0093] The fifth lens L5 has a positive focal power, the object side S8 and the image side S9 thereof are both convex surfaces;

[0094] The sixth lens L6 has a negative focal power, the object side S10 and the image side S11 thereof are both concave surfaces;

[0095] The object side S12 and the image side S13 of the filter G1 are both flat surfaces;

[0096] The imaging surface S14 is a flat surface.

[0097] The second lens L2 and the sixth lens L6 are glass aspheric lenses, and the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are glass spherical lenses.

[0098] The related parameters of each lens in the optical lens in the embodiment 1 are shown in Table 1-1.

[0099] Table 1-1

[0100]

[0101] The surface parameters of the aspherical lens of the optical lens in Example 1 are shown in Table 1-2.

[0102] Table 1-2

[0103]

[0104] In this embodiment, the field curvature curve, F-Tan(Theta) distortion curve and MTF curve of the optical lens are shown in Figure 2 、 Figure 3 、 Figure 4 respectively.

[0105] Figure 2 The field curvature curve of Example 1 is shown, which represents the curvature degree of light rays of different wavelengths on the meridional image surface and the sagittal image surface, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.06 mm, which shows that the optical lens can well correct the field curvature.

[0106] Figure 3 The F-Tan(Theta) distortion curve of Example 1 is shown, which represents the distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within -2%~0, the image compression in the edge angle region is relatively flat, and the clarity of the unfolded image is effectively improved.

[0107] Figure 4 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that the MTF value of this embodiment is above 0.28 in the full field of view, and in the range of 0~120 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0108] Example 2

[0109] Please refer to Figure 5The figure shows a schematic diagram of the optical lens provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S3 of the second lens L2 is concave; the image side surface S4 of the second lens L2 is convex; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0110] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2-1.

[0111] Table 2-1

[0112]

[0113] The surface profile parameters of the aspherical lens in Example 2 are shown in Table 2-2.

[0114] Table 2-2

[0115]

[0116] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, and MTF curve of the optical lens are respectively as follows: Figure 6 , Figure 7 , Figure 8 As shown.

[0117] from Figure 6 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.05mm, indicating that the optical lens can effectively correct the field curvature.

[0118] from Figure 7 As can be seen, the distortion of the optical lens is controlled within 0-1%, indicating that the optical lens can effectively correct distortion.

[0119] from Figure 8 As can be seen, the MTF value of this embodiment is above 0.28 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0120] Example 3

[0121] Please see Figure 9 The figure shows a schematic diagram of the optical lens provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the image side S9 of the fifth lens L5 is concave, the object side S10 of the sixth lens L6 is convex, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0122] The relevant parameters of each lens in the optical lens of Example 3 are shown in Table 3-1.

[0123] Table 3-1

[0124]

[0125] The surface shape parameters of the aspherical lens of the optical lens in Embodiment 3 are shown in Table 3-2.

[0126] Table 3-2

[0127]

[0128] In this embodiment, the field curvature curve, F-Tan(Theta) distortion curve and MTF curve of the optical lens are shown in Figure 10 , Figure 11 , Figure 12 respectively.

[0129] As can be seen from Figure 10 , the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.1 mm, which shows that the optical lens can well correct the field curvature.

[0130] As can be seen from Figure 11 , the distortion of the optical lens is controlled within ±0.5%, which shows that the optical lens can well correct the distortion.

[0131] As can be seen from Figure 12 , the MTF value of this embodiment is above 0.3 in the full field of view, and in the range of 0-120 lp / mm, the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0132] Embodiment 4

[0133] Please refer to Figure 13 , which is a structural schematic diagram of the optical lens provided in Embodiment 4 of the present application, and compared with Embodiment 1, the main difference is that: the image side surface S9 of the fifth lens L5 is a concave surface; the object side surface S10 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0134] The related parameters of each lens in the optical lens in Embodiment 4 are shown in Table 4-1.

[0135] Table 4-1

[0136]

[0137] The surface shape parameters of the aspherical lens of the optical lens in Embodiment 4 are shown in Table 4-2.

[0138] Table 4-2

[0139]

[0140] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are shown in Figure 14 、 Figure 15 、 Figure 16 respectively.

[0141] As can be seen from Figure 14 , the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.1mm, which indicates that the optical lens can well correct the field curvature.

[0142] As can be seen from Figure 15 , the distortion of the optical lens is controlled within ±0.5%, which indicates that the optical lens can well correct the distortion.

[0143] As can be seen from Figure 16 , the MTF value of the optical lens in the embodiment is above 0.28 in the full field of view, and in the range of 0-120lp / mm, the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view, and the optical lens has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0144] Embodiment 5

[0145] Please refer to Figure 17 , which is a structural schematic diagram of the optical lens provided in the embodiment 5 of the present application, and the main difference between the embodiment and the embodiment 1 is that the third lens L3 and the fourth lens L4 are not cemented lenses; the image side surface S4 of the second lens L2 is a convex surface; the image side surface S6 of the third lens L3 is a concave surface; the object side surface S11 of the sixth lens L6 is a convex surface; the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0146] The related parameters of each lens in the optical lens in the embodiment 5 are shown in Table 5-1.

[0147] Table 5-1

[0148]

[0149] The surface type parameters of the aspherical lens of the optical lens in the embodiment 5 are shown in Table 5-2.

[0150] Table 5-2

[0151]

[0152] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are shown in Figure 18 ,Figure 19 , Figure 10 As shown.

[0153] from Figure 18 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.15mm, indicating that the optical lens can effectively correct the field curvature.

[0154] from Figure 19 As can be seen, the distortion of the optical lens is controlled within 0-4%, indicating that the optical lens can effectively correct distortion.

[0155] from Figure 20 As can be seen, the MTF value of this embodiment is above 0.2 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0156] Example 6

[0157] Please see Figure 21 The figure shows a schematic diagram of the optical lens provided in Embodiment 6 of the present invention. The main difference between this embodiment and Embodiment 1 is that the third lens L3 and the fourth lens L4 are not cemented lenses; the image-side surface S4 of the second lens L2 is convex; the image-side surface S6 of the third lens L3 is concave; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0158] The relevant parameters of each lens in the optical lens of Example 6 are shown in Table 6-1.

[0159] Table 6-1

[0160]

[0161] The surface profile parameters of the aspherical lens in Example 6 are shown in Table 6-2.

[0162] Table 6-2

[0163]

[0164] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, and MTF curve of the optical lens are respectively as follows: Figure 22 , Figure 23 , Figure 24 As shown.

[0165] from Figure 22 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens can effectively correct the field curvature.

[0166] fromFigure 23 As can be seen from the above table, the distortion of the optical lens is controlled within -2%~0, which indicates that the optical lens can well correct the distortion.

[0167] From the above table, it can be seen that the MTF value of the optical lens is above 0.3 in the full field of view, and the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view in the range of 0~120lp / mm, and the imaging quality and the detail resolution capability are good in the low frequency and high frequency cases. Figure 24

[0168] Please refer to Table 7 for the optical properties corresponding to the above embodiments, including the effective focal length f, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the maximum field of view angle FOV of the optical lens, and the numerical value corresponding to each conditional expression in each embodiment.

[0169] Table 7

[0170]

[0171] In summary of the above embodiments, the optical lens provided by the present application adopts six lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as large target surface, large aperture, high imaging quality, etc.

[0172] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0173] The above described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.​

Claims

1. An optical lens, six pieces of lenses in total, characterized in that, In order from the object side to the imaging plane along the optical axis, successively comprises: a first lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a second lens with positive refractive power; a third lens with positive refractive power, the object side surface of which is a convex surface; a fourth lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a fifth lens with positive refractive power, the object side surface of which is a convex surface; a sixth lens with negative refractive power, the image side surface of which is a concave surface; An optical total length TTL of the optical lens and an effective focal length f of the optical lens satisfy: 1.5 < TTL / f < 2.3; An object side surface aperture D1 of the first lens, a real image height IH corresponding to a maximum field angle of view FOV of the optical lens, and the maximum field angle of view FOV of the optical lens satisfy: 3 < D1 / IH / Tan(FOV / 2) < 4; An effective focal length f of the optical lens satisfies: 14 mm < f < 16 mm; An effective focal length f of the optical lens and a focal length f4 of the fourth lens satisfy: -1.9 < f4 / f < -1.

2.

2. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a back focal length BFL of the optical lens satisfy: 0.2 < BFL / f < 0.

45.

3. The optical lens of claim 1, wherein, A real image height IH corresponding to a maximum field angle of view of the optical lens and an effective focal length f of the optical lens satisfy: 0.55 < IH / f < 0.

7.

4. The optical lens of claim 1, wherein, An optical total length TTL of the optical lens, a maximum field angle of view FOV of the optical lens, and a real image height IH corresponding to the maximum field angle of view of the optical lens satisfy: 45 < 180°×TTL / (IH / 2) / (FOV / 2) < 80.

5. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a focal length f1 of the first lens satisfy: -2.8 < f1 / f < -1.8, and the effective focal length f of the optical lens and a focal length f3 of the third lens satisfy: 0.6 < f3 / f < 1.

4.

6. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a radius of curvature R5 of the object side surface of the third lens satisfy: 0.6 < R5 / f < 1.

2.

7. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a radius of curvature R9 of the object side surface of the fifth lens satisfy: 0.4 < R9 / f < 1.

1.

8. The optical lens of claim 1, wherein, An effective focal length f of the optical lens and a radius of curvature R12 of the image side surface of the sixth lens satisfy: 0.3 < R12 / f < 0.

6.

9. The optical lens of claim 1, wherein, A radius of curvature R1 of the object side surface of the first lens and a radius of curvature R2 of the image side surface of the first lens satisfy: -0.6 < (R1-R2) / (R1+R2) < -0.

2.

10. The optical lens of claim 1, wherein, A radius of curvature R7 of the object side surface of the fourth lens and a radius of curvature R8 of the image side surface of the fourth lens satisfy: -0.9 < (R7-R8) / (R7+R8) < -0.6.

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