Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses arranged along an optical axis from an object side to an imaging surface in sequence, wherein the seven lenses are: a first lens with negative focal power, the object side surface of which is a concave surface and the image side surface of which is a concave surface; a second lens with positive focal power; a third lens with positive focal power, the object side surface of which is a convex surface and the image side surface of which is a convex surface; a fourth lens with positive focal power, the object side surface of which is a convex surface; a fifth lens with negative focal power; a sixth lens with positive focal power; and a seventh lens with negative focal power, the object side surface of which is a convex surface near the optical axis and the image side surface of which is a concave surface near the optical axis; wherein the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy 3.0 < IH / EPD < 3.5. The optical lens provided by the application has the advantages of large field of view, large aperture and miniaturization.

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 development of automobile intelligence, the driving assistance function of vehicles is gradually enhanced, and the visual information collection is the core tool. With the improvement of the level of automatic driving, the requirements for vehicle-mounted cameras are also gradually improved, especially for front cameras. The front camera can enhance the active safety and driver assistance function, such as automatic emergency braking (AEB), adaptive cruise control (ACC), lane keeping assistance system (LKAS) and traffic jam assistance (TJA), etc. The front camera has the advantages of meeting high resolution, large field of view, good environmental adaptability, etc., but also has the disadvantages of too many lenses and too long total optical length, which is not conducive to the miniaturization of electronic systems. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens which can solve one or more of the above problems.

[0004] To achieve the above purpose, the technical scheme of the present application is as follows:

[0005] An optical lens, a total of seven lenses, along the optical axis from the object side to the imaging surface in order: a first lens with negative focal power, the object side is concave, the image side is concave; a second lens with positive focal power; a third lens with positive focal power, the object side is convex, the image side is convex; a fourth lens with positive focal power, the object side is convex; a fifth lens with negative focal power; a sixth lens with positive focal power; a seventh lens with negative focal power, the object side is convex at the near optical axis, the image side is concave at the near optical axis; wherein the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 3.0 < IH / EPD < 3.5.

[0006] In some embodiments, the object side of the second lens is concave, and the image side is convex.

[0007] In some embodiments, the object side of the second lens is convex, and the image side is concave.

[0008] In some embodiments, the object side of the fourth lens is convex, and the image side is convex.

[0009] In some embodiments, the object side of the fifth lens is concave, and the image side is concave.

[0010] In some embodiments, the object side of the sixth lens is convex.

[0011] In some embodiments, the image-side surface of the sixth lens is a concave surface.

[0012] In some embodiments, the image-side surface of the sixth lens is a convex surface.

[0013] In some embodiments, the fourth lens and the fifth lens are cemented to form a cemented lens.

[0014] In some embodiments, the fourth lens, the fifth lens and the sixth lens are cemented to form a cemented lens.

[0015] In some embodiments, the second lens and the seventh lens have aspheric surfaces.

[0016] In some embodiments, a diaphragm is further arranged between the second lens and the third lens.

[0017] In some embodiments, a diaphragm is further arranged between the first lens and the second lens.

[0018] In some embodiments, the maximum field of view FOV of the optical lens and the F-number FNO of the optical lens satisfy: 85° < FOV / FNO.

[0019] In some embodiments, the total track length TTL of the optical lens and the real image height IH corresponding to the maximum field of view of the optical lens satisfy: 3.2 < TTL / IH < 3.5.

[0020] In some embodiments, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.2 < TTL / f < 6.8.

[0021] In some embodiments, the effective aperture D1 of the object-side surface of the first lens, the real image height IH corresponding to the maximum field of view of the optical lens, and the maximum half field of view θ of the optical lens satisfy: 0.4 < D1 / IH / tan(θ) < 0.6.

[0022] In some embodiments, the total track length TTL of the optical lens and the sum of the center thickness CT4 of the fourth lens, the center thickness CT5 of the fifth lens, and the center thickness CT6 of the sixth lens satisfy: 0.1 < (CT4+CT5+CT6) / TTL < 0.3.

[0023] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R1 of the object-side surface of the first lens satisfy: R1 / f < -15.0.

[0024] In some embodiments, the optical back focal length BFL of the optical lens and the total track length TTL of the optical lens satisfy: 0.05 < BFL / TTL < 0.12.

[0025] In some embodiments, the effective focal length f of the optical lens and the effective focal length f1 of the first lens satisfy: -2.0

[0026] In some embodiments, the effective focal length f of the optical lens and the effective focal length f2 of the second lens satisfy: 2.3

[0027] In some embodiments, the effective focal length f of the optical lens and the effective focal length f3 of the third lens satisfy: 2.0

[0028] Compared with the prior art, the beneficial effects of the present application are: through reasonable collocation of the lens shape and the optical power combination between each lens, the effects of large field of view, large aperture and miniaturization are realized. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a structure schematic diagram of the optical lens of the embodiment 1 of the present application.

[0030] Figure 2 It is a field curvature curve diagram of the optical lens in the embodiment 1 of the present application.

[0031] Figure 3 It is a relative luminance curve diagram of the optical lens in the embodiment 1 of the present application.

[0032] Figure 4 It is an MTF curve diagram of the optical lens in the embodiment 1 of the present application.

[0033] Figure 5 It is an axial aberration curve diagram of the optical lens in the embodiment 1 of the present application.

[0034] Figure 6 It is a curve diagram of the optical lens in the embodiment 1 of the present application. The relative luminance curve diagram of the optical lens in the embodiment 1 of the present application.

[0035] Figure 7 It is a structure schematic diagram of the optical lens of the embodiment 2 of the present application.

[0036] Figure 8 It is a field curvature curve diagram of the optical lens in the embodiment 2 of the present application.

[0037] Figure 9 It is a relative luminance curve diagram of the optical lens in the embodiment 2 of the present application.

[0038] Figure 10 It is an MTF curve diagram of the optical lens in the embodiment 2 of the present application.

[0039] Figure 11 It is an axial aberration curve diagram of the optical lens in the embodiment 2 of the present application.

[0040] Figure 12 The vertical axis chromatic aberration curve of the optical lens in Embodiment 2 of the present application.

[0041] Figure 13 The structural schematic diagram of the optical lens in Embodiment 3 of the present application.

[0042] Figure 14 The field curvature curve of the optical lens in Embodiment 3 of the present application.

[0043] Figure 15 The relative luminance curve of the optical lens in Embodiment 3 of the present application.

[0044] Figure 16 The MTF curve of the optical lens in Embodiment 3 of the present application.

[0045] Figure 17 The axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0046] Figure 18 The vertical axis chromatic aberration curve of the optical lens in Embodiment 3 of the present application.

[0047] Figure 19 The structural schematic diagram of the optical lens in Embodiment 4 of the present application.

[0048] Figure 20 The field curvature curve of the optical lens in Embodiment 4 of the present application.

[0049] Figure 21 The relative luminance curve of the optical lens in Embodiment 4 of the present application.

[0050] Figure 22 The MTF curve of the optical lens in Embodiment 4 of the present application.

[0051] Figure 23 The axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0052] Figure 24 The vertical axis chromatic aberration curve of the optical lens in Embodiment 4 of the present application.

[0053] Figure 25 The structural schematic diagram of the optical lens in Embodiment 5 of the present application.

[0054] Figure 26 The field curvature curve of the optical lens in Embodiment 5 of the present application.

[0055] Figure 27 The relative luminance curve of the optical lens in Embodiment 5 of the present application.

[0056] Figure 28MTF curve diagram of the optical lens in Embodiment 5 of the present application.

[0057] Figure 29 Axial aberration curve diagram of the optical lens in Embodiment 5 of the present application.

[0058] Figure 30 Vignetting curve diagram of the optical lens in Embodiment 5 of the present application. DETAILED DESCRIPTION

[0059] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be noted that these detailed descriptions are only examples of embodiments of the present application and are not intended in any way to restrict the scope of the present application. Throughout the specification, 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.

[0060] It is to be noted that, in the present specification, the expressions first, second, third and the like are used only to distinguish one feature from another feature, and do not denote any limitation on the features. Thus, 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.

[0061] 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.

[0062] In the present 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 image plane is referred to as the image side surface of the lens.

[0063] It is also to be understood that the use of the terms "include", "includes", "including", "has", "have", "has", "having", or "comprises" or "comprising", when used in this specification, specifies the presence of the stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. In addition, when expressions such as "at least one of... " appear after the list of one or more features, the expression "at least one of... " modifies the entire list of features, and not the individual elements of the list. Furthermore, when describing embodiments of the present application, the use of "may" indicates that one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

[0064] 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 idealized or overly formal sense unless expressly so defined herein.

[0065] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0066] An optical lens is provided in the embodiments of the present application, which comprises, in sequence from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and a filter and a protective glass.

[0067] The first lens has a negative focal power, and its object side surface is concave and its image side surface is concave; the second lens has a positive focal power, and its object side surface is convex or concave and its image side surface is concave or convex; the third lens has a positive focal power, and its object side surface is convex and its image side surface is convex; the fourth lens has a positive focal power, and its object side surface is convex and its image side surface is convex; the fifth lens has a negative focal power, and its object side surface is concave and its image side surface is concave; the sixth lens has a positive focal power, and its object side surface is convex and its image side surface is convex or concave; and the seventh lens has a negative focal power, and its object side surface is convex and its image side surface is concave.

[0068] In some embodiments, the fourth lens and the fifth lens can be cemented to form a cemented lens, or the fourth lens, the fifth lens and the sixth lens can be cemented to form a cemented lens, so as to share the chromatic aberration correction of the optical lens, improve the resolution of the optical lens, and at the same time make the structure of the optical lens compact, which is conducive to the miniaturization of the optical lens.

[0069] In some embodiments, a diaphragm can be arranged between the second lens and the third lens and near the object side surface of the third lens, or a diaphragm can be arranged between the first lens and the second lens and near the object side surface of the second lens, so as to converge the range of the light rays emitted from the front end of the optical lens and reduce the rear end aperture of the optical lens.

[0070] In some embodiments, the aperture value FNO of the optical lens satisfies 1.60≤FNO. Satisfying the above range is conducive to realizing the large aperture characteristic, and can ensure the clarity of the image in a weak light environment or at night.

[0071] In some embodiments, the maximum half field angle θ of the optical lens satisfies: 65° < θ. Satisfying the above range is conducive to achieving wide-angle characteristics, thereby being able to obtain more scene information and meeting the requirement of wide-range detection.

[0072] In some embodiments, the maximum field angle chief ray angle CRA on the image plane of the optical lens satisfies: 10° < CRA < 30°. Satisfying the above range can make the CRA of the optical lens have a larger allowable error range with the CRA of the chip photosensitive element, thereby improving the adaptation capability of the optical lens to the image sensor.

[0073] In some embodiments, the maximum field angle corresponding real image height IH and entrance pupil diameter EPD of the optical lens satisfy: 3.0 < IH / EPD < 3.5. Satisfying the above range can make the width of the light beam entering the optical lens as large as possible under different field angles, so that the brightness of the optical lens at the image plane is improved to avoid the generation of dark corners, and the imaging area of the optical lens is increased.

[0074] In some embodiments, the maximum field angle FOV and the aperture value FNO of the optical lens satisfy: 85° < FOV / FNO. Satisfying the above range is conducive to expanding the field angle of the optical lens and increasing the aperture of the optical lens, thereby achieving wide-angle and large-aperture characteristics. The implementation of the wide-angle characteristic is conducive to the optical lens obtaining more scene information and meeting the requirement of wide-range detection, and the implementation of the large-aperture characteristic is conducive to improving the problem of the relative brightness of the edge field of view decreasing rapidly caused by the wide-angle, thereby also being conducive to obtaining more scene information.

[0075] In some embodiments, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field angle satisfy: 3.2 < TTL / IH < 3.5. Satisfying the above range is conducive to balancing the total length and imaging quality of the optical lens.

[0076] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f satisfy: 6.2 < TTL / f < 6.8. Satisfying the above range can effectively limit the length and volume of the optical lens, thereby realizing the miniaturization of the optical lens.

[0077] In some embodiments, the effective aperture D1 of the first lens object side, the real image height IH corresponding to the maximum field angle, and the maximum half field angle θ satisfy: 0.4 < D1 / IH / tan(θ) < 0.6. Satisfying the above range is conducive to reducing the front aperture of the optical lens, thereby realizing the miniaturization of the optical lens.

[0078] In some embodiments, the optical total track length TTL of the optical lens and the sum of the center thickness CT4 of the fourth lens, the center thickness CT5 of the fifth lens, and the center thickness CT6 of the sixth lens satisfy: 0.1 < (CT4+CT5+CT6) / TTL < 0.3. Satisfying the above range can make the structure of the optical lens compact, which is conducive to the miniaturization of the optical lens, and at the same time, the light can smoothly enter, and the illumination of the optical lens is improved.

[0079] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R1 of the object side surface of the first lens satisfy: R1 / f < -15.0. Satisfying the above range can effectively control the surface curvature of the object side surface of the first lens, increase the field of view angle, and control the front aperture of the optical lens.

[0080] In some embodiments, the optical back focal length BFL of the optical lens and the optical total track length TTL satisfy: 0.05 < BFL / TTL < 0.12. Satisfying the above range can make the optical lens have a larger optical back focal length, which is conducive to reducing the interference between the lens and the imaging chip, thereby reducing the correction difficulty of the CRA.

[0081] In some embodiments, the effective focal length f of the optical lens and the effective focal length f1 of the first lens satisfy: -2.0 < f1 / f < -1.0. Satisfying the above range can make the first lens have an appropriate negative focal length, which is conducive to the change of the incident light refraction angle being relatively moderate, avoids the change of the refraction angle being too strong to produce too much aberration, and at the same time, helps more light to enter the rear optical system, increases the illumination, and improves the imaging quality of the optical lens.

[0082] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 2.3 < f2 / f < 8.0. Satisfying the above range can make the second lens have an appropriate positive focal length, and by reasonably limiting the focal length of the second lens, the off-axis aberration caused by the first lens can be corrected, and the imaging quality of the optical lens is improved.

[0083] In some embodiments, the effective focal length f of the optical lens and the effective focal length f3 of the third lens satisfy: 2.0 < f3 / f < 3.0. Satisfying the above range can make the third lens have an appropriate positive focal length, which is conducive to the smooth transition of the light path, and improves the imaging quality of the optical lens.

[0084] In order to make the system have better optical performance, a plurality of aspherical lenses are used in the lens, and the shape of each aspherical surface of the optical lens satisfies the following equation:

[0085]

[0086] Wherein, z is the distance of the curved surface and the vertex of the curved surface in the direction of the optical axis, h is the distance of the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic curved surface coefficient, A, B, C, D, E, F are the second order, fourth order, sixth order, eighth order, tenth order and twelfth order curved surface coefficients respectively.

[0087] 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 all are included in the protection scope of the application.

[0088] Embodiment 1

[0089] 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 comprises, along the optical axis from the object side to the imaging surface S18, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0090] Wherein, the first lens L1 has negative focal power, the object side S1 is a concave surface, and the image side S2 is a concave surface; the second lens L2 has positive focal power, the object side S3 is a concave surface, and the image side S4 is a convex surface; the third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side S6 is a convex surface; the fourth lens L4 has positive focal power, the object side S7 is a convex surface, and the image side is a convex surface; the fifth lens L5 has negative focal power, the object side is a concave surface, and the image side S9 is a concave surface, and the fourth lens L4 and the fifth lens L5 are cemented to form a cemented lens, and the cemented surface is S8; the sixth lens L6 has positive focal power, the object side S10 is a convex surface, and the image side S11 is a concave surface; the seventh lens L7 has negative focal power, the object side S12 is a convex surface at the near optical axis, and the image side S13 is a concave surface at the near optical axis; the filter G1, the object side S14 and the image side S15 are both flat surfaces; the protective glass G2, the object side S16 and the image side S17 are both flat surfaces.

[0091] The related parameters of each lens in the optical lens in the embodiment 1 are shown in Table 1-1.

[0092] Table 1-1

[0093]

[0094]

[0095] The curve coefficients of the aspherical lens of the optical lens in embodiment 1 are shown in Table 1-2.

[0096] Table 1-2

[0097]

[0098] Figure 2 The field curvature curve of embodiment 1 is shown, which represents the bending degree of the meridional image surface and the sagittal image surface of light rays of different wavelengths, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.025 mm, which shows that the optical lens can correct the field curvature very well.

[0099] Figure 3 The relative illumination curve of embodiment 1 is shown, which represents the relative illumination value of different field angles on the imaging surface, the horizontal axis represents the half field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 70% at the maximum half field angle, which shows that the optical lens has very good relative illumination.

[0100] Figure 4 The modulation transfer function (MTF) curve of embodiment 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. As can be seen from the figure, the MTF value of the embodiment is above 0.4 within the full field of view, and in the range of 0-160 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in low frequency and high frequency cases.

[0101] Figure 5 The axial aberration curve of embodiment 1 is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within ±10 μm, which shows that the optical lens can correct the axial aberration well.

[0102] Figure 6 The axial aberration curve of embodiment 1 is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: μm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the axial aberration is controlled within ±10 μm, which shows that the optical lens can correct the axial aberration well.

[0103] Example 2

[0104] Please see Figure 7 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 2 of the present invention. The optical lens includes, along the optical axis from the object side to the imaging surface S18, the following components in sequence: a first lens L1, a second lens L2, an aperture ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0105] Among them, the first lens L1 has negative optical power, with its object-side surface S1 being concave and its image-side surface S2 being concave; the second lens L2 has positive optical power, with its object-side surface S3 being concave and its image-side surface S4 being convex; the third lens L3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being convex; the fourth lens L4 has positive optical power, with its object-side surface S7 being convex and its image-side surface being convex; and the fifth lens L5 has negative optical power, with its object-side surface being concave and its image-side surface S9 being concave. Furthermore, the fourth lens L4 and the fifth lens L5 are cemented together to form a cemented lens, with the cementing surface being S8; the sixth lens L6 has positive optical power, with its object-side surface S10 being convex and its image-side surface S11 being convex; the seventh lens L7 has negative optical power, with its object-side surface S12 being convex near the optical axis and its image-side surface S13 being concave near the optical axis; the filter G1 has both its object-side surface S14 and its image-side surface S15 being flat; and the protective glass G2 has both its object-side surface S16 and its image-side surface S17 being flat.

[0106] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2-1.

[0107] Table 2-1

[0108]

[0109]

[0110] The surface coefficients of the aspherical lens in the optical lens of Example 2 are shown in Table 2-2.

[0111] Table 2-2

[0112]

[0113] Figure 8 to Figure 12The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the axial chromatic aberration curve of the optical lens of embodiment 2 are shown in the figures. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.025 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 70% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is greater than 0.45 within the full field of view, and the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view within the range of 0-160 lp / mm, which indicates that the optical lens has good imaging quality and good detail resolution ability in the case of low frequency and high frequency; the offset of the axial aberration is controlled within ±17 μm, which indicates that the optical lens can correct the axial aberration well; the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1.5 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0114] Embodiment 3

[0115] Please refer to Figure 13 , which is a structural schematic diagram of the optical lens provided in embodiment 3 of the present application, and the optical lens comprises, along the optical axis from the object side to the imaging surface S18, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0116] The first lens L1 has negative focal power, the object side S1 is a concave surface, and the image side S2 is a concave surface; the second lens L2 has positive focal power, the object side S3 is a concave surface, and the image side S4 is a convex surface; the third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side S6 is a convex surface; the fourth lens L4 has positive focal power, the object side S7 is a convex surface, and the image side is a convex surface; the fifth lens L5 has negative focal power, the object side is a concave surface, and the image side S9 is a concave surface; the fourth lens L4 and the fifth lens L5 are cemented to form a cemented lens, and the cemented surface is S8; the sixth lens L6 has positive focal power, the object side S10 is a convex surface, and the image side S11 is a convex surface; the seventh lens L7 has negative focal power, the object side S12 is a convex surface near the optical axis, and the image side S13 is a concave surface near the optical axis; the filter G1 has a plane object side S14 and a plane image side S15; the protective glass G2 has a plane object side S16 and a plane image side S17.

[0117] The related parameters of the lenses in the optical lens of embodiment 3 are shown in Table 3-1.

[0118] Table 3-1

[0119]

[0120] The curve coefficients of the aspherical lens of the optical lens in embodiment 3 are shown in table 3-2.

[0121] Table 3-2

[0122]

[0123] Figure 14 to Figure 18 The field curvature curve, the relative illumination curve, the modulation transfer function (MTF) curve, the axial aberration curve and the transverse chromatic aberration curve of embodiment 3 are shown respectively. It can be seen from the figures that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.03 mm, which indicates that the optical lens can correct the field curvature very well; the relative illumination value of the optical lens is still greater than 70% at the maximum half field angle, which indicates that the optical lens has very good relative illumination; the MTF value of the optical lens is all above 0.4 within the full field of view, and in the range of 0-160 lp / 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; the offset of the axial aberration is controlled within ±15 μm, which indicates that the optical lens can correct the axial aberration well; the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3.2 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0124] Embodiment 4

[0125] Please refer to Figure 19 , which is a structural schematic diagram of the optical lens provided in embodiment 4 of the present application, and the optical lens comprises, along the optical axis from the object side to the imaging surface S17, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0126] The first lens L1 has negative focal power, the object side S1 is a concave surface, and the image side S2 is a concave surface; the second lens L2 has positive focal power, the object side S3 is a concave surface, and the image side S4 is a convex surface; the third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side S6 is a convex surface; the fourth lens L4 has positive focal power, the object side S7 is a convex surface, and the image side is a convex surface; the fifth lens L5 has negative focal power, the object side is a concave surface, and the image side is a concave surface; the sixth lens L6 has positive focal power, the object side is a convex surface, and the image side S10 is a convex surface; the fourth lens L4 and the fifth lens L5 and the sixth lens L6 are cemented to form a cemented lens, the cemented surface of the fourth lens L4 and the fifth lens L5 is S8, and the cemented surface of the fifth lens L5 and the sixth lens L6 is S9; the seventh lens L7 has negative focal power, the object side S11 is a convex surface at the near optical axis, and the image side S12 is a concave surface at the near optical axis; the filter G1 has a plane object side S13 and a plane image side S14; and the protective glass G2 has a plane object side S15 and a plane image side S16.

[0127] The related parameters of the lenses in the optical lens in Example 4 are shown in Table 4-1.

[0128] Table 4-1

[0129]

[0130] The surface coefficients of the aspherical lenses of the optical lens in Example 4 are shown in Table 4-2.

[0131] Table 4-2

[0132]

[0133] Figure 20 to Figure 24 The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the transverse chromatic aberration curve of Example 4 are shown respectively. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.022 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 70% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is greater than 0.45 in the full field of view, and in the range of 0-160 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 low frequency and high frequency conditions; the shift of the axial aberration is controlled within ±18 μm, which indicates that the optical lens can correct the axial aberration well; the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1.5 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0134] Embodiment 5

[0135] Referring to Figure 25 , a structural diagram of an optical lens provided in Embodiment 5 of the present application is shown, which comprises, along the optical axis from the object side to the imaging surface S17, a first lens L1, a diaphragm ST, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1 and a protective glass G2.

[0136] The first lens L1 has a negative focal length, the object side S1 is concave, and the image side S2 is concave; the second lens L2 has a positive focal length, the object side S3 is convex, and the image side S4 is concave; the third lens L3 has a positive focal length, the object side S5 is convex, and the image side S6 is convex; the fourth lens L4 has a positive focal length, the object side S7 is convex, and the image side is convex; the fifth lens L5 has a negative focal length, the object side is concave, and the image side is concave; the sixth lens L6 has a positive focal length, the object side is convex, and the image side S10 is concave at the near optical axis; the fourth lens L4 and the fifth lens L5 and the sixth lens L6 are cemented to form a cemented lens, the cemented surface of the fourth lens L4 and the fifth lens L5 is S8, and the cemented surface of the fifth lens L5 and the sixth lens L6 is S9; the seventh lens L7 has a negative focal length, the object side S11 is convex at the near optical axis, and the image side S12 is concave at the near optical axis; the filter G1 has a plane object side S13 and a plane image side S14; and the protective glass G2 has a plane object side S15 and a plane image side S16.

[0137] The related parameters of each lens in the optical lens in Embodiment 5 are shown in Table 5-1.

[0138] Table 5-1

[0139]

[0140]

[0141] The curve coefficients of the aspherical lenses of the optical lens in Embodiment 5 are shown in Table 5-2.

[0142] Table 5-2

[0143]

[0144] Figure 26 to Figure 30The field curvature curve, the relative luminance curve, the modulation transfer function (MTF) curve, the axial aberration curve and the axial chromatic aberration curve of the optical lens of embodiment 5 are shown respectively. As can be seen from the figures, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.045 mm, which indicates that the optical lens can correct the field curvature very well; the relative luminance value of the optical lens is still greater than 80% at the maximum half field angle, which indicates that the optical lens has very good relative luminance; the MTF value of the optical lens is all above 0.4 within the full field of view, and in the range of 0-160 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; the offset of the axial aberration is controlled within ±15 μm, which indicates that the optical lens can correct the axial aberration well; the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1.5 μm, which indicates that the optical lens can correct the chromatic aberration of the edge of the field of view and the secondary spectrum of the whole image surface very well.

[0145] Referring to Table 6, the optical properties corresponding to the above-mentioned embodiments are shown, including the effective focal length f, the maximum half field angle θ, the entrance pupil diameter EPD, the total optical length TTL, the aperture value FNO, the real image height IH, and the numerical value corresponding to each conditional expression in the embodiments.

[0146] Table 6

[0147]

[0148]

[0149] In summary, the optical lens provided by the embodiments of the present application realizes the effects of large field of view, large aperture and miniaturization by reasonably matching the lens shape and power combination between each lens.

[0150] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like 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.

[0151] The above 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 within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical lens, in total seven pieces of lenses, characterized in that, In order from the object side to the imaging surface along the optical axis are: 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 concave 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, and the image side surface of which is a convex surface; a fourth lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fifth lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a concave surface; a sixth lens with positive refractive power, the object side surface of which is a convex surface; a seventh lens with negative refractive power, the object side surface of which is a convex surface at the near optical axis, and the image side surface of which is a concave surface at the near optical axis; wherein the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 3.0 < IH / EPD < 3.5; the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.2 < TTL / f < 6.

8.

2. The optical lens of claim 1, wherein, the maximum field angle FOV of the optical lens and the aperture value FNO of the optical lens satisfy: 85° < FOV / FNO ≤ 87.

5.

3. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 3.2 < TTL / IH < 3.

5.

4. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 2.3 < f2 / f < 8.

0.

5. The optical lens of claim 1, wherein, the effective aperture D1 of the object side surface of the first lens, the real image height IH corresponding to the maximum field angle of the optical lens, and the maximum half field angle θ of the optical lens satisfy: 0.4 < D1 / IH / tan(θ) < 0.

6.

6. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the sum of the central thickness CT4 of the fourth lens, the central thickness CT5 of the fifth lens, and the central thickness CT6 of the sixth lens satisfy: 0.1 < (CT4+CT5+CT6) / TTL < 0.

3.

7. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the curvature radius R1 of the object side surface of the first lens satisfy: -36.48 ≤ R1 / f < -15.

0.

8. The optical lens of claim 1, wherein, the optical back focal length BFL of the optical lens and the total optical length TTL of the optical lens satisfy: 0.05 < BFL / TTL < 0.

12.

9. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the effective focal length f1 of the first lens satisfy: -2.0 < f1 / f < -1.

0.

10. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the effective focal length f3 of the third lens satisfy: 2.0 < f3 / f < 3.0.

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