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 first lens has a negative focal length, and an image side of the first lens is concave; the second lens has a positive focal length, and an image side of the second lens is convex; a stop is arranged between the first lens and the second lens; the third lens has a positive focal length, and an object side of the third lens is convex, and an image side of the third lens is convex; the fourth lens has a negative focal length; the fifth lens has a positive focal length; the sixth lens has a negative focal length; and the seventh lens has a positive focal length; wherein a real image height IH corresponding to a maximum field angle of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy 3.1<IH / EPD<4.2. Through reasonable collocation of lens shapes and focal length combinations between the lenses, the effect of large field of view, large aperture and miniaturization is achieved.

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. However, it 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 has the advantages of large aperture, large field of view and miniaturization.

[0004] To achieve the above-mentioned purpose, the present application provides an optical lens, which has a total of seven lenses, arranged in order along the optical axis from the object side to the imaging surface: a first lens with negative focal power, the image side of which is concave; a second lens with positive focal power, the image side of which is convex; a stop; a third lens with positive focal power, the object side of which is convex and the image side of which is convex; a fourth lens with negative focal power; a fifth lens with positive focal power; a sixth lens with negative focal power; and a seventh lens with positive focal power; 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: 3.1 < IH / EPD < 4.2.

[0005] In some embodiments, the object side of the first lens is convex.

[0006] In some embodiments, the object side of the first lens is concave.

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

[0008] In some embodiments, the object side of the second lens is concave.

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

[0010] In some embodiments, the object side of the fifth lens is convex and the image side is convex.

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

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

[0013] In some embodiments, the image side surface of the sixth lens is convex.

[0014] In some embodiments, the object side surface of the seventh lens is convex.

[0015] In some embodiments, the image side surface of the seventh lens is concave.

[0016] In some embodiments, the third lens and the seventh lens have aspheric surfaces.

[0017] In some embodiments, the second lens and the seventh lens have aspheric surfaces.

[0018] In some embodiments, the fourth lens and the fifth lens are cemented to form a cemented lens.

[0019] In some embodiments, the fourth lens, the fifth lens and the sixth lens are cemented to form a cemented lens.

[0020] In some embodiments, the maximum field of view FOV of the optical lens and the F-number FNO of the optical lens satisfy: 65° < FOV / FNO < 100°.

[0021] In some embodiments, the maximum field of view FOV of the optical lens and the chief ray angle of incidence CRA on the image plane of the maximum field of view of the optical lens satisfy: 3.0 < (FOV / 2) / CRA < 5.0.

[0022] In some embodiments, the total track length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.5 < TTL / f < 7.2.

[0023] 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: 0.3 < D1 / IH / tan(θ) < 0.6.

[0024] 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: 12 < |R1 / f|.

[0025] In some embodiments, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.0 < f1 / f < -1.0.

[0026] In some embodiments, the second lens image-side curvature radius R4 and the third lens object-side curvature radius R5 satisfy: -2.5 < R4 / R5 < 0.

[0027] In some embodiments, the effective focal length f of the optical lens and the effective focal length f2 of the second lens satisfy: 3.5 < f2 / f < 9.5.

[0028] In some embodiments, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.2 < f3 / f < 3.2.

[0029] In some embodiments, the effective focal length f of the optical lens and the effective focal length f6 of the sixth lens satisfy: -5.5 < f6 / f < -1.0.

[0030] In some embodiments, the optical back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.85.

[0031] In some embodiments, the optical total track 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.

[0032] Compared with the prior art, the optical lens provided by the present application has the advantages that: the optical lens has a compact large-aperture structure, and more light flux can enter the optical lens, so that the optical lens can also form a clear image in a dim environment, and the effects of large field of view, large aperture, and miniaturization are achieved. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 FIG. 1 is a structural schematic diagram of an optical lens according to an embodiment of the present application.

[0034] Figure 2 FIG. 3 is a field curvature curve diagram of the optical lens in the embodiment 1 of the present application.

[0035] Figure 3 FIG. 5 is a relative luminance curve diagram of the optical lens in the embodiment 1 of the present application.

[0036] Figure 4 FIG. 7 is an MTF curve diagram of the optical lens in the embodiment 1 of the present application.

[0037] Figure 5 FIG. 9 is an axial aberration curve diagram of the optical lens in the embodiment 1 of the present application.

[0038] Figure 6 The vertical axis chromatic aberration curve of the optical lens in the embodiment 1 of the present application.

[0039] Figure 7 The structural schematic diagram of the optical lens in the embodiment 2 of the present application.

[0040] Figure 8 The field curvature curve of the optical lens in the embodiment 2 of the present application.

[0041] Figure 9 The relative luminance curve of the optical lens in the embodiment 2 of the present application.

[0042] Figure 10 The MTF curve of the optical lens in the embodiment 2 of the present application.

[0043] Figure 11 The axial aberration curve of the optical lens in the embodiment 2 of the present application.

[0044] Figure 12 The vertical axis chromatic aberration curve of the optical lens in the embodiment 2 of the present application.

[0045] Figure 13 The structural schematic diagram of the optical lens in the embodiment 3 of the present application.

[0046] Figure 14 The field curvature curve of the optical lens in the embodiment 3 of the present application.

[0047] Figure 15 The relative luminance curve of the optical lens in the embodiment 3 of the present application.

[0048] Figure 16 The MTF curve of the optical lens in the embodiment 3 of the present application.

[0049] Figure 17 The axial aberration curve of the optical lens in the embodiment 3 of the present application.

[0050] Figure 18 The vertical axis chromatic aberration curve of the optical lens in the embodiment 3 of the present application.

[0051] Figure 19 The structural schematic diagram of the optical lens in the embodiment 4 of the present application.

[0052] Figure 20 The field curvature curve of the optical lens in the embodiment 4 of the present application.

[0053] Figure 21 The relative luminance curve of the optical lens in the embodiment 4 of the present application.

[0054] Figure 22 The MTF curve of the optical lens in the embodiment 4 of the present application.

[0055] Figure 23 A graph of an axial aberration curve of the optical lens in Embodiment 4 of the present application.

[0056] Figure 24 A graph of a lateral chromatic aberration curve of the optical lens in Embodiment 4 of the present application.

[0057] Figure 25 A schematic structural view of the optical lens in Embodiment 5 of the present application.

[0058] Figure 26 A graph of a curvature of field curve of the optical lens in Embodiment 5 of the present application.

[0059] Figure 27 A graph of a relative illuminance curve of the optical lens in Embodiment 5 of the present application.

[0060] Figure 28 A graph of an MTF curve of the optical lens in Embodiment 5 of the present application.

[0061] Figure 29 A graph of an axial aberration curve of the optical lens in Embodiment 5 of the present application.

[0062] Figure 30 A graph of a lateral chromatic aberration curve of the optical lens in Embodiment 5 of the present application. DETAILED DESCRIPTION

[0063] 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.

[0064] It is to be noted that the expressions first, second, third, etc. in the present specification are used only to distinguish one feature from another feature, and do not indicate any limitation of 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.

[0065] In the drawings, the thickness, size, and shape of lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of a spherical surface or an aspherical surface shown in the drawings is shown by way of example. That is, the shape of a spherical surface or an aspherical surface is not limited to the shape of a spherical surface or an aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0066] In the present disclosure, 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 plane is referred to as the image side surface of the lens.

[0067] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", when used in this specification, specify the presence of 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 describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Furthermore, the word "exemplary" is intended to mean an example or an illustration.

[0068] 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 should also be understood that the terms 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.

[0069] 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 accompanying drawings and in conjunction with the embodiments.

[0070] The optical lens according to the embodiments of the present application comprises, in order from the object side to the image side: a first lens, a second lens, a diaphragm, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and a filter and a protective glass.

[0071] The first lens has a negative focal power, the object side surface is convex or concave, and the image side surface is concave; the second lens has a positive focal power, the object side surface is convex or concave, and the image side surface is convex; the third lens has a positive focal power, the object side surface is convex, and the image side surface is convex; the fourth lens has a negative focal power, the object side surface is convex, and the image side surface is concave; the fifth lens has a positive focal power, the object side surface is convex, and the image side surface is convex; the sixth lens has a negative focal power, the object side surface is concave, and the image side surface is convex or concave; and the seventh lens has a positive focal power, the object side surface is convex, and the image side surface is concave.

[0072] In some embodiments, a diaphragm can be arranged between the second lens and the third lens and near the object side of the third lens to condense the range of light exiting the front end of the optical lens and reduce the back aperture of the optical lens.

[0073] 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 to share the chromatic aberration correction of the optical lens, improve the resolution of the optical lens, and make the structure of the optical lens compact, which is conducive to the miniaturization of the optical lens.

[0074] In some embodiments, the FNO of the optical lens satisfies 1.60≤FNO. Satisfying the above range is conducive to realizing the large aperture characteristic, and the image can also be ensured to be clear in a weak light environment or at night.

[0075] In some embodiments, the maximum half field angle θ of the optical lens satisfies 60°<θ. Satisfying the above range is conducive to realizing the wide-angle characteristic, so that more scene information can be obtained to meet the demand for large-range detection.

[0076] In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD satisfy 3.1<IH / EPD<4.2. 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.

[0077] In some embodiments, the maximum field angle FOV of the optical lens and the FNO satisfy 65°<FOV / FNO<100°. Satisfying the above range is conducive to expanding the field angle of the optical lens and increasing the aperture of the optical lens, realizing the characteristics of wide angle and large aperture. The realization of the wide-angle characteristic is conducive to the optical lens to obtain more scene information to meet the demand for large-range detection, and the realization of the large-aperture characteristic is conducive to improving the problem of rapid decline of relative brightness at the edge field of view caused by the wide angle, so that more scene information can also be obtained.

[0078] In some embodiments, the maximum field angle FOV of the optical lens and the incident angle CRA of the chief ray at the image plane satisfy 3.0<(FOV / 2) / CRA<5.0. Satisfying the above range can make the incident light of different field angles of the optical lens enter the image sensor at a suitable angle, thereby improving the photosensitive performance of the image sensor and the imaging quality of the optical lens.

[0079] In some embodiments, the optical total track length TTL of the optical lens and the effective focal length f satisfy: 6.5 < TTL / f < 7.2. Satisfying the above range can effectively limit the length and volume of the optical lens, and realize miniaturization of the optical lens.

[0080] In some embodiments, the effective aperture D1 of the first lens object side, the real image height IH corresponding to the maximum field of view angle, and the maximum half field of view angle θ satisfy: 0.3 < D1 / IH / tan(θ) < 0.6. Satisfying the above range can help to reduce the front end aperture of the optical lens, realize miniaturization of the optical lens, and help the optical lens to have a large aperture, improve the light flux of the optical lens while reducing the loss of light in and out, so that the optical lens can also improve the response rate of the system while realizing high-definition imaging in low light or even dim environment.

[0081] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R1 of the first lens object side satisfy: 12 < |R1 / f|. Satisfying the above range can effectively control the curvature of the first lens object side, increase the field of view angle, and control the front end aperture of the optical lens.

[0082] 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 help to moderate the change of the incident light refraction angle, avoid too strong change of the refraction angle to produce too much aberration, and help more light to enter the rear optical system, increase the illumination, and improve the imaging quality of the optical lens.

[0083] In some embodiments, the radius of curvature R4 of the second lens image side and the radius of curvature R5 of the third lens object side satisfy: -2.5 < R4 / R5 < 0. Satisfying the above range can make the focusing position of the light reflected by the third lens object side located behind the imaging surface, effectively improve the design ghost of the optical lens, and improve the imaging quality of the optical lens.

[0084] In some embodiments, the effective focal length f of the optical lens and the effective focal length f2 of the second lens satisfy: 3.5 < f2 / f < 9.5. Satisfying the above range can make the second lens have appropriate positive refractive power, help the light to transition smoothly, and correct the aberration produced by the excessive deflection of the light by the first lens, and improve the imaging quality of the optical lens.

[0085] In some embodiments, the effective focal length f of the optical lens and the effective focal length f3 of the third lens satisfy: 2.2 < f3 / f < 3.2. Satisfying the above range can make the third lens have appropriate positive refractive power, make the angle between the normal lines of the object side and the image side and the incident light smaller, thereby suppressing the generation of high-order aberration, and improving the imaging quality of the optical lens.

[0086] In some embodiments, the effective focal length f of the optical lens and the effective focal length f6 of the sixth lens satisfy: -5.5 < f6 / f < -1.0. Satisfying the above range can increase the imaging area of the optical lens and improve the imaging quality of the optical lens.

[0087] In some embodiments, the optical back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.85. Satisfying the above range can make the optical lens have a longer optical back focal length, which is beneficial to the assembly of the optical lens.

[0088] In some embodiments, the optical total 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 optical lens compact, which is beneficial to the miniaturization of the optical lens, and can also make the light enter smoothly and improve the illumination of the optical lens.

[0089] In order to make the system have better optical performance, a plurality of aspherical lenses are used in the lens, and each aspherical surface shape of the optical lens satisfies the following equation:

[0090]

[0091] 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, A, B, C, D, E, and F are the second-order, fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order curved surface coefficients, respectively.

[0092] The application will be further described in the following embodiments. In each embodiment, the thickness, the radius of curvature, and 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 preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, and any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the application should be regarded as equivalent replacement methods, and are included in the protection scope of the application.

[0093] Embodiment 1

[0094] 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, in order from the object side to the imaging surface S18 along the optical axis, 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, a filter G1, and a protective glass G2.

[0095] In the optical lens in Embodiment 1, 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 convex 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 negative focal power, the object side S7 is a convex surface, and the image side is a concave surface; the fifth lens L5 has positive focal power, the object side is a convex surface, and the image side S9 is a convex 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 negative focal power, the object side S10 is a concave surface, and the image side S11 is a concave surface; the seventh lens L7 has positive 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 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0096] The related parameters of the lenses in the optical lens in Embodiment 1 are shown in Table 1-1.

[0097] Table 1-1

[0098]

[0099] The curve coefficients of the aspherical lenses in the optical lens in Embodiment 1 are shown in Table 1-2.

[0100] Table 1-2

[0101]

[0102]

[0103] Figure 2 The field curvature curve of Embodiment 1 is shown, which represents the bending 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 of view (unit: °). As can be seen from the figure, the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.03 mm, which shows that the optical lens can correct the field curvature very well.

[0104] Figure 3 The relative luminance curve of Embodiment 1 is shown, which represents the relative luminance value of different field angles on the imaging surface, the horizontal axis represents the half field of view (unit: °), and the vertical axis represents the relative luminance (unit: %). As can be seen from the figure, the relative luminance value of the optical lens is still greater than 70% at the maximum half field of view, which shows that the optical lens has very good relative luminance.

[0105] Figure 4A modulation transfer function (MTF) curve of the optical lens of Embodiment 1 is shown, which represents the imaging modulation degree of different spatial frequencies in each field of view, the horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents MTF value. As can be seen from the figure, the MTF value of the embodiment is above 0.4 in 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 capability in low and high frequency cases.

[0106] Figure 5 An axial aberration curve of Embodiment 1 is shown, which represents the aberration of the optical axis at the imaging surface at each wavelength, 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 shift of the axial aberration is controlled within ±8 μm, which shows that the optical lens can well correct the axial aberration.

[0107] Figure 6 A curve of the axial chromatic aberration of Embodiment 1 is shown, which represents the chromatic aberration at different image heights on the imaging surface at each wavelength relative to the central wavelength (0.55 μm), the horizontal axis represents the axial chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. As can be seen from the figure, the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2 μm, which shows that the optical lens can very well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image surface.

[0108] Embodiment 2

[0109] Please refer to Figure 7 , which is a structural schematic diagram of the optical lens provided in Embodiment 2 of the present application, which includes, 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.

[0110] 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 negative focal power, the object side S7 is a convex surface, and the image side is a concave surface; the fifth lens L5 has positive focal power, the object side is a convex surface, and the image side S9 is a convex 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 negative focal power, the object side S10 is a concave surface, and the image side S11 is a concave surface; the seventh lens L7 has positive 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 has a plane object side S14 and a plane image side S15; and the protective glass G2 has a plane object side S16 and a plane image side S17.

[0111] The related parameters of the lenses in the optical lens in Embodiment 2 are shown in Table 2-1.

[0112] Table 2-1

[0113]

[0114] The curve coefficients of the aspheric lenses of the optical lens in Embodiment 2 are shown in Table 2-2.

[0115] Table 2-2

[0116]

[0117]

[0118] Figure 8 to Figure 12 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 Embodiment 2 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 ±0.035 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 60% 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 0.4 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 the optical lens has good imaging quality and good detail resolution ability in the low frequency and high frequency cases; the shift of the axial aberration is controlled within ±8 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 ±2.5 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 entire image surface very well.

[0119] Embodiment 3

[0120] Referring to Figure 13 , a structural diagram of an optical lens provided in Embodiment 3 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 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.

[0121] The first lens L1 has negative focal power, the object side S1 is a convex 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 negative focal power, the object side S7 is a convex surface, and the image side is a concave surface; the fifth lens L5 has positive focal power, the object side is a convex surface, and the image side is a convex surface; the sixth lens L6 has negative focal power, the object side is a concave surface, and the image side S10 is a concave surface; the fourth lens L4, 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 positive focal power, the object side S11 is a convex surface, and the image side S12 is a concave surface; the filter G1 has a flat object side S13 and a flat image side S14; and the protective glass G2 has a flat object side S15 and a flat image side S16.

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

[0123] Table 3-1

[0124]

[0125]

[0126] The curve coefficients of the aspherical lenses of the optical lens in Embodiment 3 are shown in Table 3-2.

[0127] Table 3-2

[0128]

[0129] Figure 14 to Figure 18The 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 3 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 ±0.04 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 all above 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 ±10 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.

[0130] Embodiment 4

[0131] Referring to Figure 19 , a structure schematic diagram of an optical lens provided in embodiment 4 of the present application is shown, which 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.

[0132] 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 negative focal power, the object side S7 is a convex surface, and the image side is a concave surface; the fifth lens L5 has positive focal power, the object side is a convex surface, and the image side S9 is a convex 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 negative focal power, the object side S10 is a concave surface, and the image side S11 is a convex surface; the seventh lens L7 has positive 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.

[0133] The related parameters of the lenses in the optical lens of embodiment 4 are shown in Table 4-1.

[0134] Table 4-1

[0135]

[0136]

[0137] The curve coefficients of the aspherical lens of the optical lens in embodiment 4 are shown in table 4-2.

[0138] Table 4-2

[0139]

[0140] Figure 20 to Figure 24 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 4 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 ±0.02 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 65% 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 ±8 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 ±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.

[0141] Embodiment 5

[0142] Please refer to Figure 25 , which is a structural schematic diagram of the optical lens provided in embodiment 5 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.

[0143] The first lens L1 has negative focal power, the object side S1 is a convex 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 negative focal power, the object side S7 is a convex surface, and the image side is a concave surface; the fifth lens L5 has positive focal power, the object side is a convex surface, and the image side is a convex surface; the sixth lens L6 has negative focal power, the object side is a concave surface, and the image side S10 is a concave surface; the fourth lens L4, 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 positive focal power, the object side S11 is a convex surface, 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.

[0144] The related parameters of the lenses in the optical lens in Example 5 are shown in Table 5-1.

[0145] Table 5-1

[0146]

[0147] The surface coefficients of the aspheric lenses of the optical lens in Example 5 are shown in Table 5-2.

[0148] Table 5-2

[0149]

[0150] Figure 26 to Figure 30 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 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 ±0.02 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 65% 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 the optical lens has good imaging quality and good detail resolution ability in the low frequency and high frequency conditions; the shift of the axial aberration is controlled within ±12 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 ±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 entire image surface very well.

[0151] Please refer to Table 6 for the optical characteristics of the above-mentioned embodiments, including the effective focal length f, the maximum half field angle θ, the entrance pupil diameter EPD, the total track length TTL, the F-number FNO, the image height IH, and the numerical values corresponding to each conditional expression in the embodiments of the optical lens.

[0152] Table 6

[0153] Parameter and conditional expression Example 1 Example 2 Example 3 Example 4 Example 5 f (mm) 4.29 4.32 4.28 4.48 4.43 θ (°) 70.00 70.00 70.00 70.00 70.00 EPD (mm) 2.68 2.70 2.68 2.80 2.22 TTL (mm) 29.90 29.90 29.90 29.90 29.92 FNO 1.60 1.60 1.60 1.60 2.00 IH (mm) 8.80 8.84 8.94 8.80 8.92 CRA (°) 20.00 15.00 20.00 20.00 20.01 IH / EPD 3.28 3.27 3.34 3.14 4.02 FOV / FNO (°) 87.50 87.50 87.50 87.50 70.00 (FOV / 2) / CRA 3.50 4.67 3.50 3.50 3.50 TTL / f 6.97 6.92 6.98 6.67 6.75 D1 / IH / tan(θ) 0.46 0.49 0.49 0.50 0.42 |R1 / f| 14.92 13.62 308.29 15.18 462.06 f1 / f -1.39 -1.56 -1.43 -1.63 -1.51 R4 / R5 -2.18 -0.88 -0.43 -1.49 -0.25 f2 / f 6.36 5.52 4.23 3.83 9.04 f3 / f 2.50 2.58 3.03 2.46 3.04 f6 / f -2.19 -2.48 -1.25 -5.04 -1.26 BFL / f 0.59 0.59 0.80 0.57 0.56 (CT4+CT5+CT6) / TTL 0.19 0.19 0.21 0.14 0.28

[0154] In summary, the optical lens of 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.

[0155] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a 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.

[0156] The above-mentioned 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 scope of the patent 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, a number of modifications and improvements can be made, which are all 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 plane along the optical axis are: a first lens with negative refractive power, the image side surface of which is a concave surface; a second lens with positive refractive power, the image side surface of which is a convex surface; a stop; 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 negative refractive power, the object side surface of which is a convex surface and the image side surface of which is a concave surface; a fifth 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 sixth lens with negative refractive power, the object side surface of which is a concave surface; a seventh lens with positive refractive 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; and the fourth lens and the fifth lens are cemented to form a cemented lens; wherein the maximum field angle of the optical lens corresponds to a real image height IH, and the entrance pupil diameter EPD of the optical lens satisfies: 3.1 < IH / EPD < 4.2; the maximum field angle FOV of the optical lens and the aperture value FNO of the optical lens satisfy: 65° < FOV / FNO < 100°.

2. The optical lens of claim 1, wherein, the maximum field angle FOV of the optical lens and the incident angle CRA of the chief ray of the maximum field angle of the optical lens on the image plane satisfy: 3.0 < (FOV / 2) / CRA < 5.

0.

3. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 6.5 < TTL / f < 7.

2.

4. 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: 0.3 < D1 / IH / tan(θ) < 0.

6.

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

0.

6. The optical lens of claim 1, wherein, the curvature radius R4 of the image side surface of the second lens and the curvature radius R5 of the object side surface of the third lens satisfy: -2.5 < R4 / R5 < 0.

7. The optical lens of claim 1, wherein, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.2 < f3 / f < 3.

2.

8. The optical lens of claim 1, wherein, the optical back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: 0.5 < BFL / f < 0.

85.

9. 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.

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