Optical lens

Abstract

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

Description

TECHNICAL FIELD

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

[0002] With the continuous improvement of people's requirements for driving experience, vehicle application type optical lenses are used more and more in intelligent driving, and the position of vehicle optical lenses in the automobile industry is continuously improved.

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

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

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

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

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

[0008] The second lens with negative focal power;

[0009] The third lens with positive focal power, the image side surface is convex;

[0010] The fourth lens with positive focal power, the object side surface is convex;

[0011] The fifth lens with negative focal power, the image side surface is concave;

[0012] The sixth lens with positive focal power, the object side surface is concave, and the image side surface is convex.

[0013] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2 < TTL / f < 2.4.

[0014] Further preferably, the effective focal length f of the optical lens, the maximum field of view angle FOV of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.95 < (IH / 2) / (f x tan(FOV / 2)) < 1.05.

[0015] Further preferably, a real image height IH corresponding to a maximum field angle of the optical lens and an effective focal length f of the optical lens satisfy: 0.6 < IH / f < 0.7.

[0016] Further preferably, an optical total length TTL of the optical lens, a maximum field angle FOV of the optical lens and a real image height IH corresponding to the maximum field angle of the optical lens satisfy: 69 < 180° x TTL / (IH / 2) / (FOV / 2) < 73.

[0017] Further preferably, a curvature radius R1 of an object side surface of the first lens and a curvature radius R2 of an image side surface of the first lens satisfy: (R1+R2) / (R1-R2) <-7.

[0018] Further preferably, a curvature radius R11 of an object side surface of the sixth lens and a curvature radius R12 of an image side surface of the sixth lens satisfy: (R11+R12) / (R11-R12) > 1.05.

[0019] Further preferably, a curvature radius R6 of an image side surface of the third lens and a curvature radius R7 of an object side surface of the fourth lens satisfy: |(R6-R7) / (R6+R7)| > 4.5.

[0020] Further preferably, an effective focal length f of the optical lens and a focal length f1 of the first lens satisfy: f1 / f > 3.

[0021] Further preferably, an effective focal length f of the optical lens and a focal length f2 of the second lens satisfy: f2 / f <-1.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[0044] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0045] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0046] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0047] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0048] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0049] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0050] 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.

[0051] It should be noted that the embodiments and features of the embodiments in the present application 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.

[0052] The optical lens provided by the embodiment of the present application comprises six lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface as the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens.

[0053] In some embodiments, the first lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface. The second lens can have a negative focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which can be a concave surface or a convex surface. The third lens can have a positive focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which is a convex surface. The fourth lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which can be a concave surface or a convex surface. The fifth lens can have a negative focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which is a concave surface. The sixth lens can have a positive focal power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface.

[0054] In some embodiments, the optical lens can further comprise a diaphragm, which can be located between the first lens and the second lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging. When the diaphragm is located between the first lens and the second lens, the correction of the diaphragm aberration is facilitated.

[0055] In some embodiments, the optical lens can further comprise a filter, which can be arranged between the sixth lens and the imaging surface. The filter is used to filter out the interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting the normal imaging.

[0056] In some embodiments, the fourth lens and the fifth lens can be bonded to form a bonded lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; and can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens.

[0057] In some embodiments, the optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2 < TTL / f < 2.4. Satisfying the above range is beneficial to limit the total length of the lens and achieve miniaturization.

[0058] In some embodiments, the effective focal length f of the optical lens, the maximum field of view FOV of the optical lens, and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 0.95 < (IH / 2) / (f*tan(FOV / 2)) < 1.05. Satisfying the above range can control the optical lens to have small distortion and improve the imaging quality of the optical lens.

[0059] In some embodiments, the real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 0.6 < IH / f < 0.7. Satisfying the above range controls the image height and focal length of the optical lens to be within a reasonable range, which helps the optical lens to have a large image surface and improve the imaging quality.

[0060] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.2 < BFL / f < 0.3. Satisfying the above range limits the optical lens to have a suitable back focus, which facilitates reasonable arrangement of the positions of the lenses and reduces the difficulty of processing and assembly.

[0061] In some embodiments, the optical total length TTL of the optical lens, the maximum field of view FOV of the optical lens, and the real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 69 < 180°*TTL / (IH / 2) / (FOV / 2) < 73. Satisfying the above range limits the length of the optical lens under the same imaging area and the same field of view, and achieves miniaturization of the optical lens.

[0062] In some embodiments, the optical total length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis satisfy: 0.6 < ∑CT / TTL < 0.8. Satisfying the above range reasonably configures the optical total length of the optical lens and the sum of the thicknesses of the lenses, which helps to achieve high-pixel characteristics and improve the imaging quality of the optical lens.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: f1 / f > 3. Satisfying the above range makes the first lens have positive refractive power and has the effect of converging light rays, which can reduce the front aperture.

[0064] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: f2 / f <-1. Satisfying the above range makes the second lens have negative optical power, has the effect of diverging light rays, further diverges the light rays exiting the first lens image side under the same field of view, disperses the central light rays and the edge light rays of each field of view, can make the rear optical system have a larger light receiving surface to receive the light rays exiting the second lens image side, realizes a larger light amount, and is beneficial to increasing the relative illumination.

[0065] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 0.8<f3 / f<1.2. Satisfying the above range limits the third lens to have appropriate positive optical power, has the effect of converging light rays, and cooperates with the negative optical power of the second lens to further converge the light rays passing through the second lens, lowers the height of the peripheral light rays, and is beneficial to reducing the aperture of the rear lens.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.8<f4 / f<1.3. Satisfying the above range limits the fourth lens to have appropriate positive optical power, is beneficial to converging light rays, and cooperates with the fifth lens having negative optical power to adjust the optical path difference between different fields of view, improve resolution, is beneficial to making the light rays enter the rear lens gently, and can further reduce field curvature and correct the off-axis point aberration of the optical lens.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: f5 / f <-0.4. Satisfying the above range limits the fifth lens to have negative optical power, can diverge the light rays exiting the fourth lens, makes the light rays of the edge field of view have an upward trend, is beneficial to making the image points on the imaging surface away from the optical axis, is beneficial to realizing the effect of matching a large chip, obtains a larger picture, and can be cemented with the fourth lens having positive optical power, can effectively eliminate aberration, and improve the resolution of the optical lens.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: f6 / f>9.5. Satisfying the above range limits the sixth lens to have positive optical power, is beneficial to converging light rays, makes the light rays smoothly transition to the rear, reduces the height of the light rays incident to the rear, slows down the upward trend of the light rays, avoids the light energy loss caused by the large main light ray angle of the large field of view light rays reaching the imaging surface, is beneficial to improving the illumination of the edge field of view, and is beneficial to realizing a short total optical length.

[0069] In some embodiments, the effective focal length f of the optical lens and the image-side radius of curvature R10 of the fifth lens satisfy: 0.45 < R10 / f < 0.8. Satisfying the above range, the incidence angle of peripheral light to the object-side surface of the sixth lens can be increased, which is beneficial to improve the relative illumination of the peripheral field of view.

[0070] In some embodiments, the image-side radius of curvature R6 of the third lens and the object-side radius of curvature R7 of the fourth lens satisfy: |(R6-R7) / (R6+R7)| > 4.5. Satisfying the above range, the image-side surface of the third lens and the object-side surface of the fourth lens are approximately symmetric structures, which can converge light, reduce the aperture of the rear lens, and smoothly transfer the light collected by the front lens to the rear lens.

[0071] In some embodiments, the object-side radius of curvature R1 of the first lens and the image-side radius of curvature R2 of the first lens satisfy: (R1+R2) / (R1-R2) <-7. Satisfying the above range, the light can be converged, as many large field of view light as possible is collected into the rear lens, the light quantity is increased, the large angle light passing through the image-side surface of the first lens is rapidly diverged, the subsequent lens has a larger light receiving surface, which is beneficial to the correction of large angle light aberration of the rear lens, reduces distortion, and realizes high resolution.

[0072] In some embodiments, the object-side radius of curvature R11 of the sixth lens and the image-side radius of curvature R12 of the sixth lens satisfy: (R11+R12) / (R11-R12) > 1.05. The edge field of view light and the central light passing through the object-side surface of the sixth lens can be turned up, and the light passing through the image-side surface of the sixth lens has a gentle trend, which has the effect of increasing the back focus and reducing the CRA.

[0073] In some embodiments, the optical lens satisfies the following conditional expressions: 14mm < f < 16mm; 30° < FOV < 40°; 9mm < EPD < 10mm; 33mm < TTL < 36mm; 1.5 < Fno < 1.8; 9mm < IH < 10mm; 15° < CRA < 19°; 3mm < BFL < 4.5mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray incidence angle at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Satisfying the above range, the optical lens has one or more advantages such as large target surface, large aperture, long focal length, etc.

[0074] In some embodiments, the lens material in the optical lens provided by the present application can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the low dispersion characteristic of the glass can effectively correct the geometric chromatic aberration of the optical system. The optical lens provided by the present application can adopt a full-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0075] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens can adopt a spherical lens or an aspherical lens. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving the miniaturization of the lens. More specifically, the first lens, the second lens, the fourth lens, and the fifth lens of the present application adopt a spherical lens, and the third lens and the sixth lens adopt an aspherical lens.

[0076] In various embodiments of the present application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[0077] ;

[0078] wherein z is the distance of the curved surface from the vertex of the curved surface in the direction of the optical axis, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic surface coefficient, and B, C, D, E, and F are the fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients, respectively.

[0079] The present application will be further described in the following embodiments. In various embodiments, 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 present application, but the embodiments of the present 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 present application should be regarded as equivalent replacement modes, and are included in the protection scope of the present application.

[0080] Embodiment 1

[0081] Please refer to Figure 1 , which is a structure schematic diagram of the optical lens provided in the embodiment 1 of the present application. The optical lens sequentially includes a first lens L1, a stop ST, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter G1 along the optical axis from the object side to the imaging surface.

[0082] Among them, the first lens L1 has a positive focal power, the object side surface S1 is a convex surface, and the image side surface S2 is a concave surface.

[0083] The second lens L2 has negative focal power, the object side S3 is concave, and the image side S4 is convex;

[0084] The third lens L3 has positive focal power, the object side S5 and the image side S6 are both convex;

[0085] The fourth lens L4 has positive focal power, the object side S7 and the image side S8 are both convex;

[0086] The fifth lens L5 has negative focal power, the object side S8 and the image side S9 are both concave;

[0087] The fourth lens L4 and the fifth lens L5 form a cemented lens group, that is, the cemented surface S8 of the image side of the fourth lens L4 and the object side of the fifth lens L5;

[0088] The sixth lens L6 has positive focal power, the object side S10 is concave, and the image side S11 is convex;

[0089] The object side S12 and the image side S13 of the filter G1 are both flat;

[0090] The imaging surface S14 is flat.

[0091] The third lens L3 and the sixth lens L6 are glass aspherical lenses, and the first lens L1, the second lens L2, the fourth lens L4 and the fifth lens L5 are glass spherical lenses.

[0092] The related parameters of the lenses in the optical lens in Embodiment 1 are shown in Table 1-1.

[0093] Table 1-1

[0094]

[0095] The surface type parameters of the aspherical lenses of the optical lens in Embodiment 1 are shown in Table 1-2.

[0096] Table 1-2

[0097]

[0098] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are shown in Figure 2 、 Figure 3 、 Figure 4 respectively.

[0099] Figure 2The field curvature curve of the 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 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 ±0.06 mm, which shows that the optical lens can well correct the field curvature.

[0100] Figure 3 The F-Tan(Theta) distortion curve of the embodiment 1 is shown, which represents the distortion of light rays of different wavelengths at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the distortion of the optical lens is controlled within ±1%, which shows that the optical lens can well correct the distortion.

[0101] Figure 4 The MTF (Modulation Transfer Function) curve of the 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 in the full field of view, and in the range of 0-120 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0102] Embodiment 2

[0103] Please refer to Figure 5 , which is a structural schematic diagram of the optical lens provided in the embodiment 2 of the present application, and the main difference between the embodiment and the embodiment 1 is that the object side S5 of the third lens L3 is a concave surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0104] The related parameters of each lens in the optical lens in the embodiment 2 are shown in Table 2-1.

[0105] Table 2-1

[0106]

[0107] The surface type parameters of the aspherical lens of the optical lens in the embodiment 2 are shown in Table 2-2.

[0108] Table 2-2

[0109]

[0110] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are respectively as shown in Figure 6 、 Figure 7 、 Figure 8as shown.

[0111] From Figure 6 it can be seen that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.05mm, which shows that the optical lens can well correct the field curvature.

[0112] From Figure 7 it can be seen that the distortion of the optical lens is controlled within ±2%, which shows that the optical lens can well correct the distortion.

[0113] From Figure 8 it can be seen that the MTF value of the optical lens in the embodiment is above 0.38 in the full field of view, and in the range of 0-120lp / mm, the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0114] Embodiment 3

[0115] Referring to Figure 9 , a structure schematic diagram of the optical lens provided in the embodiment 3 of the present application is shown, and compared with the embodiment 1, the main difference is that the fourth lens L4 and the fifth lens L5 are not cemented lens groups; the image side surface S8 of the fourth lens L4 is a concave surface; the object side surface S9 of the fifth lens L5 is a convex surface; the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0116] The related parameters of each lens in the optical lens in the embodiment 3 are shown in Table 3-1.

[0117] Table 3-1

[0118]

[0119] The surface type parameters of the aspheric lens of the optical lens in the embodiment 3 are shown in Table 3-2.

[0120] Table 3-2

[0121]

[0122] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are respectively shown in Figure 10 , Figure 11 , Figure 12 .

[0123] From Figure 10 it can be seen that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.05mm, which shows that the optical lens can well correct the field curvature.

[0124] From Figure 11It can be seen from the figure that the distortion of the optical lens is controlled within ±3%, which indicates that the optical lens can well correct the distortion.

[0125] From Figure 12 It can be seen from the figure that the MTF value of the optical lens is above 0.25 in the full field of view, and the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view in the range of 0-120 lp / mm, and the imaging quality and the detail resolution capability are good in the low-frequency and high-frequency cases.

[0126] Embodiment 4

[0127] Please refer to Figure 13 , which is a structural schematic diagram of the optical lens provided in Embodiment 4 of the present application. Compared with Embodiment 1, the main difference is that the fourth lens L4 and the fifth lens L5 are not cemented lens groups; the image side surface S8 of the fourth lens L4 is a concave surface; the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0128] The related parameters of each lens in the optical lens in Embodiment 4 are shown in Table 4-1.

[0129] Table 4-1

[0130]

[0131] The surface type parameters of the aspherical lens of the optical lens in Embodiment 4 are shown in Table 4-2.

[0132] Table 4-2

[0133]

[0134] In this embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are shown in Figure 14 , Figure 15 , Figure 16 respectively.

[0135] From Figure 14 It can be seen that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.05 mm, which indicates that the optical lens can well correct the field curvature.

[0136] From Figure 15 It can be seen that the distortion of the optical lens is controlled within ±2%, which indicates that the optical lens can well correct the distortion.

[0137] From Figure 16It can be seen from the figure that the MTF value of the optical lens in the embodiment is above 0.4 in the full field of view, and in the range of 0-120 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and the imaging quality and the detail resolution capability are good in the low frequency and high frequency cases.

[0138] Embodiment 5

[0139] Please refer to Figure 17 , which is a structural schematic diagram of the optical lens provided in Embodiment 5 of the present application. Compared with Embodiment 1, the main difference is that the object side S3 of the second lens L2 is a convex surface, the image side S4 of the second lens L2 is a concave surface, and the optical parameters such as the curvature radius and the lens thickness of each lens surface are different.

[0140] The related parameters of each lens in the optical lens in Embodiment 5 are shown in Table 5-1.

[0141] Table 5-1

[0142]

[0143] The surface type parameters of the aspherical lens of the optical lens in Embodiment 5 are shown in Table 5-2.

[0144] Table 5-2

[0145]

[0146] In the embodiment, the field curvature curve, the F-Tan(Theta) distortion curve and the MTF curve of the optical lens are shown in Figure 18 , Figure 19 , Figure 20 respectively.

[0147] It can be seen from Figure 18 that the field curvature of the meridional image surface and the sagittal image surface is controlled within ±0.1 mm, which indicates that the optical lens can well correct the field curvature.

[0148] It can be seen from Figure 19 that the distortion of the optical lens is controlled within ±2%, which indicates that the optical lens can well correct the distortion.

[0149] It can be seen from Figure 20 that the MTF value of the optical lens in the embodiment is above 0.2 in the full field of view, and in the range of 0-120 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and the imaging quality and the detail resolution capability are good in the low frequency and high frequency cases.

[0150] Please refer to Table 6 for the optical characteristics of the above-mentioned embodiments, including the effective focal length f, the total track length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the chief ray angle of incidence CRA at the maximum image height, the maximum field of view angle FOV of the optical lens, and the numerical value corresponding to each conditional expression in the embodiments.

[0151] Table 6

[0152]

[0153] In summary of the above embodiments, the optical lens provided by the present application adopts six lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as large target surface, large aperture, high imaging quality, etc.

[0154] 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.

[0155] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the scope of protection 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, six pieces of lenses in total, characterized in that, In order from the object side to the imaging plane along the optical axis, the optical lens comprises in sequence: a first lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens with negative refractive power; a third lens with positive refractive power, 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; a fifth lens with negative refractive power, 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 concave surface, and the image side surface of which is a convex surface; a seventh lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a radius of curvature R1 of the object side surface of the first lens and a radius of curvature R2 of the image side surface of the first lens satisfy: -22.17≤(R1+R2) / (R1-R2)<-7; an effective focal length f of the optical lens and a focal length f1 of the first lens satisfy: 8≥f1 / f>3; the effective focal length f of the optical lens and a focal length f2 of the second lens satisfy: -2.22≤f2 / f<-1; the effective focal length f of the optical lens satisfies: 14mm<f<16mm; 2. The optical lens of claim 1, wherein, the effective focal length f of the optical lens, a maximum field of view FOV of the optical lens, and a real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 0.95<(IH / 2) / (f×tan(FOV / 2))<1.

05.

3. The optical lens of claim 1, wherein, an optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 2.2<TTL / f<2.

4.

4. The optical lens of claim 1, wherein, a real image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 0.6<IH / f<0.

7.

5. The optical lens of claim 1, wherein, an optical total length TTL of the optical lens, a maximum field of view FOV of the optical lens, and a real image height IH corresponding to the maximum field of view FOV of the optical lens satisfy: 69<180°×TTL / (IH / 2) / (FOV / 2)<73.

6. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and a focal length f4 of the fourth lens satisfy: 0.8<f4 / f<1.

3.

7. The optical lens of claim 1, wherein, a radius of curvature R11 of the object side surface of the sixth lens and a radius of curvature R12 of the image side surface of the sixth lens satisfy: 13.06≥(R11+R12) / (R11-R12)>1.

05.

8. The optical lens of claim 1, wherein, a radius of curvature R6 of the image side surface of the third lens and a radius of curvature R7 of the object side surface of the fourth lens satisfy: 87.63≥|(R6-R7) / (R6+R7)|>4.

5.

9. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and a radius of curvature R10 of the image side surface of the fifth lens satisfy: 0.45<R10 / f<0.

8. the effective focal length f of the optical lens and a back focal length BFL of the optical lens satisfy: 0.2<BFL / f<0.3.

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