Optical lens

Abstract

The invention provides an optical lens, which comprises six lenses which sequentially comprise a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with positive focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the second lens has positive focal power, the object side surface of the second lens is a convex surface near the optical axis, and the image side surface of the second lens is a concave surface near the optical axis; the object side surface and the image side surface of the third lens are convex surfaces; the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; the fifth lens has negative focal power, the object side surface of the fifth lens is a convex surface near the optical axis, and the image side surface of the fifth lens is a concave surface near the optical axis; the sixth lens has negative focal power, the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface near the optical axis; the focal length f5 of the fifth lens and the effective focal length f of the optical lens meet the following formula:-25lt; f5 / flt; -3. According to the optical lens provided by the invention, 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.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging lenses, and in particular to an optical lens. Background Art

[0002] With the continuous upgrading of smartphones, consumers have higher and higher requirements for the shooting functions of mobile phones. The 35mm focal length (i.e., a full field of view of 63°) is considered a classic focal length for humanistic photography. Compared with the 24mm focal length, it is easier to highlight the subject; compared with the 50mm focal length, it has a larger shooting angle and is applicable to a wider range of scenarios. The 35mm focal length lens, with its relatively large viewing angle, can provide photographers with a rich ability to capture scenes, especially suitable for shooting full-body portraits; when shooting portraits, the subject can be naturally integrated into the surrounding environment, showing a more vivid and story-rich picture.

[0003] However, there are very few mobile phones on the market equipped with a main camera lens with a full field of view of 63°. Part of the reason is that the aperture of the lens at this focal length is more difficult to increase than that of the lens at the 24mm focal length, and the image height is also more difficult to increase, making it difficult to meet the usage needs of consumers. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide an optical lens having the advantage of excellent imaging quality.

[0005] The technical solution adopted by the present invention is:

[0006] An optical lens, comprising six lenses, which include:

[0007] The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave;

[0008] The second lens has positive refractive power, the object side surface of which is convex at the near optical axis, and the image side surface of which is concave at the near optical axis;

[0009] The third lens has positive refractive power, and both the object side surface and the image side surface are convex;

[0010] a fourth lens having negative optical power, whose object side surface is concave and whose image side surface is convex;

[0011] A fifth lens having negative optical power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis;

[0012] a sixth lens element having negative optical power, whose object side surface is concave and whose image side surface is concave near the optical axis;

[0013] The focal length f5 of the fifth lens satisfies the effective focal length f of the optical lens: -25 <f5 / f<-3。

[0014] More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.15 < TTL / f < 1.25; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.9 < TTL / IH < 0.95; the effective focal length f, the maximum field of view angle FOV, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1 < (IH / 2) / (f × tan(FOV / 2)) < 1.02.

[0015] More preferably, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 2 < f1 / f < 2.4; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1.

[0016] More preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 30 < f2 / f < 56; the radius of curvature R3 of the object side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R3 / f < 0.4; the radius of curvature R4 of the image side surface of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R4 / f < 0.4.

[0017] More preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f3 / f < 1; the radius of curvature R5 of the object side surface of the third lens and the effective focal length f of the optical lens satisfy: 0.6 < R5 / f < 0.8; the radius of curvature R6 of the image side surface of the third lens and the effective focal length f of the optical lens satisfy: -2 < R6 / f < -0.8.

[0018] More preferably, the combined focal length f23 of the second lens and the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f23 / f < 1.1; the combined focal length f23 of the second lens and the third lens and the focal length f4 of the fourth lens satisfy: -0.2 < f23 / f4 < -0.05.

[0019] More preferably, the focal length f4 of the fourth lens and the focal length f5 of the fifth lens satisfy: 0.3 < f4 / f5 < 1.5; the radius of curvature R8 of the image side surface of the fourth lens and the radius of curvature R9 of the object side surface of the fifth lens satisfy: -8.1 < (R8 - R9) / (R8 + R9) < -2.8; the radius of curvature R8 of the image side surface of the fourth lens and the radius of curvature R9 of the object side surface of the fifth lens satisfy: -0.8 < R8 / R9 < -0.4.

[0020] More preferably, the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 1 < R9 / f < 1.8; the radius of curvature R10 of the image side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.7 < R10 / f < 1.3.

[0021] More preferably, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: -0.9 < R5 / R6 < -0.3; the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: 1.1 < R9 / R10 < 1.9.

[0022] More preferably, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens satisfy: -0.5 < (R5 + R6) / (R5 - R6) < 0; the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: 3.3 < (R9 + R10) / (R9 - R10) < 16.7.

[0023] Compared with the prior art, the optical lens provided by the present invention adopts six lenses with specific optical powers. Through specific surface shape settings and reasonable optical power distributions, the lens can simultaneously have the characteristics of long focal length, large image plane, and large aperture. The long focal length helps the photographer to have rich scene capture capabilities and show more vivid pictures. The large image plane helps to improve the resolution of the lens. The large aperture enables the lens to have excellent imaging quality even in dark environments at night. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 is the field curvature curve graph of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 is the F-Tan(Theta) distortion curve of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 is the vertical chromatic aberration curve graph of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5 is the relative illumination curve graph of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0031] Figure 7 4 is a field curvature curve diagram of the optical lens in Example 2 of the present invention.

[0032] Figure 8 : is the F-Tan (Theta) distortion curve of the optical lens in Example 2 of the present invention.

[0033] Fig. 9 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0034] Fig.10 This is a relative illumination curve diagram of the optical lens in Example 2 of the present invention.

[0035] Fig.11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0036] Fig.12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0037] Fig.13 : is the F-Tan (Theta) distortion curve of the optical lens in Example 3 of the present invention.

[0038] Fig.14 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0039] Fig.15 This is a relative illumination curve diagram of the optical lens in Example 3 of the present invention.

[0040] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0041] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application, and are not intended to limit the scope of the present 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.

[0042] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0043] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0044] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface 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 position of the concave surface 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 object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0045] It should also be understood that the terms "comprises", "including", "having", "includes" 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. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0046] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0047] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0048] The optical lens provided by the embodiment of the present invention comprises six lenses in total, which include, in sequence from the object side to the imaging surface along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens.

[0049] In some embodiments, the first lens may have a positive focal power, with its object side being convex and its image side being concave. The second lens may have a positive focal power, with its object side being convex near the optical axis and its image side being concave near the optical axis. The third lens may have a positive focal power, with both its object side and image side being convex. The fourth lens may have a negative focal power, with its object side being concave and its image side being convex. The fifth lens may have a negative focal power, with its object side being convex near the optical axis and its image side being concave near the optical axis. The sixth lens may have a negative focal power, with its object side being concave and its image side being concave near the optical axis.

[0050] In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the object side and the first lens. It can be understood that the diaphragm can be used to limit the amount of incident light to change the brightness of the imaging.

[0051] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the sixth lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0052] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -25 < f5 / f < -3. Meeting the above range and reasonably limiting the proportion of the focal length of the fifth lens helps the optical lens to have the characteristic of a large image surface. More specifically, -24.1 < f5 / f < -3.33.

[0053] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.15 < TTL / f < 1.25; the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.9 < TTL / IH < 0.95; the effective focal length f, the maximum field of view angle FOV, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1 < (IH / 2) / (f × tan(FOV / 2)) < 1.02. Meeting the above range is beneficial to shortening the overall length of the optical lens while taking into account good imaging quality, realizing the miniaturization of the optical lens, and meeting the requirements of miniaturization and large image surface in the mobile phone application scenario; better controlling the optical distortion of the optical lens makes the imaging of each field of view clearer and improves the resolution of the optical lens. More specifically, 1.17 < TTL / f < 1.21, 0.9 < TTL / IH < 0.93.

[0054] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 2 < f1 / f < 2.4; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1. Meeting the above ranges enables the first lens to have an appropriate positive optical power and the sixth lens to have an appropriate negative optical power, which can reasonably control the light path at the front and rear parts of the optical lens respectively, reduce the difficulty of aberration correction for the intermediate lens, and improve the imaging quality. More specifically, 2.02 < f1 / f < 2.33, -1.33 < f6 / f < -1.04.

[0055] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 30 < f2 / f < 56; the radius of curvature R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R3 / f < 0.4; the radius of curvature R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R4 / f < 0.4. Meeting the above ranges, by reasonably defining the proportion of the focal length of the second lens and the shapes of the object side and the image side of the second lens, it helps to control the light entering the optical lens through the front lens to have a reasonable degree of deflection and helps to correct the field curvature. More specifically, 30.44 < f2 / f < 55.13, 0.29 < R3 / f < 0.38, 0.28 < R4 / f < 0.35.

[0056] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f3 / f < 1; the radius of curvature R5 of the object side of the third lens and the effective focal length f of the optical lens satisfy: 0.6 < R5 / f < 0.8; the radius of curvature R6 of the image side of the third lens and the effective focal length f of the optical lens satisfy: -2 < R6 / f < -0.8. Meeting the above ranges, by reasonably defining the proportion of the focal length of the third lens and the shapes of the object side and the image side of the third lens, it helps to further correct the aberration. More specifically, 0.76 < f3 / f < 1, 0.66 < R5 / f < 0.74, -1.97 < R6 / f < -0.88.

[0057] In some embodiments, the combined focal length f23 of the second lens and the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f23 / f < 1.1; the combined focal length f23 of the second lens and the third lens and the focal length f4 of the fourth lens satisfy: -0.2 < f23 / f4 < -0.05. Meeting the above ranges, by making the optical power distribution of the second lens, the third lens and the fourth lens reasonable, it helps the optical lens to achieve the telephoto feature. More specifically, 0.78 < f23 / f < 1.01, -0.18 < f23 / f4 < -0.07.

[0058] In some embodiments, the focal length f4 of the fourth lens and the focal length f5 of the fifth lens satisfy: 0.3 < f4 / f5 < 1.5; the radius of curvature R8 of the image side of the fourth lens and the radius of curvature R9 of the object side of the fifth lens satisfy: -8.1 < (R8 - R9) / (R8 + R9) < -2.8; the radius of curvature R8 of the image side of the fourth lens and the radius of curvature R9 of the object side of the fifth lens satisfy: -0.8 < R8 / R9 < -0.4. Satisfying the above ranges, by reasonably defining the ratio of the focal lengths of the fourth lens and the fifth lens, and the shapes of the image side of the fourth lens and the object side of the fifth lens, it helps to control the trend of the marginal field beam to increase the image height, while reducing the off-axis aberration of the optical lens. More specifically, 0.32 < f4 / f5 < 1.41.

[0059] In some embodiments, the radius of curvature R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: 1 < R9 / f < 1.8; the radius of curvature R10 of the image side of the fifth lens and the effective focal length f of the optical lens satisfy: 0.7 < R10 / f < 1.3. Satisfying the above ranges, by reasonably defining the shapes of the object side and the image side of the fifth lens, it can converge the marginal field angle light rays and improve the relative illumination of the optical lens. More specifically, 1.04 < R9 / f < 1.72, 0.75 < R10 / f < 1.27.

[0060] In some embodiments, the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -0.9 < R5 / R6 < -0.3; the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 1.1 < R9 / R10 < 1.9. Satisfying the above ranges, by reasonably defining the shapes of the object side and the image side of the third lens, and the shapes of the object side and the image side of the fifth lens, it helps to optimize the aberration and improve the imaging quality. More specifically, -0.83 < R5 / R6 < -0.36, 1.12 < R9 / R10 < 1.84.

[0061] In some embodiments, the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -0.5 < (R5 + R6) / (R5 - R6) < 0; the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 3.3 < (R9 + R10) / (R9 - R10) < 16.7. Satisfying the above ranges, by reasonably defining the shapes of the object side and the image side of the third lens, and the shapes of the object side and the image side of the fifth lens, it helps to correct chromatic aberration, reduce the eccentricity sensitivity, balance the aberration, improve the imaging quality, and reduce the processing difficulty. More specifically, -0.47 < (R5 + R6) / (R5 - R6) < -0.09, 3.39 < (R9 + R10) / (R9 - R10) < 16.67.

[0062] In some embodiments, the maximum field of view (FOV) of the optical lens and the aperture value (Fno) of the optical lens satisfy: 35° < FOV / Fno < 36°; the true image height (IH) corresponding to the maximum field of view of the optical lens and the entrance pupil diameter (EPD) of the optical lens satisfy: 2.35 < IH / EPD < 2.45. Meeting the above ranges makes the aperture match the field of view angle, which is beneficial to expanding the field of view angle of the optical lens and increasing the aperture of the optical lens, facilitating the acquisition of more picture information to meet the requirements of large-range detection. The characteristic of a large aperture enables the optical lens to take pictures in a relatively dark environment, and at the same time helps to blur the background, making the main body more prominent; moreover, it can make the width of the light beam incident on the optical lens at different field of view angles reasonable, improve the brightness of the optical lens at the image plane, avoid vignetting, and at the same time increase the image height of the optical lens, facilitating the backend chip to obtain more picture information and reducing the information processing pressure of the backend chip. More specifically, 35.45° < FOV / Fno < 35.47°, 2.39 < IH / EPD < 2.42.

[0063] In some embodiments, the sum (∑CT) of the central thicknesses of the first lens to the sixth lens along the optical axis and the total optical length (TTL) of the optical lens satisfy: 0.6 < ∑CT / TTL < 0.75, and the sum (∑CT) of the central thicknesses of the first lens to the sixth lens along the optical axis and the effective focal length (f) of the optical lens satisfy: 0.75 < ∑CT / f < 0.9. Meeting the above ranges can achieve high-pixel characteristics, improve the imaging quality of the optical lens, and is beneficial to meeting the processability of each lens and reducing production costs. More specifically, 0.65 < ∑CT / TTL < 0.71, 0.78 < ∑CT / f < 0.85.

[0064] In some embodiments, the clear aperture radius (d1) of the object side of the first lens, the true image height (IH) corresponding to the maximum field of view of the optical lens, and the maximum field of view (FOV) of the optical lens satisfy: 0.6 < d1 / (IH / 2) / tan(FOV / 2) < 0.7. Meeting the above range, by reasonably controlling the relationship between the front aperture of the optical lens, the true image height corresponding to the maximum field of view, and the maximum field of view angle, helps to meet the small-head requirement of the optical lens and improve the structural rationality of the optical lens. More specifically, 0.63 < d1 / (IH / 2) / tan(FOV / 2) < 0.66.

[0065] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: -13 < f4 / f < -5. Meeting the above range gives the fourth lens an appropriate negative optical power, which helps to reasonably balance the positive optical power of the front-end lens, avoid excessive light deflection caused by overly concentrated optical power, and reduce the difficulty of chromatic aberration correction for the optical lens. More specifically, -12.41 < f4 / f < -4.68.

[0066] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: 0 < f1 / f2 < 0.1; the radius of curvature R2 of the image side of the first lens and the radius of curvature R3 of the object side of the second lens satisfy: 1.3 < R2 / R3 < 1.7. Meeting the above range, by reasonably defining the ratio of the focal lengths of the first lens and the second lens, as well as the shapes of the image side of the first lens and the object side of the second lens, helps to correct various aberrations of the optical lens, improve the imaging quality of the optical lens, and enhance the picture clarity. More specifically, 0.03 < f1 / f2 < 0.08, 1.37 < R2 / R3 < 1.61.

[0067] In some embodiments, the sagittal height Sag9 of the clear aperture semi-diameter and the clear aperture semi-diameter d10 of the object side of the fifth lens satisfy: -0.3 < Sag9 / d9 < -0.05, and the sagittal height Sag10 / d10 of the clear aperture semi-diameter of the image side of the fifth lens satisfies: -0.2 < Sag10 / d10 < -0.1. Meeting the above range, by reasonably controlling the clear aperture semi-diameter and the corresponding sagittal height of the object side of the fifth lens, as well as the clear aperture semi-diameter and the corresponding sagittal height of the image side of the fifth lens, can effectively improve the imaging quality of the edge field of view and the imaging quality of the optical lens. More specifically, -0.27 < Sag9 / d9 < -0.05, -0.2 < Sag10 / d10 < -0.14.

[0068] In some embodiments, the optical lens satisfies the conditional formula: 13.2 mm < f < 13.4 mm, 65° < FOV < 66°, 7.1 mm < EPD < 7.3 mm, 15.8 mm < TTL < 16 mm, 1.8 < Fno < 1.9, 17 mm < IH < 17.5 mm, 35° < CRA < 38°, 1.7 mm < BFL < 2 mm; where 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 image height corresponding to the maximum field of view angle of the optical lens, CRA represents the chief ray angle of incidence at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of small volume, large image plane, large aperture, etc. More specifically, 13.25 mm < f < 13.36 mm, 65.5° < FOV < 65.7°, 7.16 mm < EPD < 7.23 mm, 15.81 mm < TTL < 15.99 mm, 1.84 < Fno < 1.86, 17.28 mm < IH < 17.32 mm, 35.91° < CRA < 37.21°, 1.79 mm < BFL < 1.98 mm.

[0069] In some embodiments, the lens material in the optical lens provided by the present invention may be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. On the other hand, when the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens in the optical lens provided by the present invention all adopt plastic lenses.

[0070] In some embodiments, the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens may adopt spherical lenses or aspherical lenses. 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 realizing the miniaturization of the lens. More specifically, the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens of the present invention can all adopt aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens.

[0071] In various embodiments of the present invention, when the lens adopts an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0072]

[0073] Among them, z is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height of h along the optical axis, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, B, C, D, E, F, G, H, I, and J are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order, eighteenth-order, and twentieth-order surface coefficients, respectively.

[0074] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0075] Example 1

[0076] See also Figure 1 , shown is a schematic diagram of the structure of the optical lens 100 provided in Example 1 of the present invention, and the optical lens 100 includes, along the optical axis from the object side to the imaging surface, an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a filter G1.

[0077] The first lens L1 has positive refractive power, its object side surface S1 is convex, and its image side surface S2 is concave;

[0078] The second lens L2 has positive refractive power, an object-side surface S3 thereof is convex at the near optical axis, and an image-side surface S4 thereof is concave at the near optical axis;

[0079] The third lens L3 has positive refractive power, and its object-side surface S5 and image-side surface S6 are convex;

[0080] The fourth lens L4 has negative refractive power, its object-side surface S7 is concave, and its image-side surface S8 is convex;

[0081] The fifth lens L5 has negative refractive power, an object-side surface S9 thereof is convex at the near optical axis, and an image-side surface S10 thereof is concave at the near optical axis;

[0082] The sixth lens L6 has negative refractive power, its object-side surface S11 is concave, and its image-side surface S12 is concave at the near optical axis;

[0083] The object side surface S13 and the image side surface S14 of the filter G1 are both planes;

[0084] The imaging surface S15 is a plane.

[0085] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 are all plastic aspherical lenses.

[0086] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0087] Table 1-1

[0088]

[0089]

[0090] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0091] Table 1-2

[0092] Face number K B C D E S1 -8.04E-01 6.51E-04 9.39E-05 -1.29E-05 2.94E-07 S2 -3.78E-01 -8.06E-03 1.27E-03 -8.91E-05 -2.79E-05 S3 -3.42E+00 -1.27E-02 1.34E-03 -1.77E-04 1.05E-05 S4 -4.18E+00 -7.54E-03 1.06E-03 -4.20E-04 9.33E-05 S5 1.43E+00 -4.02E-03 1.16E-03 -4.80E-04 9.64E-05 S6 9.21E+00 -3.01E-03 8.30E-04 -2.76E-04 5.42E-05 S7 -6.90E+00 -4.47E-03 3.91E-04 -5.89E-05 6.25E-06 S8 1.01E-01 -7.76E-04 2.29E-04 -2.14E-05 2.07E-06 S9 -9.90E+01 -3.42E-03 3.29E-05 -4.59E-06 6.67E-07 S10 -1.80E+01 -1.06E-03 -1.01E-04 1.06E-05 -6.17E-07 S11 4.81E+00 -3.84E-03 1.78E-04 -6.08E-06 6.06E-08 S12 -9.90E+01 -3.39E-03 1.12E-04 -3.57E-06 7.75E-08 Face number F G H I J S1 2.72E-07 -4.58E-08 3.40E-09 -1.22E-10 1.68E-12 S2 8.49E-06 -1.10E-06 7.60E-08 -2.73E-09 4.13E-11 S3 1.34E-06 -3.60E-07 3.45E-08 -1.54E-09 2.72E-11 S4 -9.49E-06 -1.78E-07 1.39E-07 -1.22E-08 3.57E-10 S5 -9.41E-06 -1.37E-07 1.23E-07 -1.07E-08 3.13E-10 S6 -5.13E-06 2.86E-08 3.59E-08 -2.75E-09 6.57E-11 S7 2.32E-07 -1.90E-07 2.18E-08 -9.26E-10 9.37E-12 S8 -1.38E-07 2.11E-09 3.74E-10 -2.36E-11 4.57E-13 S9 -6.97E-08 2.70E-09 4.43E-12 -4.21E-12 1.40E-13 S10 1.37E-08 1.60E-10 -9.46E-12 -1.76E-13 7.48E-15 S11 4.32E-09 -4.15E-11 -4.52E-12 -5.97E-14 4.68E-15 S12 -4.26E-10 -4.09E-12 -8.96E-14 2.61E-16 2.67E-17

[0093] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, vertical axis chromatic aberration curve, and axial aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 shown.

[0094] Figure 2 The field curvature curve of Example 1 is shown, which indicates the degree of curvature of light of different wavelengths on the meridional image plane and the sagittal image plane, with the horizontal axis indicating the offset (unit: mm) and the vertical axis indicating the half field angle (unit: °). It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within -0.2mm to 0.1mm, indicating that the optical lens can correct the field curvature well.

[0095] Figure 3 The F-Tan (Theta) distortion curve of Example 1 is shown, which represents the distortion of light of different wavelengths at different image heights on the imaging surface, with the horizontal axis representing the distortion value (unit: %) and the vertical axis representing the half field angle (unit: °). It can be seen from the figure that the distortion of the optical lens is controlled within 0-2%, indicating that the optical lens can correct the distortion well.

[0096] Figure 4 The vertical axis chromatic aberration curve of the optical lens 100 in this embodiment is shown, which represents the chromatic aberration of each wavelength relative to the central wavelength (0.555 μm) at different image heights on the imaging surface, the horizontal axis represents the vertical axis chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3 μm to 2 μm, indicating that the optical lens can correct chromatic aberration well.

[0097] Figure 5 The relative illumination curve of the optical lens 100 in this embodiment is shown, which represents the relative illumination values ​​at different viewing angles on the imaging plane, the horizontal axis represents the half viewing angle (unit: °), and the vertical axis represents the relative illumination. It can be seen from the figure that the relative illumination value of the optical lens 100 is still greater than 50% at the edge viewing angle, indicating that the optical lens 100 has an excellent relative illumination.

[0098] Example 2

[0099] See also Figure 6 , shown is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0100] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0101] Table 2-1

[0102]

[0103]

[0104] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0105] Table 2-2

[0106] Face number K B C D E S1 -9.13E-01 6.44E-04 9.80E-05 -1.29E-05 2.17E-07 S2 -1.21E+00 -8.68E-03 1.34E-03 -8.06E-05 -2.77E-05 S3 -1.33E+00 -1.18E-02 1.36E-03 -1.71E-04 1.06E-05 S4 -1.77E+00 -6.63E-03 1.16E-03 -4.19E-04 9.34E-05 S5 2.92E+00 -4.12E-03 1.15E-03 -4.66E-04 9.64E-05 S6 2.81E+01 -3.88E-03 7.57E-04 -2.75E-04 5.38E-05 S7 -1.45E+01 -4.72E-03 3.36E-04 -5.62E-05 6.06E-06 S8 3.01E+00 -1.69E-03 2.74E-04 -2.10E-05 1.97E-06 S9 -9.90E+01 -3.46E-03 5.96E-05 -1.04E-05 8.19E-07 S10 1.41E+00 -1.21E-03 -1.08E-04 1.07E-05 -6.15E-07 S11 6.46E+00 -3.40E-03 1.77E-04 -5.59E-06 6.38E-08 S12 -3.22E+01 -2.76E-03 1.04E-04 -3.75E-06 7.90E-08 Face number F G H I J S1 2.77E-07 -4.53E-08 3.37E-09 -1.26E-10 1.98E-12 S2 8.47E-06 -1.10E-06 7.62E-08 -2.71E-09 3.88E-11 S3 1.28E-06 -3.59E-07 3.48E-08 -1.59E-09 2.84E-11 S4 -9.50E-06 -1.82E-07 1.38E-07 -1.21E-08 3.58E-10 S5 -9.44E-06 -1.35E-07 1.23E-07 -1.07E-08 3.16E-10 S6 -5.05E-06 3.24E-08 3.54E-08 -2.79E-09 6.87E-11 S7 2.51E-07 -1.83E-07 2.17E-08 -1.03E-09 1.58E-11 S8 -1.48E-07 2.13E-09 4.08E-10 -2.23E-11 3.84E-13 S9 -6.19E-08 2.03E-09 -5.17E-11 -4.72E-12 3.74E-13 S10 1.38E-08 1.65E-10 -9.43E-12 -1.82E-13 7.39E-15 S11 4.07E-09 -4.62E-11 -4.40E-12 -5.60E-14 4.30E-15 S12 -4.14E-10 -5.33E-12 -6.10E-14 1.61E-15 -2.65E-19

[0107] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 200 are shown as follows: Figure 7 , Figure 8 , Fig. 9 , Fig.10 shown.

[0108] from Figure 7 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.2mm~0.1mm, indicating that the optical lens can correct the field curvature well.

[0109] from Figure 8 It can be seen that the distortion of the optical lens is controlled within 0-2%, indicating that the optical lens can correct the distortion well.

[0110] from Fig. 9 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -3μm ~ 2μm, indicating that the optical lens can correct chromatic aberration well.

[0111] from Fig.10 It can be seen that the relative illumination value of the optical lens is still greater than 50% at the edge of the field of view, indicating that the optical lens has excellent relative illumination.

[0112] Example 3

[0113] See also Fig.11 , shown is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, the main difference between this embodiment and Example 1 is that the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0114] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0115] Table 3-1

[0116]

[0117] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0118] Table 3-2

[0119]

[0120]

[0121] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 300 are shown in FIG. Fig.12 , Fig.13 , Fig.14 , Fig.15 shown.

[0122] from Fig.12 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within -0.2mm~0.1mm, indicating that the optical lens can correct the field curvature well.

[0123] from Fig.13 It can be seen that the distortion of the optical lens is controlled within -0.5% to 2%, indicating that the optical lens can correct the distortion well.

[0124] from Fig.14 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3μm, indicating that the optical lens can correct chromatic aberration well.

[0125] from Fig.15It can be seen that the relative illumination value of the optical lens is still greater than 50% at the edge of the field of view, indicating that the optical lens has excellent relative illumination.

[0126] Please refer to Table 4, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0127] Table 4

[0128]

[0129]

[0130] In summary of the above embodiments, the optical lens provided by the present invention can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens through a specific surface shape setting and reasonable optical power distribution, so that the optical lens has the advantages of telephoto, miniaturization, high pixels, and low distortion, which is in line with the development of increasingly miniaturized and high-performance mobile devices. The aperture value of the lens provided by the present invention can reach 1.85, which can match a 1 / 0.98" chip, and can effectively meet the design requirements of large aperture and large target surface.

[0131] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0132] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, comprising six lenses, characterized in that: It sequentially includes from the object side to the imaging plane along the optical axis: A first lens with positive optical power, whose object side is convex and whose image side is concave; A second lens with positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A third lens with positive optical power, whose object side and image side are both convex; A fourth lens with negative optical power, whose object side is concave and whose image side is convex; A fifth lens with negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; A sixth lens with negative optical power, whose object side is concave and whose image side is concave near the optical axis; Wherein, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -25 < f5 / f < -3.

2. The optical lens according to claim 1, characterized in that: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.15 < TTL / f < 1.25; the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.9 < TTL / IH < 0.95; the effective focal length f, the maximum field of view angle FOV, and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1 < (IH / 2) / (f×tan(FOV / 2)) < 1.

02.

3. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 2 < f1 / f < 2.4; the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1.

4. The optical lens according to claim 1, characterized in that: The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 30 < f2 / f < 56; the radius of curvature R3 of the object side of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R3 / f < 0.4; the radius of curvature R4 of the image side of the second lens and the effective focal length f of the optical lens satisfy: 0.25 < R4 / f < 0.

4.

5. The optical lens according to claim 1, characterized in that: The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f3 / f < 1; the radius of curvature R5 of the object side of the third lens and the effective focal length f of the optical lens satisfy: 0.6 < R5 / f < 0.8; the radius of curvature R6 of the image side of the third lens and the effective focal length f of the optical lens satisfy: -2 < R6 / f < -0.

8.

6. The optical lens according to claim 1, characterized in that: The combined focal length f23 of the second lens and the third lens and the effective focal length f of the optical lens satisfy: 0.7 < f23 / f < 1.1; the combined focal length f23 of the second lens and the third lens and the focal length f4 of the fourth lens satisfy: -0.2 < f23 / f4 < -0.

05.

7. The optical lens according to claim 1, characterized in that: The focal length f4 of the fourth lens and the focal length f5 of the fifth lens satisfy: 0.3 < f4 / f5 < 1.5; the radius of curvature R8 of the image side of the fourth lens and the radius of curvature R9 of the object side of the fifth lens satisfy: -8.1 < (R8 - R9) / (R8 + R9) < -2.8; the radius of curvature R8 of the image side of the fourth lens and the radius of curvature R9 of the object side of the fifth lens satisfy: -0.8 < R8 / R9 < -0.

4.

8. The optical lens according to claim 1, characterized in that: The radius of curvature R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: 1 < R9 / f < 1.8; the radius of curvature R10 of the image side of the fifth lens and the effective focal length f of the optical lens satisfy: 0.7 < R10 / f < 1.

3.

9. The optical lens according to claim 1, characterized in that: The radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -0.9 < R5 / R6 < -0.3; the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 1.1 < R9 / R10 < 1.

9.

10. The optical lens according to claim 1, characterized in that: The radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: -0.5 < (R5 + R6) / (R5 - R6) < 0; the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 3.3 < (R9 + R10) / (R9 - R10) < 16.7.

Images