Optical lens

Abstract

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power, and the object side surface of the sixth lens is a concave surface; and the object side surface of the seventh lens is a convex surface near the optical axis, and the image side surface of the seventh lens is a concave surface near the optical axis. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the lens has one or more advantages of miniaturization, large aperture, large image height, large field angle, high pixel, high imaging quality and the like.

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] Background: With the rapid development of the automotive industry, vehicle safety and intelligence are receiving increasing attention. As one of the key sensors in automotive intelligent driving systems, the importance of in-vehicle cameras has become increasingly prominent. Traditional vehicles primarily rely on the driver's visual observation to obtain road conditions. However, human drivers have limited vision and are easily affected by factors such as fatigue and distraction, which can lead to traffic accidents. The emergence of in-vehicle cameras provides vehicles with an additional means of visual perception, capable of capturing real-time image information of the vehicle's surroundings, assisting drivers in making more accurate decisions. From a technological perspective, early in-vehicle cameras were primarily used for simple reversing imaging, with low resolution, poor image quality, and relatively limited functionality. With advances in image sensor technology, the pixel count of in-vehicle cameras has continuously increased, from the initial hundreds of thousands to millions or even tens of millions today, providing clearer and more detailed images. Simultaneously, the camera's field of view has also gradually expanded, from a single rearview camera to multiple types such as forward, side, and surround view cameras, fully covering the vehicle's surroundings and providing more comprehensive visual data support for the vehicle's automated driving assistance system.

[0003] In addition to requiring the optical lens to have a thin and short appearance and have high pixels, high resolution and other characteristics, the existing automotive lenses are also required to be able to produce clear images under low illumination conditions. Therefore, it is necessary to develop an optical lens with good imaging effects. 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 in the present invention is:

[0006] An optical lens, comprising seven lenses, including the following elements in order from the object side to the imaging surface along the optical axis:

[0007] The first lens has a negative optical power, and its object-side surface is concave and its image-side surface is concave;

[0008] a second lens having negative optical power, whose object-side surface is concave and whose image-side surface is convex;

[0009] a third lens element having positive optical power, whose object-side surface is convex and whose image-side surface is concave;

[0010] a fourth lens element having positive refractive power, whose object-side surface is convex and whose image-side surface is convex;

[0011] a fifth lens element having positive refractive power, whose object-side surface and image-side surface are convex;

[0012] a sixth lens element having negative optical power and a concave object-side surface;

[0013] The seventh lens element has positive refractive power, its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis;

[0014] The real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens and the maximum field angle FOV of the optical lens satisfy the following conditions: 0.5<(IH / 2) / (f×tan(FOV / 2))<0.55.

[0015] Further preferably, the total optical length TTL of the optical lens and the aperture value Fno of the optical lens meet the following requirements: 15mm <TTL / Fno<17mm。

[0016] Further preferably, the real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy the following relationship: 1.8 <IH / f<1.9。

[0017] Further preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.2 <f3 / f<5.5。

[0018] Further preferably, a curvature radius R3 of the object side surface of the second lens and a curvature radius R4 of the image side surface of the second lens satisfy: -10<(R3+R4) / (R3-R4)<-7.5.

[0019] Further preferably, the focal length f2 of the second lens, the object side curvature radius R3 of the second lens and the image side curvature radius R4 of the second lens satisfy: 11 <f2 / (R3+R4)<19。

[0020] Further preferably, the semi-aperture CSD11 of the object side end of the first lens and the semi-aperture sag SAGX11 of the object side end of the first lens meet the following conditions: -75 <CSD11 / SAGX11<-50。

[0021] Further preferably, the real image height IH corresponding to the object side semi-aperture CSD11 of the first lens and the maximum field angle of the optical lens satisfies: 0.5 <CSD11 / IH<0.6。

[0022] Further preferably, the Abbe number Vd1 of the first lens and the Abbe number Vd2 of the second lens satisfy: 75 <Vd1+Vd2<90。

[0023] Further preferably, the image side clear semi-aperture CSD32 of the third lens and the object side clear semi-aperture CSD41 of the fourth lens satisfy: 1 <CSD32 / CSD41<1.2。

[0024] The optical lens provided by the present invention uses seven lenses with specific optical powers. Through the combination of specific surface shapes and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, so that the lens has one or more advantages such as miniaturization, large aperture, large image height, large field of view, high pixel count, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0026] Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0027] Figure 2 Graph showing the field curvature of the optical lens in Example 1 of the present invention.

[0028] Figure 3 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 1 of the present invention.

[0029] Figure 4 1 is an axial aberration curve diagram of the optical lens in Example 1 of the present invention.

[0030] Figure 5 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0031] Figure 6 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0032] Figure 7 Graph showing the field curvature of the optical lens in Example 2 of the present invention.

[0033] Figure 8 FIG. 4 is a graph showing the F-Tan (Theta) distortion curve of the optical lens in Example 2 of the present invention.

[0034] Figure 9 2 is an axial aberration curve diagram of the optical lens in Example 2 of the present invention.

[0035] Figure 10 Graph showing vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0036] Figure 11 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0037] Figure 12 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0038] Figure 13 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0039] Figure 14 4 is an axial aberration curve diagram of the optical lens in Example 3 of the present invention.

[0040] Figure 15 Graph showing vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0041] Illustration: The blue line segment in the figure indicates a wavelength of 0.436um; the green line segment indicates a wavelength of 0.486um; the red line segment indicates a wavelength of 0.546um; the yellow line segment indicates a wavelength of 0.588um; and the purple line segment indicates a wavelength of 0.656um.

[0042] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0043] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely descriptions of 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.

[0044] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of the present invention.

[0045] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0046] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, 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.

[0047] 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 preclude 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 list of 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.

[0048] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0049] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this 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.

[0050] The optical lens provided in an embodiment of the present invention comprises seven lenses, which are arranged in order 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, a sixth lens, and a seventh lens.

[0051] In some embodiments, the first lens may have negative optical power, with its object-side surface being concave and its image-side surface being concave. The second lens may have negative optical power, with its object-side surface being concave and its image-side surface being convex. The third lens may have positive optical power, with its object-side surface being convex and its image-side surface being concave. The fourth lens may have positive optical power, with its object-side surface being convex and its image-side surface being convex. The fifth lens may have positive optical power, with its object-side surface being convex and its image-side surface being convex. The sixth lens may have negative optical power, with its object-side surface being concave and its image-side surface being either concave or convex. The seventh lens may have positive optical power, with its object-side surface being convex at the near optical axis and its image-side surface being concave at the near optical axis.

[0052] In some embodiments, the true image height IH corresponding to the maximum field angle of view of the optical lens, the effective focal length f of the optical lens, and the maximum field angle of view FOV of the optical lens satisfy: 0.5 < (H / 2) / (f × tan(FOV / 2)) < 0.55. Satisfying the above conditional formula enables the optical lens to have a relatively large field angle of view while also achieving the characteristic of a large image height, which is beneficial for the optical lens to match a relatively large-sized photosensitive chip, avoid vignetting, and improve the relative illumination of the optical lens; at the same time, it can effectively increase the proportion of the edge field of view of the optical lens in the entire image plane, control the edge distortion of the optical lens, and improve the imaging quality of the optical lens.

[0053] In some embodiments, the overall optical length TTL of the optical lens and the f-number Fno of the optical lens satisfy: 15 mm < TTL / Fno < 17 mm. Satisfying the above conditional formula, by controlling the relationship between the overall length and the f-number of the optical lens, it is ensured that the optical lens can meet the requirements of large aperture and miniaturization design, enabling the optical lens to obtain sufficient light transmittance in a dim environment and meet the needs of high-quality and high-definition shooting.

[0054] In some embodiments, the true image height IH corresponding to the maximum field angle of view of the optical lens and the effective focal length f of the optical lens satisfy: 1.8 < IH / f < 1.9. Satisfying the above conditional formula can achieve the characteristic of a large image plane of the lens, match a larger-sized chip, and achieve high-pixel imaging of the lens.

[0055] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.2 < f3 / f < 5.5. Satisfying the above conditional formula, by setting the third lens with a positive optical power and defining the ratio of the focal length of the third lens to the effective focal length of the optical lens, it is beneficial to adjust the light path of the light from the first lens and the second lens, enabling the optical lens to have certain characteristics of a large field angle of view, low sensitivity, and miniaturization.

[0056] In some embodiments, the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface of the second lens satisfy: -10 < (R3 + R4) / (R3 - R4) < -7.5. Satisfying the above conditions enables the second lens to effectively correct the aberration of the edge field of view of the optical lens, suppress the generation of astigmatism, and reduce the angle of the chief ray of the peripheral viewing angle incident on the imaging plane of the optical lens, thereby improving the imaging quality of the optical lens.

[0057] In some embodiments, the focal length f2 of the second lens, the curvature radius R3 of the object side surface of the second lens, and the curvature radius R4 of the image side surface of the second lens satisfy: 11 < f2 / (R3 + R4) < 19. By satisfying the above conditional formula, the surface profiles of the object side surface and the image side surface of the second lens can be constrained, which is beneficial to reducing the bending degree of light rays at the image side surface of the second lens, reducing the astigmatism of the optical lens, so as to balance the astigmatism problem brought by the large field angle of the optical lens, and ensuring that the astigmatism of the optical lens is not too large while having a large field of view, thereby ensuring that the optical lens has excellent imaging quality.

[0058] In some embodiments, the clear aperture semi-diameter CSD11 of the object side end of the first lens and the sagitta SAGX11 of the clear aperture semi-diameter of the object side end of the first lens satisfy: -75 < CSD11 / SAGX11 < -50. By satisfying the above conditions, it is possible to avoid the surface profile of the object side surface of the first lens from being too curved, which is beneficial to the incidence of large-angle light rays into the lens, and thus beneficial to expanding the field angle of the lens and improving the imaging quality of the optical lens. At the same time, it is also beneficial to reducing the processing difficulty of the first lens and avoiding the uneven coating caused by the too-curved surface profile of the object side surface of the first lens; in addition, it can also avoid the surface profile of the object side surface of the first lens from being too flat, which is beneficial to reducing the risk of ghost images.

[0059] In some embodiments, the clear aperture semi-diameter CSD11 of the object side end of the first lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.5 < CSD11 / IH < 0.6. By satisfying the above conditions, by reasonably controlling the clear aperture semi-diameter of the object side surface of the first lens, the optical lens can have a certain large field angle and also have the imaging quality of a large image plane and high pixels.

[0060] In some embodiments, the Abbe number Vd1 of the first lens and the Abbe number Vd2 of the second lens satisfy: 75 < Vd1 + Vd2 < 90. By satisfying the above conditions, the chromatic aberration correction effect of the first lens and the second lens is improved; at the same time, it can also make the first two lenses of the chromatic aberration correction effect distributed at the front end of the optical lens, which is beneficial to improving the chromatic dispersion correction ability of the optical lens, and thus improving the imaging quality of the optical lens

[0061] In some embodiments, the clear aperture semi-diameter CSD32 of the image side end of the third lens and the clear aperture semi-diameter CSD41 of the object side end of the fourth lens satisfy: 1 < CSD32 / CSD41 < 1.2. By satisfying the above conditions, by reasonably distributing the maximum effective apertures of the third lens and the fourth lens, it is beneficial to reducing the step difference between the third lens and the fourth lens, so that light rays can enter the fourth lens more smoothly from the third lens.

[0062] In some embodiments, the maximum field of view FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 66° < FOV / Fno < 71°. Meeting the above conditional formula defines that the optical lens has an appropriate field of view and aperture value, can collect light at large angles, and obtain good imaging quality.

[0063] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -1.4 < f1 / f < -1.1. Meeting the above conditional formula, setting the first lens of the optical lens as a lens with a negative optical power can capture the light entering the optical lens at large angles, expand the field of view range of the optical lens; at the same time, it is also beneficial to reduce the sensitivity of the optical lens and achieve the miniaturized design of the optical lens.

[0064] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.5 < f6 / f < -1. Meeting the above conditions can make the sixth lens have an appropriate negative optical power, can reduce the deflection angle of the light in the sixth lens, reduce the sensitivity of the sixth lens, and can also reduce aberrations such as astigmatism and distortion generated by the lens group in front of the sixth lens, thereby being beneficial to improving the imaging quality of the optical lens.

[0065] In some embodiments, the curvature radius R1 of the object side surface of the first lens and the focal length f1 of the first lens satisfy: 24 < R1 / f1 < 29. Meeting the above conditional formula, by reasonably configuring the ratio of the curvature radius of the object side surface of the first lens to the effective focal length of the first lens, the marginal rays can be better converged into the optical lens, effectively expanding the field of view of the optical lens.

[0066] In some embodiments, the curvature radius R14 of the image side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 3.5 < R14 / f < 6. Meeting the above conditions can correct the spherical aberration of the lens and improve the imaging quality; and the surface shape of the image side surface of the seventh lens changes smoothly from the optical axis to the edge, converging the angles of the marginal field of view incident on the imaging surface and the marginal field of view aberration, improving the imaging quality.

[0067] In some embodiments, the optical lens satisfies the following conditional formula: 26mm < TTL ≤ 30mm; 1.7 ≤ Fno ≤ 1.8; 9.2mm < IH ≤ 9.7mm; 5mm < f < 5.2mm; FOV = 120°. In the above conditional formula, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view of the optical lens, f represents the effective focal length of the optical lens, and FOV represents the maximum field of view of the optical lens. Meeting the above conditional formula, the optical lens has at least one or more advantages such as miniaturization, large aperture, large image height, long focal length, and large field of view.

[0068] In some embodiments, the lens material of the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, production costs can be effectively reduced. Alternatively, when the lens material is glass, the inherent low dispersion of glass can effectively correct the geometric chromatic aberration of the optical system. The optical lens provided by the present invention can utilize an all-glass lens structure, which can reduce dispersion, effectively correct chromatic aberration of the optical lens, and improve imaging quality.

[0069] In some embodiments, the first, second, third, fourth, fifth, sixth, and seventh lenses may be spherical or aspherical lenses. Compared to spherical lenses, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number and size of lenses and achieving better miniaturization. More specifically, the first, second, fourth, fifth, and sixth lenses of the present invention may be spherical lenses; the third and seventh lenses may be aspherical lenses.

[0070] In various embodiments of the present invention, when the lens is an aspheric lens, the shapes of the aspheric surfaces of the optical lens satisfy the following equations:

[0071]

[0072] Where z is the distance between the surface and the vertex in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, 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.

[0073] The present invention is further illustrated below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens vary; for details, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the present invention is not limited thereto. Any other changes, substitutions, combinations, or simplifications that do not deviate from the novelties of the present invention shall be considered equivalent replacements and are included within the scope of protection of the present invention.

[0074] Example 1

[0075] See also Figure 1 , shown is a schematic structural diagram of the optical lens 100 provided in Example 1 of the present invention. The optical lens 100 includes, in order from the object side to the imaging surface along the optical axis: a first lens L1, a second lens L2, a third lens L3, an aperture ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0076] The first lens L1 has negative refractive power, its object-side surface S1 is concave, and its image-side surface S2 is concave;

[0077] The second lens L2 has negative refractive power, its object-side surface S3 is concave, and its image-side surface S4 is convex;

[0078] The third lens L3 has positive refractive power, its object-side surface S5 is convex, and its image-side surface S6 is concave;

[0079] The fourth lens L4 has positive refractive power, its object-side surface S7 is convex, and its image-side surface S8 is convex;

[0080] The fifth lens L5 has positive refractive power, its object-side surface S9 is convex, and its image-side surface is convex;

[0081] The sixth lens L6 has negative refractive power, its object-side surface is concave, and its image-side surface S11 is convex;

[0082] The fifth lens L5 and the sixth lens L6 form a cemented lens group with positive refractive power. That is, the cemented surface between the image-side surface of the fifth lens L5 and the object-side surface of the sixth lens is S10.

[0083] The seventh lens L7 has positive refractive power, its object-side surface S12 is convex near the optical axis, and its image-side surface S13 is concave near the optical axis;

[0084] The object-side surface S14 and the image-side surface S15 of the filter G1 are both flat surfaces;

[0085] The imaging surface S16 is a plane.

[0086] The third lens L3 and the seventh lens L7 are glass aspherical lenses; the first lens L1, the second lens L2, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are glass spherical lenses.

[0087] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0088] Table 1-1

[0089]

[0090]

[0091] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0092] Table 1-2

[0093] Face number K B C D E F S5 1.1857E+00 -1.7902E-04 -4.3361E-06 6.4713E-08 -4.5315E-09 3.4554E-11 S6 2.8022E+00 2.5008E-04 -8.4781E-06 1.6564E-06 -1.0568E-07 3.0812E-09 S12 1.2691E+01 -2.6379E-03 -3.7821E-05 -1.6810E-07 -1.8682E-07 9.8126E-09 S13 2.7950E+00 -2.3419E-03 -2.2833E-05 5.7584E-07 4.8154E-09 3.3727E-10

[0094] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 100 are shown as follows: Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 The blue line segment in each graph indicates a wavelength of 0.436um; the green line segment indicates a wavelength of 0.486um; the red line segment indicates a wavelength of 0.546um; the yellow line segment indicates a wavelength of 0.588um; and the purple line segment indicates a wavelength of 0.656um.

[0095] Figure 2 A field curvature graph of the optical lens 100 in this embodiment is shown, showing the field curvature of the optical lens within the wavelength range of 0.436 μm to 0.656 μm. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: degrees). The solid line represents the field curvature on the meridional image plane, and the dashed line represents the field curvature on the sagittal image plane. As can be seen from the graph, the field curvature of the meridional and sagittal image planes is controlled within ±0.03 mm, indicating that the optical lens 100 can effectively correct field curvature.

[0096] Figure 3 The F-Tan (Theta) distortion curve for Example 1 shows the distortion of the optical lens at a wavelength of 0.656 μm, specifically the F-Tan (Theta) distortion at different image heights on the imaging plane. The horizontal axis represents the F-Tan (Theta) distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-Tan (Theta) distortion of the optical lens is controlled within a range of -50% to 0%, and the image compression in the edge angle area is relatively smooth, effectively improving the clarity of the expanded image.

[0097] Figure 4 A graph showing the axial aberration of the optical lens 100 in this embodiment is shown, illustrating the axial aberration of the optical lens within a wavelength range of 0.436 μm to 0.656 μm. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the graph, the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 100 is capable of effectively correcting the axial aberration.

[0098] Figure 5A graph showing vertical chromatic aberration of the optical lens 100 in this embodiment is shown. It depicts the chromatic aberration of the optical lens at different image heights on the imaging plane within a wavelength range of 0.436 μm to 0.656 μm. The horizontal axis represents the vertical chromatic aberration value for each wavelength (unit: μm), and the vertical axis represents the half-field angle (unit:°). As can be seen from the graph, the vertical chromatic aberration for both the longest and shortest wavelengths is controlled within ±3 μm, demonstrating that the optical lens 100 is capable of effectively correcting chromatic aberration.

[0099] Example 2

[0100] See also Figure 6 , shown is a schematic structural diagram 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.

[0101] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0102] Table 2-1

[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 F S5 1.4520E+00 -8.3205E-05 -2.2833E-06 5.0568E-08 -4.5403E-09 1.9914E-10 S6 4.0050E+00 2.7806E-04 -8.9820E-06 1.6097E-06 -8.9229E-08 2.4988E-09 S12 -3.8472E+01 -3.0829E-03 -3.0359E-05 -1.6043E-06 -3.6074E-07 2.3706E-08 S13 2.2899E+01 -2.8478E-03 -1.5073E-05 4.0003E-07 6.3527E-09 6.3951E-10

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

[0108] from Figure 7 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.03 mm, indicating that the optical lens 200 can correct the field curvature well.

[0109] from Figure 8 It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 200 is controlled within -50% to 0, and the image compression in the edge angle area is relatively smooth, which effectively improves the clarity of the expanded image.

[0110] from Figure 9 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.03 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0111] from Figure 10 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±5μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0112] Example 3

[0113] See also Figure 11 , shown is a schematic structural diagram of an optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment has the following main differences: the fifth lens L5 and the sixth lens L6 form a cemented lens group with negative optical power; the image-side surface S11 of the sixth lens L6 is concave; and 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]

[0118] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0119] Table 3-2

[0120] Face number K B C D E F S5 1.3189E+00 -1.9332E-04 -7.5506E-06 3.0505E-07 -2.1551E-08 8.5566E-10 S6 -1.6495E+00 1.3571E-04 -9.7595E-06 1.0942E-06 -5.8277E-08 2.0411E-09 S12 -7.9858E+01 -1.2223E-03 -4.1684E-05 -2.9736E-06 2.9113E-07 -3.9407E-09 S13 9.4557E+00 -1.7316E-03 -6.0349E-06 -8.1905E-07 7.6637E-08 -7.3058E-10

[0121] In this embodiment, the field curvature curve, F-Tan (Theta) distortion curve, axial aberration curve, and vertical chromatic aberration curve of the optical lens 300 are shown as follows: Figure 12 、 Figure 13 、 Figure 14 、 Figure 15 shown.

[0122] from Figure 12 It can be seen from the figure that the field curvature of the meridional image plane and the sagittal image plane is controlled within ±0.04 mm, indicating that the optical lens 300 can correct the field curvature well.

[0123] from Figure 13 It can be seen from the figure that the F-Tan (Theta) distortion of the optical lens 300 is controlled within -50% to 0, and the image compression in the edge angle area is relatively smooth, which effectively improves the clarity of the expanded image.

[0124] from Figure 14 It can be seen from the figure that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0125] from Figure 15 It can be seen from the figure that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±4 μm, indicating that the optical lens 300 can correct chromatic aberration well.

[0126] Please refer to Table 4, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, real image height IH corresponding to the maximum field of view angle, 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, the optical lens provided by the present invention uses seven lenses with specific optical powers. Through the combination of specific surface shapes and reasonable optical power distribution, it is possible to improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, so that the lens has one or more advantages such as miniaturization, large aperture, large image height, large field of view, high pixel count, and high imaging quality.

[0131] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0132] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An optical lens, comprising seven lenses, characterized in that: Along the optical axis from the object side to the imaging surface, it includes: The first lens has a negative optical power, and its object-side surface is concave and its image-side surface is concave; a second lens having negative optical power, whose object-side surface is concave and whose image-side surface is convex; a third lens element having positive optical power, whose object-side surface is convex and whose image-side surface is concave; a fourth lens element having positive refractive power, whose object-side surface is convex and whose image-side surface is convex; a fifth lens element having positive refractive power, whose object-side surface and image-side surface are convex; a sixth lens element having negative optical power and a concave object-side surface; The seventh lens element has positive refractive power, its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis; The real image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens and the maximum field angle FOV of the optical lens satisfy the following conditions: 0.5<(IH / 2) / (f×tan(FOV / 2))<0.

55.

2. The optical lens according to claim 1, wherein: The total optical length TTL of the optical lens and the aperture value Fno of the optical lens meet the following requirements: 15mm <TTL / Fno<17mm。 3. The optical lens according to claim 1, wherein: The real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy the following conditions: 1.8 <IH / f<1.9。 4. The optical lens according to claim 1, wherein: The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 2.2 <f3 / f<5.5。 5. The optical lens according to claim 1, wherein: A curvature radius R3 of the object side surface of the second lens and a curvature radius R4 of the image side surface of the second lens satisfy: -10<(R3+R4) / (R3-R4)<-7.

5.

6. The optical lens according to claim 1, wherein: The focal length f2 of the second lens, the object side curvature radius R3 of the second lens, and the image side curvature radius R4 of the second lens satisfy: <f2 / (R3+R4)<19。 7. The optical lens according to claim 1, wherein: The semi-aperture CSD11 of the object side end of the first lens and the semi-aperture sag SAGX11 of the object side end of the first lens meet the following conditions: -75 <CSD11 / SAGX11<-50。 8. The optical lens according to claim 1, wherein: The object side semi-aperture CSD11 of the first lens and the real image height IH corresponding to the maximum field angle of the optical lens meet the following requirements: 0.5 <CSD11 / IH<0.6。 9. The optical lens according to claim 1, wherein: The Abbe number Vd1 of the first lens and the Abbe number Vd2 of the second lens satisfy: 75 <Vd1+Vd2<90。 10. The optical lens according to claim 1, wherein: The image side semi-aperture CSD32 of the third lens and the object side semi-aperture CSD41 of the fourth lens satisfy: 1 <CSD32 / CSD41<1.2。

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