Optical lens

Abstract

The application provides an optical lens, which comprises, in sequence from an object side to an imaging surface along an optical axis, an aperture stop, a first lens with positive refractive power, whose object side is convex and whose image side is concave, a second lens with negative refractive power, whose image side is concave, a third lens with positive refractive power, whose image side is convex, a fourth lens with negative refractive power, a fifth lens with positive refractive power, whose object side is concave and whose image side is convex, a sixth lens with negative refractive power, whose object side is convex near the optical axis and whose image side is concave near the optical axis, and a seventh lens with negative refractive power, whose object side is concave and whose image side is concave near the optical axis, wherein the sum of the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the effective focal length f3 of the third lens and the effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: -80.0 < (f1+f2+f3+f4) / f < -35.0. The application realizes the effects of large field of view, large aperture and miniaturization.

Description

Technical Field

[0001] This invention relates to the field of imaging lens technology, and in particular to an optical lens. Background Technology

[0002] In recent years, with the rapid upgrading of consumer electronics products such as mobile phones and tablets, the market demands for imaging lenses have become increasingly diversified. In addition to requiring imaging lenses to have a slim and compact form factor and high pixel count and high resolution, products also need imaging lenses with a wide field of view.

[0003] In view of this, the present invention proposes an optical lens with characteristics such as large aperture, excellent imaging quality, wide angle, and miniaturization, suitable for portable electronic products. Summary of the Invention

[0004] The purpose of this invention is to provide an optical lens that has at least the advantages of a large field of view, a large aperture, and miniaturization.

[0005] To achieve the aforementioned objective, this invention provides an optical lens comprising seven lenses, arranged sequentially along the optical axis from the object side to the image plane: an aperture stop; a first lens with positive optical power, its object side being convex and its image side being concave; a second lens with negative optical power, its image side being concave; a third lens with positive optical power, its image side being convex; a fourth lens with negative optical power; a fifth lens with positive optical power, its object side being concave and its image side being convex; and a sixth lens with negative optical power. The object-side surface of the lens is convex near the optical axis, and the image-side surface is concave near the optical axis; the seventh lens with negative optical power has an object-side surface that is concave and an image-side surface that is concave near the optical axis; wherein, the sum of the effective focal lengths f1 of the first lens, f2 of the second lens, f3 of the third lens, and f4 of the fourth lens and the effective focal length f of the optical lens satisfy: -80.0 < (f1 + f2 + f3 + f4) / f < -35.0.

[0006] Compared with existing technologies, the optical lens provided by this invention has a reasonable combination of optical power, lens surface shape, lens thickness and inter-lens spacing, achieving the effects of large field of view, large aperture and miniaturization. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the structure of the optical lens in Embodiment 1 of the present invention.

[0008] Figure 2 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0009] Figure 3This is the F-Thetaθ distortion curve of the optical lens in Embodiment 1 of the present invention.

[0010] Figure 4 This is a relative illumination curve of the optical lens in Embodiment 1 of the present invention.

[0011] Figure 5 This is an MTF curve of the optical lens in Embodiment 1 of the present invention.

[0012] Figure 6 This is an axial aberration curve of the optical lens in Embodiment 1 of the present invention.

[0013] Figure 7 This is a chromatic aberration curve of the optical lens in Embodiment 1 of the present invention.

[0014] Figure 8 This is a schematic diagram of the optical lens structure of Embodiment 2 of the present invention.

[0015] Figure 9 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0016] Figure 10 This is the F-Thetaθ distortion curve of the optical lens in Embodiment 2 of the present invention.

[0017] Figure 11 This is a relative illumination curve of the optical lens in Embodiment 2 of the present invention.

[0018] Figure 12 This is the MTF curve of the optical lens in Embodiment 2 of the present invention.

[0019] Figure 13 This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0020] Figure 14 This is a chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0021] Figure 15 This is a schematic diagram of the optical lens structure of Embodiment 3 of the present invention.

[0022] Figure 16 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0023] Figure 17 This is the F-Thetaθ distortion curve of the optical lens in Embodiment 3 of the present invention.

[0024] Figure 18 This is a relative illumination curve of the optical lens in Embodiment 3 of the present invention.

[0025] Figure 19This is an MTF curve of the optical lens in Embodiment 3 of the present invention.

[0026] Figure 20 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0027] Figure 21 This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention. Detailed Implementation

[0028] To better understand the invention, various aspects of the invention will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of the invention and are not intended to limit the scope of the invention 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.

[0029] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0030] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0031] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0032] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of the invention, the word "may" is used to mean "one or more embodiments of the invention." And the term "exemplary" is intended to refer to an example or illustration.

[0033] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] This invention provides an optical lens that, from the object side to the imaging plane, comprises, in sequence: an aperture stop, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and a filter, with the optical centers of each lens located on the same straight line.

[0036] In some embodiments, the first lens may have positive optical power, with its object-side surface being convex and its image-side surface being concave; the second lens may have negative optical power, with its image-side surface being concave; the third lens may have positive optical power, with its image-side surface being convex; the fourth lens may have negative optical power; the fifth lens may have positive optical power, with its object-side surface being concave and its image-side surface being convex; the sixth lens may have negative optical power, with its object-side surface being convex near the optical axis and its image-side surface being concave near the optical axis; and the seventh lens may have negative optical power, with its object-side surface being concave and its image-side surface being concave near the optical axis.

[0037] In some embodiments, the maximum field of view (FOV) of the optical lens satisfies: 84° ≤ FOV. Meeting this range facilitates the achievement of wide-angle characteristics, thereby enabling the acquisition of more scene information and meeting the needs of large-area detection.

[0038] In some embodiments, the sum of the effective focal lengths f1 of the first lens, f2 of the second lens, f3 of the third lens, and f4 of the fourth lens, and the effective focal length f of the optical lens satisfy the following condition: -80.0 < (f1 + f2 + f3 + f4) / f < -35.0. Meeting this range allows for a reasonable allocation of the optical power of the first to fourth lenses, which is beneficial for achieving effects such as thinness, miniaturization, and large aperture.

[0039] In some embodiments, the center thickness CT4 of the fourth lens, the air gap AT45 between the fourth and fifth lenses on the optical axis, and the center thickness CT5 of the fifth lens satisfy the following condition: 2.0 < (CT4 + AT45) / CT5 < 2.3. Meeting this range allows for the reduction of light bending trends in the off-axis field of view by reasonably adjusting the center thicknesses of the fourth and fifth lenses and the spacing between them. This helps correct distortion and field curvature added by the optical lens, reduces the impact on lens sensitivity, and improves the imaging quality of the optical lens.

[0040] In some embodiments, the effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -4.0 < f2 / f < 0; the radius of curvature R21 of the object side of the second lens and the radius of curvature R22 of the image side of the second lens satisfy: 0 < (R21 + R22) / (R21 - R22) < 3.0. By satisfying these ranges and rationally setting the optical power and surface shape of the second lens, it is beneficial to mitigate the optical refracting tendency, reduce the sensitivity of the optical lens, effectively correct the aberrations of the optical lens, and improve the imaging quality of the optical lens.

[0041] In some embodiments, the sum of the center thickness CT2 of the second lens and the center thickness CT3 of the third lens, and the sum of the air gaps AT12, AT23, and AT34 on the optical axis between the first and second lenses, respectively, satisfy the following condition: 1.0 < (CT2 + CT3) / (AT12 + AT23 + AT34) < 1.2. By satisfying this range and rationally setting the center thicknesses of the second and third lenses and the spacing between adjacent lenses from the first to the fourth lens, the structure of the first to fourth lenses can be made more compact, which is beneficial for reducing the head size of the optical lens and achieving miniaturization of the optical lens.

[0042] In some embodiments, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy the following condition: 1.7 < f / EPD < 1.9. Meeting this range is beneficial for achieving large aperture characteristics and ensuring image clarity even in low-light environments or at night.

[0043] In some embodiments, the half-image height (IMH) of the optical lens and the back focal length (BFL) of the optical lens satisfy the following condition: 5.6 < IMH / BFL < 6.0. Meeting this range allows for a balance between a large image plane and a short back focal length by appropriately adjusting the ratio of image height to back focal length.

[0044] In some embodiments, the radius of curvature R41 of the object-side surface of the fourth lens and the radius of curvature R42 of the image-side surface of the fourth lens satisfy: 7.0 < (R41 + R42) / (R41 - R42) < 11.0. Meeting this range allows for the reduction of shape changes in the fourth lens and a decrease in the light refraction angle by reasonably adjusting the radii of curvature of the object-side and image-side surfaces of the fourth lens. This is beneficial for correcting aberrations and field curvature of the optical lens and improving its imaging quality.

[0045] In some embodiments, the radii of curvature R51 of the object-side surface of the fifth lens, R52 of the image-side surface of the fifth lens, R61 of the object-side surface of the sixth lens, R62 of the image-side surface of the sixth lens, R21 of the object-side surface of the second lens, and R22 of the image-side surface of the second lens satisfy the following condition: 0.5 < (R51 × R52 × R61 × R62) / (R21 × R22) < 1.5. Meeting this range, by rationally setting the optical power and surface shape of the second, fifth, and sixth lenses, is beneficial for effectively correcting the primary aberrations of the optical lens and improving the imaging quality of the optical lens.

[0046] In some embodiments, the center thickness CT6 of the sixth lens and the center thickness CT5 of the fifth lens satisfy the following condition: 1.2 < CT6 / CT5 < 1.5. By satisfying the above range and reasonably allocating the center thicknesses of the fifth and sixth lenses, the thicknesses of the fifth and sixth lenses can be made appropriate, reducing molding sensitivity, improving assembly yield, and at the same time, it is beneficial to correct aberrations and distortions of the optical lens, thereby improving the imaging quality of the optical lens.

[0047] In some embodiments, the effective diameter D71 of the object-side surface of the seventh lens, the effective diameter D62 of the image-side surface of the sixth lens, and the sag SAG71 of the object-side surface of the seventh lens satisfy: -2.0 < (D71 - D62) / SAG71 < -1.5. By satisfying this range and reasonably adjusting the surface shapes of the sixth and seventh lenses, the manufacturability of the seventh lens can be guaranteed, its sensitivity reduced, and it is also beneficial for correcting aberrations in the optical lens, resulting in a high-pixel count.

[0048] In some embodiments, the sum of the center thicknesses of the first to seventh lenses along the optical axis, ∑CT, and the sum of the air gaps along the optical axis between adjacent lenses, ∑AT, satisfy the condition: 1.6 < ∑CT / ∑AT < 1.7. By satisfying this range and rationally allocating the thickness of each lens and the inter-lens spacing, the structure of the optical lens can be made more compact, which is beneficial for miniaturizing the optical lens.

[0049] In some embodiments, the maximum field of view (FOV) of the optical lens and the total optical length (TTL) of the optical lens satisfy the following condition: 6.2 < Tan(FOV / 2) × TTL < 6.5. By satisfying the above range and reasonably controlling the field of view and total optical length of the optical lens, the optical lens can have both a large field of view and the characteristics of miniaturization.

[0050] To achieve better optical performance, the lens employs multiple aspherical lenses, and the shapes of each aspherical surface of the optical lens satisfy the following equation:

[0051]

[0052] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and A, B, C, D, E, F, G, H, and I are the second, fourth, sixth, eighth, tenth, twelfth, fourteenth, sixteenth, and eighteenth order surface coefficients, respectively.

[0053] The present invention will be further described below with reference to several 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 tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0054] First Embodiment

[0055] Please see Figure 1 The figure shown is a schematic diagram of the structure of the optical lens provided in the first embodiment of the present invention. The optical lens includes, along the optical axis from the object side to the imaging surface S17, the following components in sequence: aperture ST, first lens L1, second lens L2, third lens L3, fourth lens L4, fifth lens L5, sixth lens L6, seventh lens L7, and filter G1.

[0056] Specifically, the first lens L1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave; the second lens L2 has negative optical power, with its object-side surface S3 being convex near the optical axis and its image-side surface S4 being concave; the third lens L3 has positive optical power, with its object-side surface S5 being convex near the optical axis and its image-side surface S6 being convex; the fourth lens L4 has negative optical power, with its object-side surface S7 being convex near the optical axis and its image-side surface S8 being concave near the optical axis; and the fifth lens L5 has positive optical power, with its object-side surface S9 being concave. The image side S10 is convex; the sixth lens L6 has negative optical power, its object side S11 is convex near the optical axis, and its image side S12 is concave near the optical axis; the seventh lens L7 has negative optical power, its object side S13 is concave, and its image side S14 is concave near the optical axis; the object side of the filter G1 is S15, and its image side is S16; among them, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are all plastic aspherical lenses.

[0057] The relevant parameters of each lens in the optical lens of this embodiment are shown in Table 1.

[0058] Table 1

[0059]

[0060]

[0061] The surface profile parameters of the aspherical lens of the optical lens in this embodiment are shown in Table 2.

[0062] Table 2

[0063] Face number K A B C D S1 -6.42E-02 4.38E-03 1.09E-03 3.28E-04 4.76E-04 S2 2.83E+00 -4.14E-03 -1.48E-03 1.60E-03 -6.45E-04 S3 0.00E+00 -4.15E-02 1.31E-02 2.08E-03 -1.70E-03 S4 2.97E+01 -3.78E-02 7.97E-04 3.76E-03 -8.25E-04 S5 1.23E+01 -1.92E-03 -1.08E-02 -1.01E-02 5.32E-03 S6 0.00E+00 -2.57E-02 4.09E-03 -1.74E-03 -7.95E-03 S7 0.00E+00 -1.08E-01 5.92E-03 -9.22E-03 5.19E-04 S8 0.00E+00 -7.55E-02 6.61E-05 -1.34E-03 5.76E-04 S9 -1.53E-02 1.92E-02 -4.24E-03 -1.64E-03 6.32E-04 S10 -4.65E-01 2.47E-02 7.12E-04 3.04E-05 1.36E-04 S11 1.21E+01 -3.35E-02 3.06E-03 -8.69E-04 1.36E-04 S12 -6.60E+01 -1.97E-02 6.34E-04 -9.44E-05 6.90E-06 S13 -7.23E-01 -2.01E-03 7.88E-04 1.33E-04 -1.21E-05 S14 -1.36E+02 -1.45E-02 1.85E-03 -1.28E-04 3.06E-06 Face number E F G H I S1 9.66E-05 -1.72E-04 6.13E-05 0.00E+00 0.00E+00 S2 4.66E-04 -3.01E-04 5.54E-05 0.00E+00 0.00E+00 S3 2.83E-04 -4.05E-05 8.84E-05 -6.96E-05 2.09E-05 S4 -4.87E-04 -2.47E-04 1.04E-04 2.26E-04 -1.01E-04 S5 -1.10E-03 -6.54E-04 1.71E-04 3.08E-04 -1.47E-04 S6 1.90E-03 2.77E-03 -1.58E-03 9.55E-05 4.57E-05 S7 7.83E-04 -2.15E-04 9.85E-05 0.00E+00 0.00E+00 S8 5.91E-04 -4.26E-04 1.55E-04 0.00E+00 0.00E+00 S9 6.39E-05 -7.15E-05 1.28E-05 -9.61E-08 -9.83E-08 S10 2.29E-05 -1.06E-05 5.00E-07 -1.53E-08 1.08E-08 S11 -9.40E-06 -1.14E-06 1.27E-07 1.81E-08 -1.13E-09 S12 1.41E-06 -1.07E-07 -1.36E-08 1.46E-10 1.10E-10 S13 -5.10E-07 7.84E-08 -1.42E-09 -7.84E-11 2.38E-12 S14 -1.13E-07 9.88E-09 -7.07E-11 -2.82E-12 -2.29E-13

[0064] Figure 2 The field curvature curve of this embodiment is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.1 mm, indicating that the optical lens can correct the field curvature very well.

[0065] Figure 3 The F-Thetaθ distortion curve of this embodiment is shown, which represents the F-Thetaθ distortion of light of different wavelengths at different image heights on the imaging plane. The horizontal axis represents F-Thetaθ distortion (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-Thetaθ distortion of the optical lens is controlled within ±2.5%, indicating that the optical lens can effectively correct F-Thetaθ distortion.

[0066] Figure 4 The relative illumination curves of this embodiment are shown, representing the relative illumination values ​​at different field-of-view angles on the imaging plane. The horizontal axis represents the half-field-of-view angle (unit: °), and the vertical axis represents the relative illumination (unit: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 20% at the maximum half-field-of-view angle, indicating that the optical lens has good relative illumination.

[0067] Figure 5 The modulation transfer function (MTF) curve of this embodiment is shown, representing the lens imaging modulation at different spatial frequencies in each field of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this embodiment is above 0.4 throughout the entire field of view. Within the range of 0–120 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, exhibiting good image quality and good detail resolution at both low and high frequencies.

[0068] Figure 6 The axial aberration curves of this embodiment are shown, representing the aberrations of each wavelength along the optical axis at the imaging plane. 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 figure, the axial aberration offset is controlled within ±0.03 mm, indicating that the optical lens can effectively correct axial aberrations.

[0069] Figure 7 The transverse chromatic aberration curve of this embodiment is shown, representing the chromatic aberration of each wavelength relative to the center wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the figure, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2 μm, indicating that this optical lens can excellently correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0070] Second Embodiment

[0071] Please see Figure 8 The figure shown is a schematic diagram of the structure of the optical lens provided in the second embodiment of the present invention. The main difference between this embodiment and the first embodiment is that the curvature radius and thickness of each lens are different.

[0072] The relevant parameters of each lens in the optical lens of this embodiment are shown in Table 3.

[0073] Table 3

[0074]

[0075] The surface profile parameters of the aspherical lens in this embodiment are shown in Table 4:

[0076] Table 4

[0077]

[0078]

[0079] Figures 9 to 14 The field curvature curve, F-Thetaθ distortion curve, relative illumination curve, modulation transfer function (MTF) curve, axial aberration curve, and transverse chromatic aberration curve of this embodiment are shown respectively. As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens can correct field curvature very well; the F-Thetaθ distortion of the optical lens is controlled within ±2.0%, indicating that the optical lens can correct F-Thetaθ distortion well; the relative illumination value of the optical lens is still greater than 20% at the maximum half field of view, indicating that the optical lens has good relative illumination; the MTF value of this embodiment is above 0.45 throughout the entire field of view, and the MTF curve decreases smoothly and evenly from the center to the edge of the field of view in the range of 0 to 120 lp / mm, showing good imaging quality and good detail resolution at both low and high frequencies; the axial aberration offset is controlled within ±0.04mm, indicating that the optical lens can correct axial aberration well; the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2.2μm, indicating that the optical lens can correct chromatic aberration at the edge of the field of view and the second-order spectrum of the entire image plane very well.

[0080] Third Embodiment

[0081] Please see Figure 15 The figure shown is a schematic diagram of the structure of the optical lens provided in the third embodiment of the present invention. The main difference between this embodiment and the first embodiment is that the curvature radius and thickness of each lens are different.

[0082] The relevant parameters of each lens in the optical lens of this embodiment are shown in Table 5.

[0083] Table 5

[0084]

[0085]

[0086] The surface profile parameters of the aspherical lens in this embodiment are shown in Table 6:

[0087] Table 6

[0088]

[0089]

[0090] Figures 16 to 21 The field curvature curve, F-Thetaθ distortion curve, relative illumination curve, modulation transfer function (MTF) curve, axial aberration curve, and transverse chromatic aberration curve of this embodiment are shown respectively. As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens can effectively correct field curvature; the F-Thetaθ distortion of the optical lens is controlled within ±2.5%, indicating that the optical lens can effectively correct F-Thetaθ distortion; the relative illumination value of the optical lens is still greater than 20% at the maximum half field of view, indicating that the optical lens has good relative illumination; the MTF value of this embodiment is above 0.45 throughout the entire field of view, and the MTF curve decreases smoothly and evenly from the center to the edge of the field of view in the range of 0 to 120 lp / mm, showing good imaging quality and good detail resolution at both low and high frequencies; the axial aberration offset is controlled within ±0.35mm, indicating that the optical lens can effectively correct axial aberration; the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±2.2μm, indicating that the optical lens can excellently correct chromatic aberration at the edge of the field of view and the second-order spectrum of the entire image plane.

[0091] Please refer to Table 7 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, true image height IH, entrance pupil diameter EPD, field of view FOV, and the numerical values ​​corresponding to each conditional expression.

[0092] Table 7

[0093]

[0094]

[0095] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions 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 one or more embodiments or examples.

[0096] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens, wherein the optical lens comprises seven lenses, characterized in that, Along the optical axis from the object side to the imaging plane, the order is as follows: Aperture; A first lens with positive optical power, wherein the object side of the first lens is convex and the image side of the first lens is concave; A second lens with negative optical power, wherein the image-side surface of the second lens is concave; A third lens with positive optical power, wherein the image-side surface of the third lens is convex; A fourth lens with negative optical power; A fifth lens with positive optical power, wherein the object-side surface of the fifth lens is concave and the image-side surface of the fifth lens is convex; A sixth lens with negative optical power, wherein the object-side surface of the sixth lens is convex near the optical axis and the image-side surface of the sixth lens is concave near the optical axis; A seventh lens with negative optical power, wherein the object-side surface of the seventh lens is concave and the image-side surface of the seventh lens is concave near the optical axis; Wherein, the sum of the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the effective focal length f3 of the third lens, and the effective focal length f4 of the fourth lens, together with the effective focal length f of the optical lens, satisfies: -80.0 < (f1 + f2 + f3 + f4) / f < -35.

0.

2. The optical lens according to claim 1, characterized in that, The center thickness CT4 of the fourth lens, the air gap AT45 between the fourth lens and the fifth lens on the optical axis, and the center thickness CT5 of the fifth lens satisfy: 2.0 < (CT4 + AT45) / CT5 < 2.3; the sum of the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the effective focal length f3 of the third lens, and the effective focal length f4 of the fourth lens, and the effective focal length f of the optical lens satisfy: -77.00 ≤ (f1 + f2 + f3 + f4) / f ≤ -37.

34.

3. The optical lens according to claim 1, characterized in that, The effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -4.0 < f2 / f < 0; the radius of curvature R21 of the object side of the second lens and the radius of curvature R22 of the image side of the second lens satisfy: 0 < (R21 + R22) / (R21 - R22) < 3.

0.

4. The optical lens according to claim 1, characterized in that, The sum of the center thickness CT2 of the second lens and the center thickness CT3 of the third lens, and the sum of the air gaps AT12, AT23, and AT34 on the optical axis between the first and second lenses, satisfy the following: 1.0 < (CT2 + CT3) / (AT12 + AT23 + AT34) < 1.

2.

5. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy the following condition: 1.7 < f / EPD < 1.

9.

6. The optical lens according to claim 1, characterized in that, The half-image height (IMH) of the optical lens and the back focal length (BFL) of the optical lens satisfy the following condition: 5.6 < IMH / BFL < 6.

0.

7. The optical lens according to claim 1, characterized in that, The radius of curvature R41 of the object side of the fourth lens and the radius of curvature R42 of the image side of the fourth lens satisfy: 7.0 < (R41 + R42) / (R41 - R42) < 11.

0.

8. The optical lens according to claim 1, characterized in that, The curvature radii R51 of the object-side surface of the fifth lens, R52 of the image-side surface of the fifth lens, R61 and R62 of the object-side surface of the sixth lens, and R21 and R22 of the object-side surface of the second lens satisfy the following condition: 0.5 mm. 2 <(R51×R52×R61×R62) / (R21×R22)<1.5mm 2 .

9. The optical lens according to claim 1, characterized in that, The center thickness CT6 of the sixth lens and the center thickness CT5 of the fifth lens satisfy the following condition: 1.2 < CT6 / CT5 < 1.

5.

10. The optical lens according to claim 1, characterized in that, The effective diameter D71 of the object side of the seventh lens, the effective diameter D62 of the image side of the sixth lens, and the sagitta SAG71 of the object side of the seventh lens satisfy: -2.0 < (D71-D62) / SAG71 < -1.

5.

11. The optical lens according to claim 1, characterized in that, The sum of the center thicknesses of the first lens to the seventh lens on the optical axis, ∑CT, and the sum of the air gaps on the optical axis between adjacent lenses from the first lens to the seventh lens, ∑AT, satisfy: 1.6 < ∑CT / ∑AT < 1.7.

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