Optical lens

Abstract

The invention provides an optical lens, which sequentially comprises a first lens with positive focal power from an object side to an imaging surface along an optical axis, a second lens with negative focal power, a third lens with positive focal power and a fourth lens with negative focal power from the object side to the imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has positive focal power, and the image side surface of the third lens is a convex surface; the fourth lens has positive focal power, and the object side surface of the fourth lens is a convex surface near the optical axis; the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has positive focal power, the object side surface of the sixth lens is a convex surface near the optical axis, and the image side surface of the sixth lens is a concave surface near the optical axis; and the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface near the optical axis. The optical lens provided by the invention has one or more advantages of large target surface, large aperture, miniaturization, 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] With the rapid development of electronic product performance and technology, people have higher and higher requirements for the shooting functions of portable electronic products. At present, the main camera of mainstream mobile phone lenses uses a target area smaller than 1 / 1.5 inches. Due to the constraints of limited pixels and pixel points, it is impossible to meet the requirements of high pixels and large pixel points at the same time. Insufficient light sensitivity in dark environments will cause a lot of noise to the image quality, resulting in reduced image quality and unclear imaging. Summary of the invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens having one or more advantages such as a large target surface, a large aperture, miniaturization, and high imaging quality.

[0004] The technical solution adopted by the present invention is: An optical lens, composed of seven lenses, including the following lenses in order from the object side to the imaging surface along the optical axis: The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; A third lens element having positive refractive power and a convex image-side surface; The fourth lens element has positive refractive power and its object side surface is convex near the optical axis; a fifth lens having positive refractive power, whose object side surface is concave and whose image side surface is convex; a sixth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; The seventh lens element has a negative optical power, the object side surface of which is concave, and the image side surface of which is concave near the optical axis; The total optical length TTL of the optical lens, the real image height ih corresponding to the maximum half field angle of the optical lens and the effective focal length f of the optical lens satisfy: 7.4 mm <TTL×(ih / f)<8.4mm。

[0005] Further preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 <TTL / f<1.4。

[0006] Further preferably, a sum ∑CT of the center thicknesses of the first lens to the seventh lens on the optical axis and a sum ∑AT of the spacing distances between any two adjacent lenses from the first lens to the seventh lens on the optical axis satisfy: 1.4<∑CT / ∑AT<2.2.

[0007] Further preferably, the total optical length TTL of the optical lens and the sum of the center thicknesses of the first lens to the fifth lens on the optical axis ΣCT15 satisfy: 2.3 <TTL / ∑CT15<2.8。

[0008] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 <f1 / f<1.35。

[0009] Further preferably, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 <f1 / f2<-0.3。

[0010] Further preferably, the semi-aperture CSD11 of the first lens on the object side and the semi-aperture CSD71 of the seventh lens on the object side satisfy the following conditions: 0.5 <CSD11 / CSD71<0.7。

[0011] Further preferably, the semi-aperture CSD11 of the first lens on the object side and the real image height ih corresponding to the maximum half-viewing angle of the optical lens satisfy the following relationship: 0.3 <CSD11 / ih<0.4。

[0012] Further preferably, the vector height SAGX71 corresponding to the maximum light semi-aperture of the object side end of the seventh lens and the center thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 <SAGX71 / CT7<-2.2。

[0013] Further preferably, the effective focal length f of the optical lens, the center thickness CT6 of the sixth lens on the optical axis, the distance CT67 between the sixth lens and the seventh lens on the optical axis, and the center thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 <f / (CT6+CT67+CT7)<2.9。

[0014] Further preferably, the center thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 <CT7 / ET7<0.7。

[0015] Compared with the prior art, the optical lens provided by the present invention has a small volume through a specific surface shape setting and a reasonable optical focal length distribution; it can also realize the large target surface characteristics of the lens, and can be matched with a large target surface chip, which is beneficial to improving the lens resolution and image detail restoration; the lens has a large aperture, and high-definition imaging can be achieved even in dim environments; it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has high pixels, thereby improving the imaging quality of the optical lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0017] Figure 2 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 1 of the present invention.

[0018] Figure 3 It is a field curvature curve diagram of the optical lens in Example 1 of the present invention.

[0019] Figure 4 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0020] Figure 5 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0021] Figure 6 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 2 of the present invention.

[0022] Figure 7 4 is a field curvature curve diagram of the optical lens in Example 2 of the present invention.

[0023] Figure 8 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0024] Fig. 9 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0025] Fig.10 Graph showing the F-Tan (Theta) distortion of the optical lens in Example 3 of the present invention.

[0026] Fig.11 4 is a field curvature curve diagram of the optical lens in Example 3 of the present invention.

[0027] Fig.12 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0028] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The following will detail the present application with reference to the accompanying drawings and in combination with the embodiments.

[0036] The optical lens provided by the embodiment of the present invention is composed of seven lenses, which are, 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.

[0037] In some embodiments, the first lens may have a positive optical power, its object side is convex, and its image side is concave. The second lens may have a negative optical power, its object side is convex, and its image side is concave. The third lens may have a positive optical power, its object side may be concave or convex, and its image side is convex. The fourth lens may have a positive optical power, its object side is convex near the optical axis, and its image side may be concave or convex. The fifth lens may have a positive optical power, its object side is concave, and its image side is convex. The sixth lens may have a positive optical power, its object side is convex near the optical axis, and its image side is concave near the optical axis. The seventh lens may have a negative optical power, its object side is concave, and its image side is concave near the optical axis.

[0038] 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 is used to limit the amount of incident light to change the brightness of the image.

[0039] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the seventh 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.

[0040] In some embodiments, the total optical length TTL of the optical lens, the true image height ih corresponding to the maximum half field of view angle of the optical lens, and the effective focal length f of the optical lens satisfy: 7.4mm < TTL×(ih / f) < 8.4mm. When the above conditions are met, by restricting the total length of the optical lens, it is ensured that the optical lens meets the large imaging surface and has good enough imaging quality; at the same time, it also enables the imaging lens to meet the requirements of high pixels and large pixel points, making the pixel point size larger under the same number of pixels, reducing noise in a dark environment, and retaining more details in the dark part, thereby obtaining high imaging quality.

[0041] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 < TTL / f < 1.4. When the above conditions are met, it is possible to reasonably control the distribution of the total length and the optical focal length of the optical lens, shorten the total length of the optical lens, reduce the sensitivity of the optical lens, and then match it with the image sensor to improve the imaging quality of the optical lens.

[0042] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens on the optical axis respectively and the sum ∑AT of the spacing distances between any two adjacent lenses among the first lens to the seventh lens on the optical axis satisfy: 1.4 < ∑CT / ∑AT < 2.2. When the above conditions are met, by reasonably controlling the sum of the central thicknesses of the lenses of the optical lens, the distortion range of the optical lens can be reasonably controlled, so that the optical lens has a small distortion.

[0043] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT15 of the central thicknesses of the first lens to the fifth lens on the optical axis respectively satisfy: 2.3 < TTL / ∑CT15 < 2.8. When the above conditions are met, the proportion of the sum of the central thicknesses of the first five lenses of the optical lens in the total optical length can be reasonably restricted, which is beneficial to improving the structural compactness of the optical lens, realizing a miniaturized design, and preventing the length ratio of the first five lenses in the optical lens from being too large, so as to help prevent a large deflection of the incident light when entering the sixth lens, and further help suppress aberrations and improve the imaging quality of the optical lens.

[0044] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 < f1 / f < 1.35. When the above conditions are met, by restricting the ratio of the focal length of the first lens to the focal length of the optical lens, it is beneficial to reasonably configure the refractive power of the first lens to support the large field of view angle and large aperture characteristics of the optical lens, is beneficial to converging the incident light entering the optical lens from the object side, reducing the deflection angle, is beneficial to the aberration balance of the optical lens, and improves the imaging quality of the optical lens.

[0045] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 < f1 / f2 < -0.3. When the above conditions are met, the effective focal lengths of the first lens and the second lens can be reasonably configured to effectively balance the chromatic aberration of the optical lens and reduce the performance sensitivity of the optical lens, making the performance of the optical lens more stable.

[0046] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the clear aperture semi-diameter CSD71 at the object side end of the seventh lens satisfy: 0.5 < CSD11 / CSD71 < 0.7. When the above conditions are met, the clear aperture semi-diameters of the object side surfaces of the first lens and the seventh lens can be reasonably configured, which is beneficial to restricting the size of the first lens, so that the optical lens can achieve a small head design, and further can improve the screen-to-body ratio of the electronic device equipped with the optical lens; and it can also provide a large entrance pupil for the optical lens to expand the aperture, so that the optical lens has sufficient light transmission, and further improves the imaging quality of the optical lens.

[0047] In some embodiments, the clear aperture semi-diameter CSD11 at the object side end of the first lens and the true image height ih corresponding to the maximum semi-field angle of the optical lens satisfy: 0.3 < CSD11 / ih < 0.4. When the above conditions are met, it can ensure that the optical lens has a relatively large clear aperture and a relatively large imaging surface, enabling a reasonable balance between the large light passing amount and the large imaging surface of the optical lens, which helps to improve the imaging quality.

[0048] In some embodiments, the sagittal height SAGX71 corresponding to the maximum clear aperture semi-diameter at the object side end of the seventh lens and the central thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 < SAGX71 / CT7 < -2.2. When the above conditions are met, the incident angle of the chief ray on the object side surface of the seventh lens can be effectively reduced, and the matching degree between the optical lens and the photosensitive chip can be improved.

[0049] In some embodiments, the effective focal length f of the optical lens, the central thickness CT6 of the sixth lens on the optical axis, the spacing CT67 between the sixth lens and the seventh lens on the optical axis, and the central thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 < f / (CT6 + CT67 + CT7) < 2.9. When the above conditions are met, by reasonably setting the central thickness and spacing of the sixth lens and the seventh lens, the astigmatism of the optical lens can be effectively balanced, and the contribution of the distortion of the sixth lens and the seventh lens can be restricted, improving the imaging quality of the optical lens and helping to shorten the total length of the optical lens.

[0050] In some embodiments, the central thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 < CT7 / ET7 < 0.7. When the above conditions are met, the central thickness and edge thickness of the seventh lens can be reasonably configured, so that the deflection angle of the light passing through the seventh lens is smaller, reducing the generation of stray light in the optical lens and improving the imaging quality of the optical lens; the ratio of the central thickness and edge thickness of the seventh lens is beneficial to the injection molding and assembly of the seventh lens, improving the injection molding yield of the seventh lens and reducing the production cost of the seventh lens.

[0051] In some embodiments, the total optical length TTL of the optical lens and the true image height ih corresponding to the maximum semi-field angle of the optical lens satisfy: 0.65 < TTL / (ih × 2) < 0.75. When the above conditions are met, the size of the large image surface optical lens can be restricted, which is beneficial to reducing the volume of the optical lens, saving space and controlling the cost of the optical lens at the same time.

[0052] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -3.4 < f2 / f < -2.8. When the above conditions are met, it is beneficial for the refractive power of the second lens to be properly matched in the optical lens, the surface shape design of the second lens is more simple and flexible, the aberration is reduced, and the aberration correction of the overall optical lens and the balance of the imaging quality are simplified.

[0053] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 1.7 < f5 / f < 3.3. When the above conditions are met, it is beneficial for the fifth lens to gently diffuse the light beam, laying a foundation for the optical lens to achieve large image plane imaging, thereby improving the imaging quality of the optical lens.

[0054] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -0.85 < f7 / f < -0.6. When the above conditions are met, the deflection angle of the light in the seventh lens can be reduced, the sensitivity of the seventh lens can be lowered, and the aberrations such as astigmatism and distortion generated by the lens group in front of the seventh lens can also be reduced, thereby being beneficial to improving the imaging quality of the optical lens.

[0055] In some embodiments, the radius of curvature R1 of the object side surface of the first lens and the effective focal length f of the optical lens satisfy: 0.4 < R1 / f < 0.5. When the above conditions are met, it is beneficial to maintain the astigmatism of the first lens within a reasonable range, enabling the optical system to have good imaging quality.

[0056] In some embodiments, the central thickness CT1 of the first lens on the optical axis and the edge thickness ET1 of the first lens satisfy: 1.8 < CT1 / ET1 < 3.6. When the above conditions are met, by controlling the central thickness and the edge thickness of the first lens within a certain range, the aberration generated by the optical lens can be effectively balanced, and it is also beneficial for the field curvature adjustment in engineering production, thereby being beneficial to improving the imaging quality of the optical lens.

[0057] In some embodiments, the optical lens satisfies the conditional formula: 8.3 mm < TTL < 9 mm, 6.5 mm < f < 7.2 mm, 6 mm < ih < 6.5 mm, 1.5 < Fno < 1.7, 80° < FOV < 88°; where, TTL represents the overall optical length of the optical lens, f represents the effective focal length of the optical lens, ih represents the true image height corresponding to the maximum half field of view angle of the optical lens, Fno represents the aperture value of the optical lens, and FOV represents the maximum field of view angle 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 a large target surface, a large aperture, and miniaturization.

[0058] 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. 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 optical lens provided by the present invention can adopt a full plastic lens structure, which not only makes the lens have excellent imaging performance, but also makes the structure of the lens more compact, and can better achieve a balance between miniaturization of the lens and high image quality.

[0059] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens may be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and reducing the size of lenses, and better realizing miniaturization of lenses. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention may all be aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and reducing the size of lenses, and better realizing miniaturization of lenses.

[0060] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations: ; Among them, 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 surface vertex, K is the quadratic surface coefficient, B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0061] 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.

[0062] Example 1 See also Figure 1 , which is a schematic diagram of the structure of the optical lens 100 provided in Embodiment 1 of the present invention, wherein the optical lens includes, in sequence from the object side to the imaging surface along the optical axis: 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, a seventh lens L7 and a filter G1.

[0063] The first lens L1 has positive refractive power, its object side surface S1 is convex, and its image side surface S2 is concave; The second lens L2 has negative refractive power, its object-side surface S3 is convex, and its image-side surface S4 is concave; The third lens L3 has positive refractive power, its object-side surface S5 is concave, and its image-side surface S6 is convex; The fourth lens L4 has positive refractive power, an object-side surface S7 thereof is convex at the near optical axis, and an image-side surface S8 thereof is concave at the near optical axis; The fifth lens L5 has positive refractive power, its object-side surface S9 is concave, and its image-side surface S10 is convex; The sixth lens L6 has positive refractive power, an object-side surface S11 thereof is convex at the near optical axis, and an image-side surface S12 thereof is concave at the near optical axis; The seventh lens L7 has negative refractive power, its object-side surface S13 is concave, and its image-side surface S14 is concave at the near optical axis; The object side surface S15 and the image side surface S16 of the filter G1 are both planes; The imaging surface S17 is a plane.

[0064] 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.

[0065] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0066] Table 1-1 The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0067] Table 1-2 Figure 2 The F-Tan (Theta) distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion of different field angles on the imaging plane, 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 value is controlled within ±2%, indicating that the optical lens 100 can correct the distortion well.

[0068] Figure 3The field curvature curve of the optical lens 100 in this embodiment is shown, which represents the field curvature of light in the meridional image plane and the sagittal image plane, the horizontal axis represents the offset (unit: mm), and the vertical axis represents 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 ±0.1mm, indicating that the optical lens 100 can correct the field curvature well.

[0069] 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 ±3.5 μm, indicating that the optical lens 100 can correct the chromatic aberration well.

[0070] Example 2 See also Figure 5 , 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 differences of this embodiment are: the object side surface S5 of the third lens L3 is a convex surface at the near optical axis; the image side surface S8 of the fourth lens is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0071] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0072] Table 2-1 The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0073] Table 2-2 In this embodiment, the F-Tan (Theta) distortion curve, the field curvature curve, and the vertical axis chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 6 , Figure 7 , Figure 8 shown.

[0074] from Figure 6 It can be seen that the distortion value is controlled within ±2%, indicating that the optical lens 200 can correct the distortion well.

[0075] from Figure 7 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.05mm, indicating that the optical lens 200 can correct the field curvature well.

[0076] from Figure 8 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±2.5 μm, indicating that the optical lens 200 can correct the chromatic aberration well.

[0077] Example 3 See also Fig. 9 , 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 differences of this embodiment are: the object side surface S5 of the third lens L3 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0078] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0079] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0080] Table 3-2 In this embodiment, the F-Tan (Theta) distortion curve, the field curvature curve, and the vertical axis chromatic aberration curve of the optical lens 300 are respectively as follows: Fig.10 , Fig.11 , Fig.12 shown.

[0081] from Fig.10 It can be seen that the distortion value is controlled within ±3%, indicating that the optical lens 300 can correct the distortion well.

[0082] from Fig.11 It can be seen that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.05mm, indicating that the optical lens 300 can correct the field curvature well.

[0083] from Fig.12 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 300 can correct the chromatic aberration well.

[0084] 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 half field of view angle, the chief ray incident angle CRA at the maximum image height, the maximum field of view FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0085] Table 4 In summary, the optical lens provided by the present invention has at least the following advantages: The optical lens provided by the present invention has a small volume through a specific surface shape setting and a reasonable distribution of optical focal length; it can also realize the large target surface characteristic of the lens, and can be matched with a large target surface chip, which is beneficial to improving the lens resolution and the detail restoration of the image; the lens has a large aperture, and high-definition imaging can be achieved even in a dim environment; it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has a high pixel, and the imaging quality of the optical lens is improved.

[0086] 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.

[0087] 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, consisting of seven lenses, characterized in that: Along the optical axis from the object side to the imaging surface, it includes: The first lens has positive refractive power, its object side surface is convex, and its image side surface is concave; The second lens has a negative optical power, its object side surface is convex, and its image side surface is concave; A third lens element having positive refractive power and a convex image-side surface; The fourth lens element has positive refractive power and its object side surface is convex near the optical axis; a fifth lens having positive refractive power, whose object side surface is concave and whose image side surface is convex; a sixth lens having positive refractive power, whose object side surface is convex at the near optical axis and whose image side surface is concave at the near optical axis; The seventh lens element has a negative optical power, the object side surface of which is concave, and the image side surface of which is concave near the optical axis; The total optical length TTL of the optical lens, the real image height ih corresponding to the maximum half field angle of the optical lens and the effective focal length f of the optical lens satisfy: 7.4 mm <TTL×(ih / f)<8.4mm。 2. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.2 <TTL / f<1.4。 3. The optical lens according to claim 1, characterized in that: A sum ΣCT of the center thicknesses of the first lens to the seventh lens on the optical axis and a sum ΣAT of the spacing distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 1.4<ΣCT / ΣAT<2.

2.

4. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the sum of the center thicknesses of the first lens to the fifth lens on the optical axis ΣCT15 satisfy: 2.3 <TTL / ∑CT15<2.8。 5. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 0.95 <f1 / f<1.35。 6. The optical lens according to claim 1, characterized in that: The focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.5 <f1 / f2<-0.3。 7. The optical lens according to claim 1, characterized in that: The semi-aperture CSD11 of the first lens on the object side and the semi-aperture CSD71 of the seventh lens on the object side satisfy: 0.5 <CSD11 / CSD71<0.7。 8. The optical lens according to claim 1, characterized in that: The semi-aperture CSD11 of the first lens on the object side and the real image height ih corresponding to the maximum half-viewing angle of the optical lens satisfy the following conditions: 0.3 <CSD11 / ih<0.4。 9. The optical lens according to claim 1, characterized in that: The vector height SAGX71 corresponding to the maximum light semi-aperture of the object side end of the seventh lens and the center thickness CT7 of the seventh lens on the optical axis satisfy: -6.3 <SAGX71 / CT7<-2.2。 10. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens, the center thickness CT6 of the sixth lens on the optical axis, the distance CT67 between the sixth lens and the seventh lens on the optical axis, and the center thickness CT7 of the seventh lens on the optical axis satisfy: 2.1 <f / (CT6+CT67+CT7)<2.9。 11. The optical lens according to claim 1, characterized in that: The center thickness CT7 of the seventh lens on the optical axis and the edge thickness ET7 of the seventh lens satisfy: 0.4 <CT7 / ET7<0.7。

Images