Optical lens

Abstract

The application provides an optical lens, which comprises, in sequence along an optical axis from the direction of light propagation, a first optical element with negative optical power, the first optical element adopting a fold-back prism structure; a second lens with positive optical power, the object side and the image side of the second lens being both convex; a third lens with negative optical power, the object side and the image side of the third lens being both concave; a fourth lens with positive optical power, the object side of the fourth lens being convex and the image side of the fourth lens being concave; a fifth lens with negative optical power, the object side of the fifth lens being concave; a sixth lens with negative optical power, the object side of the sixth lens being concave and the image side of the sixth lens being convex; the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 1.9 < f / IH < 2.2. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and make the lens have one or more advantages such as periscopic long focus, large image surface, high pixel, high imaging quality and the like.

Description

Technical Field

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

[0002] With the development of mobile phone camera technology, mobile phone shooting functions have gradually become richer, giving rise to optical lenses with different functions such as front-facing small lenses, telephoto lenses, zoom lenses, and wide-angle lenses. However, in response to market demands, mobile phones are becoming increasingly thinner and lighter, thus requiring the camera lenses used in mobile phones to adapt accordingly. Periscope lenses, by aligning the lens's length with the plane of the mobile phone, break the limitation imposed by the phone's thickness on the lens length. Besides requiring telephoto capabilities and a miniaturized form factor, periscope lenses also demand excellent imaging performance, necessitating the development of an optical lens with superior imaging capabilities. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0004] The technical solution adopted in this invention is as follows:

[0005] An optical lens, comprising, in sequence along the optical axis from the direction of light propagation:

[0006] A first optical element with negative optical power, the first optical element adopts a folding prism structure, the first optical element includes an incident surface, a reflecting surface and an exiting surface, the incident surface is concave and the exiting surface is planar;

[0007] A second lens with positive optical power has convex surfaces on both its object-side and image-side surfaces.

[0008] A third lens with negative optical power has concave object-side and image-side surfaces;

[0009] The fourth lens with positive optical power has a convex object side and a concave image side.

[0010] The fifth lens has negative optical power and its object side is concave.

[0011] The sixth lens with negative optical power has a concave object side and a convex image side.

[0012] Wherein, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 1.9 <f / IH<2.2。

[0013] Further preferably, the total equivalent optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.3 < TTL / f < 1.6.

[0014] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first optical element satisfy: -9 < f1 / f < -6.

[0015] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 0.3 < f2 / f < 0.6; 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: -0.3 < R3 / R4 < -0.1.

[0016] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -0.6 < f3 / f < -0.3.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.2.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -10 < f5 / f < -2.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -7 < f6 / f < -4.

[0020] Further preferably, the propagation path CT1 of light in the first optical element, the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, the central thickness CT4 of the fourth lens, the central thickness CT5 of the fifth lens, and the central thickness CT6 of the sixth lens satisfy: 0.9 < CT1 / (CT2 + CT3 + CT4 + CT5 + CT6) < 1.

[0021] Further preferably, the effective focal length f of the optical lens and the radius of curvature R1 of the incident surface of the first optical element satisfy: -10 < R1 / f < -2.

[0022] Further preferably, the back focal length BFL of the optical lens and the total equivalent optical length TTL of the optical lens satisfy: 0.3 < BFL / TTL < 0.4.

[0023] The optical lens provided by this invention, through specific surface shape matching and reasonable optical power distribution, enables the lens to achieve a periscope telephoto effect, reduce the lens size, and also has the characteristics of long focal length and shallow depth of field, which can better present larger local details, making the image more focused and compact, thereby meeting the needs of local shooting; at the same time, the optical lens also has a large image plane and high resolution, which can match the larger chip size to achieve high-definition imaging; it can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens, giving the lens one or more advantages such as periscope telephoto, large image plane, high pixel, and high imaging quality. Attached Figure Description

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

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

[0026] Figure 2 for Figure 1 Equivalent structural diagram.

[0027] Figure 3 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

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

[0029] Figure 5 This is an axial aberration curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6 This is a schematic diagram of the equivalent structure of the optical lens in Embodiment 2 of the present invention.

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

[0032] Figure 8 This is a chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 9 This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 10 This is a schematic diagram of the equivalent structure of the optical lens in Embodiment 3 of the present invention.

[0035] Figure 11 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 12This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 13 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 14 This is a schematic diagram of the equivalent structure of the optical lens in Embodiment 4 of the present invention.

[0039] Figure 15 This is a field curvature curve diagram of the optical lens in Embodiment 4 of the present invention.

[0040] Figure 16 This is a chromatic aberration curve of the optical lens in Embodiment 4 of the present invention.

[0041] Figure 17 This is an axial aberration curve of the optical lens in Embodiment 4 of the present invention.

[0042] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0043] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0048] 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 application 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 specified herein.

[0049] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] The optical lens provided in this embodiment of the invention comprises, along the optical axis and from the direction of light propagation, a first optical element, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens.

[0051] In some embodiments, the first optical element may have negative optical power; the second lens may have positive optical power, with both its object-side and image-side surfaces being convex; the third lens may have negative optical power, with both its object-side and image-side surfaces being concave; the fourth lens may have positive optical power, with its object-side surface being convex and its image-side surface being concave; the fifth lens may have negative optical power, with its object-side surface being concave; and the sixth lens may have negative optical power, with its object-side surface being concave and its image-side surface being convex.

[0052] In some embodiments, the first optical element may be a folding prism structure, comprising an incident surface, a reflecting surface, and an exit surface. The incident surface may be concave or aspherical; the exit surface may be planar. Light rays originating from the object-side direction enter the prism from the incident surface, are reflected by the reflecting surface, and then exit from the exit surface. By setting up the folding prism, the direction of the light path can be changed, bending the light path so that the direction of the incident light rays is perpendicular to the arrangement direction of the multiple lenses, reducing the overall thickness of the optical system; at the same time, it can also converge the angle of the incident light, which is beneficial for achieving the periscope-like long focal length effect of the lens. Specifically, the first optical element may be a right-angled triangular prism.

[0053] In some embodiments, the optical lens may further include an aperture, which may be located between the first optical element and the second lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image formation.

[0054] In some embodiments, the optical lens may further include a filter, which may be disposed between the sixth lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0055] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.9 < f / IH < 2.2. Meeting the above conditions can not only achieve the telephoto characteristics of the lens to meet the local shooting requirements, but also achieve the large image plane characteristics of the lens, be able to carry a larger size chip, and achieve high-definition imaging of the lens.

[0056] In some embodiments, the equivalent optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.3 < TTL / f < 1.6. Meeting the above conditions is beneficial to the miniaturization of the lens and can better achieve the balance between the miniaturization of the lens and the telephoto performance.

[0057] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first optical element satisfy: -9 < f1 / f < -6. Meeting the above conditions, the first optical element adopts the design of a catadioptric prism, and the prism has a certain negative refractive power, so that the prism can not only be used for deflecting the incident light, but also converge the angle of the incident light, which is beneficial to achieving the effect of a long focal length of the lens.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 0.3 < f2 / f < 0.6; 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: -0.3 < R3 / R4 < -0.1. Meeting the above range, the second lens has a strong positive refractive power and a biconvex surface type, which can effectively converge the light rays emitted from the prism, is beneficial to correcting various aberrations generated in the prism, and is also beneficial to achieving the telephoto performance of the lens.

[0059] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -0.6 < f3 / f < -0.3. The curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy: -0.3 < R5 / R6 < -0.03. Meeting the above conditions, by reasonably setting the focal length and surface type of the third lens, it is beneficial to the smooth transition of light rays, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens.

[0060] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.2. The radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: 0.8 < R7 / R8 < 1.1. By satisfying the above conditions, through reasonable setting of the focal length and surface shape of the fourth lens, the contribution of spherical aberration of the fourth lens can be controlled within a reasonable range, enabling the lens to have a high on-axis imaging resolution ability, which is beneficial to achieving high-definition imaging of the lens.

[0061] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -10 < f5 / f < -2. By satisfying the above conditions, it is beneficial to balance various aberrations in the optical lens and improve the overall imaging quality of the optical lens.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -7 < f6 / f < -4. The radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: 0.7 < R11 / R12 < 0.9. By satisfying the above conditions, through reasonable adjustment of the focal length and surface shape of the sixth lens, it is beneficial to increase the divergence degree of light, increase the area of light entering the imaging surface, achieve large target surface imaging of the lens, and improve the imaging quality of the optical lens.

[0063] In some embodiments, the propagation path CT1 of light in the first optical element, the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, the central thickness CT4 of the fourth lens, the central thickness CT5 of the fifth lens, and the central thickness CT6 of the sixth lens satisfy: 0.9 < CT1 / (CT2 + CT3 + CT4 + CT5 + CT6) < 1. By satisfying the above range, the first optical element adopts a catadioptric prism design, and the propagation path of light in the catadioptric prism is the equivalent central thickness of the first optical element. By setting the first optical element to have a large optical thickness, the angle of incident light can be effectively converged, and the long focal length and shallow depth of field effects of the lens can be better achieved.

[0064] In some embodiments, the back focal length BFL of the optical lens and the total equivalent optical length TTL of the optical lens satisfy: 0.3 < BFL / TTL < 0.4. By satisfying the above conditions, while achieving miniaturization of the lens, the lens can have a large back focus, which is beneficial to the assembly of the module, reduces interference, and improves production yield.

[0065] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R1 of the incident surface of the first optical element satisfy: -10 < R1 / f < -2. Meeting the above conditions, the first optical element adopts the design of a folding prism, and the R1 surface of the prism adopts an aspherical design, so that the prism can not only be used to deflect the incident light, but also converge the angle of the incident light, and is beneficial to the lens achieving the effect of a long focal length.

[0066] In some embodiments, the focal length f2 of the second lens and the focal length f3 of the third lens satisfy: -1.1 < f2 / f3 < -0.8. Meeting the above conditions can correct the marginal aberration of the optical lens and improve the imaging resolution.

[0067] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.6 < f3 / f4 < -0.3. Meeting the above conditions is beneficial to correcting the axial aberration of the optical lens and improving the imaging quality of the optical lens; at the same time, it can also improve the angle of ghost light between the third lens and the fourth lens and reduce the ghost energy.

[0068] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: 0.6 < f5 / f6 < 1.5. Meeting the above conditions, by reasonably setting the focal length relationship of the last two negative lenses in the lens, while collecting as much light as possible into the system, the light transmission amount of the system is increased, and large-field imaging of the lens is achieved.

[0069] In some embodiments, the optical lens satisfies the following conditional expressions: 15 mm < f < 20 mm; 20° < FOV < 35°; 25 mm < TTL < 30 mm; 8 mm < IH < 10 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, TTL represents the equivalent optical total length of the optical lens (i.e., the propagation path distance of light from the incident surface of the first optical element to the imaging surface), and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as a long focal length and a large image plane.

[0070] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The second lens, the third lens, the fourth lens, the fifth lens and the sixth lens provided by the present invention can adopt a plastic lens structure, which can make the structure of the lens relatively compact, and can better achieve the balance of miniaturization and high image quality of the lens and reduce the cost.

[0071] In some embodiments, the second, third, fourth, fifth, and sixth lenses can be spherical or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number of lenses and their size, and better achieving lens miniaturization. More specifically, the second, third, fourth, fifth, and sixth lenses of this invention are all aspherical lenses.

[0072] In various embodiments of the present invention, when an aspherical lens is used, the shapes of each aspherical surface of the optical lens satisfy the following equations:

[0073]

[0074] 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 B, C, D, E, F, G, and H are the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order surface coefficients, respectively.

[0075] 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.

[0076] Example 1

[0077] Please see Figure 1 and Figure 2 , Figure 1 and Figure 2 These are all schematic diagrams of the optical lens 100 provided in Embodiment 1 of the present invention. For ease of understanding, this application will... Figure 1 The optical lens coordinate system of the folding structure is transformed into... Figure 2 An optical coordinate system with a linear structure. It is understandable that, compared to... Figure 1 , Figure 2 The first optical element L1 in the diagram is illustrated using a conventional lens of equivalent thickness.

[0078] The optical lens 100 includes, in sequence along the optical axis from the direction of light propagation: a first optical element L1, an aperture ST, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter G1.

[0079] The first optical element L1 has negative optical power and adopts a folding prism design, specifically a right-angled triangular prism, including an incident surface S1, a reflecting surface R0, and an exit surface S2. The incident surface S1 can be concave or aspherical, while the exit surface S2 can be planar. It is understood that the incident surface S1 faces the object side, and the exit surface S2 faces the imaging plane.

[0080] The second lens L2 has positive optical power, and its object side surface S3 and image side surface S4 are both convex surfaces.

[0081] The third lens L3 has negative optical power, and its object side S5 and image side S6 are both concave.

[0082] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is concave.

[0083] The fifth lens L5 has negative optical power, its object side S9 is concave, and its image side S10 is convex.

[0084] The sixth lens L6 has negative optical power, its object side S11 is concave, and its image side S12 is convex.

[0085] The object-side surface S13 and the image-side surface S14 of filter G1 are both planar.

[0086] The imaging plane S15 is a plane.

[0087] The second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are all plastic aspherical lenses.

[0088] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0089] Table 1-1

[0090]

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

[0092] Table 1-2

[0093]

[0094]

[0095] In this embodiment, the field curvature curve, transverse chromatic aberration curve, and axial aberration curve of the optical lens 100 are respectively as follows: Figure 3 , Figure 4 , Figure 5 As shown.

[0096] Figure 3 The field curvature curve of Example 1 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 field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within -0.15 mm to 0.05 mm, indicating that the optical lens 100 can effectively correct the field curvature.

[0097] Figure 4 The diagram shows the transverse chromatic aberration curves for Example 1, representing the chromatic aberration of each wavelength relative to the center wavelength (0.555 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 diagram, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1.5 μm, indicating that the optical lens 100 can effectively correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0098] Figure 5 The axial aberration curve of Embodiment 1 is shown, which represents the aberration of each wavelength on 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 ±0.06 mm, indicating that the optical lens 100 can correct the axial aberration well.

[0099] Example 2

[0100] Please see Figure 6 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface 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]

[0105] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0106] Table 2-2

[0107] Face number K B C D E F G H S1 -1.18E+02 -6.89E-05 -1.71E-05 -7.54E-07 3.72E-08 4.66E-10 -1.02E-10 6.98E-13 S3 -4.77E-01 -3.21E-03 1.13E-04 6.76E-06 3.44E-06 -3.76E-07 -1.68E-08 2.31E-09 S4 -6.20E+01 -2.90E-03 1.03E-04 -9.87E-06 -1.97E-06 8.41E-07 -8.60E-08 3.18E-09 S5 -2.85E+01 1.34E-02 -2.01E-03 9.48E-05 -1.32E-05 3.92E-06 -3.11E-07 4.40E-09 S6 -2.00E+02 2.12E-02 -2.90E-03 1.44E-04 5.12E-05 -2.17E-05 5.16E-06 -3.92E-07 S7 -4.36E+00 4.08E-03 1.17E-04 7.73E-06 2.97E-06 -2.65E-06 1.72E-06 -2.10E-07 S8 -5.94E+00 3.50E-03 5.48E-04 -2.49E-04 2.02E-04 -7.96E-05 1.34E-05 -1.59E-06 S9 -2.00E+02 -4.67E-03 7.40E-04 1.34E-04 -1.91E-04 9.86E-05 -2.41E-05 1.17E-06 S10 2.00E+02 2.04E-02 -7.19E-04 -9.50E-04 1.55E-04 -5.87E-06 -1.14E-06 5.92E-07 S11 -6.07E+01 1.75E-02 2.72E-04 -1.07E-03 2.65E-05 7.02E-05 -1.84E-05 1.63E-06 S12 -4.93E+01 3.27E-03 4.27E-05 -4.18E-05 -5.26E-05 1.24E-05 -1.12E-06 4.32E-08

[0108] In this embodiment, the field curvature curve, transverse chromatic aberration curve, and axial aberration curve of the optical lens 200 are respectively as follows: Figure 7 , Figure 8 , Figure 9 As shown.

[0109] from Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.06mm to 0.15mm, indicating that the optical lens 200 can effectively correct the field curvature.

[0110] from Figure 8 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1.5μm, indicating that the optical lens 200 can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0111] from Figure 9 As can be seen, the axial aberration offset is controlled within ±0.08mm, indicating that the optical lens 200 can correct axial aberration well.

[0112] Example 3

[0113] Please see Figure 10 The figure shows a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the image side surface S10 of the fifth lens L5 is concave, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

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

[0115] Table 3-1

[0116]

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

[0118] Table 3-2

[0119]

[0120]

[0121] In this embodiment, the field curvature curve, transverse chromatic aberration curve, and axial aberration curve of the optical lens 300 are respectively as follows: Figure 11 , Figure 12 , Figure 13 As shown.

[0122] from Figure 11 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.1mm to 0.15mm, indicating that the optical lens 300 can effectively correct field curvature.

[0123] from Figure 12 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1.5μm, indicating that the optical lens 300 can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0124] from Figure 13 As can be seen, the axial aberration offset is controlled within ±0.08mm, indicating that the optical lens 300 can correct axial aberration well.

[0125] Example 4

[0126] Please see Figure 14 The figure shown is a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that the image side surface S10 of the fifth lens L5 is concave, and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0127] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0128] Table 4-1

[0129]

[0130]

[0131] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0132] Table 4-2

[0133] Face number K B C D E F G H S1 -9.15E+01 -7.74E-05 -1.75E-05 -7.20E-07 3.87E-08 3.69E-10 -1.10E-10 1.24E-12 S3 -4.43E-01 -3.16E-03 1.16E-04 7.41E-06 3.46E-06 -3.79E-07 -1.68E-08 2.31E-09 S4 -7.57E+01 -2.87E-03 1.04E-04 -9.62E-06 -1.94E-06 8.38E-07 -8.64E-08 3.21E-09 S5 -2.85E+01 1.34E-02 -2.01E-03 9.47E-05 -1.33E-05 3.92E-06 -3.10E-07 4.44E-09 S6 -1.17E+01 2.12E-02 -2.90E-03 1.44E-04 5.07E-05 -2.18E-05 5.14E-06 -3.88E-07 S7 -4.45E+00 4.44E-03 1.55E-04 7.91E-06 3.28E-06 -2.96E-06 1.66E-06 -1.97E-07 S8 -6.72E+00 4.12E-03 8.05E-04 -2.35E-04 1.99E-04 -7.85E-05 1.37E-05 -1.78E-06 S9 -2.00E+02 -4.95E-03 5.95E-04 1.46E-04 -1.90E-04 9.66E-05 -2.38E-05 1.16E-06 S10 -1.96E+02 1.99E-02 -8.86E-04 -1.01E-03 1.52E-04 -4.12E-06 -7.62E-07 4.70E-07 S11 -5.80E+01 1.78E-02 2.53E-04 -1.07E-03 2.67E-05 6.96E-05 -1.85E-05 1.67E-06 S12 -4.75E+01 3.32E-03 6.65E-05 -4.07E-05 -5.26E-05 1.23E-05 -1.13E-06 4.51E-08

[0134] In this embodiment, the field curvature curve, transverse chromatic aberration curve, and axial aberration curve of the optical lens 400 are respectively as follows: Figure 15 , Figure 16 , Figure 17 As shown.

[0135] from Figure 15 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 400 can effectively correct field curvature.

[0136] from Figure 16 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±1.5μm, indicating that the optical lens 400 can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0137] from Figure 17As can be seen, the axial aberration offset is controlled within ±0.08mm, indicating that the optical lens 400 can correct axial aberration well.

[0138] Please refer to Table 5 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, equivalent total optical length TTL, aperture value Fno, principal ray incident angle CRA at the maximum image height, true image height IH corresponding to the maximum field of view, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0139] Table 5

[0140]

[0141]

[0142] In summary, the optical lens provided by the present invention has at least the following advantages:

[0143] (1) By combining specific surface shapes and reasonable focal length distribution, the lens can achieve the effect of a periscope telephoto lens. This not only reduces the size of the lens but also provides the characteristics of long focal length and shallow depth of field, enabling it to better present larger local details and make the image more focused and compact, thus meeting the needs of local shooting. It also enables the lens to achieve the characteristics of a large image plane, allowing it to carry a larger chip and achieve high-definition imaging. At the same time, it can improve the imaging quality of the optical lens, reduce aberrations, and improve the imaging quality of the optical lens.

[0144] (2) The design of the reflective prism bends the light path and reduces the overall thickness of the optical system. At the same time, the incident surface of the prism is aspherical, which not only changes the direction of the incident light, but also narrows the angle of the incident light, which is beneficial to increasing the focal length of the lens and optimizing various aberrations.

[0145] 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.

[0146] 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 characterized in that, In order from the direction of light propagation along the optical axis, comprising in sequence: a first optical element with negative focal power, the first optical element adopts a fold-back prism structure, the first optical element comprises an incident surface, a reflection surface and an exit surface, the incident surface is a concave surface, and the exit surface is a plane; a second lens with positive focal power, both the object side surface and the image side surface of the second lens are convex surfaces; a third lens with negative focal power, both the object side surface and the image side surface of the third lens are concave surfaces; a fourth lens with positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a concave surface; a fifth lens with negative focal power, the object side surface of the fifth lens is a concave surface; a sixth lens with negative focal power, the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a convex surface; wherein the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.9 < f / IH < 2.

2.

2. The optical lens of claim 1, wherein, The equivalent total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.3 < TTL / f < 1.

6.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f1 of the first optical element satisfy: -9 < f1 / f < -6.

4. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 0.3 < f2 / f < 0.6; the object side surface curvature radius R3 of the second lens and the image side surface curvature radius R4 of the second lens satisfy: -0.3 < R3 / R4 < -0.

1.

5. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: -0.6 < f3 / f < -0.

3.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 0.9 < f4 / f < 1.

2.

7. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -10 < f5 / f < -2.

8. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -7 < f6 / f < -4.

9. The optical lens of claim 1, wherein, The propagation distance CT1 of the light in the first optical element, the central thickness CT2 of the second lens, the central thickness CT3 of the third lens, the central thickness CT4 of the fourth lens, the central thickness CT5 of the fifth lens and the central thickness CT6 of the sixth lens satisfy: 0.9 < CT1 / (CT2+CT3+CT4+CT5+CT6) < 1.

10. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the incident surface curvature radius R1 of the first optical element satisfy: -10 < R1 / f < -2.

11. The optical lens of claim 1, wherein, The back focal length BFL of the optical lens and the equivalent total optical length TTL of the optical lens satisfy: 0.3 < BFL / TTL < 0.4.

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