Optical lens

Abstract

The present invention provides an optical lens, which sequentially includes, along the optical axis from the object side to the imaging surface: a first lens with positive optical power, both its object side and image side being convex surfaces; a second lens with negative optical power, both its object side and image side being concave surfaces; a third lens with positive optical power, its image side being a convex surface; a fourth lens with negative optical power, its object side being a concave surface and its image side being a convex surface; a fifth lens with negative optical power, its image side being concave near the optical axis; wherein, the effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 5mm < f / Fno < 5.3mm. The optical lens provided by the present invention, through specific surface shape settings and reasonable optical power distribution, enables the lens to have telephoto characteristics and also has a compact large-aperture structure, effectively shortening the overall length of the optical lens and improving the imaging quality of the optical lens.

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 mobile communications and imaging technology, users' demand for mobile phone photography is no longer limited to daily recording, but they are increasingly inclined to pursue more professional and diversified photography experiences; for this reason, most flagship phones are equipped with a telephoto lens with digital zoom to achieve 10x or even 100x optical zoom capabilities, greatly improving the telephoto capabilities of mobile phones. However, the common 5-element telephoto lenses on the market are difficult to meet the requirements of large aperture, long focal length, and high illumination. Summary of the invention

[0003] In view of the above problems, the object of the present invention is to provide an optical lens having the advantages of long focus, large aperture, high illumination, and excellent imaging quality.

[0004] The technical solution adopted by the present invention is:

[0005] An optical lens, comprising five lenses, which include:

[0006] A first lens having positive refractive power, whose object side surface and image side surface are both convex;

[0007] The second lens has negative optical power, and both the object side surface and the image side surface are concave;

[0008] A third lens element having positive refractive power and a convex image-side surface;

[0009] a fourth lens having negative optical power, whose object side surface is concave and whose image side surface is convex;

[0010] The fifth lens element has negative power and its image side surface is concave at the near optical axis;

[0011] The effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 5mm <f / Fno<5.3mm。

[0012] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -0.9 <f2 / f<-0.5。

[0013] Further preferably, the combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45 of the fourth lens and the fifth lens satisfy: <f123 / f45<-0.6。

[0014] Further preferably, the effective focal length f of the optical lens, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: <f / (f1+f2)<-2.5。

[0015] Further preferably, a curvature radius R3 of the object side surface of the second lens and a curvature radius R4 of the image side surface of the second lens satisfy: 0.4<(R3+R4) / (R3-R4)<0.9.

[0016] Further preferably, the combined focal length f123 of the first lens, the second lens and the third lens, the center thickness CT1 of the first lens, the center thickness CT2 of the second lens and the center thickness CT3 of the third lens satisfy: 1.6 <f123 / (CT1+CT2+CT3)<2.1。

[0017] Further preferably, the entrance pupil diameter EPDI of the optical lens and the largest semi-aperture diameter CSD_MAX of the first lens to the fifth lens satisfy: 1.7 <EPDI / CSD_MAX<2.1。

[0018] Further preferably, the effective focal length f of the optical lens, the focal length f1 of the first lens and the focal length f3 of the third lens satisfy: 7 mm <f1×f3 / f<18mm。

[0019] Further preferably, the aperture value Fno of the optical lens satisfies: Fno≤2.1.

[0020] Further preferably, the center thickness CT1 of the first lens, the center thickness CT2 of the second lens, the center thickness CT4 of the fourth lens, and the center thickness CT5 of the fifth lens satisfy: 1.1<(CT1+CT2) / (CT4+CT5)<1.7.

[0021] Compared with the prior art, the optical lens provided by the present invention has a telephoto characteristic through a specific surface shape setting and a reasonable distribution of optical power, which can better present larger local details, make the picture more concentrated and compact, and thus meet the local shooting needs; while effectively shortening the overall length of the optical lens, it also has a compact large aperture structure, so that the optical lens can obtain sufficient light intake, and then the optical lens can obtain sufficient relative illumination when performing telephoto, thereby improving the imaging quality of the optical lens. In addition, the optical lens of the present invention can also reasonably correct the overall aberration of the optical lens, has small distortion, and improves the imaging quality of the optical lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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:

[0023] Figure 1 Schematic diagram of the structure of the optical lens in Example 1 of the present invention.

[0024] Figure 2 Graph showing the astigmatism of the optical lens in Example 1 of the present invention.

[0025] Figure 3 4 is a distortion curve diagram of the optical lens f~tan(θ) in Example 1 of the present invention.

[0026] Figure 4 Graph showing the axial aberration of the optical lens in Example 1 of the present invention.

[0027] Figure 5 Graph showing the vertical axis chromatic aberration of the optical lens in Example 1 of the present invention.

[0028] Figure 6 This is a relative illumination curve diagram of the optical lens in Example 1 of the present invention.

[0029] Figure 7 Schematic diagram of the structure of the optical lens in Example 2 of the present invention.

[0030] Figure 8 Graph showing the astigmatism of the optical lens in Embodiment 2 of the present invention.

[0031] Fig. 9 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 2 of the present invention.

[0032] Fig.10 Graph showing the axial aberration of the optical lens in Embodiment 2 of the present invention.

[0033] Fig.11 Graph showing the vertical axis chromatic aberration of the optical lens in Example 2 of the present invention.

[0034] Fig.12 This is a relative illumination curve diagram of the optical lens in Example 2 of the present invention.

[0035] Fig.13 Schematic diagram of the structure of the optical lens in Example 3 of the present invention.

[0036] Fig.14 4 is an astigmatism curve diagram of the optical lens in Example 3 of the present invention.

[0037] Fig.15 4 is a distortion curve diagram of f~tan(θ) of the optical lens in Example 3 of the present invention.

[0038] Fig.16 Graph showing the axial aberration of the optical lens in Embodiment 3 of the present invention.

[0039] Fig.17 Graph showing the vertical axis chromatic aberration of the optical lens in Example 3 of the present invention.

[0040] Fig.18 This is a relative illumination curve diagram of the optical lens in Example 3 of the present invention.

[0041] Fig.19 Schematic diagram of the structure of the optical lens in Example 4 of the present invention.

[0042] Fig. 20 4 is an astigmatism curve diagram of the optical lens in Example 4 of the present invention.

[0043] Fig.21 4 is a distortion curve diagram of the optical lens f~tan(θ) in Example 4 of the present invention.

[0044] Fig. 22 4 is an axial aberration curve diagram of the optical lens in Example 4 of the present invention.

[0045] Fig.23 Graph showing the vertical axis chromatic aberration of the optical lens in Example 4 of the present invention.

[0046] Fig.24 This is a relative illumination curve diagram of the optical lens in Example 4 of the present invention.

[0047] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0055] The optical lens provided by the embodiment of the present invention comprises five lenses in total, which are a first lens, a second lens, a third lens, a fourth lens and a fifth lens in order from the object side to the imaging surface along the optical axis.

[0056] In some embodiments, the first lens may have positive power, and its object side and image side are both convex. The second lens may have negative power, and its object side and image side are both concave. The third lens may have positive power, and its object side may be concave or convex, and its image side is convex. The fourth lens may have negative power, and its object side is concave, and its image side is convex. The fifth lens may have negative power, and its object side may be concave or convex, and its image side is concave at the near optical axis.

[0057] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the object side and the first lens. It is understood that the aperture is used to limit the amount of incoming light to change the brightness of the image.

[0058] In some embodiments, the optical lens may further include a filter, which may be disposed between the fifth 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.

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

[0060] In some embodiments, the effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 5mm < f / Fno < 5.3mm. By adjusting the effective focal length and the aperture number of the optical lens to meet the above conditional formula, the optical lens can obtain a large effective focal length while matching a smaller aperture number, so as to obtain the characteristics of a long focal length and a large aperture, enabling the optical lens to obtain sufficient light input, and further enabling the optical lens to obtain sufficient relative illumination when performing telephoto shooting, thereby improving the imaging quality of the optical lens.

[0061] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -0.9 < f2 / f < -0.5. By constraining the relationship between the focal length of the second lens and the effective focal length of the optical lens to meet the above conditional formula, and by utilizing the surface shape characteristics of the second lens, the aperture of the optical lens can be increased; at the same time, since the second lens is an aspherical lens, the aspherical order of the second lens can be controlled, reducing the surface shape complexity of the second lens, and further improving the aberration correction ability of the second lens for the light rays in the marginal field of view, increasing the relative illumination of the marginal field of view, so as to improve the imaging quality of the optical lens; it can also reduce the deflection degree of the light rays from the first lens, making the light ray trend stable, and effectively balancing the aberration brought by the first lens.

[0062] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens and the combined focal length f45 of the fourth lens and the fifth lens satisfy: -1 < f123 / f45 < -0.6. Satisfying the above conditional formula and reasonably distributing the refractive power of the entire optical assembly is beneficial to controlling the incident angle of light, so that the beam width is neither too large nor too small, the exit angle of the chief ray passing through the fourth lens and the fifth lens can be reduced, and the relative brightness of the imaging surface of the optical system can be increased; at the same time, it is beneficial to balance the tolerance sensitivity of each lens, and is also beneficial to reducing the total length of the optical imaging lens, improving the yield rate and miniaturization characteristics.

[0063] In some embodiments, the effective focal length f of the optical lens, the focal length f1 of the first lens, and the focal length f2 of the second lens satisfy: -7 < f / (f1 + f2) < -2.5. Satisfying the above conditional formula and reasonably controlling the relationship between the focal lengths of the first lens and the second lens and the effective focal length of the optical lens is beneficial to increasing the effective focal length of the optical lens.

[0064] In some embodiments, 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: 0.4 < (R3 + R4) / (R3 - R4) < 0.9. Satisfying the above conditional formula and controlling the ratio of the sum to the difference between the curvature radius of the object side surface and the curvature radius of the image side surface of the second lens can effectively control the refraction angle of the light beam on the second lens, so as to ensure the imaging quality of the camera lens and at the same time achieve good processing characteristics of the camera lens.

[0065] In some embodiments, the combined focal length f123 of the first lens, the second lens, and the third lens, the central thickness CT1 of the first lens, the central thickness CT2 of the second lens, and the central thickness CT3 of the third lens satisfy: 1.6 < f123 / (CT1 + CT2 + CT3) < 2.1. Satisfying the above conditional formula and controlling the relationship between the combined focal length of the first three lenses and the sum of the central thicknesses of the first three lenses can reduce the sensitivity of the first three lenses, eliminate chromatic aberration, spherical aberration, and coma of the optical imaging lens, and further achieve the purpose of reducing the aberration of the optical imaging lens. At the same time, it is also beneficial to the structural arrangement of the optical imaging lens, and further optimizes the process performance of the optical imaging lens and reduces the sensitivity of the lens.

[0066] In some embodiments, the entrance pupil diameter EPDI of the optical lens and the maximum clear aperture semi-diameter CSD_MAX among the first lens to the fifth lens satisfy: 1.7 < EPDI / CSD_MAX < 2.1. Satisfying the above conditional formula can effectively control the surface shape of the optical imaging lens, help correct field curvature, and improve imaging quality.

[0067] In some embodiments, the effective focal length f of the optical lens, the focal length f1 of the first lens, and the focal length f3 of the third lens satisfy: 7mm < f1×f3 / f < 18mm. By satisfying the above conditional formula and reasonably allocating f1, f3, and f, it is beneficial to reduce the field of view angle of the imaging lens and enable the imaging lens to better meet the requirements of telephoto shooting.

[0068] In some embodiments, the aperture value Fno of the optical lens satisfies: Fno ≤ 2.1. By satisfying the above conditional formula, while having good optical performance, it meets the design requirements of a large aperture and a long focal length.

[0069] In some embodiments, the central thickness CT1 of the first lens, the central thickness CT2 of the second lens, the central thickness CT4 of the fourth lens, and the central thickness CT5 of the fifth lens satisfy: 1.1 < (CT1 + CT2) / (CT4 + CT5) < 1.7. By satisfying the above conditional formula, the ratio of the central thicknesses of the front-end and rear-end lenses can be balanced, which is beneficial for lens assembly and improving the qualification rate.

[0070] In some embodiments, the effective focal length f of the optical lens and the image-side curvature radius R10 of the fifth lens satisfy: 0.6 < R10 / f < 2. By satisfying the above conditional formula, the angle of off-axis light incident on the image sensor can be suppressed, and it is beneficial for field adjustment.

[0071] In some embodiments, the edge thickness ET3 of the third lens and the edge thickness ET2 of the second lens satisfy: 0.65 < ET3 / ET2 < 1. By satisfying the above condition and reasonably configuring the edge thicknesses of the second lens and the third lens, the second lens and the third lens are easy to injection mold, which helps to improve the processability of the imaging system and can also ensure good imaging quality.

[0072] In some embodiments, the edge thickness ET5 of the fifth lens and the central thickness CT5 of the fifth lens satisfy: 0.9 < ET5 / CT5 < 1.1. By satisfying the above conditional formula, the overall thickness of the fifth lens is close, which can reasonably utilize the rear-end space of the optical system and reduce the manufacturing difficulty. Below the lower limit, the ratio of the edge thickness of the fifth lens is small, and it is difficult for the bearing part to reach the thickness standard; above the upper limit, the edge thickness of the fifth lens is too large, resulting in excessive occupation of space by the external bearing part.

[0073] In some embodiments, the sum ∑AT of the distances between any two adjacent lenses among the first lens to the fifth lens on the optical axis and the back focal length BFL of the optical lens satisfy: 0.6 < ∑AT / BFL < 0.9. By satisfying the above conditional formula, by effectively restricting the ratio of the sum of the distances between any two adjacent lenses among the first lens to the fifth lens on the optical axis to the distance between the image side of the fifth lens and the imaging surface on the optical axis, not only can the risk of stray light caused by the unreasonable size of the end of the lens group close to the imaging surface due to too small BFL be avoided, which is beneficial to balancing the aberration of the optical lens, but also the total length of the optical lens can be controlled.

[0074] In some embodiments, the sagittal height SAGX51 of the object-side clear aperture radius of the fifth lens and the sagittal height SAGX52 of the image-side clear aperture radius of the fifth lens satisfy: 0.7 < SAGX51 / SAGX52 < 1.3. By satisfying the above conditional formula, the surface shape difference between the object side and the image side of the fifth lens will not be too large, which is beneficial to reducing the tolerance sensitivity of the fifth lens, facilitating the processing and shaping of the lens, effectively eliminating the spherical aberration of the system, and obtaining a high-definition image.

[0075] In some embodiments, the distance AT4 between the fourth lens and the fifth lens on the optical axis, the central thickness CT3 of the third lens, the central thickness CT4 of the fourth lens, and the distance AT3 between the third lens and the fourth lens on the optical axis satisfy: 0.2 < AT4 / (CT3 + CT4 + AT3) < 0.4. By satisfying the above conditional formula, the interval distances of each lens on the optical axis are reasonably configured, which can effectively reduce the thickness sensitivity of the lens and help correct the field curvature.

[0076] In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: -0.3 < (f1 + f2) / (f1 - f2) < -0.1. By satisfying the above conditional formula, by reasonably distributing the optical power of the first lens and the second lens, it is beneficial to reducing the aberration of the marginal field of view.

[0077] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the fifth lens and the sum ∑AT of the distances between any two adjacent lenses among the first lens to the fifth lens on the optical axis satisfy: 2.8 < ∑CT / ∑AT < 3.5. By satisfying the above conditional formula, the lens distribution can be adjusted and a balance can be achieved between the lens thickness and the lens spacing, which helps to compress the volume.

[0078] In some embodiments, the optical lens satisfies the conditional formula: 10mm < f < 11.5mm, 30° < FOV < 40°, 10mm < TTL < 11.5mm, 6.5mm < IH < 8mm, where f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, TTL represents the total optical length of the optical lens, and IH represents the true image height corresponding to 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 long focal length and small total length, etc.

[0079] 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. On the other hand, when the lens material is glass, due to the low dispersion characteristic of the glass itself, the geometric chromatic aberration of the optical system can be effectively corrected. The optical lens provided by the present invention can adopt an all-plastic lens structure, which not only enables the lens to have excellent imaging performance, but also makes the structure of the lens relatively compact, and can better achieve the balance of miniaturization and high image quality of the lens.

[0080] In various embodiments of the present invention, when an aspherical lens is adopted, the shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0081] ;

[0082] where z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the conic coefficient, and B, C, D, E, F, G, H are the conic coefficients of the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth orders respectively.

[0083] The present invention will be further described in multiple embodiments below. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are partially different. For specific differences, please refer to the parameter tables of each embodiment. The following embodiments are only the preferred embodiments of the present invention, but the embodiments of the present invention are not limited only by the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing 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.

[0084] Embodiment 1

[0085] Please refer to Figure 1 , which shows a schematic structural diagram of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens sequentially includes, along the optical axis from the object side to the imaging surface: a diaphragm ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a filter G1.

[0086] The first lens L1 has positive refractive power, and its object side surface S1 and image side surface S2 are both convex surfaces;

[0087] The second lens L2 has negative refractive power, and its object-side surface S3 and image-side surface S4 are both concave;

[0088] The third lens L3 has positive refractive power, its object-side surface S5 is concave, and its image-side surface S6 is convex;

[0089] The fourth lens L4 has negative refractive power, its object-side surface S7 is concave, and its image-side surface S8 is convex;

[0090] The fifth lens L5 has negative refractive power, an object-side surface S9 thereof is convex at the near optical axis, and an image-side surface S10 thereof is concave at the near optical axis;

[0091] The object side surface S11 and the image side surface S12 of the filter G1 are both planes;

[0092] The imaging surface S13 is a plane.

[0093] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 are all plastic aspherical lenses.

[0094] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0095] Table 1-1

[0096]

[0097] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0098] Table 1-2

[0099]

[0100] In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 shown.

[0101] Figure 2 The astigmatism curve of Example 1 is shown, which represents the astigmatism 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 field angle (unit: °). It can be seen from the figure that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.05mm, indicating that the optical lens 100 can correct the astigmatism well.

[0102] Figure 3 The f~tan(θ) distortion curve of Example 1 is shown, which represents the f~tan(θ) distortion at different image heights on the imaging surface, the horizontal axis represents the f~tan(θ) distortion value (unit: %), and the vertical axis represents the field of view angle (unit: °). It can be seen from the figure that the f~tan(θ) distortion of the optical lens 100 is controlled within ±0.5%, indicating that the distortion of the optical lens 100 is well corrected.

[0103] Figure 4 The axial aberration curve of Example 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. It can be seen from the figure that the offset of the axial aberration is controlled within ±0.03mm, indicating that the optical lens 100 can correct the axial aberration well.

[0104] Figure 5 The vertical chromatic aberration curve of Example 1 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 chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the field angle. It can be seen from the figure that the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 100 can perfectly correct the chromatic aberration of each field of view.

[0105] Figure 6 The relative illumination curve of Example 1 is shown, which represents the relative illumination values ​​at different field angles on the imaging plane, with the horizontal axis representing the field angle (unit: °) and the vertical axis representing the relative illumination. It can be seen from the figure that the relative illumination value of the optical lens is still greater than 0.6 at the maximum half field angle, indicating that the optical lens 100 has a good relative illumination.

[0106] Example 2

[0107] See also Figure 7 , 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 convex at the near optical axis; the object side surface S9 of the fifth lens L5 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0108] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0109] Table 2-1

[0110]

[0111] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0112] Table 2-2

[0113]

[0114] In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 200 are shown as follows: Figure 8 , Fig. 9 , Fig.10 , Fig.11 and Fig.12 shown.

[0115] From Figure 8 It can be seen that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 200 can correct the astigmatism well.

[0116] from Fig. 9 It can be seen that the f~tan(θ) distortion of the optical lens 200 is controlled within ±0.5%, indicating that the distortion of the optical lens 200 is well corrected.

[0117] from Fig.10 It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 200 can correct the axial aberration well.

[0118] from Fig.11 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 200 can extremely well correct the chromatic aberration of each field of view.

[0119] from Fig.12 It can be seen that the relative illumination value of the optical lens is still greater than 0.7 at the maximum half field of view angle, indicating that the optical lens 200 has a very good relative illumination.

[0120] Example 3

[0121] See also Fig.13 , 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 convex at the near optical axis; the object side surface S9 of the fifth lens L5 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0122] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0123] Table 3-1

[0124]

[0125] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0126] Table 3-2

[0127]

[0128] In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 300 are shown as follows: Fig.14 , Fig.15 , Fig.16 , Fig.17 and Fig.18 shown.

[0129] from Fig.14 It can be seen that the astigmatism of the meridional image plane and the sagittal image plane is controlled within ±0.05 mm, indicating that the optical lens 300 can correct the astigmatism well.

[0130] from Fig.15 It can be seen that the f~tan(θ) distortion of the optical lens 300 is controlled within ±0.5%, indicating that the distortion of the optical lens 300 is well corrected.

[0131] from Fig.16 It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 300 can correct the axial aberration well.

[0132] from Fig.17 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1 μm, indicating that the optical lens 300 can extremely well correct the chromatic aberration of each field of view.

[0133] from Fig.18 It can be seen that the relative illumination value of the optical lens is still greater than 0.7 at the maximum half field of view angle, indicating that the optical lens 300 has a very good relative illumination.

[0134] Example 4

[0135] See also Fig.19 , shown is a schematic diagram of the structure of the optical lens 400 provided in Example 4 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 convex at the near optical axis; the object side surface S9 of the fifth lens L5 is concave; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0136] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0137] Table 4-1

[0138]

[0139] The surface parameters of the aspheric lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0140] Table 4-2

[0141]

[0142] In this embodiment, the astigmatism curve, f-tan (θ) distortion curve, axial aberration curve, vertical axis chromatic aberration curve, and relative illumination curve of the optical lens 400 are respectively as follows: Fig. 20 , Fig.21 , Fig. 22 , Fig.23 and Fig.24 shown.

[0143] from Fig. 20 It can be seen that the astigmatism of the meridian image plane and the sagittal image plane is controlled within ±0.05mm, indicating that the optical lens 400 can correct the astigmatism well.

[0144] from Fig.21 It can be seen that the f~tan(θ) distortion of the optical lens 400 is controlled within ±0.5%, indicating that the distortion of the optical lens 400 is well corrected.

[0145] from Fig. 22 It can be seen that the offset of the axial aberration is controlled within ±0.02 mm, indicating that the optical lens 400 can correct the axial aberration well.

[0146] from Fig.23 It can be seen that the vertical axis chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±1μm, indicating that the optical lens 400 can extremely well correct the chromatic aberration of each field of view.

[0147] from Fig.24 It can be seen that the relative illumination value of the optical lens is still greater than 0.8 at the maximum half field of view angle, indicating that the optical lens 400 has a very good relative illumination.

[0148] Please refer to Table 5, which shows the optical characteristics corresponding to the above embodiments, including the effective focal length f of the optical lens, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view angle, the chief ray incident angle CRA at the maximum image height, the maximum field of view angle FOV, and the numerical value corresponding to each conditional expression in each embodiment.

[0149] Table 5

[0150]

[0151] In summary, the optical lens provided by the present invention has at least the following advantages:

[0152] (1) Through the specific surface shape setting and reasonable optical focal length distribution, the lens has a telephoto characteristic, which can better present larger local details and make the picture more focused and compact, thus meeting the needs of local shooting; while effectively shortening the overall length of the optical lens, it also has a compact large aperture structure, so that the optical lens can obtain sufficient light input, and then the optical lens can obtain sufficient relative illumination when performing telephoto, thereby improving the imaging quality of the optical lens.

[0153] (2) The optical lens of the present invention can reasonably correct the overall aberration of the optical lens, so that the optical lens has small distortion and high illumination, thereby improving the imaging quality of the optical lens.

[0154] 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.

[0155] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, comprising five lenses, characterized in that: Along the optical axis from the object side to the imaging surface, it includes: A first lens having positive refractive power, whose object side surface and image side surface are both convex; The second lens has negative optical power, and both the object side surface and the image side surface are concave; A third lens element having positive refractive power and a convex image-side surface; a fourth lens having negative optical power, whose object side surface is concave and whose image side surface is convex; The fifth lens element has negative power and its image side surface is concave at the near optical axis; The effective focal length f of the optical lens and the aperture value Fno of the optical lens satisfy: 5mm <f / Fno<5.3mm。 2. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -0.9 <f2 / f<-0.5。 3. The optical lens according to claim 1, characterized in that: The combined focal length f123 of the first lens, the second lens and the third lens and the combined focal length f45 of the fourth lens and the fifth lens satisfy: <f123 / f45<-0.6。 4. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy: <f / (f1+f2)<-2.5。 5. The optical lens according to claim 1, characterized in that: A curvature radius R3 of the object side surface of the second lens and a curvature radius R4 of the image side surface of the second lens satisfy: 0.4<(R3+R4) / (R3-R4)<0.

9.

6. The optical lens according to claim 1, characterized in that: The combined focal length f123 of the first lens, the second lens and the third lens, the center thickness CT1 of the first lens, the center thickness CT2 of the second lens and the center thickness CT3 of the third lens satisfy: 1.6 <f123 / (CT1+CT2+CT3)<2.1。 7. The optical lens according to claim 1, characterized in that: The entrance pupil diameter EPDI of the optical lens and the largest semi-aperture diameter CSD_MAX of the first lens to the fifth lens satisfy: 1.7 <EPDI / CSD_MAX<2.1。 8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens, the focal length f1 of the first lens and the focal length f3 of the third lens satisfy: 7 mm <f1×f3 / f<18mm。 9. The optical lens according to claim 1, characterized in that: The aperture value Fno of the optical lens satisfies: Fno≤2.

1.

10. The optical lens according to claim 1, characterized in that: The center thickness CT1 of the first lens, the center thickness CT2 of the second lens, the center thickness CT4 of the fourth lens, and the center thickness CT5 of the fifth lens satisfy: 1.1<(CT1+CT2) / (CT4+CT5)<1.7.

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