Optical lens

Abstract

The application discloses an optical lens which is composed of five lenses and sequentially comprises a diaphragm, a first lens with positive focal length, a second lens with negative focal length, a third lens with positive focal length, a fourth lens with positive focal length and a fifth lens with negative focal length from an object side to an imaging surface along an optical axis. The object side of the first lens is a convex surface, the object side and the image side of the second lens are both concave surfaces, the object side of the third lens is a convex surface, the image side of the third lens is a concave surface, the object side and the image side of the fourth lens are both convex surfaces, the object side of the fifth lens is a concave surface and the image side of the fifth lens is a convex surface. The optical lens satisfies a condition formula: 5 < f3 / f4 < 60, wherein f3 represents the focal length of the third lens and f4 represents the focal length of the fourth lens. The optical lens has the characteristics of long focal length and large image surface by reasonably setting the focal length and surface type of each lens, can realize the effects of background blurring and long-distance high-definition imaging, and can well meet the demand of telephoto.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging lenses, and particularly to an optical lens. Background Art

[0002] At present, with the popularization of portable electronic devices and the popularity of social, video, and live broadcast software, people's love for photography is increasing. Camera lenses have become a standard configuration of electronic devices, and even the primary consideration index for consumers when purchasing electronic devices.

[0003] With the continuous development of mobile information technology and the rapid development of electronic devices such as smart phones, tablets, and e-readers, the industry's requirements for the camera functions of electronic devices are also getting higher and higher. Camera lenses with various different characteristics can adapt to different application scenarios and meet different shooting needs. In recent years, as consumers' requirements for the photo-taking effects of electronic devices continue to increase, in addition to the demand for high pixels, they are more pursuing a sense of space during photo-taking, being able to highlight the subject. At this time, the advantages of telephoto lenses are revealed. Camera lenses with telephoto characteristics can capture distant scenes, effectively blur the background to highlight the subject, improve the imaging quality of distant scenes, and meet the telephoto requirements.

[0004] However, although the common five-piece optical lens already has good optical performance, it cannot well meet the design requirements of long focal length and large image plane, and the long-distance shooting effect is not good, affecting the shooting experience of users. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide an optical lens, which at least has the advantages of long focal length, large image plane, and high pixel.

[0006] The present invention realizes the above-mentioned invention purpose through the following technical solutions.

[0007] The present invention provides an optical lens, which is composed of five lenses, and successively includes along the optical axis from the object side to the imaging surface: an aperture stop; a first lens with a positive optical power, the object side surface of the first lens is a convex surface; a second lens with a negative optical power, both the object side surface and the image side surface of the second lens are concave surfaces; a third lens with a positive optical power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens with a positive optical power, both the object side surface and the image side surface of the fourth lens are convex surfaces; a fifth lens with a negative optical power, 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 optical lens satisfies the conditional formula: 5 < f3 / f4 < 60, where f3 represents the focal length of the third lens, and f4 represents the focal length of the fourth lens.

[0008] Compared with existing technologies, the optical lens provided by this invention uses five lenses with specific optical power. By reasonably matching the surface shapes and optical power distribution, the lens can achieve a large image area while having a long focal length, enabling background blurring and high-definition imaging at long distances, which can well meet the needs of telephoto. At the same time, by reasonably controlling the thickness of each lens and the distance between the lenses, the structure of the lens is more compact and has a smaller overall length. Attached Figure Description

[0009] 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:

[0010] Figure 1 This is a schematic diagram of the structure of an optical lens provided in the first embodiment of the present invention;

[0011] Figure 2 This is a field curvature curve diagram of the optical lens in the first embodiment of the present invention;

[0012] Figure 3 This is an optical distortion curve of the optical lens in the first embodiment of the present invention;

[0013] Figure 4 This is a chromatic aberration curve of the optical lens in the first embodiment of the present invention;

[0014] Figure 5 This is a schematic diagram of the structure of an optical lens provided in the second embodiment of the present invention;

[0015] Figure 6 This is a field curvature curve diagram of the optical lens in the second embodiment of the present invention;

[0016] Figure 7 This is an optical distortion curve of the optical lens in the second embodiment of the present invention;

[0017] Figure 8 This is a diagram showing the chromatic aberration curve of the optical lens in the second embodiment of the present invention.

[0018] Figure 9 This is a schematic diagram of the structure of an optical lens provided in the third embodiment of the present invention;

[0019] Figure 10 Here is a field curvature curve of the optical lens in the third embodiment of the present invention:

[0020] Figure 11 This is an optical distortion curve of the optical lens in the third embodiment of the present invention;

[0021] Figure 12 This is a diagram showing the transverse chromatic aberration curve of the optical lens in the third embodiment of the present invention;

[0022] Figure 13 This is a schematic diagram of the structure of an optical lens provided in the fourth embodiment of the present invention;

[0023] Figure 14 Here is a field curvature curve of the optical lens in the fourth embodiment of the present invention:

[0024] Figure 15 This is an optical distortion curve of the optical lens in the fourth embodiment of the present invention;

[0025] Figure 16 This is a chromatic aberration curve of the optical lens in the fourth embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present invention will be thorough and complete.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Throughout this specification, the same reference numerals refer to the same elements.

[0028] 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.

[0029] 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.

[0030] The present invention proposes an optical lens, which includes, in sequence along the optical axis from the object side to the imaging plane: an aperture stop, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a filter.

[0031] The first lens can have positive optical power and its object-side surface is convex; the second lens can have negative optical power and both its object-side and image-side surfaces are concave; the third lens can have positive optical power, its object-side surface is convex and its image-side surface is concave; the fourth lens can have positive optical power and both its object-side and image-side surfaces are convex; the fifth lens can have negative optical power, its object-side surface is concave and its image-side surface is convex. By rationally allocating the focal length and surface shape of the first to fifth lenses, the refraction angle of light can be effectively reduced, the optical difference sensitivity of each lens can be decreased, and the imaging quality of the optical system can be improved.

[0032] The optical lens provided by this invention uses five lenses with specific optical power. By reasonably matching the surface shapes and optical power distribution, the lens can achieve a large image area while having a long focal length, thus realizing the effects of background blur and high-definition imaging at long distances, which can well meet the needs of telephoto.

[0033] In some embodiments, the optical lens satisfies the following condition:

[0034] 5 <f3 / f4<60;

[0035] Where f3 represents the focal length of the third lens and f4 represents the focal length of the fourth lens. By satisfying the above conditions and reasonably controlling the optical power of the third and fourth lenses, the aberrations produced by the preceding lenses can be effectively balanced, improving the lens's resolution and enhancing the depth of field in the captured image.

[0036] In some embodiments, the optical lens satisfies the following condition:

[0037] 0.3 <f1 / f<0.6;

[0038] -0.2 <R11 / R12<0.2;

[0039] Where f1 represents the focal length of the first lens, f represents the effective focal length of the optical lens, R11 represents the radius of curvature of the object-side surface of the first lens, and R12 represents the radius of curvature of the image-side surface of the first lens. Meeting the above conditions can reduce the axial aberration of the system, which is beneficial for achieving high-definition effects in long-distance shooting and better realizing the telephoto characteristics.

[0040] In some embodiments, the optical lens satisfies the following condition:

[0041] -2 <f1 / f2<-1.1;

[0042] Where f1 represents the focal length of the first lens and f2 represents the focal length of the second lens. By satisfying the above conditions and reasonably setting the focal length ratio of the first and second lenses, the residual after balancing the negative spherical aberration generated by the first lens and the positive spherical aberration generated by the second lens can be controlled within a reasonable range, reducing the difficulty of correcting subsequent lens aberrations and improving the image quality of the lens near the optical axis.

[0043] In some embodiments, the optical lens satisfies the following condition:

[0044] -0.5 <f2 / f<-0.1;

[0045] -10 <R21 / R22<-1;

[0046] Where f2 represents the focal length of the second lens, f represents the effective focal length of the optical lens, R21 represents the radius of curvature of the object-side surface of the second lens, and R22 represents the radius of curvature of the image-side surface of the second lens. By satisfying the above conditions and setting the second lens as a biconcave negative lens, the refraction of light entering the second lens can be reduced, which is beneficial for correcting the optical distortion of the optical lens and improving the overall image quality.

[0047] In some embodiments, the optical lens satisfies the following condition:

[0048] 1 <f3 / f<30;

[0049] 0.8 <R31 / R32<1.3;

[0050] Where f3 represents the focal length of the third lens, f represents the effective focal length of the optical lens, R31 represents the radius of curvature of the object-side surface of the third lens, and R32 represents the radius of curvature of the image-side surface of the third lens. Satisfying the above conditions ensures that the third lens has suitable optical power and surface shape, which is beneficial for correcting field curvature and improving the resolving quality of the optical lens.

[0051] In some embodiments, the optical lens satisfies the following condition:

[0052] -0.1 <f2 / f3<0,

[0053] Where f2 represents the focal length of the second lens and f3 represents the focal length of the third lens. By satisfying the above range and reasonably allocating the focal length ratio of the second and third lenses, the aberrations of the system can be balanced, enabling the optical system to have high pixel imaging quality.

[0054] In some embodiments, the optical lens satisfies the following condition:

[0055] 0.3 <f4 / f<0.8;

[0056] -2 <R41 / R42<-0.2;

[0057] Where f4 represents the focal length of the fourth lens, f represents the effective focal length of the optical lens, R41 represents the radius of curvature of the object-side surface of the fourth lens, and R42 represents the radius of curvature of the image-side surface of the fourth lens. By satisfying the above ranges and reasonably controlling the optical power and surface shape of the fourth lens, it is beneficial to reduce the degree of light refraction within the fourth lens, decrease the sensitivity of the lens, and enable the lens to have good correction capabilities for higher-order aberrations, thereby better achieving a balance between telephoto capabilities and high pixel count.

[0058] In some embodiments, the optical lens satisfies the following condition:

[0059] -1.5 <f5 / f<-0.7;

[0060] 0.4 <R51 / R52<0.7;

[0061] Where f5 represents the focal length of the fifth lens, f represents the effective focal length of the optical lens, R51 represents the radius of curvature of the object-side surface of the fifth lens, and R52 represents the radius of curvature of the image-side surface of the fifth lens. Satisfying the above ranges allows the fifth lens to have suitable negative refractive power and surface shape, which is beneficial to increasing the incident angle of light on the imaging plane and better achieving the large image plane imaging effect of the lens.

[0062] In some embodiments, the optical lens satisfies the following condition:

[0063] -0.8 <f4 / f5<-0.3;

[0064] Where f4 represents the focal length of the fourth lens and f5 represents the focal length of the fifth lens. By satisfying the above range and appropriately matching the focal lengths of the fourth and fifth lenses, the aberrations produced by the positive and negative lenses can cancel each other out, thereby facilitating the correction of field curvature, astigmatism, and spherical aberration in optical lenses.

[0065] This helps to correct advanced aberrations of the optical lens and achieve high-pixel imaging.

[0066] In some embodiments, the optical lens satisfies the following condition:

[0067] 3 <f / IH<4;

[0068] FOV < 30°;

[0069] Where f represents the effective focal length of the optical lens, IH represents the actual half-image height of the optical lens on the imaging plane, and FOV represents the maximum field of view of the optical lens. By satisfying the above range and reasonably controlling the relationship between the effective focal length and image height of the lens, a better balance between the telephoto capability and the large image plane can be achieved. Thus, when shooting with the lens, while achieving background blur and long-distance imaging effects, high-definition image quality can also be guaranteed.

[0070] In some embodiments, the optical lens satisfies the following condition:

[0071] 0.45 <BFL / TTL<0.55;

[0072] Wherein, BFL represents the air gap on the optical axis between the image-side surface of the fifth lens and the imaging surface, and TTL represents the total optical length of the optical lens. By satisfying the above range and setting a larger optical back focal length, sufficient space can be provided for setting up a turning optical path in the optical system, thereby reducing the overall thickness of the lens.

[0073] Properly allocating the back focus of the optical system helps reduce the length of the optical system, while also reducing installation interference between the lens and the chip, thus improving the assembly yield.

[0074] In some embodiments, the optical lens satisfies the following condition:

[0075] 9mm < (f×IH) / f1 < 11mm;

[0076] Where f represents the effective focal length of the optical lens, IH represents the actual half-image height of the optical lens on the imaging plane, and f1 represents the focal length of the first lens. Meeting the above range, by reasonably controlling the value of (f×IH) / f1, is beneficial to obtaining a larger system focal length and a larger imaging plane. A larger imaging plane means potentially higher image resolution, allowing the lens to be matched with higher-pixel chips, achieving high-pixel imaging effects.

[0077] In some embodiments, the optical lens satisfies the following condition:

[0078] TTL / f < 1.0;

[0079] Where TTL represents the total optical length of the optical lens, and f represents the effective focal length of the optical lens. Meeting the above conditions ensures that the system achieves miniaturization while maintaining good imaging performance and realizing the characteristics of a large image plane.

[0080] In some implementations, the first lens, second lens, third lens, fourth lens, and fifth lens are all aspherical lenses. Using aspherical lenses can effectively correct aberrations, improve image quality, and provide optical performance products with higher cost-effectiveness.

[0081] In various embodiments of the present invention, when the lens in the optical lens is an aspherical lens, the surface shape of the aspherical lens satisfies the following equation:

[0082]

[0083] Where z is the sag of the aspherical surface at a height of h along the optical axis from the vertex of the aspherical surface, c is the paraxial curvature of the surface, k is the conic coefficient, and A 2i For the aspherical surface shape coefficient of the 2ith order.

[0084] 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.

[0085] First Embodiment

[0086] Please see Figure 1 The figure shown is a schematic diagram of the structure of the optical lens 100 provided in the first embodiment of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane S13, the following components in sequence: aperture ST, first lens L1, second lens L2, third lens L3, fourth lens L4, fifth lens L5 and filter G1.

[0087] Among them, the first lens L1 has positive optical power, its object side S1 is convex, and its image side S2 is concave.

[0088] The second lens L2 has negative optical power, its object side S3 is concave, and its image side S4 is concave.

[0089] The third lens L3 has positive optical power, its object side S5 is convex, and its image side S6 is concave.

[0090] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is convex.

[0091] The fifth lens L5 has negative optical power, its object-side surface S9 is concave, and its image-side surface S10 is convex; the object-side surface of the filter G1 is S11, and its image-side surface is S12.

[0092] 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.

[0093] The relevant parameters of each lens element in the optical lens 100 provided in the first embodiment of the present invention are shown in Table 1.

[0094] Table 1

[0095]

[0096] The surface shape coefficients of each aspherical surface of the optical lens 100 in this embodiment are shown in Table 2.

[0097] Table 2

[0098]

[0099]

[0100] In this embodiment, the field curvature curve, optical distortion curve, and lateral chromatic aberration diagram of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 and Figure 4 As shown.

[0101] Figure 2 The field curvature curve of the optical lens 100 in this embodiment is shown, which represents the curvature of the meridional image plane and the sagittal image plane. It can be seen from the figure that the field curvature of the image plane in both directions is controlled within ±0.10mm, indicating that the field curvature correction of the optical lens 100 is good.

[0102] Figure 3 The optical distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion at different image heights on the imaging plane. It can be seen from the figure that the optical distortion is controlled within ±1.5%, indicating that the distortion of the optical lens 100 is well corrected.

[0103] Figure 4 The transverse chromatic aberration curve of the optical lens 100 of this embodiment is shown, which represents the transverse chromatic aberration value between light of different wavelengths and the main wavelength. It can be seen from the figure that the transverse chromatic aberration value of each wavelength is within ±1.0μm, indicating that the transverse chromatic aberration of the optical lens 100 is well corrected.

[0104] Second Embodiment

[0105] Please see Figure 5 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in the second embodiment of the present invention. The optical lens 200 in this embodiment is roughly the same as that in the first embodiment, except that the curvature radius, lens thickness, and spacing of each lens surface are different.

[0106] Specifically, the relevant parameters of each lens element in the optical lens 200 of this embodiment are shown in Table 3.

[0107] Table 3

[0108]

[0109]

[0110] The surface coefficients of each aspherical surface of the optical lens 200 in this embodiment are shown in Table 4.

[0111] Table 4

[0112]

[0113] In this embodiment, the field curvature curve, optical distortion diagram, and transverse chromatic aberration diagram of the optical lens 200 are respectively as follows: Figure 6 , Figure 7 and Figure 8 As shown. From Figure 6 It can be seen that the field curvature of the meridional and sagittal image planes is controlled within ±0.10mm, indicating that the field curvature correction of the optical lens 200 is good. From Figure 7 This shows that optical distortion is controlled within ±1.5%, indicating that the distortion of the 200mm optical lens has been well corrected. Figure 8 It can be seen that the transverse chromatic difference values ​​of each wavelength are within ±1.5μm, indicating that the transverse chromatic difference of the optical lens 200 is well corrected.

[0114] Third Embodiment

[0115] Please see Figure 9 The diagram shows a structural schematic of the optical lens 300 provided in the third embodiment of the present invention. The optical lens 300 in this embodiment is generally the same as that in the first embodiment, with the main differences being that the image-side surface S2 of the first lens is convex near the optical axis, and the curvature radius, lens thickness, and spacing of each lens surface are different.

[0116] Specifically, the relevant parameters of each lens element in the optical lens 300 of this embodiment are shown in Table 5.

[0117] Table 5

[0118]

[0119]

[0120] The surface shape coefficients of each aspherical surface of the optical lens 300 in this embodiment are shown in Table 6.

[0121] Table 6

[0122]

[0123] In this embodiment, the field curvature curve, optical distortion diagram, and transverse chromatic aberration diagram of the optical lens 300 are respectively as follows: Figure 10 , Figure 11 and Figure 12 As shown. From Figure 10 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the field curvature correction of the 300mm optical lens is good. From Figure 11 As can be seen, optical distortion is controlled within ±1.5%, indicating that the distortion of the 300mm optical lens has been well corrected. From... Figure 12 It can be seen that the transverse chromatic difference values ​​of each wavelength are within ±1.0μm, indicating that the transverse chromatic difference of the optical lens 300 is well corrected.

[0124] Fourth embodiment

[0125] Please see Figure 13 The figure shows a schematic diagram of the structure of the optical lens 400 provided in the fourth embodiment of the present invention. The optical lens 400 in this embodiment is roughly the same as that in the first embodiment above. The main difference is that the curvature radius, lens thickness, and spacing of each lens surface are different.

[0126] Specifically, the relevant parameters of each lens element in the optical lens 400 of this embodiment are shown in Table 7.

[0127] Table 7

[0128]

[0129] The surface coefficients of each aspherical surface of the optical lens 400 in this embodiment are shown in Table 8.

[0130] Table 8

[0131]

[0132]

[0133] In this embodiment, the field curvature curve, optical distortion diagram, and transverse chromatic aberration diagram of the optical lens 400 are respectively as follows: Figure 14 , Figure 15 and Figure 16 As shown. From Figure 14 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the field curvature correction of the 400mm optical lens is good. From Figure 15 As can be seen, optical distortion is controlled within ±1.0%, indicating that the distortion of the 400mm optical lens has been well corrected. From... Figure 16It can be seen that the transverse chromatic difference values ​​of each wavelength are within ±1.0μm, indicating that the transverse chromatic difference of the optical lens 400 is well corrected.

[0134] Table 9 shows the optical characteristics corresponding to the four embodiments above, mainly including the system's effective focal length f, aperture number F#, total optical length TTL, maximum field of view FOV, and image height IH corresponding to half field of view, as well as the values ​​corresponding to each of the above conditional expressions.

[0135] Table 9

[0136]

[0137]

[0138] In summary, the optical lens provided by this invention employs five lenses with specific optical powers. By rationally combining the surface shapes and optical power distribution, it achieves a large image area while providing a long focal length, enabling background blurring and high-definition imaging at long distances, thus well meeting the needs of telephoto photography. Furthermore, by rationally controlling the thickness of each lens and the distance between them, the lens structure is relatively compact with a short overall length. Additionally, the rationally configured distance between the lenses eliminates the need for spacers, reducing the use of individual components, avoiding stray light from spacers, saving costs, and improving image quality.

[0139] 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.

[0140] 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 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 the present invention should be determined by the appended claims.

Claims

1. An optical lens consisting of five pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, successively comprises: a diaphragm; a first lens with positive refractive power, the object side surface of the first lens is convex; a second lens with negative refractive power, both the object side surface and the image side surface of the second lens are concave; a third lens with positive refractive power, the object side surface of the third lens is convex, and the image side surface of the third lens is concave; a fourth lens with positive refractive power, both the object side surface and the image side surface of the fourth lens are convex; a fifth lens with negative refractive power, the object side surface of the fifth lens is concave, and the image side surface of the fifth lens is convex; wherein the optical lens satisfies the conditional expression: 5 < f3 / f4 < 60, f3 represents the focal length of the third lens, and f4 represents the focal length of the fourth lens.

2. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: 0.3 < f1 / f < 0.6; -0.2 < R11 / R12 < 0.2; wherein f1 represents the focal length of the first lens, f represents the effective focal length of the optical lens, R11 represents the curvature radius of the object side surface of the first lens, and R12 represents the curvature radius of the image side surface of the first lens.

3. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: -2 < f1 / f2 < -1.1; wherein f1 represents the focal length of the first lens, and f2 represents the focal length of the second lens.

4. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: -0.5 < f2 / f < -0.1; -10 < R21 / R22 < -1; wherein f2 represents the focal length of the second lens, f represents the effective focal length of the optical lens, R21 represents the curvature radius of the object side surface of the second lens, and R22 represents the curvature radius of the image side surface of the second lens.

5. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: 1 < f3 / f < 30; 0.8 < R31 / R32 < 1.3; wherein f3 represents the focal length of the third lens, f represents the effective focal length of the optical lens, R31 represents the curvature radius of the object side surface of the third lens, and R32 represents the curvature radius of the image side surface of the third lens.

6. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: -0.1 < f2 / f3 < 0, wherein f2 represents the focal length of the second lens, and f3 represents the focal length of the third lens.

7. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: 0.3 < f4 / f < 0.8; -2 < R41 / R42 < -0.2; wherein f4 represents the focal length of the fourth lens, f represents the effective focal length of the optical lens, R41 represents the curvature radius of the object side surface of the fourth lens, and R42 represents the curvature radius of the image side surface of the fourth lens.

8. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: -1.5 < f5 / f < -0.7; 0.4 < R51 / R52 < 0.7; wherein f5 represents the focal length of the fifth lens, f represents the effective focal length of the optical lens, R51 represents the curvature radius of the object side surface of the fifth lens, and R52 represents the curvature radius of the image side surface of the fifth lens.

9. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: -0.8 < f4 / f5 < -0.3; Wherein f4 represents a focal length of the fourth lens, and f5 represents a focal length of the fifth lens.

10. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: 3 < f / IH < 4; Wherein f represents an effective focal length of the optical lens, and IH represents an actual half image height of the optical lens on an imaging plane.

11. The optical lens of claim 1, wherein, The optical lens satisfies the following conditional expression: 0.45 < BFL / TTL < 0.55; Wherein BFL represents an air distance on an optical axis from an image side surface of the fifth lens to the imaging plane, and TTL represents an optical total length of the optical lens.

Images