Optical lens

Abstract

The utility model discloses an optical lens, and the optical lens sequentially comprises a first lens with focal power from an object side to an image side along an optical axis, a second lens with focal power, a third lens with focal power, a fourth lens with focal power, a fifth lens and a sixth lens from the object side to the image side, the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a convex surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface; the effective focal length F4 of the fourth lens and the center thickness d4 of the fourth lens on the optical axis meet the condition that F4 / d4 is larger than or equal to-8.8 and smaller than or equal to-6.21.

Description

Technical Field

[0001] This application relates to the field of optical components, and more specifically, to an optical lens. Background Technology

[0002] With the development of modern economic construction and management, enterprises and government agencies are paying increasing attention to video conferencing and access control, and are also placing higher demands on the cameras mounted on video conferencing and access control systems.

[0003] Current access control and video conferencing cameras on the market still have the following shortcomings:

[0004] 1. Existing lenses have significant distortion, which can still cause discomfort during use;

[0005] 2. Existing lens configurations are insufficient to effectively correct system aberrations, resulting in poor image quality.

[0006] 3. Existing lenses suffer from excessive overall length and large size, resulting in high overall cost and weight.

[0007] 4. Existing lenses, while meeting the requirements for low distortion, are usually large in size and have an excessively long overall length, making it difficult to simultaneously meet the requirements of both low distortion and miniaturization.

[0008] In conclusion, designing a compact, low-distortion, high-resolution, low-cost, and day-night cofocus prime lens to meet future market trends has become an urgent problem to be solved. Utility Model Content

[0009] This application provides an optical lens comprising, along the optical axis from the object side to the image side, the following in sequence: a first lens having optical power, wherein the object side is convex and the image side is concave; a second lens having optical power, wherein the object side is concave and the image side is convex; a third lens having positive optical power, wherein the object side is convex and the image side is convex; a fourth lens having negative optical power, wherein the object side is concave and the image side is convex; and a fifth lens having positive optical power, wherein the object side is convex and the image side is concave; wherein the effective focal length F4 of the fourth lens and the center thickness d4 of the fourth lens along the optical axis satisfy: -8.8≤F4 / d4≤-6.21.

[0010] In one embodiment, the radius of curvature R51 of the object side of the fifth lens, the radius of curvature R52 of the image side of the fifth lens, the effective focal length F5 of the fifth lens, the radius of curvature R41 of the object side of the fourth lens, the radius of curvature R42 of the image side of the fourth lens, and the effective focal length F4 of the fourth lens satisfy: 2.10≤(R51+R52)×F5 / (R41+R42)×F4≤5.12.

[0011] In one embodiment, the optical lens further includes a sixth lens disposed between the object side and the object side of the first lens, the image side of which is concave.

[0012] In one embodiment, the effective focal length F6 of the sixth lens and the radius of curvature R61 of the object side surface of the sixth lens satisfy: 0.7≤F6 / R61≤2.10.

[0013] In one embodiment, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -5.75≤F1 / F≤7.5.

[0014] In one embodiment, the combined effective focal length F12 of the first lens and the second lens, the radius of curvature R12 of the image side of the first lens and the radius of curvature R21 of the object side of the second lens satisfy: -2.5≤F12 / (R12+R21)≤7.00.

[0015] In one embodiment, the radius of curvature R22 of the image side of the second lens, the radius of curvature R31 of the object side of the third lens, and the radius of curvature R32 of the image side of the third lens satisfy: -8.5≤(R31+R32) / R22≤1.75.

[0016] In one embodiment, the Abbe number Vd3 of the third lens and the effective focal length F3 of the third lens satisfy: 17.78≤Vd3 / F3≤22.6.

[0017] In one embodiment, the radius of curvature R32 of the image side of the third lens, the radius of curvature R41 of the object side of the fourth lens, and the radius of curvature R42 of the image side of the fourth lens satisfy: 0.6≤R32 / (R41+R42)≤1.97.

[0018] In one embodiment, the effective focal length F4 of the fourth lens, the radius of curvature R41 of the object side of the fourth lens, and the radius of curvature R42 of the image side of the fourth lens satisfy: 1.22≤F4 / (R41+R42)≤2.22.

[0019] In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy: -1.15≤F4 / F5≤-0.75.

[0020] In one embodiment, the effective focal length F5 of the fifth lens and the total effective focal length F of the optical lens satisfy: 0.57≤F5 / F≤2.

[0021] In one embodiment, the axial distance SAG52 between the intersection of the image-side surface of the fifth lens and the optical axis to the inflection point of the image-side surface of the fifth lens and the axial distance SAGM between the intersection of the image-side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image-side surface of the fifth lens satisfy: -6≤SAG52 / SAGM≤3.72.

[0022] In one embodiment, the maximum value dmax of the center thickness of all lenses in the optical lens along the optical axis and the minimum value dmin of the center thickness of all lenses in the optical lens along the optical axis satisfy: 3.12≤dmax / dmin≤3.80.

[0023] In one embodiment, the center thickness d2 of the second lens on the optical axis, the center thickness d3 of the third lens on the optical axis, and the air gap CT23 of the second and third lenses on the optical axis satisfy: 26≤(d2+d3) / CT23≤40.

[0024] In one implementation, the total optical system length TTL of the optical lens and the total effective focal length F of the optical lens satisfy: 1.44≤TTL / F≤4.5.

[0025] In one embodiment, the total optical system length TTL of the optical lens and the distance BFL from the center of the image side of the fifth lens to the center of the imaging plane of the optical lens satisfy: 3.20≤TTL / BFL≤3.65.

[0026] In another aspect, this application provides an electronic device. This electronic device includes an optical lens according to this application and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

[0027] This application employs five or six lenses. By optimizing the shape, optical power, and related parameters of each lens, the optical lens achieves at least one beneficial effect, such as small size, low distortion, high resolution, low cost, and day and night confocal focus. Attached Figure Description

[0028] Other features, objects, and advantages of this utility application will become more apparent from the following detailed description of the embodiments, taken in conjunction with the accompanying drawings. In the drawings:

[0029] Figure 1 This is a schematic diagram illustrating the structure of an optical lens according to Embodiment 1 of this application;

[0030] Figure 2 To illustrate the distortion curve of the optical lens according to Embodiment 1 of this application;

[0031] Figure 3 To illustrate the structure of the optical lens according to Embodiment 2 of this application;

[0032] Figure 4 To illustrate the distortion curve of the optical lens according to Embodiment 2 of this application;

[0033] Figure 5 To illustrate the structure of the optical lens according to Embodiment 3 of this application;

[0034] Figure 6 To illustrate the distortion curve of the optical lens according to Embodiment 3 of this application;

[0035] Figure 7 This is a schematic diagram illustrating the structure of the optical lens according to Embodiment 4 of this application;

[0036] Figure 8 To illustrate the distortion curve of the optical lens according to Embodiment 4 of this application;

[0037] Figure 9 To illustrate the structural schematic diagram of the optical lens according to Embodiment 5 of this application; and

[0038] Figure 10 To illustrate the distortion curve of the optical lens according to Embodiment 5 of this application. Detailed Implementation

[0039] To facilitate understanding of this application, a more complete description of the application will be provided below with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of the application and are not intended to limit the scope of the 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.

[0040] 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 this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0041] 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.

[0042] 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 side is called the image-side surface of the lens.

[0043] 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.

[0044] 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 a meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0045] 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.

[0046] The features, principles and other aspects of this application are described in detail below.

[0047] In an exemplary embodiment, the optical lens includes, for example, five lenses with optical power, namely a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially along the optical axis from the object side to the image side.

[0048] In an exemplary embodiment, the optical lens includes, for example, six lenses with optical power, namely a sixth lens, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially along the optical axis from the object side to the image side.

[0049] In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the image side of the fifth lens. Optionally, the photosensitive element disposed on the image side of the ninth lens may be a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS).

[0050] In an exemplary embodiment, an aperture stop may be provided between the second and third lenses to limit the light beam and further improve the imaging quality of the optical lens. The aperture stop effectively concentrates the light entering the optical lens, reducing the maximum aperture of the optical lens and facilitating miniaturization. However, it should be noted that the location of the aperture stop disclosed herein is merely an example and not a limitation; in alternative embodiments, the aperture stop may be placed in other locations as needed.

[0051] In an exemplary embodiment, the sixth lens is placed between the object side and the object side of the first lens. The image side of the sixth lens is concave, which can converge incident light rays with a large field of view into the optical system as much as possible, effectively expanding the field of view and correcting optical distortion.

[0052] In an exemplary embodiment, the first lens has positive or negative optical power, with its object-side surface being convex and its image-side surface being concave. The convex-concave shape of the first lens can effectively control the trajectory of incident light in the optical system, reduce system aberrations, and improve image quality.

[0053] In an exemplary embodiment, the second lens has positive or negative optical power, with its object-side surface being concave and its image-side surface being convex. The concave-convex shape of the second lens helps to reduce the aperture height of the incident light, reduce system aberrations, and improve image quality.

[0054] In an exemplary embodiment, the third lens has positive optical power, and both its object-side and image-side surfaces are convex. This configuration of the third lens is beneficial for chromatic aberration correction and also helps to compensate for aberrations generated by the front lens of the optical system, reducing the pressure on the rear lens of the optical system to correct aberrations and improving the imaging quality of the optical system.

[0055] In an exemplary embodiment, the fourth lens has negative optical power, with a concave object side and a convex image side. This concave-convex shape of the fourth lens is symmetrical to the convex-concave shape of the first lens, which helps to balance various aberrations and improve image quality; it also effectively corrects optical distortion, making the absolute value of optical distortion less than 2.10%, reducing the degree of image distortion; at the same time, it effectively controls the optical path and elevates the light rays to meet the image size requirements.

[0056] In an exemplary embodiment, the fifth lens has positive optical power, with its object-side surface being convex and its image-side surface being concave. This configuration of the fifth lens effectively controls the direction of light rays, elevates the light rays to meet the image size requirements, and simultaneously corrects and compensates for optical distortions and various aberrations generated in front of the optical system, reducing the degree of image distortion and improving optical imaging performance.

[0057] In one embodiment, the optical lens according to this application satisfies: -8.8 ≤ F4 / d4 ≤ -6.21, where F4 is the effective focal length of the fourth lens and d4 is the center thickness of the fourth lens on the optical axis. Satisfying -8.8 ≤ F4 / d4 ≤ -6.21, and by rationally configuring the effective focal length and center thickness of the fourth lens on the optical axis, it is possible to help balance the optical distortion generated in the optical system, making the absolute value of optical distortion less than 2.10%, effectively reducing the degree of image distortion, and effectively restoring the realism of the photographed object.

[0058] In an exemplary embodiment, the optical lens according to this application satisfies: 2.10 ≤ (R51 + R52) × F5 / (R41 + R42) × F4 ≤ 5.12, where R51 is the radius of curvature of the object-side surface of the fifth lens, R52 is the radius of curvature of the image-side surface of the fifth lens, F5 is the effective focal length of the fifth lens, R41 is the radius of curvature of the object-side surface of the fourth lens, R42 is the radius of curvature of the image-side surface of the fourth lens, and F4 is the effective focal length of the fourth lens. Satisfying 2.10 ≤ (R51 + R52) × F5 / (R41 + R42) × F4 ≤ 5.12, and reasonably controlling the radii of curvature of the object-side and image-side surfaces of the fourth and fifth lenses, as well as the effective focal lengths of the fourth and fifth lenses, can effectively control the light path, reduce the deflection angle of the incident light from the fourth lens to the fifth lens, reduce tolerance sensitivity, and improve lens yield.

[0059] In an exemplary embodiment, the optical lens according to this application satisfies 0.7≤F6 / R61≤2.10, where F6 is the effective focal length of the sixth lens and R61 is the radius of curvature of the object-side surface of the sixth lens. Satisfying 0.7≤F6 / R61≤2.10, and rationally configuring the ratio of the effective focal length value of the sixth lens to the radius of curvature of the object-side surface of the sixth lens, is beneficial to balancing the optical distortion generated in the optical system, making the absolute value of optical distortion less than 2.10%, and at the same time, converging the incident light rays with a large field of view into the optical system as much as possible, effectively expanding the field of view.

[0060] In an exemplary embodiment, the optical lens according to this application satisfies: -5.75≤F1 / F≤7.5, where F1 is the effective focal length of the first lens and F is the total effective focal length of the optical lens. Satisfying -5.75≤F1 / F≤7.5 allows for a reasonable configuration of the effective focal length value of the first lens, controls the optical path direction, reduces the deflection angle of the incident and outgoing rays of the first lens, effectively reduces tolerance sensitivity over a large field of view, and simultaneously helps balance various aberrations, thereby improving the image quality of the lens.

[0061] In an exemplary embodiment, the optical lens according to this application satisfies: -2.5 ≤ F12 / (R12+R21) ≤ 7.00, where F12 is the combined effective focal length of the first and second lenses, R12 is the radius of curvature of the image-side surface of the first lens, and R21 is the radius of curvature of the object-side surface of the second lens. Satisfying -2.5 ≤ F12 / (R12+R21) ≤ 7.00 allows for a reasonable configuration of the shapes of the first and second lenses and the effective focal length of their combination, ensuring structural symmetry. This helps suppress astigmatism and effectively corrects various aberrations such as spherical aberration and coma, thereby improving the imaging quality of the optical system.

[0062] In an exemplary embodiment, the optical lens according to this application satisfies: -8.5 ≤ (R31 + R32) / R22 ≤ 1.75, where R22 is the radius of curvature of the image-side surface of the second lens, R31 is the radius of curvature of the object-side surface of the third lens, and R32 is the radius of curvature of the image-side surface of the third lens. By satisfying -8.5 ≤ (R31 + R32) / R22 ≤ 1.75, and by reasonably adjusting the radius of curvature of the image-side surface of the second lens, and the radius of curvature of the object-side surface and image-side surface of the third lens, the maximum light transmission can be effectively guaranteed, thereby improving the imaging brightness behind the optical system.

[0063] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 17.78 ≤ Vd3 / F3 ≤ 22.6, where Vd3 is the Abbe number of the third lens and F3 is the effective focal length of the third lens. Satisfying 17.78 ≤ Vd3 / F3 ≤ 22.6, and rationally configuring the ratio of the Abbe number to the effective focal length of the third lens, can effectively correct system chromatic aberration, improve the color saturation of the lens, and simultaneously ensure confocal focus for visible light and infrared light.

[0064] In an exemplary embodiment, the optical lens according to this application satisfies: 0.6 ≤ R32 / (R41+R42) ≤ 1.97, where R32 is the radius of curvature of the image-side surface of the third lens, R41 is the radius of curvature of the object-side surface of the fourth lens, and R42 is the radius of curvature of the image-side surface of the fourth lens. By satisfying 0.6 ≤ R32 / (R41+R42) ≤ 1.97 and by reasonably adjusting the shapes of the third and fourth lenses, the direction of the optical path can be effectively controlled, the light rays can be raised, and the imaging can meet the requirements of the target surface size.

[0065] In an exemplary embodiment, the optical lens according to this application satisfies: 1.22 ≤ F4 / (R41+R42) ≤ 2.22, where F4 is the effective focal length of the fourth lens, R41 is the radius of curvature of the object-side surface of the fourth lens, and R42 is the radius of curvature of the image-side surface of the fourth lens. Satisfying 1.22 ≤ F4 / (R41+R42) ≤ 2.22, by reasonably adjusting the effective focal length and shape of the fourth lens, ensures that the surface shape of the fourth lens is symmetrical with that of the first lens. This helps suppress astigmatism and effectively corrects various aberrations such as spherical aberration and coma, thereby improving the imaging quality of the optical system. Simultaneously, it effectively elevates the light rays, ensuring that the image meets the requirements of the target surface size.

[0066] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: -1.15 ≤ F4 / F5 ≤ -0.75, where F4 is the effective focal length of the fourth lens and F5 is the effective focal length of the fifth lens. By satisfying -1.15 ≤ F4 / F5 ≤ -0.75 and rationally configuring the effective focal length values ​​of the fourth and fifth lenses, optical distortion in the off-axis field of view can be effectively corrected, ensuring that the absolute value of optical distortion is less than 2.10%, effectively reducing the degree of image distortion and effectively restoring the realism of the photographed object.

[0067] In an exemplary embodiment, the optical lens according to this application satisfies: 0.57≤F5 / F≤2, where F5 is the effective focal length of the fifth lens and F is the total effective focal length of the optical lens. Satisfying 0.57≤F5 / F≤2, and reasonably configuring the effective focal length value of the fifth lens, helps to correct spherical aberration and coma generated in the front optical system, while balancing astigmatism and improving the imaging quality of the lens.

[0068] In an exemplary embodiment, the optical lens according to this application satisfies: -6 ≤ SAG52 / SAGM ≤ 3.72, where SAG52 is the axial distance between the intersection of the image-side surface of the fifth lens and the optical axis and the inflection point of the image-side surface of the fifth lens, and SAGM is the axial distance between the intersection of the image-side surface of the fifth lens and the optical axis and the vertex of the effective radius of the image-side surface of the fifth lens. Satisfying -6 ≤ SAG52 / SAGM ≤ 3.72, and reasonably adjusting the sag of the image-side surface of the fifth lens, can effectively enable the optical lens to have a large aperture in its wide field of view, ensuring maximum light transmission and contributing to improved illumination.

[0069] In an exemplary embodiment, the optical lens according to this application satisfies: 3.12 ≤ dmax / dmin ≤ 3.80, where dmax is the maximum value of the center thickness of all lenses in the optical lens along the optical axis, and dmin is the minimum value of the center thickness of all lenses in the optical lens along the optical axis. Satisfying 3.12 ≤ dmax / dmin ≤ 3.80 allows for reasonable control of the thickness of each lens, which is beneficial for stabilizing the function of each lens, minimizing changes in light trajectory under high and low temperatures, and enabling the lens to achieve heat-free operation.

[0070] In an exemplary embodiment, the optical lens according to this application satisfies: 26≤(d2+d3) / CT23≤40, where d2 is the center thickness of the second lens on the optical axis, d3 is the center thickness of the third lens on the optical axis, and CT23 is the air gap between the second and third lenses on the optical axis. By satisfying 26≤(d2+d3) / CT23≤40 and appropriately constraining the center thicknesses of the second and third lenses on the optical axis and the air gap between the second and third lenses on the optical axis, the total length of the optical system can be effectively reduced, making the total length TTL of the optical system ≤12mm.

[0071] In an exemplary embodiment, the optical lens according to this application satisfies the following condition: 1.44 ≤ TTL / F ≤ 4.5, where TTL is the total length of the optical system and F is the total effective focal length of the optical lens. Satisfying 1.44 ≤ TTL / F ≤ 4.5, under a given total effective focal length of the optical system, allows for a smaller total optical length by controlling the overall optical system length, which is beneficial for lens miniaturization, resulting in a total optical system length TTL ≤ 12mm.

[0072] In an exemplary embodiment, the optical lens according to this application satisfies: 3.20 ≤ TTL / BFL ≤ 3.65, where TTL is the total length of the optical system of the optical lens, and BFL is the distance from the center of the image-side surface of the fifth lens to the center of the imaging surface of the optical lens. Satisfying 3.20 ≤ TTL / BFL ≤ 3.65, with a fixed total optical system length, allows for increased assembly yield of the optical lens by reasonably controlling the optical back focal length. It also helps to reserve space for the installation of optical components, thereby increasing the design flexibility of the optical lens.

[0073] In an exemplary embodiment, the optical lens of this application has the characteristic of low distortion, with an absolute value of optical distortion of less than 2.10%.

[0074] In an exemplary embodiment, the optical lens of this application meets the miniaturization requirement, and the total length of the optical system is TTL≤12mm.

[0075] In an exemplary embodiment, the optical lens of this application may, as needed, include a filter and / or protective glass disposed between the fifth lens and the imaging surface to filter light of different wavelengths and prevent damage to the image-side elements (e.g., chips) of the optical lens.

[0076] In an exemplary embodiment, the optical lens according to this application can be made of a hybrid material of glass and plastic. This combination of glass and plastic is beneficial for reducing the cost of the optical system and for balancing the high and low temperature performance of the optical lens, achieving high image quality within the range of -40℃ to +80℃. Simultaneously, glass has a wider refractive index range than plastic, and using glass lenses is beneficial for correcting chromatic aberration in the optical system and improving the color saturation of the lens. Glass also has better temperature characteristics than plastic, which is beneficial for improving the reliability of the lens in high-temperature and high-humidity environments. This application does not specifically limit the number of lenses made of plastic and glass; if temperature performance is a primary concern, all lenses can be made of glass.

[0077] In an exemplary embodiment, the third lens may be made of glass, while the remaining lenses may be made of plastic. Using a glass-plastic hybrid design helps reduce the cost of the optical system and also helps balance the high and low temperature performance of the optical lens, achieving high image quality within the range of -40℃ to +80℃. Simultaneously, using glass lenses helps correct chromatic aberration in the optical system, improves the saturation of lens colors, and ensures confocal focus for visible and infrared light.

[0078] In exemplary embodiments, each lens in the optical lens can be a spherical lens or an aspherical lens. This application does not specifically limit the number of spherical and aspherical lenses; when image quality is a primary concern, the number of aspherical lenses can be increased, or even all lenses can be aspherical. An aspherical lens is characterized by a continuously changing curvature from its center to its periphery. Unlike a spherical lens, which has a constant curvature from its center to its periphery, an aspherical lens has better radius of curvature characteristics, offering advantages in improving distortion and astigmatism. Using aspherical lenses can minimize aberrations that occur during imaging, thereby improving the lens's image quality. Optionally, at least one of the object-side and image-side surfaces of each lens in the optical lens is an aspherical mirror. Optionally, the third lens in the optical lens is a spherical lens, while the object-side and image-side surfaces of the remaining lenses are aspherical mirrors.

[0079] The optical lens according to this application can use glass for the spherical lens and plastic for the aspherical lens. For example, the third lens can be a glass spherical lens, and the remaining lenses can be plastic aspherical lenses. This combination of spherical glass and aspherical plastic is beneficial for both reducing costs and improving the reliability of the lens in high temperature and high humidity environments.

[0080] The optical lens according to the above embodiments of this application can employ multiple lenses, such as the five or six lenses mentioned above. By rationally allocating the optical power, surface shape, and related parameters of each lens, the optical lens can achieve at least one beneficial effect, such as small size, low distortion, high resolution, low cost, and day / night confocal focus. However, those skilled in the art should understand that the number of lenses constituting the lens can be changed to obtain the various results and advantages described in this specification without departing from the technical solutions claimed in this application. For example, although five or six lenses are described as examples in the embodiments, the optical lens is not limited to including five or six lenses. If necessary, the optical lens may also include other numbers of lenses. Specific embodiments of the optical lens applicable to the above embodiments are further described below with reference to the accompanying drawings.

[0081] Example 1

[0082] The following is for reference Figure 1 An optical lens according to Embodiment 1 of this application is described. Figure 1 A schematic diagram of the structure of an optical lens according to Embodiment 1 of this application is shown.

[0083] like Figure 1 As shown, the optical lens includes, in sequence from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 along the optical axis.

[0084] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0085] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0086] The third lens L3 has positive optical power, and its object side S6 is convex, while its image side S7 is convex.

[0087] The fourth lens L4 has negative optical power, with its object side S8 being concave and its image side S9 being convex.

[0088] The fifth lens L5 has positive optical power, with its object side S10 being convex and its image side S11 being concave.

[0089] The optical lens may also include an aperture stop STO disposed between the second lens L2 and the third lens L3.

[0090] Optionally, the optical lens may also include a filter CG having an object-side surface S12 and an image-side surface S13 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color deviations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S13 and is finally imaged onto the imaging surface.

[0091] Table 1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 1, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0092]

[0093] Table 1

[0094] In this embodiment, the aperture number Fno of the optical lens is 2.10, the total length TTL of the optical system is 12mm, the maximum field of view (FOV) is 53.86°, and the absolute value of optical distortion is 1.93%.

[0095] In Example 1, the third lens is a glass spherical lens. The first, second, fourth, and fifth lenses are all plastic aspherical lenses, and the surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0096]

[0097] Where x is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 2 gives the higher-order coefficients A4, A6, A8, A11 that can be used for each aspherical mirror S1-S4, S8-S11 in Example 1. 10 A 12 A 14 and A 16 .

[0098] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -0.56 1.49E-03 1.09E-03 -1.00E-03 6.10E-04 -1.85E-04 2.84E-05 -1.69E-06 S2 -0.6 5.52E-03 -6.02E-03 3.27E-03 6.92E-03 -1.19E-02 6.61E-03 -1.33E-03 S3 -5.48 -2.17E-02 -1.19E-02 -2.83E-04 2.71E-02 -3.81E-02 2.04E-02 -4.00E-03 S4 4.51 -1.14E-02 1.65E-04 -1.06E-03 -1.54E-03 3.02E-03 -1.67E-03 3.09E-04 S8 -2.72 -3.55E-02 1.26E-02 2.93E-04 -1.05E-03 6.74E-05 6.49E-05 -1.07E-05 S9 -3.92 -2.53E-02 4.19E-03 2.61E-03 -1.17E-03 1.66E-04 -1.40E-06 -9.18E-07 S10 -5.54 -1.18E-02 2.66E-03 -1.36E-03 2.56E-04 -2.54E-05 -2.66E-07 9.04E-08 S11 -11.66 -8.86E-03 4.52E-04 -4.91E-04 1.06E-04 -1.38E-05 8.51E-07 -1.96E-08

[0099] Table 2

[0100] Figure 2 The distortion curve of the optical lens of Embodiment 1 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 2 It can be seen that the optical lens given in Example 1 can achieve good imaging quality.

[0101] Example 2

[0102] The following is for reference Figure 3 An optical lens according to Embodiment 2 of this application is described. In this embodiment and the following embodiments, for the sake of brevity, descriptions similar to those in Embodiment 1 will be omitted. Figure 3 A schematic diagram of the structure of an optical lens according to Embodiment 2 of this application is shown.

[0103] like Figure 3 As shown, the optical lens includes, in sequence from the object side to the image side, a sixth lens L6, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 along the optical axis.

[0104] The sixth lens L6 has positive optical power, with its object side S1 being convex and its image side S2 being concave.

[0105] The first lens L1 has negative optical power, its object side S3 is convex, and its image side S4 is concave.

[0106] The second lens L2 has negative optical power, with its object side S5 being concave and its image side S6 being convex.

[0107] The third lens L3 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0108] The fourth lens L4 has negative optical power, with its object side S10 being concave and its image side S11 being convex.

[0109] The fifth lens L5 has positive optical power, with its object side S12 being convex and its image side S13 being concave.

[0110] The optical lens may also include an aperture stop STO disposed between the second lens L2 and the third lens L3.

[0111] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0112] Table 3 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 2, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0113]

[0114] Table 3

[0115] In this embodiment, the aperture number Fno of the optical lens is 2.05, the total length TTL of the optical system is 12mm, the maximum field of view (FOV) is 58.26°, and the absolute value of optical distortion is 2.07%.

[0116] In Example 2, the third lens is a glass spherical lens. The sixth lens, the first lens, the second lens, the fourth lens, and the fifth lens are all plastic aspherical lenses. Table 4 shows the higher-order coefficients that can be used for each aspherical lens in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0117] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -26.4968 1.72E-02 -2.59E-03 5.80E-04 -6.42E-05 -2.63E-06 1.47E-06 -1.15E-07 S2 57.9983 1.06E-02 5.60E-03 -1.98E-03 9.06E-05 9.90E-05 -2.47E-05 1.67E-06 S3 -1.2735 -2.07E-02 7.81E-03 9.79E-04 -1.14E-03 -4.14E-06 1.22E-04 -2.21E-05 S4 -2.1086 3.44E-02 -8.55E-03 2.78E-02 -2.27E-02 -2.22E-03 1.65E-02 -7.46E-03 S5 -68.5309 -3.65E-02 1.39E-02 3.60E-02 -2.25E-02 -4.47E-02 5.67E-02 -1.87E-02 S6 -4.3542 1.25E-02 -5.46E-04 -7.86E-04 -1.15E-03 1.27E-03 -1.04E-03 2.29E-04 S10 -2.6403 4.91E-03 -6.93E-03 4.16E-03 -8.37E-04 -1.32E-04 7.44E-05 -8.95E-06 S11 -2.7298 3.83E-03 -2.85E-03 1.94E-03 -6.31E-04 1.29E-04 -1.52E-05 6.83E-07 S12 -5.9223 -1.62E-02 4.61E-03 -1.45E-03 2.62E-04 -2.57E-05 1.01E-06 -4.56E-09 S13 -15.1125 -1.24E-02 2.84E-03 -7.68E-04 1.04E-04 -5.64E-06 -1.75E-07 2.16E-08

[0118] Table 4

[0119] Figure 4 The distortion curve of the optical lens of Embodiment 2 is shown, representing the distortion magnitude corresponding to different image heights. According to... Figure 4 It can be seen that the optical lens given in Example 2 can achieve good imaging quality.

[0120] Example 3

[0121] The following is for reference Figure 5 An optical lens according to Embodiment 3 of this application is described. Figure 5 A schematic diagram of the structure of an optical lens according to Embodiment 3 of this application is shown.

[0122] like Figure 5 As shown, the optical lens includes, in sequence from the object side to the image side, a sixth lens L6, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 along the optical axis.

[0123] The sixth lens L6 has negative optical power, and its object side S1 is concave, and its image side S2 is concave.

[0124] The first lens L1 has positive optical power, with its object side S3 being convex and its image side S4 being concave.

[0125] The second lens L2 has positive optical power, with its object side S5 being concave and its image side S6 being convex.

[0126] The third lens L3 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0127] The fourth lens L4 has negative optical power, with its object side S10 being concave and its image side S11 being convex.

[0128] The fifth lens L5 has positive optical power, with its object side S12 being convex and its image side S13 being concave.

[0129] The optical lens may also include an aperture stop STO disposed between the second lens L2 and the third lens L3.

[0130] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0131] Table 5 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 3, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0132]

[0133] Table 5

[0134] In this embodiment, the aperture number Fno of the optical lens is 2.04, the total length TTL of the optical system is 11.42mm, the maximum field of view (FOV) is 98.84°, and the absolute value of optical distortion is 1.92%.

[0135] In Example 3, the third lens is a glass spherical lens. The sixth lens, the first lens, the second lens, the fourth lens, and the fifth lens are all plastic aspherical lenses. Table 6 shows the higher-order coefficients that can be used for each aspherical lens in Example 3, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0136] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -37.0991 2.38E-02 -3.50E-03 4.14E-04 -2.75E-05 -4.12E-07 1.95E-07 -9.15E-09 S2 1.8170 1.73E-03 8.70E-03 -1.69E-03 -3.63E-07 9.33E-05 -2.06E-05 -8.31E-07 S3 -1.3117 -1.21E-02 1.51E-02 3.65E-04 -1.36E-03 1.69E-04 1.70E-04 -5.84E-05 S4 -1.6507 6.22E-02 4.29E-03 4.63E-02 -2.80E-02 -4.14E-03 2.24E-02 -9.26E-03 S5 -24.8431 -2.75E-02 -1.16E-02 1.94E-02 1.26E-03 -3.92E-02 3.91E-02 -1.28E-02 S6 0.6787 1.06E-02 7.17E-04 -3.50E-04 2.83E-04 1.16E-03 -9.91E-04 2.65E-04 S10 -3.3037 4.67E-03 -7.45E-03 3.20E-03 -1.13E-03 -8.45E-05 1.07E-04 -1.56E-05 S11 -5.5089 1.31E-02 -3.84E-03 1.56E-03 -6.89E-04 1.36E-04 -1.31E-05 6.82E-07 S12 -5.3276 -1.90E-02 3.95E-03 -1.60E-03 2.84E-04 -2.50E-05 9.51E-07 9.96E-08 S13 -16.7186 -9.43E-03 2.23E-03 -8.14E-04 1.15E-04 -5.52E-06 2.61E-08 2.81E-08

[0137] Table 6

[0138] Figure 6 The distortion curve of the optical lens of Embodiment 3 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 6 It can be seen that the optical lens given in Example 3 can achieve good imaging quality.

[0139] Example 4

[0140] The following is for reference Figure 7 An optical lens according to Embodiment 4 of this application is described. Figure 7 A schematic diagram of the structure of an optical lens according to Embodiment 4 of this application is shown.

[0141] like Figure 7 As shown, the optical lens includes, in sequence from the object side to the image side, a sixth lens L6, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 along the optical axis.

[0142] The sixth lens L6 has negative optical power, and its object side S1 is concave, and its image side S2 is concave.

[0143] The first lens L1 has positive optical power, with its object side S3 being convex and its image side S4 being concave.

[0144] The second lens L2 has positive optical power, with its object side S5 being concave and its image side S6 being convex.

[0145] The third lens L3 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0146] The fourth lens L4 has negative optical power, with its object side S10 being concave and its image side S11 being convex.

[0147] The fifth lens L5 has positive optical power, with its object side S12 being convex and its image side S13 being concave.

[0148] The optical lens may also include an aperture stop STO disposed between the second lens L2 and the third lens L3.

[0149] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0150] Table 7 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 4, where the units for radius of curvature and thickness / distance are millimeters (mm).

[0151]

[0152]

[0153] Table 7

[0154] In this embodiment, the aperture number Fno of the optical lens is 2.05, the total length TTL of the optical system is 12mm, the maximum field of view (FOV) is 87.66°, and the absolute value of optical distortion is 1.99%.

[0155] In Example 4, the third lens is a glass spherical lens. The sixth lens, the first lens, the second lens, the fourth lens, and the fifth lens are all plastic aspherical lenses. Table 8 shows the higher-order coefficients that can be used for each aspherical lens in Example 4, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0156] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -54.1677 2.48E-02 -3.39E-03 4.13E-04 -2.78E-05 -3.59E-07 2.04E-07 -1.12E-08 S2 2.1542 9.44E-03 9.01E-03 -1.90E-03 8.85E-06 1.11E-04 -1.72E-05 -1.86E-06 S3 -1.4155 -1.37E-02 1.40E-02 4.47E-04 -1.40E-03 1.10E-04 1.65E-04 -5.41E-05 S4 -2.9467 5.31E-02 9.07E-03 2.15E-02 -2.17E-02 8.21E-04 1.63E-02 -1.05E-02 S5 -34.7973 -4.41E-02 -1.97E-03 2.18E-02 -1.98E-02 -3.61E-02 5.83E-02 -2.63E-02 S6 1.1293 1.30E-02 1.84E-03 2.61E-04 3.22E-04 1.13E-03 -1.12E-03 4.41E-04 S10 -3.0749 5.14E-03 -6.95E-03 3.44E-03 -9.29E-04 -9.53E-05 8.24E-05 -1.18E-05 S11 -3.5517 9.79E-03 -3.47E-03 1.84E-03 -6.55E-04 1.29E-04 -1.45E-05 7.10E-07 S12 -5.2602 -1.48E-02 4.31E-03 -1.57E-03 2.84E-04 -2.63E-05 6.68E-07 4.76E-08 S13 -10.4091 -7.93E-03 2.34E-03 -8.05E-04 1.11E-04 -6.44E-06 -1.16E-07 2.45E-08

[0157] Table 8

[0158] Figure 8 The distortion curve of the optical lens of Example 4 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 8 It can be seen that the optical lens given in Example 4 can achieve good imaging quality.

[0159] Example 5

[0160] The following is for reference Figure 9 An optical lens according to Embodiment 5 of this application is described. Figure 9 A schematic diagram of the structure of an optical lens according to Embodiment 5 of this application is shown.

[0161] like Figure 9 As shown, the optical lens includes, in sequence from the object side to the image side, a sixth lens L6, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 along the optical axis.

[0162] The sixth lens L6 has negative optical power, and its object side S1 is concave, and its image side S2 is concave.

[0163] The first lens L1 has positive optical power, with its object side S3 being convex and its image side S4 being concave.

[0164] The second lens L2 has positive optical power, with its object side S5 being concave and its image side S6 being convex.

[0165] The third lens L3 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0166] The fourth lens L4 has negative optical power, with its object side S10 being concave and its image side S11 being convex.

[0167] The fifth lens L5 has positive optical power, with its object side S12 being convex and its image side S13 being concave.

[0168] The optical lens may also include an aperture stop STO disposed between the second lens L2 and the third lens L3.

[0169] Optionally, the optical lens may also include a filter CG having an object-side surface S14 and an image-side surface S15 and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter CG and / or the protective glass can be used to correct color aberrations, and can also be used to protect the image sensor chip IMA located at the imaging surface. Light from the object passes sequentially through each surface S1 to S15 and is ultimately imaged onto the imaging surface.

[0170] Table 9 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 5, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0171]

[0172] Table 9

[0173] In this embodiment, the aperture number Fno of the optical lens is 1.81, the total length TTL of the optical system is 11.81 mm, the maximum field of view (FOV) is 87.16°, and the absolute value of optical distortion is 0.97%.

[0174] In Example 5, the third lens is a glass spherical lens. The sixth lens, the first lens, the second lens, the fourth lens, and the fifth lens are all plastic aspherical lenses. Table 10 shows the higher-order coefficients that can be used for each aspherical lens in Example 5, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0175] Face number k A4 A6 A8 A10 A12 A14 A16 S1 -25.4029 2.06E-02 -3.21E-03 4.12E-04 -2.88E-05 -3.87E-07 2.13E-07 -1.10E-08 S2 -44.0809 3.01E-02 2.34E-03 -1.65E-03 1.78E-04 7.02E-05 -3.38E-05 3.54E-06 S3 -1.2390 -1.13E-02 1.62E-02 -6.29E-04 -1.36E-03 1.97E-04 1.68E-04 -5.75E-05 S4 -2.8774 5.70E-02 1.54E-02 2.29E-02 -1.63E-02 1.49E-03 1.22E-02 -6.37E-03 S5 -30.2066 -3.98E-02 -3.45E-03 2.53E-02 -1.18E-02 -3.91E-02 5.22E-02 -1.92E-02 S6 0.9864 1.14E-02 2.30E-03 -4.71E-04 4.65E-04 1.29E-03 -1.20E-03 3.59E-04 S10 -2.5577 9.35E-03 -6.56E-03 3.74E-03 -7.83E-04 -1.12E-04 6.61E-05 -7.84E-06 S11 -3.2758 4.68E-03 -2.41E-03 2.03E-03 -6.56E-04 1.27E-04 -1.46E-05 6.87E-07 S12 -6.1814 -1.50E-02 4.25E-03 -1.56E-03 2.87E-04 -2.55E-05 7.42E-07 1.72E-08 S13 -70.0000 -6.83E-03 1.88E-03 -7.61E-04 1.18E-04 -6.72E-06 -2.15E-07 2.88E-08

[0176] Table 10

[0177] Figure 10 The distortion curve of the optical lens of Embodiment 5 is shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figure 10 It can be seen that the optical lens given in Example 5 can achieve good imaging quality.

[0178] In summary, Examples 1 to 5 respectively satisfy the relationships shown in Table 11 below.

[0179] Conditional Implementation Examples Example 1 Example 2 Example 3 Example 4 Example 5 0.7≤F6 / R61≤2.10 / 1.86 0.72 0.75 1.69 -5.75≤F1 / F≤7.5 -3.92 -2.21 4.45 3.92 7.09 -2.5≤F12 / (R12+R21)≤7.00 6.68 3.31 -1.60 -1.86 -1.89 -8.5≤(R31+R32) / R22≤1.75 0.17 -0.25 -4.63 -5.96 -7.78 17.78≤Vd³ / F³≤22.6 19.99 21.96 19.13 19.83 18.48 0.6≤R32 / (R41+R42)≤1.97 1.78 0.94 0.83 0.80 1.00 -8.8≤F4 / d4≤-6.21 -8.29 -8.32 -6.57 -7.61 -6.99 1.22≤F4 / (R41+R42)≤2.22 1.92 2.08 1.37 1.67 1.72 2.10≤(R51+R52)×F5 / (R41+R42)×F4≤5.12 3.20 2.97 2.53 2.27 4.65 -1.15≤F4 / F5≤-0.75 -0.96 -0.95 -0.79 -0.87 -0.97 0.57≤F5 / F≤2 0.78 1.09 1.79 1.61 1.25 -6≤SAG52 / SAGM≤3.72 -0.51 -1.30 1.04 1.40 -0.33 3.12≤dmax / dmin≤3.80 3.53 3.46 3.19 3.41 3.35 26≤(d2+d3) / CT23≤40 26.62 26.74 4.70 34.08 34.52 1.44≤TTL / F≤4.5 1.89 1.98 4.08 3.42 3.38 3.20≤TTL / BFL≤3.65 3.39 3.36 3.58 3.26 3.40

[0180] Table 11

[0181] This application also provides an electronic device that may include an optical lens according to the above embodiments of this application and an imaging element for converting an optical image formed by the optical lens into an electrical signal. The electronic device may be a stand-alone electronic device, such as a rangefinder camera, or an imaging module integrated into a rangefinder device. Furthermore, the electronic device may also be a stand-alone imaging device, such as an in-vehicle camera, or an imaging module integrated into a driver assistance system, such as a vehicle-mounted camera.

[0182] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical lens characterized in that, In an embodiment, the optical lens comprises, along an optical axis from an object side to an image side, in order: a first lens having optical power, the object side face of the first lens being convex, the image side face of the first lens being concave; a second lens having optical power, the object side face of the second lens being concave, the image side face of the second lens being convex; a third lens having positive optical power, the object side face of the third lens being convex, the image side face of the third lens being convex; a fourth lens having negative optical power, the object side face of the fourth lens being concave, the image side face of the fourth lens being convex; and a fifth lens having positive optical power, the object side face of the fifth lens being convex, the image side face of the fifth lens being concave. The effective focal length F4 of the fourth lens and the central thickness d4 of the fourth lens on the optical axis satisfy: -8.8 ≤ F4 / d4 ≤ -6.

21.

2. The optical lens of claim 1, wherein, The optical lens further comprises a sixth lens placed between the object side and the object side face of the first lens, the image side face of the sixth lens being concave.

3. The optical lens of claim 2, wherein, The effective focal length F6 of the sixth lens and the radius of curvature R61 of the object side face of the sixth lens satisfy: 0.7 ≤ F6 / R61 ≤ 2.

10.

4. The optical lens according to claim 1 or 2, characterized in that, The effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: -5.75 ≤ F1 / F ≤ 7.

5.

5. The optical lens of claim 1 or 2, wherein, The combined effective focal length F12 of the first lens and the second lens, the radius of curvature R12 of the image side face of the first lens and the radius of curvature R21 of the object side face of the second lens satisfy: -2.5 ≤ F12 / (R12+R21) ≤ 7.

00.

6. The optical lens of claim 1 or 2, wherein, The radius of curvature R22 of the image side face of the second lens, the radius of curvature R31 of the object side face of the third lens and the radius of curvature R32 of the image side face of the third lens satisfy: -8.5 ≤ (R31+R32) / R22 ≤ 1.

75.

7. The optical lens of claim 1 or 2, wherein, The Abbe number Vd3 of the third lens and the effective focal length F3 of the third lens satisfy: 17.78 ≤ Vd3 / F3 ≤ 22.

6.

8. The optical lens of claim 1 or 2, wherein, The radius of curvature R32 of the image side face of the third lens, the radius of curvature R41 of the object side face of the fourth lens and the radius of curvature R42 of the image side face of the fourth lens satisfy: 0.6 ≤ R32 / (R41+R42) ≤ 1.

97.

9. The optical lens of claim 1 or 2, wherein, The effective focal length F4 of the fourth lens, the radius of curvature R41 of the object side face of the fourth lens and the radius of curvature R42 of the image side face of the fourth lens satisfy: 1.22 ≤ F4 / (R41+R42) ≤ 2.

22.

10. The optical lens of claim 1 or 2, wherein, The effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy: -1.15 ≤ F4 / F5 ≤ -0.

75.

11. The optical lens of claim 1 or 2, wherein, The effective focal length F5 of the fifth lens and the total effective focal length F of the optical lens satisfy: 0.57 ≤ F5 / F ≤ 2.

12. The optical lens of claim 1 or 2, wherein, The on-axis distance SAG52 between the intersection of the image side face of the fifth lens and the optical axis and the inflexion point of the image side face of the fifth lens and the on-axis distance SAGM between the intersection of the image side face of the fifth lens and the optical axis and the effective radius vertex of the image side face of the fifth lens satisfy: -6 ≤ SAG52 / SAGM ≤ 3.

72.

13. The optical lens of claims 1 or 2, wherein, A maximum value dmax of the central thickness on the optical axis of all the lenses of the optical lens and a minimum value dmin of the central thickness on the optical axis of all the lenses of the optical lens satisfy: 3.12≤dmax / dmin≤3.

80.

14. The optical lens of claims 1 or 2, wherein, A central thickness d2 of the second lens on the optical axis, a central thickness d3 of the third lens on the optical axis, and an air interval CT23 of the second lens and the third lens on the optical axis satisfy: 26≤(d2+d3) / CT23≤40.

15. The optical lens of claims 1 or 2, wherein, An optical system total length TTL of the optical lens and a total effective focal length F of the optical lens satisfy: 1.44≤TTL / F≤4.

5.

16. The optical lens of claims 1 or 2, wherein, An optical system total length TTL of the optical lens and a distance BFL from a center of an image side surface of the fifth lens to a center of an imaging surface of the optical lens satisfy: 3.20≤TTL / BFL≤3.

65.

17. The optical lens of claims 1 or 2, wherein, A radius of curvature R51 of an object side surface of the fifth lens, a radius of curvature R52 of an image side surface of the fifth lens, an effective focal length F5 of the fifth lens, a radius of curvature R41 of an object side surface of the fourth lens, a radius of curvature R42 of an image side surface of the fourth lens, and an effective focal length F4 of the fourth lens satisfy: 2.10≤(R51+R52)×F5 / (R41+R42)×F4≤5.12.

Images