Optical lens

Abstract

The application discloses an optical lens. The optical lens comprises, in sequence from an object side to an image side along an optical axis, a first lens with negative focal power, the image side of which is concave; a second lens with negative focal power, the object side of which is concave, and the image side of which is convex; a third lens with positive focal power, the object side of which is convex, and the image side of which is concave; a fourth lens with positive focal power, both the object side and the image side of which are convex; a fifth lens with negative focal power, both the object side and the image side of which are concave; a sixth lens with positive focal power, both the object side and the image side of which are convex; and a seventh lens with positive focal power, the object side of which is convex, and the image side of which is concave; the distance TTL between the object side of the first lens and the imaging surface of the optical lens on the optical axis satisfies 5.1 <= TTL / F <= 6.0, wherein F is the effective focal length of the optical lens.

Description

Technical Field

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

[0002] Currently, fixed-focus lenses in the security field can be divided into large-aperture and small-aperture lenses, with large apertures having an FN0. of 1.0 and small apertures having an FN0. of 1.6 to 2.2. As people's requirements for image quality increase in daily applications, small-aperture lenses cannot meet the needs of higher-end applications; at the same time, because it is relatively difficult to balance optical aberrations in large-aperture lenses, they often need to use more glass and plastic lenses, which significantly increases the cost of the lens.

[0003] Therefore, in order to meet market demand, it is essential to develop a prime lens with an aperture close to that of a large aperture while maintaining a cost close to that of a small aperture. Summary of the Invention

[0004] This application provides an optical lens comprising, along the optical axis from the object side to the image side, the following components in sequence: a first lens with negative optical power, the image side of which is concave; a second lens with negative optical power, the object side of which is concave and the image side of which is convex; a third lens with positive optical power, the object side of which is convex and the image side of which is concave; a fourth lens with positive optical power, both the object side and the image side of which are convex; a fifth lens with negative optical power, both the object side and the image side of which are concave; a sixth lens with positive optical power, both the object side and the image side of which are convex; and a seventh lens with positive optical power, the object side of which is convex and the image side of which is concave; wherein the distance TTL from the object side of the first lens to the imaging plane of the optical lens on the optical axis satisfies the following condition: 5.1 ≤ TTL / F ≤ 6.0.

[0005] In one embodiment, the back focal length BFL of the optical lens and the distance TTL from the object side of the first lens to the imaging plane of the optical lens on the optical axis satisfy: 0.2≤BFL / TTL≤0.3.

[0006] In one embodiment, the effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: -1.9≤F1 / F≤-1.5.

[0007] In one embodiment, the on-axis distance ASG1 between the intersection of the object-side surface of the first lens and the optical axis and the vertex of the effective radius of the object-side surface of the first lens satisfies the optical half-aperture value D1S1 of the object-side surface of the first lens: -0.1≤ASG1 / D1S1≤0.2.

[0008] In one embodiment, the radius of curvature L2R1 of the object side surface of the second lens and the optical half-aperture value D2S1 of the object side surface of the second lens satisfy: -1.5≤L2R1 / D2S1≤-1.0.

[0009] In one embodiment, the refractive index ND2 of the second lens and the refractive index ND3 of the third lens satisfy: 1.5≤(ND2+ND3) / 2≤1.7.

[0010] In one embodiment, the effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: -47≤F2 / F≤-23.

[0011] In one embodiment, the effective focal length F3 of the third lens and the effective focal length F of the optical lens satisfy: 4.5≤F3 / F≤6.0.

[0012] In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy: 1.8≤F4 / F≤2.2.

[0013] In one implementation, the Abbe number VD4 of the fourth lens satisfies: 65 ≤ VD4 ≤ 96.

[0014] In one embodiment, the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: -1.3≤F5 / F6≤-0.8.

[0015] In one embodiment, the combined focal length F56 of the fifth and sixth lenses satisfies the following condition with respect to the effective focal length F of the optical lens: 5.4 ≤ F56 / F ≤ 17.

[0016] In one embodiment, the effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy: 7.4≤F7 / F≤14.5.

[0017] In one embodiment, the combined focal length F56 of the fifth and sixth lenses and the effective focal length F7 of the seventh lens satisfy: 0.3≤F56 / F7≤2.3.

[0018] In one embodiment, the center thickness D2 of the second lens on the optical axis and the center thickness D3 of the third lens on the optical axis satisfy: 0.3≤D3 / D2≤2.2.

[0019] In one embodiment, the center thickness D6 of the sixth lens on the optical axis and the center thickness D5 of the fifth lens on the optical axis satisfy: 1.8≤D6 / D5≤3.8.

[0020] In one embodiment, the optical lens further includes an aperture stop, the combined focal length Fb of all lenses on the image side of the aperture stop and the effective focal length F of the optical lens satisfying: 1.5≤Fb / F≤1.9.

[0021] In one embodiment, the optical lens further includes an aperture stop, the combined focal length Fa of all lenses on the object side of the aperture stop and the effective focal length F of the optical lens satisfying: -3.3≤Fa / Fb≤-1.0.

[0022] 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.

[0023] The optical lens provided in this application employs seven lenses. By optimizing the shape, optical power, and related parameters of each lens, the optical lens achieves at least one beneficial effect, such as large aperture (1.2≤FNO≤1.5), low cost, miniaturization (TTL≤22.5mm), day and night cofocus, and no blurring within a temperature range of -40℃ to 80℃. Attached Figure Description

[0024] 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:

[0025] Figure 1 This is a schematic diagram of the structure of an optical lens according to Embodiment 1 of this application;

[0026] Figure 2 This is a schematic diagram of the structure of an optical lens according to Embodiment 2 of this application;

[0027] Figure 3 This is a schematic diagram of the structure of an optical lens according to Embodiment 3 of this application; and

[0028] Figure 4 This is a schematic diagram of the structure of an optical lens according to Embodiment 4 of this application. Detailed Implementation

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] The features, principles and other aspects of this application are described in detail below.

[0037] In an exemplary embodiment, the optical lens includes, for example, seven lenses with optical power, namely a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. These seven lenses are arranged sequentially along the optical axis from the object side to the image side, and any two adjacent lenses among the first to seventh lenses may have a gap distance between them.

[0038] In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the image side of the seventh lens. Optionally, the photosensitive element disposed on the image side of the seventh lens may be a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS).

[0039] In an exemplary embodiment, the optical lens may further include an aperture stop for limiting the light beam, thereby further improving the imaging quality of the optical lens. Exemplarily, the aperture stop may be positioned between the second and third lenses, or between the third and fourth lenses. The aperture stop helps to concentrate the light entering the optical lens, reduce the maximum aperture of the optical lens, and decrease the assembly sensitivity of the system. However, it should be noted that the positions of the aperture stop disclosed herein are merely examples and not limitations; in alternative embodiments, the aperture stop may be positioned in other locations as needed.

[0040] In an exemplary embodiment, the first lens has negative optical power and its image side is concave, which can diffuse the large field of view light entering the optical system to the rear optical system, effectively increasing the amount of light transmitted and improving resolution.

[0041] In an exemplary embodiment, the second lens has negative optical power, with a concave object side and a convex image side. The second lens, in conjunction with the first lens, controls the light entering the optical system, reducing the sensitivity of the first lens.

[0042] In an exemplary embodiment, the third lens has positive optical power, with its object-side surface being convex and its image-side surface being concave. Because the third lens has positive optical power, when the aperture stop is positioned between the second and third lenses, the third lens is located next to the aperture stop, which can balance the aberrations caused by light passing through the aperture stop and ensure image quality.

[0043] In an exemplary embodiment, the fourth lens has positive optical power, and both its object-side and image-side surfaces are convex. The fourth lens can be combined with glass material to balance infrared performance in the system, achieving day-night confocal focusing and preventing defocusing at high and low temperatures.

[0044] In an exemplary embodiment, the fifth lens has negative optical power, and both its object-side and image-side surfaces are concave. The negative optical power of the fifth lens, combined with the rear positive lens, is used to balance the overall aberrations of the system and improve resolving power.

[0045] In an exemplary embodiment, the sixth lens has positive optical power, and both its object-side and image-side surfaces are convex. The sixth lens, with its positive optical power, is combined with the front negative lens to balance the overall aberrations of the system and improve resolving power.

[0046] In an exemplary embodiment, the seventh lens has positive optical power, with a convex object-side surface and a concave image-side surface. As the last lens in the system, the seventh lens can adjust the angle of the light rays at the end of the system, which is beneficial for optimizing CRA (Current Amplitude Reduction).

[0047] In an exemplary embodiment, the optical lens according to this application satisfies: 5.1 ≤ TTL / F ≤ 6.0, where TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging surface of the optical lens, and F is the effective focal length of the optical lens. Satisfying 5.1 ≤ TTL / F ≤ 6.0, under a certain system focal length value, by controlling the overall optical length of the system, the overall optical length of the system is made smaller, which is beneficial for miniaturization.

[0048] In an exemplary embodiment, the optical lens according to this application satisfies: 0.2 ≤ BFL / TTL ≤ 0.3, where BFL is the back focal length of the optical lens, and TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging surface of the optical lens. Satisfying 0.2 ≤ BFL / TTL ≤ 0.3 is beneficial for achieving miniaturization while ensuring the lens's assemblability by controlling the system's optical back focal length.

[0049] In an exemplary embodiment, the optical lens according to this application satisfies: -1.9 ≤ F1 / F ≤ -1.5, where F1 is the effective focal length of the first lens and F is the effective focal length of the optical lens. Satisfying -1.9 ≤ F1 / F ≤ -1.5, by converging the incident light rays, the large field of view light entering the optical system is diverged to the rear optical system, which can effectively increase the light transmission and improve the resolution.

[0050] In an exemplary embodiment, the optical lens according to this application satisfies: -0.1≤ASG1 / D1S1≤0.2, where ASG1 is the axial distance between the intersection of the object-side surface of the first lens and the optical axis and the vertex of the effective radius of the object-side surface of the first lens, and D1S1 is the optical half-aperture value of the object-side surface of the first lens. Satisfying -0.1≤ASG1 / D1S1≤0.2, by controlling the sag of the object-side surface of the first lens, makes the object-side surface of the first lens smooth, which helps to reduce the ghosting risk of the first lens, and also helps to reduce the ghosting risk of the protective glass placed in front of the photosensitive chip of the optical lens.

[0051] In an exemplary embodiment, the optical lens according to this application satisfies: -1.5 ≤ L2R1 / D2S1 ≤ -1.0, where L2R1 is the radius of curvature of the object-side surface of the second lens, and D2S1 is the optical half-aperture value of the object-side surface of the second lens. Satisfying -1.5 ≤ L2R1 / D2S1 ≤ -1.0, by controlling the radius of curvature of the object-side surface of the second lens, ensures that the curvature of the second lens is within a certain range. This helps eliminate the ghosting risk of the second lens and also helps eliminate the ghosting of the protective glass placed in front of the photosensitive chip of the optical lens.

[0052] In an exemplary embodiment, the optical lens according to this application satisfies: 1.5 ≤ (ND2 + ND3) / 2 ≤ 1.7, where ND2 is the refractive index of the second lens and ND3 is the refractive index of the third lens. Satisfying 1.5 ≤ (ND2 + ND3) / 2 ≤ 1.7, by controlling the refractive index of the second or third lens, can balance the aberrations generated by light passing through the aperture stop, which is beneficial for improving resolution.

[0053] In an exemplary embodiment, the optical lens according to this application satisfies: -47≤F2 / F≤-23, where F2 is the effective focal length of the second lens and F is the effective focal length of the optical lens. Satisfying -47≤F2 / F≤-23 further diverges the light, helps to smooth the light transition, and reduces the sensitivity of the first lens.

[0054] In an exemplary embodiment, the optical lens according to this application satisfies: 4.5 ≤ F3 / F ≤ 6.0, where F3 is the effective focal length of the third lens and F is the effective focal length of the optical lens. Satisfying 4.5 ≤ F3 / F ≤ 6.0 helps to balance the aberrations caused by light passing through the aperture stop and ensures image quality.

[0055] In an exemplary embodiment, the optical lens according to this application satisfies: 1.8 ≤ F4 / F ≤ 2.2, where F4 is the effective focal length of the fourth lens and F is the effective focal length of the optical lens. Satisfying 1.8 ≤ F4 / F ≤ 2.2 is beneficial for maintaining a stable effective focal length over a wide temperature range, exhibiting excellent temperature performance, and helping the optical lens maintain stable performance under temperature changes.

[0056] In an exemplary embodiment, the optical lens according to this application satisfies: 65≤VD4≤96, where VD4 is the Abbe number of the fourth lens. Satisfying 65≤VD4≤96, by controlling the Abbe number of the fourth lens, is beneficial for balancing infrared band performance, enabling imaging in the infrared band and achieving day and night confocal focusing.

[0057] In an exemplary embodiment, the optical lens according to this application satisfies: -1.3≤F5 / F6≤-0.8, where F5 is the effective focal length of the fifth lens and F6 is the effective focal length of the sixth lens. Satisfying -1.3≤F5 / F6≤-0.8, through the combination of positive and negative lenses of the fifth and sixth lenses, helps to balance high and low temperature performance and improve the system's resolution.

[0058] In an exemplary embodiment, the fifth lens and the sixth lens may form a cemented lens.

[0059] In an exemplary embodiment, the optical lens according to this application satisfies: 5.4 ≤ F56 / F ≤ 17, where F56 is the combined focal length of the fifth and sixth lenses, and F is the effective focal length of the optical lens. Satisfying 5.4 ≤ F56 / F ≤ 17, through the combination of the positive and negative lenses of the fifth and sixth lenses, reduces or eliminates the sensitive air gap, which helps to reduce tolerance sensitivity and improve production yield.

[0060] In an exemplary embodiment, the optical lens according to this application satisfies: 7.4 ≤ F7 / F ≤ 14.5, where F7 is the effective focal length of the seventh lens and F is the effective focal length of the optical lens. Satisfying 7.4 ≤ F7 / F ≤ 14.5, and controlling the optical path through the last lens of the system, is beneficial for improving the system's resolution and reducing CRA.

[0061] In an exemplary embodiment, the optical lens according to this application satisfies: 0.3 ≤ F56 / F7 ≤ 2.3, where F56 is the combined focal length of the fifth and sixth lenses, and F7 is the effective focal length of the seventh lens. Satisfying 0.3 ≤ F56 / F7 ≤ 2.3, by controlling the focal length ratio of the last three lenses, helps to reduce system astigmatism and improve resolution.

[0062] In an exemplary embodiment, the optical lens according to this application satisfies: 0.3 ≤ D3 / D2 ≤ 2.2, where D2 is the center thickness of the second lens on the optical axis, and D3 is the center thickness of the third lens on the optical axis. Satisfying 0.3 ≤ D3 / D2 ≤ 2.2, by reasonably controlling the center thicknesses of the second and third lenses on the optical axis, helps to reduce system field curvature and ensure image quality.

[0063] In an exemplary embodiment, the optical lens according to this application satisfies: 1.8 ≤ D6 / D5 ≤ 3.8, where D6 is the center thickness of the sixth lens on the optical axis, and D5 is the center thickness of the fifth lens on the optical axis. Satisfying 1.8 ≤ D6 / D5 ≤ 3.8, by reasonably controlling the center thicknesses of the sixth and fifth lenses on the optical axis, helps to reduce system spherical aberration and ensure image quality.

[0064] In an exemplary embodiment, the optical lens according to this application satisfies: 1.5 ≤ Fb / F ≤ 1.9, where Fb is the combined focal length of all lenses on the image side of the aperture stop, and F is the effective focal length of the optical lens. Satisfying 1.5 ≤ Fb / F ≤ 1.9 reduces optical aberrations converging onto the receiving chip by controlling the focal length value at the system backend, which is beneficial for clear imaging.

[0065] In an exemplary embodiment, the optical lens according to this application satisfies: -3.3 ≤ Fa / Fb ≤ -1.0, where Fa is the combined focal length of all lenses on the object side of the aperture stop, and F is the effective focal length of the optical lens. Satisfying -3.3 ≤ Fa / Fb ≤ -1.0, by reasonably allocating the focal length values ​​of the front and rear parts of the aperture stop, helps to reduce the performance difference between the front and rear ends and ensures the stability of the system.

[0066] In an exemplary embodiment, the optical lens of this application may be made of a glass-plastic hybrid material. For example, a glass-plastic hybrid material consisting of one glass lens and six plastic lenses may be used. This is beneficial for reducing the cost of the optical system and for balancing the high and low temperature performance of the optical lens, ensuring high imaging quality within the range of -40℃ to +80℃.

[0067] In an exemplary embodiment, the aperture number FNO of the optical lens of this application satisfies: 1.2≤FNO≤1.5, which ensures that the optical lens has a large light transmission and clear imaging.

[0068] In an exemplary embodiment, the distance TTL between the object side of the first lens of the optical lens and the imaging surface of the optical lens on the optical axis satisfies the following: TTL≤22.5mm, short total optical length, compact structure, which is conducive to miniaturization.

[0069] In an exemplary embodiment, the optical lens of this application may, as needed, include a filter and / or protective glass disposed between the seventh 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.

[0070] In an exemplary embodiment, the first to seventh lenses can be spherical lenses or aspherical lenses. 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, and 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 of the first to seventh lenses is an aspherical mirror. Optionally, the object-side and image-side surfaces of each of the first, second, third, fifth, sixth, and seventh lenses are both aspherical mirrors, while the object-side and image-side surfaces of the fourth lens are spherical mirrors.

[0071] The optical lens according to the above embodiments of this application may employ multiple lenses, such as the seven lenses described above. However, those skilled in the art should understand that the number of lenses constituting the lens can be changed without departing from the technical solutions claimed in this application to obtain the various results and advantages described in this specification. For example, although seven lenses are described as an example in the embodiments, the optical lens is not limited to including seven 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.

[0072] Example 1

[0073] 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.

[0074] 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, a fifth lens L5, a sixth lens L6, and a seventh lens L7 along the optical axis.

[0075] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0076] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0077] The third lens L3 has positive optical power, with its object side S6 being convex and its image side S7 being concave.

[0078] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0079] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0080] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0081] The seventh lens L7 has positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being concave.

[0082] The optical lens may also include an aperture stop STO, which may be positioned between the second lens L2 and the third lens L3 to improve image quality.

[0083] Optionally, the optical lens may also include a filter PB having an object-side surface S16 and an image-side surface S17, and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter PB 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 S18. Light from the object passes sequentially through surfaces S1 to S17 and is finally imaged onto the imaging surface S18.

[0084] 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).

[0085]

[0086] Table 1

[0087] In Example 1, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, sixth, and seventh lenses are aspherical. The surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0088]

[0089] Where x is the distance vector from the vertex of the aspherical surface at a height 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, A1, A2, A3, A4, A5, A6, A8, A9, A1, A1, A1, A2 ... 10 A 12 and A 14 .

[0090]

[0091]

[0092] Table 2

[0093] Example 2

[0094] The following is for reference Figure 2 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 2 A schematic diagram of the structure of an optical lens according to Embodiment 2 of this application is shown.

[0095] like Figure 2 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, a fifth lens L5, a sixth lens L6, and a seventh lens L7 along the optical axis.

[0096] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0097] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0098] The third lens L3 has positive optical power, with its object side S5 being convex and its image side S6 being concave.

[0099] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0100] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0101] The sixth lens L6 has positive optical power, and its object side S12 is convex, and its image side S13 is convex.

[0102] The seventh lens L7 has positive optical power, with its object-side surface S14 being convex and its image-side surface S15 being concave.

[0103] The optical lens may also include an aperture stop STO, which may be positioned between the third lens L3 and the fourth lens L4 to improve image quality.

[0104] Optionally, the optical lens may also include a filter PB having an object-side surface S16 and an image-side surface S17, and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter PB 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 S18. Light from the object passes sequentially through surfaces S1 to S17 and is finally imaged onto the imaging surface S18.

[0105] 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).

[0106]

[0107]

[0108] Table 3

[0109] In Example 2, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, sixth, and seventh lenses are aspherical. Table 4 shows the higher-order coefficients that can be used for each aspherical mirror in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0110] Face number k A4 A6 A8 A10 A12 A14 S1 27.07 -1.44E-03 1.85E-04 -1.69E-05 6.75E-07 -1.09E-08 0.00E+00 S2 -0.26 -3.12E-04 5.08E-04 -1.22E-04 2.57E-05 -2.23E-06 0.00E+00 S3 -0.44 5.15E-03 1.59E-04 -3.83E-05 7.83E-06 -1.01E-06 0.00E+00 S4 -0.28 3.70E-03 4.15E-05 5.57E-06 -1.91E-06 3.22E-08 0.00E+00 S5 1.81 3.67E-04 4.28E-05 1.52E-06 -3.20E-07 4.44E-09 0.00E+00 S6 -50.00 -2.27E-04 1.06E-04 3.39E-06 2.39E-07 -4.57E-08 0.00E+00 S10 5.54 -5.62E-03 4.26E-04 -1.81E-07 -1.83E-06 6.84E-08 0.00E+00 S11 -5.42 -1.37E-03 1.25E-04 2.12E-06 -1.29E-07 -3.62E-08 0.00E+00 S12 2.02 9.68E-05 -1.70E-04 4.86E-06 2.33E-07 -3.09E-08 0.00E+00 S13 -3.90 -1.54E-03 1.37E-04 -7.60E-06 -6.84E-07 6.49E-08 0.00E+00 S14 -1.33 1.10E-04 -3.09E-05 -1.36E-06 2.30E-08 0.00E+00 0.00E+00 S15 -44.43 -5.79E-04 5.45E-05 2.38E-06 -3.04E-07 0.00E+00 0.00E+00

[0111] Table 4

[0112] Example 3

[0113] The following is for reference Figure 3 An optical lens according to Embodiment 3 of this application is described. Figure 3 A schematic diagram of the structure of an optical lens according to Embodiment 3 of this application is shown.

[0114] like Figure 3 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, a fifth lens L5, a sixth lens L6, and a seventh lens L7 along the optical axis.

[0115] The first lens L1 has negative optical power, with its object side S1 being convex and its image side S2 being concave.

[0116] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0117] The third lens L3 has positive optical power, with its object side S5 being convex and its image side S6 being concave.

[0118] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0119] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0120] The sixth lens L6 has positive optical power, and its object side S11 is convex, and its image side S12 is convex.

[0121] The seventh lens L7 has positive optical power, with its object side S13 being convex and its image side S14 being concave.

[0122] The optical lens may also include an aperture stop STO, which can be positioned between the third lens L3 and the fourth lens L4 to improve image quality. The fifth lens L5 and the sixth lens L6 form a cemented lens.

[0123] Optionally, the optical lens may also include a filter PB having an object-side surface S15 and an image-side surface S16, and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter PB 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 S17. Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto the imaging surface S17.

[0124] 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).

[0125]

[0126] Table 5

[0127] In Example 3, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, sixth, and seventh lenses are aspherical. Table 6 shows the higher-order coefficients that can be used for each aspherical mirror in Example 3, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0128] Face number k A4 A6 A8 A10 A12 A14 S1 45.40 -1.26E-03 2.06E-04 -1.36E-05 3.24E-07 0.00E+00 0.00E+00 S2 -0.08 -2.57E-03 8.22E-04 -1.57E-04 2.39E-05 -1.69E-06 0.00E+00 S3 -0.41 5.05E-03 1.87E-04 -4.46E-05 6.00E-06 -7.05E-07 0.00E+00 S4 -0.35 4.19E-03 6.70E-05 2.95E-06 -2.52E-06 1.17E-07 0.00E+00 S5 0.41 2.93E-05 2.42E-05 1.98E-06 -2.59E-07 -2.02E-09 0.00E+00 S6 -50.01 -8.62E-04 1.48E-04 8.22E-07 -3.33E-07 -1.69E-08 0.00E+00 S10 -1.94 -4.05E-03 2.88E-04 -8.42E-06 -1.11E-06 4.07E-08 0.00E+00 S11 -50.00 -3.74E-03 2.16E-04 1.13E-05 -1.46E-06 -5.80E-09 0.00E+00 S12 -3.80 -1.77E-03 1.29E-04 -7.11E-06 -7.47E-07 4.68E-08 0.00E+00 S13 1.93 3.02E-04 -1.74E-05 -2.44E-06 -1.47E-07 0.00E+00 0.00E+00 S14 -21.39 -6.75E-04 8.95E-05 1.61E-07 -6.85E-08 0.00E+00 0.00E+00

[0129] Table 6

[0130] Example 4

[0131] The following is for reference Figure 4 An optical lens according to Embodiment 4 of this application is described. Figure 4A schematic diagram of the structure of an optical lens according to Embodiment 4 of this application is shown.

[0132] like Figure 4 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, a fifth lens L5, a sixth lens L6, and a seventh lens L7 along the optical axis.

[0133] The first lens L1 has negative optical power, and its object side S1 is concave, and its image side S2 is concave.

[0134] The second lens L2 has negative optical power, with its object side S3 being concave and its image side S4 being convex.

[0135] The third lens L3 has positive optical power, with its object side S6 being convex and its image side S7 being concave.

[0136] The fourth lens L4 has positive optical power, and its object side S8 is convex, while its image side S9 is convex.

[0137] The fifth lens L5 has negative optical power, and its object side S10 is concave, and its image side S11 is concave.

[0138] The sixth lens L6 has positive optical power, and its object side S11 is convex, and its image side S12 is convex.

[0139] The seventh lens L7 has positive optical power, with its object side S13 being convex and its image side S14 being concave.

[0140] The optical lens may also include an aperture stop STO, which can be positioned between the second lens L2 and the third lens L3 to improve image quality. The fifth lens L5 and the sixth lens L6 form a cemented lens.

[0141] Optionally, the optical lens may also include a filter PB having an object-side surface S15 and an image-side surface S16, and / or a protective glass (not shown) having both an object-side surface and an image-side surface. The filter PB 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 S17. Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto the imaging surface S17.

[0142] Table 7 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens in the optical lens of Example 4, wherein the units of radius of curvature and thickness / distance are millimeters (mm).

[0143]

[0144] Table 7

[0145] In Example 4, the fourth lens is a spherical lens. The object-side and image-side surfaces of any one of the first, second, third, fifth, sixth, and seventh lenses are aspherical. Table 8 shows the higher-order coefficients that can be used for each aspherical mirror in Example 4, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0146] Face number k A4 A6 A8 A10 A12 A14 S1 50.00 -1.34E-03 2.11E-04 -1.37E-05 3.37E-07 0.00E+00 0.00E+00 S2 -0.02 -1.37E-03 6.65E-04 -1.52E-04 2.55E-05 -1.76E-06 0.00E+00 S3 -0.30 4.59E-03 2.59E-04 -4.72E-05 5.88E-06 -7.65E-07 0.00E+00 S4 -0.30 4.07E-03 5.67E-05 5.64E-06 -2.43E-06 9.03E-08 0.00E+00 S6 1.01 2.79E-04 2.12E-05 1.15E-09 -3.85E-07 1.47E-08 0.00E+00 S7 -42.33 -9.06E-04 1.41E-04 -6.21E-07 -4.06E-07 5.40E-10 0.00E+00 S10 -1.08 -4.18E-03 2.82E-04 -6.81E-06 -8.38E-07 2.67E-08 0.00E+00 S11 -21.77 -2.95E-03 2.84E-04 9.77E-06 -1.75E-06 1.59E-08 0.00E+00 S12 -4.71 -1.62E-03 1.48E-04 -4.92E-06 -6.17E-07 3.78E-08 0.00E+00 S13 2.27 2.88E-04 -3.07E-05 -2.42E-06 4.56E-08 0.00E+00 0.00E+00 S14 -50.01 -1.62E-03 6.47E-05 -9.04E-07 -4.53E-08 0.00E+00 0.00E+00

[0147] Table 8

[0148] In summary, Examples 1 to 4 satisfy the relationships shown in Table 9 below.

[0149]

[0150]

[0151] Table 9

[0152] 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.

[0153] 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, The optical lens comprises, sequentially from the object side to the image side along the optical axis: The first lens with negative optical power has a concave image-side surface. A second lens with negative optical power has a concave object side and a convex image side. A third lens with positive optical power has a convex object-side surface and a concave image-side surface; The fourth lens with positive optical power has convex surfaces on both its object side and image side. A fifth lens with negative optical power, wherein both the object-side and image-side surfaces are concave; and The sixth lens has positive optical power, and both its object-side and image-side surfaces are convex. The seventh lens, possessing positive optical power, has a convex object-side surface and a concave image-side surface; among which, The optical lens has seven lenses with optical power. The combined focal length F56 of the fifth lens and the sixth lens satisfies the following condition with respect to the effective focal length F of the optical lens: 7.62≤F56 / F≤16.66; The distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis and the effective focal length F of the optical lens satisfy: 5.24≤TTL / F≤5.

85.

2. The optical lens according to claim 1, wherein, The back focal length BFL of the optical lens and the distance TTL from the object side of the first lens to the imaging surface of the optical lens on the optical axis satisfy the following condition: 0.26≤BFL / TTL≤0.

3.

3. The optical lens according to claim 1, wherein, The effective focal length F1 of the first lens and the effective focal length F of the optical lens satisfy: -1.78≤F1 / F≤-1.

67.

4. The optical lens according to claim 1, wherein, The axial distance ASG1 between the intersection of the object-side surface of the first lens and the optical axis and the vertex of the effective radius of the object-side surface of the first lens satisfies the following condition with respect to the optical half-aperture value D1S1 of the object-side surface of the first lens: -0.02≤ASG1 / D1S1≤0.

10.

5. The optical lens according to claim 1, wherein, The radius of curvature L2R1 of the object side surface of the second lens and the optical half-aperture value D2S1 of the object side surface of the second lens satisfy: -1.44≤L2R1 / D2S1≤-1.

20.

6. The optical lens according to claim 1, wherein, The refractive index ND2 of the second lens and the refractive index ND3 of the third lens satisfy the following condition: 1.59≤(ND2+ND3) / 2≤1.

7.

7. The optical lens according to claim 1, wherein, The effective focal length F2 of the second lens and the effective focal length F of the optical lens satisfy: -46.51≤F2 / F≤-23.

26.

8. The optical lens according to claim 1, wherein, The effective focal length F3 of the third lens and the effective focal length F of the optical lens satisfy the following condition: 4.60≤F3 / F≤5.

81.

9. The optical lens according to claim 1, wherein, The effective focal length F4 of the fourth lens and the effective focal length F of the optical lens satisfy the following condition: 1.91≤F4 / F≤2.

04.

10. The optical lens according to any one of claims 1-9, wherein, The Abbe number VD4 of the fourth lens satisfies: 68.62≤VD4≤90.

19.

11. The optical lens according to any one of claims 1-9, wherein, The effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy the condition: -1.17≤F5 / F6≤-0.

87.

12. The optical lens according to any one of claims 1-9, wherein, The effective focal length F7 of the seventh lens and the effective focal length F of the optical lens satisfy the following condition: 7.49≤F7 / F≤10.

92.

13. The optical lens according to any one of claims 1-9, wherein, The combined focal length F56 of the fifth lens and the sixth lens and the effective focal length F7 of the seventh lens satisfy the condition: 0.70≤F56 / F7≤2.

22.

14. The optical lens according to any one of claims 1-9, wherein, The center thickness D2 of the second lens on the optical axis and the center thickness D3 of the third lens on the optical axis satisfy: 1.22≤D3 / D2≤2.

2.

15. The optical lens according to any one of claims 1-9, wherein, The center thickness D6 of the sixth lens on the optical axis and the center thickness D5 of the fifth lens on the optical axis satisfy the following condition: 1.92≤D6 / D5≤3.

70.

16. The optical lens according to any one of claims 1-9, wherein, The optical lens also includes an aperture stop, and the combined focal length Fb of all lenses on the image side of the aperture stop and the effective focal length F of the optical lens satisfy: 1.59≤Fb / F≤1.

80.

17. The optical lens according to any one of claims 1-9, wherein, The optical lens also includes an aperture stop, and the combined focal length Fa of all lenses on the object side of the aperture stop and the combined focal length Fb of all lenses on the image side of the aperture stop satisfy: -3.3≤Fa / Fb≤-1.0.

Images