Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses in sequence along an optical axis from an object side to an imaging surface, and the seven lenses comprise: a first lens with negative optical power, wherein an image side of the first lens is a concave surface; a second lens with negative optical power, wherein an object side of the second lens is a concave surface and an image side of the second lens is a convex surface; a third lens with positive optical power; a fourth lens with negative optical power; a fifth lens with positive optical power, wherein an object side of the fifth lens is a convex surface; a sixth lens with positive optical power, wherein an image side of the sixth lens is a convex surface; and a seventh lens with negative optical power, wherein an object side of the seventh lens is a concave surface; wherein a curvature radius R3 of the object side of the second lens and a curvature radius R4 of the image side of the second lens satisfy: -1<(R3-R4) / (R3+R4)<0. The optical lens has a large field of view and high resolving power, has good imaging quality, and has clear imaging of an edge field of view through reasonable configuration of surface types of the lenses and reasonable matching of optical powers.

Description

Technical Field

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

[0002] As people's demands for driving experience continue to increase, automotive optical lenses are being used more and more in intelligent driving, and the status of automotive optical lenses in the automotive industry is constantly rising.

[0003] Advanced Driver Assistance Systems (ADAS) play a crucial role in intelligent driving. They use various cameras and sensors to collect environmental information to ensure driver safety. Existing ADAS systems require multiple cameras on both sides of the vehicle to achieve view fusion, and suffer from poor image quality at the edges of the field of view, making it difficult to clearly distinguish obstacles. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of good edge field-of-view imaging effect.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] An optical lens comprises seven lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0007] The first lens with negative optical power has a concave image-side surface.

[0008] A second lens with negative optical power has a concave object side and a convex image side.

[0009] A third lens with positive optical power;

[0010] A fourth lens with negative optical power;

[0011] The fifth lens with positive optical power has a convex object-side surface;

[0012] The sixth lens, which has positive optical power, has a convex image-side surface;

[0013] The seventh lens has negative optical power and its object side is concave.

[0014] Wherein, the object-side radius of curvature R3 of the second lens and the image-side radius of curvature R4 of the second lens satisfy: -1<(R3-R4) / (R3+R4)<0.

[0015] Further optimization, the total optical length (TTL) of the optical lens and the effective focal length (f) satisfy: 15 <TTL / f<30。

[0016] Further preferably, the maximum field of view (FOV) of the optical lens and the aperture value (Fno) of the optical lens satisfy: 70° <FOV / Fno<100°。

[0017] Further preferably, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: IH / f>3.

[0018] Further preferably, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: BFL / f>1.5.

[0019] Further preferably, the true image height IH corresponding to the maximum field of view of the optical lens and the true image height IHm corresponding to the center field of view satisfy: IHm / IH<0.5.

[0020] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: f1 / f < -2.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: f2 / f < -3.

[0022] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: f4 / f < -15.

[0023] Further preferably, the effective focal length f of the optical lens and the radius of curvature R2 of the image side surface of the first lens satisfy: R2 / f>2.

[0024] The optical lens provided by this invention, through the reasonable configuration of the surface shapes of each lens and the reasonable combination of optical power, enables the lens to have a large field of view and high resolution, with good imaging quality and clear imaging at the edge of the field of view. Attached Figure Description

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0026] Figure 1 This is a schematic diagram of the optical lens structure in Embodiment 1 of the present invention.

[0027] Figure 2 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 This is the F-θ distortion curve of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 This is a relative illumination curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 This is an MTF curve of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 6 This is a schematic diagram of the optical lens structure in Embodiment 2 of the present invention.

[0032] Figure 7 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 8 This is the F-θ distortion curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 9 This is a relative illumination curve of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 10 This is the MTF curve of the optical lens in Embodiment 2 of the present invention.

[0036] Figure 11 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 12 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 13 This is the F-θ distortion curve of the optical lens in Embodiment 3 of the present invention.

[0039] Figure 14 This is a relative illumination curve of the optical lens in Embodiment 3 of the present invention.

[0040] Figure 15 This is an MTF curve of the optical lens in Embodiment 3 of the present invention.

[0041] Figure 16 This is a schematic diagram of the optical lens structure in Embodiment 4 of the present invention.

[0042] Figure 17 This is a field curvature curve diagram of the optical lens in Embodiment 4 of the present invention.

[0043] Figure 18 This is the F-θ distortion curve of the optical lens in Embodiment 4 of the present invention.

[0044] Figure 19 This is a relative illumination curve of the optical lens in Embodiment 4 of the present invention.

[0045] Figure 20 This is the MTF curve of the optical lens in Embodiment 4 of the present invention.

[0046] Figure 21This is a schematic diagram of the optical lens structure in Embodiment 5 of the present invention.

[0047] Figure 22 This is a field curvature curve diagram of the optical lens in Embodiment 5 of the present invention.

[0048] Figure 23 This is the F-θ distortion curve of the optical lens in Embodiment 5 of the present invention.

[0049] Figure 24 This is a relative illumination curve of the optical lens in Embodiment 5 of the present invention.

[0050] Figure 25 This is the MTF curve of the optical lens in Embodiment 5 of the present invention.

[0051] Figure 26 This is a schematic diagram of the optical lens in Embodiment 6 of the present invention.

[0052] Figure 27 This is a field curvature curve diagram of the optical lens in Embodiment 6 of the present invention.

[0053] Figure 28 This is the F-θ distortion curve of the optical lens in Embodiment 6 of the present invention.

[0054] Figure 29 This is a relative illumination curve of the optical lens in Embodiment 6 of the present invention.

[0055] Figure 30 This is the MTF curve of the optical lens in Embodiment 6 of the present invention.

[0056] Figure 31 This is a schematic diagram of the optical lens in Embodiment 7 of the present invention.

[0057] Figure 32 This is a field curvature curve diagram of the optical lens in Embodiment 7 of the present invention.

[0058] Figure 33 This is the F-θ distortion curve of the optical lens in Embodiment 7 of the present invention.

[0059] Figure 34 This is a relative illumination curve of the optical lens in Embodiment 7 of the present invention.

[0060] Figure 35 This is the MTF curve of the optical lens in Embodiment 7 of the present invention.

[0061] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0062] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0063] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0064] 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.

[0065] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0066] 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.

[0067] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so specified herein.

[0068] 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.

[0069] The optical lens provided in this embodiment of the invention comprises, in sequence along the optical axis from the object side to the image side: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0070] In some embodiments, the first lens may have negative optical power, with its image-side surface being concave and its object-side surface being either concave or convex. The second lens may have negative optical power, with its object-side surface being concave and its image-side surface being convex. The third lens may have positive optical power, with its object-side surface being either concave or convex and its image-side surface being either concave or convex. The fourth lens may have negative optical power, with its object-side surface being either concave or convex and its image-side surface being either concave or convex. The fifth lens may have positive optical power, with its object-side surface being convex and its image-side surface being either concave or convex. The sixth lens may have positive optical power, with its object-side surface being either concave or convex and its image-side surface being convex. The seventh lens may have negative optical power, with its object-side surface being concave and its image-side surface being either concave or convex.

[0071] In some embodiments, the optical lens may also include an aperture stop, which may be located between the third and fourth lenses. It is understood that the aperture stop is used to limit the amount of light entering the lens, thereby changing the brightness of the image. Furthermore, when the aperture stop is located between the third and fourth lenses, it can rationally allocate the functions of the first to seventh lenses. For example, the first, second, and third lenses can be used to receive light to a greater extent, while the fifth to seventh lenses can be used to correct aberrations, which is beneficial for balancing the overall structure of the optical system. In addition, when the aperture stop is located between the third and fourth lenses, it facilitates the correction of aperture aberrations.

[0072] In some embodiments, the optical lens may further include a filter and a protective glass, which are sequentially disposed between the seventh lens and the imaging plane along the optical axis. The filter is used to filter out interfering light, preventing it from reaching the imaging plane of the optical lens and affecting normal imaging. The protective glass protects the optical lens, preventing damage to the image sensor, and improves the lens's shock and scratch resistance, while having almost no impact on the image quality.

[0073] In some embodiments, the clear aperture radius of the surface located in front of or behind the aperture is the minimum among the clear aperture radii of all lenses. That is, the clear aperture radius of the image side surface of the third lens or the object side surface of the fourth lens is the smallest among the clear aperture radii of all lenses. Meeting the above requirements, during the process where the clear aperture gradually decreases from the object side surface to the aperture surface, the light rays are gradually converged and restricted, which helps to reduce stray light and unwanted reflections, thereby improving the clarity and contrast of the imaging; after the aperture surface, the clear aperture gradually increases, which helps to ensure that more light rays can reach the imaging surface, thereby improving the brightness and signal-to-noise ratio of the image.

[0074] In some embodiments, the radius of curvature R3 of the object side surface of the second lens and the radius of curvature R4 of the image side surface of the second lens satisfy: -1 < (R3 - R4) / (R3 + R4) < 0. Meeting the above range can control the smooth trend of the light rays, reduce the degree of deflection of the light rays passing through the lens, reduce the difficulty of off-axis aberration correction, and improve the imaging quality of the optical lens.

[0075] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f satisfy: 15 < TTL / f < 30. Meeting the above range ensures that there is enough space to adjust the lens structure and optimize the imaging effect.

[0076] In some embodiments, the maximum field of view FOV of the optical lens and the f-number Fno of the optical lens satisfy: 70° < FOV / Fno < 100°. Meeting the above range can match different specifications of aperture sizes, thereby better balancing the relationship between the field of view angle and the aperture size of the optical lens.

[0077] In some embodiments, the effective focal length f of the optical lens and the true image height IH corresponding to the maximum field of view angle of the optical lens satisfy: IH / f > 3. Meeting the above range can reasonably control the relationship between the image height and the focal length, which helps the optical lens to achieve high pixel characteristics.

[0078] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: BFL / f > 1.5. Meeting the above range is beneficial to achieving a balance between obtaining good imaging quality and having an optical back focal length that is easy to assemble, ensuring the imaging quality of the optical lens while avoiding interference between the lens and other components and reducing the assembly process difficulty of the camera module.

[0079] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the true image height IHm corresponding to the central field angle (the value of which is half of the value of the maximum field angle) satisfy: IHm / IH < 0.5. Meeting the above range can highlight the proportion of the imaging range of the edge field in the entire imaging range. Compared with a lens of the same field angle, when matching a chip of the same size, the proportion of the imaging range of the edge field in the entire imaging range is larger, and thus more detailed information can be obtained.

[0080] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: f1 / f < -2. Meeting the above range allows large-angle light rays to enter the optical lens; at the same time, using a relatively large negative focal length helps to control perspective distortion and reduce field curvature, thereby improving the geometric accuracy of the imaging surface.

[0081] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: f2 / f < -3. Meeting the above range enables the second lens to have an appropriate negative optical power, which can share the negative optical power of the first lens and allow large-field-angle light rays to smoothly enter the optical lens to expand the light-receiving range.

[0082] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: f3 / f > 4. Meeting the above range enables the third lens to have a positive optical power, which can effectively correct the aberration generated at the front end of the lens and improve the imaging quality of the lens.

[0083] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: f4 / f < -15. Meeting the above range, by introducing positive distortion, balances the negative distortion value generated in the optical lens and increases the imaging area.

[0084] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 2 < f5 / f < 15. Meeting the above range controls the fifth lens to have an appropriate positive optical power, which helps to reduce the aberration of the optical lens.

[0085] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 2 < f6 / f < 8. Meeting the above range controls the sixth lens to have an appropriate positive optical power, which helps to reduce the aberration of the optical lens.

[0086] In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -5 < f7 / f < -1. Meeting the above range controls the seventh lens to have an appropriate negative optical power, which is beneficial to increasing the area of the imaging surface.

[0087] In some embodiments, the effective focal length f of the optical lens and the radius of curvature R2 of the image side surface of the first lens satisfy: R2 / f > 2. Meeting the above range is beneficial to achieving the characteristics of a wide angle, so as to obtain more scene information and meet the requirements of the large field of view of the optical lens.

[0088] In some embodiments, the distance ∑CT13 from the object side surface of the first lens to the image side surface of the third lens on the optical axis and the total optical length TTL of the optical lens satisfy: 0.5 < ∑CT13 / TTL < 0.8. Meeting the above range and controlling the distance from the object side surface of the first lens to the image side surface of the third lens within the above range is beneficial to increasing the proportion of the front lens group in the entire optical lens, and further reducing the correction difficulty of the aberration of the rear lens group in the peripheral field of view.

[0089] In some embodiments, the distance ∑CT47 from the object side surface of the fourth lens to the image side surface of the seventh lens on the optical axis and the total optical length TTL of the optical lens satisfy: 0.1 < ∑CT47 / TTL < 0.4. Meeting the above range and controlling the distance from the object side surface of the fourth lens to the image side surface of the seventh lens within the above range is beneficial to compressing the total length of the optical lens while ensuring that the rear lens group has appropriate aberration correction ability.

[0090] In some embodiments, the sixth lens and the seventh lens can be glued together to form a glued lens, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing technology difficulty of the optical lens and improving the assembly yield of the optical lens.

[0091] In some embodiments, the optical lens satisfies the conditional formula: 1mm < f < 2mm, 0.5mm < EPD < 1mm, 25mm < TTL < 31mm, 2.0 < Fno < 2.5, 4mm < IH < 8mm, 10° < CRA < 35°, where f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field of view angle of the optical lens, and CRA represents the incident angle of the chief ray at the maximum image height of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least the characteristics of a short focal length and a large image plane.

[0092] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens is made of plastic, production costs can be effectively reduced. Conversely, when the lens is made of glass, the low dispersion characteristic of glass itself can effectively correct geometric chromatic aberration of the optical system. The optical lens provided by the present invention can employ an all-glass lens structure, which can reduce dispersion, effectively correct chromatic aberration of the optical lens, and improve image quality.

[0093] In some embodiments, the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, and seventh lens can be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving lens miniaturization. More specifically, in the optical lens provided by the present invention, the first lens, second lens, third lens, fourth lens, and fifth lens can be aspherical lenses, and the sixth lens and seventh lens can be spherical lenses.

[0094] In various embodiments of the present invention, when an aspherical lens is used, the shapes of each aspherical surface of the optical lens satisfy the following equations:

[0095]

[0096] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, F, and G are the fourth, sixth, eighth, tenth, twelfth, and fourteenth order surface coefficients, respectively.

[0097] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0098] Example 1

[0099] Please see Figure 1 The diagram shown is a schematic diagram of the structure of the optical lens provided in Embodiment 1 of the present invention. The optical lens includes, in sequence along the optical axis from the object side to the imaging plane: a first lens L1, a second lens L2, a third lens L3, an aperture ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0100] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0101] The second lens L2 has negative optical power, its object side S3 is concave, and its image side S4 is convex.

[0102] The third lens L3 has positive optical power, its object side S5 is concave, and its image side S6 is convex.

[0103] The fourth lens L4 has negative optical power, and both its object-side surface S7 and image-side surface S8 are concave.

[0104] The fifth lens L5 has positive optical power, and both its object side S9 and image side S10 are convex surfaces;

[0105] The sixth lens L6 has positive optical power, and both its object-side surface S11 and image-side surface S12 are convex.

[0106] The seventh lens L7 has negative optical power, and both its object-side surface S12 and image-side surface S13 are concave.

[0107] The sixth lens L6 and the seventh lens L7 form a cemented lens group, that is, the cementing surface of the image side of the sixth lens L6 and the object side of the seventh lens L7 is S12.

[0108] The object-side surface S14 and the image-side surface S15 of filter G1 are both planar.

[0109] The object side S16 and image side S17 of the protective glass G2 are both flat.

[0110] The imaging plane S18 is a plane.

[0111] The sixth lens L6 and the seventh lens L7 are glass spherical lenses, while the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are glass aspherical lenses.

[0112] The relevant parameters of each lens in the optical lens of Example 1 are shown in Table 1-1.

[0113] Table 1-1

[0114]

[0115] The surface profile parameters of the aspherical lens in Example 1 are shown in Table 1-2.

[0116] Table 1-2

[0117]

[0118]

[0119] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown.

[0120] Figure 2 The field curvature curve of Example 1 is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within -0.05 mm to 0.02 mm, indicating that the optical lens can effectively correct the field curvature.

[0121] Figure 3 The F-θ distortion curves for Example 1 are shown, representing the F-θ distortion of light of different wavelengths at different image heights on the imaging plane. The horizontal axis represents F-θ distortion (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-θ edge field of view distortion of the optical lens is controlled within a range greater than +20%, indicating that the optical lens possesses significant positive distortion, thereby increasing the proportion of the edge field of view of the optical lens within the entire image plane.

[0122] Figure 4 The relative illumination curves for Example 1 are shown, representing the relative illumination values ​​at different field-of-view angles on the imaging plane. The horizontal axis represents the half-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination.

[0123] Figure 5 The MTF (Modulation Transfer Function) curve of Example 1 is shown, which represents the lens imaging modulation at different spatial frequencies and field of view angles. The horizontal axis represents the field of view angle (unit: °), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of the edge field of view in this example is greater than 0.3 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0124] Example 2

[0125] Please see Figure 6 The figure shows a schematic diagram of the optical lens provided in Embodiment 2 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1. The main difference is that the image side surface S8 of the fourth lens L4 is a convex surface; the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0126] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2-1.

[0127] Table 2-1

[0128]

[0129]

[0130] The surface profile parameters of the aspherical lens in Example 2 are shown in Table 2-2.

[0131] Table 2-2

[0132] Face number K B C D E F G S1 2.71E+00 1.58E-04 -4.01E-07 -8.49E-10 -3.65E-11 3.47E-13 -4.12E-16 S2 4.04E-02 -2.22E-04 -6.05E-06 4.01E-06 -1.85E-08 4.40E-09 1.39E-09 S3 -4.83E+00 1.32E-03 -2.55E-06 -1.69E-06 -1.70E-07 -7.15E-09 -3.62E-10 S4 -9.14E+01 4.05E-04 -7.49E-05 -3.74E-06 -1.90E-07 -3.72E-08 2.40E-09 S5 9.70E+01 -1.60E-03 8.54E-06 2.69E-06 7.59E-07 4.25E-08 -8.26E-09 S6 -6.82E+00 7.80E-07 -2.21E-04 -1.28E-05 6.55E-06 1.67E-06 5.36E-07 S7 9.52E+00 4.66E-03 -7.59E-04 1.56E-04 2.41E-04 -9.92E-05 -1.30E-04 S8 -2.05E+01 9.47E-03 1.36E-03 -1.05E-04 -5.11E-05 -1.84E-05 9.91E-07 S9 2.97E+01 4.30E-04 5.19E-04 -1.70E-04 -1.23E-05 -4.10E-06 1.37E-06 S10 -8.79E-01 -3.02E-03 -2.75E-04 -1.97E-05 -4.34E-06 4.87E-07 -5.58E-08

[0133] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown. From Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.04mm to 0.02mm, indicating that the optical lens can effectively correct field curvature. From Figure 8 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled at around +20%, indicating that the optical lens has significant positive distortion, increasing the proportion of the edge field of view in the entire image plane. From Figure 9 As can be seen, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 10 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.4 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0134] Example 3

[0135] Please see Figure 11 The figure shows a schematic diagram of the optical lens provided in Embodiment 3 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1. The main difference is that the image side surface S13 of the seventh lens L7 is convex. The optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0136] The relevant parameters of each lens in the optical lens of Example 3 are shown in Table 3-1.

[0137] Table 3-1

[0138]

[0139] The surface profile parameters of the aspherical lens in Example 3 are shown in Table 3-2.

[0140] Table 3-2

[0141]

[0142]

[0143] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 12 , Figure 13 , Figure 14 , Figure 15 As shown. From Figure 12 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.05mm to 0.02mm, indicating that the optical lens can effectively correct field curvature. From Figure 13 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled within a range greater than +20%, indicating that the optical lens has significant positive distortion, thereby increasing the proportion of the edge field of view in the entire image plane. From Figure 14 As can be seen, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 15 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.3 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0144] Example 4

[0145] Please see Figure 16 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 4 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1. The main difference is that the object side S5 of the third lens L3 is convex; the image side S10 of the fifth lens L5 is concave; the image side S13 of the seventh lens L7 is convex; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0146] The relevant parameters of each lens in the optical lens of Example 4 are shown in Table 4-1.

[0147] Table 4-1

[0148]

[0149]

[0150] The surface profile parameters of the aspherical lens in Example 4 are shown in Table 4-2.

[0151] Table 4-2

[0152] Face number K B C D E F G S1 4.98E+00 1.81E-04 -3.94E-07 -6.73E-10 -3.08E-11 2.93E-13 -4.95E-16 S2 3.16E-02 -1.26E-04 3.47E-05 2.12E-06 -2.18E-07 2.37E-08 -7.63E-10 S3 -4.10E+00 1.47E-03 -1.69E-07 -1.15E-06 -2.44E-07 4.52E-09 4.91E-10 S4 9.97E+01 2.65E-03 -1.64E-05 6.14E-06 -1.72E-07 -1.70E-07 -1.08E-08 S5 9.95E+01 -3.13E-03 -1.93E-04 -4.39E-06 2.34E-06 8.04E-08 -1.21E-07 S6 -6.96E+00 5.23E-06 -1.76E-04 -1.09E-05 6.13E-06 5.85E-06 -1.59E-06 S7 -1.00E+02 1.02E-02 -8.38E-04 -4.65E-05 3.04E-04 -5.14E-05 -2.03E-05 S8 -1.00E+02 6.36E-03 1.41E-03 3.69E-05 -1.84E-05 -1.28E-05 -9.08E-07 S9 2.82E+01 2.55E-03 5.88E-04 -2.09E-04 -3.65E-05 -1.72E-05 -9.43E-06 S10 1.00E+02 1.60E-03 -1.10E-04 -8.38E-06 -1.48E-05 -7.81E-07 2.87E-07

[0153] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 17 , Figure 18 , Figure 19 , Figure 20 As shown. From Figure 17 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.06mm to 0.02mm, indicating that the optical lens can effectively correct field curvature. From Figure 18 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled within a range greater than +20%, indicating that the optical lens has significant positive distortion, thereby increasing the proportion of the edge field of view in the entire image plane. From Figure 19 As can be seen, the relative illumination value of the optical lens is still greater than 98% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 20 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.35 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0154] Example 5

[0155] Please see Figure 21 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 8 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1. The main difference is that the object side S5 of the third lens L3 is a convex surface; the image side S6 of the third lens L3 is a concave surface; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0156] The relevant parameters of each lens in the optical lens of Example 5 are shown in Table 5-1.

[0157] Table 5-1

[0158]

[0159] The surface profile parameters of the aspherical lens in Example 5 are shown in Table 5-2.

[0160] Table 5-2

[0161]

[0162]

[0163] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 22 , Figure 23 , Figure 24 , Figure 25 As shown. From Figure 22 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.04mm to 0.02mm, indicating that the optical lens can effectively correct field curvature. From Figure 23 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled within a range greater than +20%, indicating that the optical lens has significant positive distortion, thereby increasing the proportion of the edge field of view in the entire image plane. From Figure 24 As can be seen, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 25 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.2 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0164] Example 6

[0165] Please see Figure 26 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 6 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the object side surface S1 of the first lens L1 is concave; the object side surface S5 of the third lens L3 is convex; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0166] The relevant parameters of each lens in the optical lens of Example 6 are shown in Table 6-1.

[0167] Table 6-1

[0168]

[0169]

[0170] The surface profile parameters of the aspherical lens in Example 6 are shown in Table 6-2.

[0171] Table 6-2

[0172] Face number K B C D E F G S1 1.00E+02 2.26E-04 -4.15E-07 -1.03E-09 -3.77E-11 3.28E-13 -5.24E-16 S2 6.03E-02 -1.18E-03 -1.68E-05 6.09E-06 1.81E-07 1.02E-08 2.06E-09 S3 -3.49E+00 1.10E-03 2.14E-05 -2.28E-06 -2.71E-07 -1.98E-08 -1.04E-09 S4 -9.75E+01 4.77E-04 -9.28E-05 -3.75E-06 -2.91E-07 -3.10E-08 2.92E-09 S5 -5.52E+01 -1.71E-03 1.59E-05 1.47E-06 5.87E-07 4.78E-08 -3.23E-09 S6 -5.83E+00 -7.45E-05 -1.81E-04 1.25E-05 1.49E-05 -2.06E-06 5.82E-08 S7 8.85E+00 4.54E-03 -6.99E-04 1.11E-04 2.63E-04 -7.17E-05 -7.82E-05 S8 -9.69E+01 9.45E-03 1.33E-03 -6.93E-05 -3.12E-05 -8.45E-06 1.62E-06 S9 3.03E+01 5.56E-04 4.91E-04 -1.91E-04 -1.84E-05 -3.46E-06 2.01E-06 S10 -9.43E-01 -3.10E-03 -3.10E-04 -2.34E-05 -5.03E-06 3.15E-07 -9.36E-08

[0173] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 27 , Figure 28 , Figure 29 , Figure 30 As shown. From Figure 27 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.02mm to 0.02mm, indicating that the optical lens can effectively correct field curvature. From Figure 28 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled within a range greater than +20%, indicating that the optical lens has significant positive distortion, thereby increasing the proportion of the edge field of view in the entire image plane. From Figure 29 As can be seen, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 30 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.2 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0174] Example 7

[0175] Please see Figure 31 The diagram shows a schematic of the optical lens provided in Embodiment 7 of the present invention. The optical lens in this embodiment is generally the same as that in Embodiment 1, except that: the sixth lens L6 and the seventh lens L7 are not cemented lenses; the object-side surface S5 of the third lens L3 is convex; the object-side surface S7 of the fourth lens L4 is convex; the object-side surface S11 of the sixth lens L6 is concave; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0176] The relevant parameters of each lens in the optical lens of Example 7 are shown in Table 7-1.

[0177] Table 7-1

[0178]

[0179] The surface profile parameters of the aspherical lens in Example 7 are shown in Table 7-2.

[0180] Table 7-2

[0181]

[0182]

[0183] In this embodiment, the field curvature curve, F-θ distortion curve, relative illumination curve, and MTF curve of the optical lens are respectively as follows: Figure 32 , Figure 33 , Figure 34 , Figure 35 As shown. From Figure 32As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.15mm to -0.05mm, indicating that the optical lens can effectively correct field curvature. From Figure 33 As can be seen, the F-θ edge field-of-view distortion of the optical lens is controlled at around +18%, indicating that the optical lens has significant positive distortion, increasing the proportion of the edge field of view in the entire image plane. From Figure 34 As can be seen, the relative illumination value of the optical lens is still greater than 70% at the maximum half-field angle, indicating that the optical lens has good relative illumination. From Figure 35 As can be seen, the MTF value of the edge field of view in this embodiment is greater than 0.2 at a spatial frequency of 160 lp / mm, indicating that the optical lens maintains good imaging quality and good detail resolution at the edge field of view.

[0184] Please refer to Table 8 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, principal ray incident angle CRA at the maximum image height, and maximum field of view FOV, as well as the values ​​corresponding to each conditional expression in each embodiment.

[0185] Table 8

[0186]

[0187]

[0188] In summary, the optical lens provided by the present invention, through the reasonable configuration of the surface shapes of each lens and the reasonable matching of optical power, enables the lens to have a large field of view and high resolution, has good imaging quality, improves the imaging quality at the edge of the field of view, and makes the edge field of view clear.

[0189] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0190] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens comprising seven lenses, characterized in that, It successively includes from the object side to the imaging surface along the optical axis: A first lens with negative optical power, whose image side is concave; A second lens with negative optical power, whose object side is concave and image side is convex; A third lens with positive optical power; A fourth lens with negative optical power; A fifth lens with positive optical power, whose object side is convex; A sixth lens with positive optical power, whose image side is convex; A seventh lens with negative optical power, whose object side is concave; Wherein, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: -1 < (R3 - R4) / (R3 + R4) < 0; The overall optical length TTL of the optical lens and the effective focal length f satisfy: 15 < TTL / f < 30; The maximum field angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 70° < FOV / Fno < 100°; The true image height IH corresponding to the maximum field angle of the optical lens and the true image height IHm corresponding to half of the value of the maximum field angle satisfy: 0.42 ≤ IHm / IH < 0.5; 2. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 2 < f5 / f < 15, and the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 2 < f6 / f < 8; 3. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy: -5 < f7 / f < -1; 4. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 3.51 ≥ IH / f > 3; 5. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 2.07 ≥ BFL / f > 1.5; 6. The optical lens according to claim 1, characterized in that, The distance ∑CT13 from the object side of the first lens to the image side of the third lens on the optical axis and the overall optical length TTL of the optical lens satisfy: 0.5 < ∑CT13 / TTL < 0.8; 7. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -4.64 ≤ f1 / f < -2; 8. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -10.10 ≤ f2 / f < -3; 9. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -137.75 ≤ f4 / f < -15; 10. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the radius of curvature R2 of the image side of the first lens satisfy: 3.06 ≥ R2 / f > 2;

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