Optical lens

Abstract

The application provides an optical lens, which comprises, along an optical axis from an object side to an imaging surface, a first lens with negative focal length, the object side of which is a convex surface and the image side of which is a concave surface; a second lens with negative focal length, the object side of which is a convex surface and the image side of which is a concave surface; a third lens with positive focal length, the object side of which is a convex surface and the image side of which is a plane; a fourth lens with positive focal length, the object side of which is a convex surface and the image side of which is a convex surface; a fifth lens with negative focal length, the image side of which is a concave surface; a sixth lens with positive focal length, the image side of which is a convex surface; a seventh lens with negative focal length, the object side of which is a convex surface near the optical axis and the image side of which is a concave surface near the optical axis; and an eighth lens with positive focal length, the object side of which is a convex surface near the optical axis and the image side of which is a concave surface near the optical axis. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration and improve the imaging quality of the optical lens.

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 drones continue to upgrade and evolve, consumers have increasingly higher demands for drone functionality, with ultra-high resolution, large aperture, and wide-angle shooting becoming the main development trends. To pursue high-quality imaging, most mainstream drones currently use all-glass lenses, with the number of lenses increasing from 5-6 to 7-8 to correct the optical path. However, due to the limitations of glass lenses, their weight and size are difficult to reduce, and all-glass lenses have reached a bottleneck. Because plastic lenses are lighter and thinner, and have better plasticity, lenses using plastic lenses can be effectively made thinner and lighter. Combining the advantages of plastic lenses, wide field-of-view shooting can be achieved while ensuring the amount of light entering the optical lens and image clarity. This is expected to be applied in high-end drones and represents the future development trend of drone lenses. However, how to better achieve wide field-of-view, large-area imaging, and high-resolution performance remains a problem that urgently needs to be solved. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0004] The technical solution adopted in this invention is as follows:

[0005] An optical lens comprising eight lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0006] The first lens with negative optical power has a convex object side and a concave image side.

[0007] A second lens with negative optical power has a convex object side and a concave image side.

[0008] A third lens with positive optical power has a convex object-side surface and a flat image-side surface;

[0009] The fourth lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0010] The fifth lens has negative optical power and its image-side surface is concave.

[0011] The sixth lens has positive optical power and its image-side surface is convex.

[0012] The seventh lens with negative optical power has an object-side surface that is convex near the optical axis and an image-side surface that is concave near the optical axis.

[0013] The eighth lens with positive optical power has an object-side surface that is convex near the optical axis and an image-side surface that is concave near the optical axis.

[0014] Among them, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.8 < IH / f < 4.4.

[0015] Further preferably, the overall optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 5.4 mm < TTL / Fno < 6.3 mm.

[0016] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 10.6 < IH / EPD < 12.1.

[0017] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -4.7 < f1 / f < -3.5; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -2.4 < f2 / f < -1.8.

[0018] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 1.75.

[0019] Further preferably, the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis and the overall optical length TTL of the optical lens satisfy: 1.8 < TTL / ∑CT < 2.2.

[0020] Further preferably, the focal length f1 of the first lens, the object-side curvature radius R1 of the first lens, and the image-side curvature radius R2 of the first lens satisfy: -0.95 < f1 / (R1 + R2) < -0.75.

[0021] Further preferably, the object-side end clear aperture sagittal height SAGX11 of the first lens and the central thickness CT1 of the first lens satisfy: 1.5 < SAGX11 / CT1 < 2.8.

[0022] Further preferably, the image-side curvature radius R12 of the sixth lens and the image-side curvature radius R14 of the seventh lens satisfy: -1.7 < R12 / R14 < -1.4.

[0023] Further preferably, the object-side end clear aperture CSD81 of the eighth lens and the object-side end clear aperture sagittal height SAGX81 of the eighth lens satisfy: -20 < CSD81 / SAGX81 < -6.

[0024] Compared with existing technologies, the optical lens provided by this invention uses eight lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as a large field of view, miniaturization, large target surface, and high pixel count. 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 a distortion curve of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 This is a longitudinal chromatic aberration curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 This is a chromatic aberration 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 a distortion curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 9 This is a longitudinal chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 10 This is a chromatic aberration 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 a distortion curve of the optical lens in Embodiment 3 of the present invention.

[0039] Figure 14 This is a longitudinal chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0040] Figure 15 This is a chromatic aberration 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 a distortion curve diagram of the optical lens in Embodiment 4 of the present invention.

[0044] Figure 19 This is a longitudinal chromatic aberration curve of the optical lens in Embodiment 4 of the present invention.

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

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

[0049] Figure 24 This is a longitudinal chromatic aberration curve of the optical lens in Embodiment 5 of the present invention.

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

[0051] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] The optical lens provided by the embodiment of the present invention comprises eight lenses, which are, in sequence from the object side to the imaging surface along the optical axis, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens.

[0060] In some embodiments, the first lens may have a negative optical power, its object side is convex, and its image side is concave. The second lens may have a negative optical power, its object side is convex, and its image side is concave. The third lens may have a positive optical power, its object side is convex, and its image side is flat. The fourth lens may have a positive optical power, its object side is convex, and its image side is convex. The fifth lens may have a negative optical power, its object side may be concave or convex, and its image side is concave. The sixth lens may have a positive optical power, its object side may be concave or convex, and its image side is convex. The seventh lens may have a negative optical power, its object side is convex near the optical axis, and its image side is concave near the optical axis. The eighth lens may have a positive optical power, its object side is convex near the optical axis, and its image side is concave near the optical axis.

[0061] In some embodiments, the optical lens may further include an aperture, and the aperture may be located between the third lens and the fourth lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the image. When the aperture is located between the third lens and the fourth lens, it is convenient for the correction of aperture aberration.

[0062] In some embodiments, the optical lens may further include a filter, and the filter may be disposed between the eighth lens and the imaging surface. The filter is used to filter out interfering light to prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0063] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.8 < IH / f < 4.4. Satisfying the above conditional formula can achieve the characteristics of a large image surface and a large field angle of the optical lens, enabling the optical lens to match a larger-sized chip, and achieving high-pixel imaging while meeting the requirements of a large target surface.

[0064] In some embodiments, the overall optical length TTL of the optical lens and the F-number Fno of the optical lens satisfy: 5.4 mm < TTL / Fno < 6.3 mm. Satisfying the above conditional formula, by controlling the relationship between the overall length and the F-number of the optical lens, it is ensured that the optical lens can meet the requirements of a large aperture and miniaturization design, enabling the optical lens to obtain sufficient light transmission in a dim environment and meeting the needs of high-quality and high-definition shooting.

[0065] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 10.6 < IH / EPD < 12.1. Meeting the above conditional formula can enable an optical lens with a large image plane to have a relatively large entrance pupil diameter and a relatively high light passing amount, thereby improving the imaging effect when the optical lens works in a dark environment, and reducing the aberration of the marginal field of view.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -4.7 < f1 / f < -3.5; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -2.4 < f2 / f < -1.8. Meeting the above conditional formula, by setting both the first lens and the second lens of the optical lens as lenses with negative optical power, the incident angle of light can be converged, the field angle range of the optical lens can be expanded, and at the same time, the back focal length of the optical lens can be increased to avoid interference between the lens and the photosensitive chip; at the same time, the second lens having negative optical power is also beneficial for aberration correction and can further improve the imaging quality of the optical lens.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 1.75. Meeting the above conditional formula, by setting a third lens with positive optical power and defining the ratio of the focal length of the third lens to the effective focal length of the optical lens, it is beneficial to adjust the light path of the light from the first lens and the second lens, so that the optical lens has certain characteristics of a large field angle, low sensitivity and miniaturization.

[0068] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis respectively and the overall optical length TTL of the optical lens satisfy: 1.8 < TTL / ∑CT < 2.2. Meeting the above conditional formula, reasonably configuring the overall optical length of the optical lens and the sum of the thicknesses of each lens helps to achieve high pixel characteristics and improve the imaging quality of the optical lens; at the same time, it can effectively shorten the overall optical length of the optical lens and meet the design requirements of miniaturization and light weight.

[0069] In some embodiments, the focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: -0.95 < f1 / (R1 + R2) < -0.75. Meeting the above conditional formula can constrain the surface shapes of the object side and the image side of the first lens, which is beneficial to reducing the bending degree of light at the image side surface of the first lens and reducing the astigmatism amount of the optical lens, so as to balance the astigmatism problem brought by the large field angle of the optical lens, and ensure that the astigmatism is not too large while the optical lens has a large field of view, thereby ensuring that the optical lens has excellent imaging quality.

[0070] In some embodiments, the sagittal height SAGX11 of the clear aperture semi-diameter at the object side end of the first lens and the central thickness CT1 of the first lens satisfy: 1.5 < SAGX11 / CT1 < 2.8. By satisfying the above conditional formula and controlling the ratio of the sagittal height of the object side surface of the first lens to the central thickness of the first lens on the optical axis, the surface shape of the object side surface can be made to tend to be curved; at the same time, a larger sagittal height is beneficial for the first lens to collect light in a large field of view, achieving high angular resolution at the center of the optical lens, and thus improving the imaging quality of the central region.

[0071] In some embodiments, the curvature radius R12 of the image side surface of the sixth lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: -1.7 < R12 / R14 < -1.4. By satisfying the above conditions, by reasonably controlling the ratio of the curvature radius of the image side surface of the sixth lens to the curvature radius of the image side surface of the seventh lens, the surface shapes of the sixth lens and the seventh lens can be effectively controlled within a reasonable range, facilitating processing and assembly. At the same time, the sixth lens and the seventh lens can converge the aberrations of the marginal field of view, balance the overall aberration of the optical lens, and improve the imaging quality of the lens.

[0072] In some embodiments, the clear aperture semi-diameter CSD81 at the object side end of the eighth lens and the sagittal height SAGX81 of the clear aperture semi-diameter at the object side end of the eighth lens satisfy: -20 < CSD81 / SAGX81 < -6. By satisfying the above conditions, controlling the surface shape of the object side end of the eighth lens helps the light to transition smoothly, and at the same time can improve the ghost image of the optical lens, reduce the sensitivity of the optical lens, and enhance the imaging quality.

[0073] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: -2.8 < f5 / f < -2.2. By satisfying the above conditions, the fifth lens can have an appropriate negative optical power, which is beneficial for balancing various aberrations generated by the lens, enhancing the imaging quality of the optical lens while increasing its imaging area and improving the imaging quality.

[0074] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -1.6 < f7 / f < -1.3. By satisfying the above conditions, reasonably distributing the optical power of the seventh lens can make the light rays smoothly enter the image plane after being lifted upward, which is beneficial for meeting the requirements of a large target surface, and at the same time is beneficial for correcting the residual aberrations of the optical lens and further improving the imaging quality.

[0075] In some embodiments, the spacing CT12 between the first lens and the second lens on the optical axis and the total optical length TTL of the optical lens satisfy: 0.1 < CT12 / TTL < 0.3. By satisfying the above conditional formula and reasonably restricting the air gap between the first lens and the second lens, the light deflection can tend to be slow, which is beneficial for reducing the sensitivity of the optical lens.

[0076] In some embodiments, the clear aperture semi-diameter CSD82 of the image side end of the eighth lens and the sagittal height SAGX82 of the clear aperture semi-diameter of the image side end of the eighth lens satisfy: -9.6 < CSD82 / SAGX82 < -4.6. Meeting the above conditions can converge the marginal field light rays, which helps to optimize the imaging performance under low light conditions and provide better image brightness and contrast.

[0077] In some embodiments, the curvature radius R13 of the object side surface of the seventh lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: 1.1 < (R13 + R14) / (R13 - R14) < 2. Meeting the above conditions can effectively control the surface shape of the seventh lens, effectively improve the aberration of the marginal field, and improve the imaging quality.

[0078] In some embodiments, the central thickness CT6 of the sixth lens and the edge thickness ET6 of the sixth lens satisfy: 1.4 < CT6 / ET6 < 2.3. Meeting the above conditions, the sixth lens has a reasonable surface shape change, can provide sufficient positive refracting power for the optical lens to balance the aberration generated by the first lens to the fifth lens, and thus balance the aberration of the optical lens. At the same time, the sixth lens also has a suitable thickness ratio, and the surface shape change is not too large or too small, thereby reducing the forming and assembling difficulty of the lens.

[0079] In some embodiments, the optical lens satisfies the conditional formula: 130° ≤ FOV ≤ 140°, 15 mm < TTL < 17 mm, 2.7 ≤ Fno < 2.85, 11 mm < IH < 13 mm; where FOV represents the maximum field of view angle of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, and IH represents the true image height corresponding to the maximum field of view angle of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention at least has the characteristics of miniaturization, large field of view angle, large target surface, etc.

[0080] In some embodiments, the eight lenses in the optical lens can all adopt plastic lenses or adopt a glass-plastic hybrid material matching structure. Preferably, the optical lens of the present invention adopts an eight-piece glass-plastic hybrid matching lens structure, which can enable the optical lens to better match the large target surface chip to achieve high-definition imaging, and at the same time can also achieve a reasonable balance of miniaturization, large image surface and large field of view angle of the optical lens. Specifically, the first lens and the third lens can adopt glass lenses, and the second lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are all plastic lenses; adopting the glass-plastic hybrid structure can improve the thermal stability of the optical lens, reduce aberration and distortion, and make the imaging of the optical lens clearer and sharper.

[0081] In some embodiments, the first, second, third, fourth, fifth, sixth, seventh, and eighth lenses can be spherical or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce the aberrations of the optical system, thereby reducing the number of lenses and their size, and better achieving lens miniaturization. More specifically, the first and third lenses of this invention are spherical lenses, while the second, fourth, fifth, sixth, seventh, and eighth lenses can all be aspherical lenses, which can effectively reduce the aberrations of the optical lens, thereby reducing the number of lenses and their size, and better achieving lens miniaturization.

[0082] 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:

[0083]

[0084] 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, G, and H are the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order surface coefficients, respectively.

[0085] 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.

[0086] Example 1

[0087] Please see Figure 1 The diagram shown is a schematic diagram of the structure of the optical lens 100 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, an eighth lens L8, and a filter G1.

[0088] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0089] The second lens L2 has negative optical power, its object side S3 is convex, and its image side S4 is concave.

[0090] The third lens L3 has positive optical power, its object side S5 is convex, and its image side S6 is flat.

[0091] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is convex.

[0092] The fifth lens L5 has negative optical power, its object side S9 is convex near the optical axis, and its image side S10 is concave.

[0093] The sixth lens L6 has positive optical power, its object side S11 is convex near the optical axis, and its image side S12 is convex.

[0094] The seventh lens L7 has negative optical power. Its object-side surface S13 is convex near the optical axis, and its image-side surface S14 is concave near the optical axis.

[0095] The eighth lens L8 has positive optical power, its object side S15 is convex near the optical axis, and its image side S16 is concave near the optical axis.

[0096] The object-side surface S17 and the image-side surface S18 of filter G1 are both planar.

[0097] The imaging plane S19 is a plane.

[0098] The first lens L1 and the third lens L3 are glass spherical lenses, while the second lens L2, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all plastic aspherical lenses.

[0099] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0100] Table 1-1

[0101]

[0102] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0103] Table 1-2

[0104]

[0105]

[0106] In this embodiment, the field curvature curve, distortion curve, longitudinal chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown.

[0107] Figure 2 The field curvature curve of the optical lens 100 in this embodiment is shown, which represents the field curvature of light in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.1 mm, indicating that the optical lens 100 can correct the field curvature well.

[0108] Figure 3 The diagram shows the distortion curve of the optical lens 100 in this embodiment, which represents the distortion at different field-of-view angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the field-of-view angle (unit: °). As can be seen from the figure, the distortion value is controlled within -30% to 0, indicating that the optical lens 100 can correct distortion well.

[0109] Figure 4 The diagram shows the longitudinal chromatic aberration curve of the optical lens 100 in this embodiment. It represents the chromatic aberration of each wavelength on the optical axis at the imaging plane. The horizontal axis represents the longitudinal chromatic aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the figure, the offset of the longitudinal chromatic aberration is controlled within ±0.03 mm, indicating that the optical lens 100 can effectively correct the longitudinal chromatic aberration.

[0110] Figure 5 The diagram shows the transverse chromatic aberration curve of the optical lens 100 in this embodiment. It represents the chromatic aberration of each wavelength relative to the center wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the figure, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±5 μm, indicating that the optical lens 100 can effectively correct transverse chromatic aberration.

[0111] Example 2

[0112] Please see Figure 6 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0113] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0114] Table 2-1

[0115]

[0116]

[0117] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0118] Table 2-2

[0119]

[0120] In this embodiment, the field curvature curve, distortion curve, longitudinal chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown.

[0121] from Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 200 can effectively correct the field curvature.

[0122] from Figure 8 As can be seen, the distortion value is controlled within -30% to 0, indicating that the optical lens 200 can correct distortion well.

[0123] from Figure 9 As can be seen, the offset of the longitudinal chromatic difference is controlled within ±0.02mm, indicating that the optical lens 200 can effectively correct the longitudinal chromatic difference.

[0124] from Figure 10 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±5.5μm, indicating that the optical lens 200 can effectively correct transverse chromatic aberration.

[0125] Example 3

[0126] Please see Figure 11 The figure shown is a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0127] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0128] Table 3-1

[0129]

[0130] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0131] Table 3-2

[0132]

[0133] In this embodiment, the field curvature curve, distortion curve, longitudinal chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 300 are respectively as follows: Figure 12 , Figure 13 , Figure 14 , Figure 15 As shown.

[0134] from Figure 12 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 300 can effectively correct the field curvature.

[0135] from Figure 13 As can be seen, the distortion value is controlled within -20% to 0, indicating that the optical lens 300 can correct distortion well.

[0136] from Figure 14 As can be seen, the offset of the longitudinal chromatic difference is controlled within ±0.03mm, indicating that the optical lens 300 can effectively correct the longitudinal chromatic difference.

[0137] from Figure 15 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±5μm, indicating that the optical lens 300 can effectively correct transverse chromatic aberration.

[0138] Example 4

[0139] Please see Figure 16 The figure shows a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S11 of the sixth lens L6 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0140] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0141] Table 4-1

[0142]

[0143]

[0144] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0145] Table 4-2

[0146]

[0147] In this embodiment, the field curvature curve, distortion curve, longitudinal chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 400 are respectively as follows: Figure 17 , Figure 18, Figure 19 , Figure 20 As shown.

[0148] from Figure 17 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 400 can effectively correct the field curvature.

[0149] from Figure 18 As can be seen, the distortion value is controlled within -30% to 0, indicating that the optical lens 400 can correct distortion well.

[0150] from Figure 19 As can be seen, the offset of the longitudinal chromatic aberration is controlled within ±0.02mm, indicating that the optical lens 400 can effectively correct the longitudinal chromatic aberration.

[0151] from Figure 20 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±4.5μm, indicating that the optical lens 400 can effectively correct transverse chromatic aberration.

[0152] Example 5

[0153] Please see Figure 21 The figure shows a schematic diagram of the structure of the optical lens 500 provided in Embodiment 5 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object side surface S9 of the fifth lens L5 is concave; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0154] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0155] Table 5-1

[0156]

[0157]

[0158] The surface profile parameters of the aspherical lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0159] Table 5-2

[0160]

[0161] In this embodiment, the field curvature curve, distortion curve, longitudinal chromatic aberration curve, and transverse chromatic aberration curve of the optical lens 500 are respectively as follows: Figure 22 , Figure 23 , Figure 24 , Figure 25 As shown.

[0162] from Figure 22As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.1mm, indicating that the optical lens 500 can effectively correct field curvature.

[0163] from Figure 23 As can be seen, the distortion value is controlled within ±10%, indicating that the optical lens 500 can correct distortion well.

[0164] from Figure 24 As can be seen, the offset of the longitudinal chromatic aberration is controlled within ±0.04mm, indicating that the optical lens 500 can effectively correct the longitudinal chromatic aberration.

[0165] from Figure 25 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within ±5μm, indicating that the optical lens 500 can effectively correct transverse chromatic aberration.

[0166] Please refer to Table 6 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, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0167] Table 6

[0168] Parameters and conditional expressions Example 1 Example 2 Example 3 Example 4 Example 5 f(mm) 3.22 3.18 2.85 3.240 2.820 FOV (°) 140.00 140.00 140.00 140.00 130.00 EPD (mm) 1.15 1.14 1.02 1.157 1.019 TTL(mm) 15.63 15.54 16.52 15.360 16.750 Fno 2.80 2.80 2.80 2.820 2.700 IH(mm) 12.26 12.26 12.26 12.70 11.40 TTL / Fno(mm) 5.58 5.55 5.90 5.45 6.20 IH / EPD 10.66 10.78 12.03 10.98 11.19 IH / f 3.81 3.85 4.30 3.92 4.04 f1 / f -3.69 -3.60 -4.44 -3.85 -4.60 f2 / f -1.91 -1.96 -2.32 -1.89 -2.35 f3 / f 1.53 1.53 1.68 1.62 1.71 f5 / f -2.26 -2.43 -2.79 -2.44 -2.41 f7 / f -1.52 -1.33 -1.32 -1.42 -1.43 TTL / ∑CT 1.94 1.90 2.06 1.89 2.12 CT12 / TTL 0.19 0.19 0.24 0.18 0.25 f1 / (R1+R2) -0.85 -0.84 -0.76 -0.91 -0.81 SAGX11 / CT1 2.10 2.10 2.71 1.57 2.39 R12 / R14 -1.61 -1.66 -1.58 -1.43 -1.50 CSD81 / SAGX81 -6.18 -12.36 -11.18 -10.88 -19.81 CSD82 / SAGX82 -4.67 -6.69 -6.39 -7.44 -9.55 (R13+R14) / (R13-R14) 1.83 1.69 1.14 1.91 1.19 CT6 / ET6 2.16 1.88 2.29 1.42 2.02

[0169] In summary, the optical lens provided by the present invention has at least the following advantages:

[0170] (1) By setting specific surface shapes and allocating reasonable optical power, the overall length of the optical lens can be effectively shortened, which is conducive to the miniaturization of the optical lens; at the same time, it has a large field of view, which improves the lens resolution and the range of the receiving field of view.

[0171] (2) The large target surface of the lens can be matched with the imaging chip with a larger target surface to achieve high-definition imaging. Moreover, the increase in the target surface can make the pixel distribution more sparse (i.e., the pixel size is larger), which can effectively reduce noise even in darker environments. The dynamic range is also wider, and more details can be retained in the dark areas, thus presenting a clearer shooting effect. At the same time, it can also reasonably correct the overall aberration of the optical lens, so that the optical lens has high pixels and improves the imaging quality of the optical lens.

[0172] 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.

[0173] 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 eight lenses, characterized in that, It successively includes from the object side to the imaging plane along the optical axis: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a negative optical power, whose object side is convex and whose image side is concave; A third lens with a positive optical power, whose object side is convex and whose image side is flat; A fourth lens with a positive optical power, whose object side is convex and whose image side is convex; A fifth lens with a negative optical power, whose image side is concave; A sixth lens with a positive optical power, whose image side is convex; A seventh lens with a negative optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; An eighth lens with a positive optical power, whose object side is convex near the optical axis and whose image side is concave near the optical axis; Wherein, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.8 < IH / f < 4.4; The overall optical length TTL of the optical lens and the f-number Fno of the optical lens satisfy: 5.4mm < TTL / Fno < 6.3mm.

2. The optical lens according to claim 1, characterized in that, The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: -1.6 < f7 / f < -1.

3.

3. The optical lens according to claim 1, characterized in that, The true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 10.6 < IH / EPD < 12.

1.

4. 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: -4.7 < f1 / f < -3.5; the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -2.4 < f2 / f < -1.

8.

5. The optical lens according to claim 1, characterized in that, The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 1.

75.

6. The optical lens according to claim 1, characterized in that, The sum ∑CT of the central thicknesses of the first lens to the eighth lens along the optical axis respectively and the overall optical length TTL of the optical lens satisfy: 1.8 < TTL / ∑CT < 2.

2.

7. The optical lens according to claim 1, characterized in that, The focal length f1 of the first lens, the curvature radius R1 of the object side of the first lens and the curvature radius R2 of the image side of the first lens satisfy: -0.95 < f1 / (R1 + R2) < -0.

75.

8. The optical lens according to claim 1, characterized in that, The sagittal height SAGX11 of the clear aperture semi-diameter at the object side end of the first lens and the central thickness CT1 of the first lens satisfy: 1.5 < SAGX11 / CT1 < 2.

8.

9. The optical lens according to claim 1, characterized in that, The curvature radius R12 of the image side of the sixth lens and the curvature radius R14 of the image side of the seventh lens satisfy: -1.7 < R12 / R14 < -1.

4.

10. The optical lens according to claim 1, characterized in that, The clear aperture semi-diameter CSD81 at the object side end of the eighth lens and the sagittal height SAGX81 of the clear aperture semi-diameter at the object side end of the eighth lens satisfy: -20 < CSD81 / SAGX81 < -6.

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