Optical lens

Abstract

The application provides an optical lens, which comprises eight lenses in sequence along an optical axis from an object side to an imaging surface, and the eight lenses comprise: a first lens with negative optical power, wherein the object side surface of the first lens is a convex surface and the image side surface of the first lens is a concave surface; a second lens with negative optical power, wherein the object side surface of the second lens is a concave surface; a third lens with positive optical power, wherein the object side surface of the third lens is a convex surface and the image side surface of the third lens is a convex surface; a fourth lens with positive optical power, wherein the object side surface of the fourth lens is a convex surface and the image side surface of the fourth lens is a convex surface; a fifth lens with positive optical power, wherein the image side surface of the fifth lens is a convex surface; a sixth lens with negative optical power, wherein the object side surface of the sixth lens is a concave surface; a seventh lens with positive optical power, wherein the object side surface of the seventh lens is a convex surface and the image side surface of the seventh lens is a convex surface; and an eighth lens with optical power, wherein the image side surface of the eighth lens is a concave surface at a near optical axis. The optical lens provided by the application can improve the imaging quality of the optical lens and has the advantage of excellent imaging quality through specific surface shape matching and reasonable optical power distribution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] In the field of unmanned aerial vehicle photogrammetry, the demand for ultra-wide-angle lenses is extremely urgent. At present, the mainstream unmanned aerial vehicle ultra-wide-angle lenses realize the shooting effect by enlarging the aperture and increasing the size of the lens group to meet various aerial photography tasks. However, such lenses have obvious disadvantages. In complex light and high contrast scenes, overexposure and underexposure are easy to occur, resulting in a large amount of detail loss. Complex means are used to correct distortion, which causes the weight, volume and power consumption of the lens to increase dramatically, seriously restricting the performance of the unmanned aerial vehicle. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens, which has the advantages of excellent imaging quality.

[0004] The present application provides an optical lens, which has eight lenses, and comprises, in order from the object side to the imaging surface along the optical axis: a first lens with negative focal power, whose object side surface is a convex surface, and whose image side surface is a concave surface;

[0005] a second lens with negative focal power, whose object side surface is a concave surface;

[0006] a third lens with positive focal power, whose object side surface is a convex surface, and whose image side surface is a convex surface;

[0007] a fourth lens with positive focal power, whose object side surface is a convex surface, and whose image side surface is a convex surface;

[0008] a fifth lens with positive focal power, whose image side surface is a convex surface;

[0009] a sixth lens with negative focal power, whose object side surface is a concave surface;

[0010] a seventh lens with positive focal power, whose object side surface is a convex surface, and whose image side surface is a convex surface;

[0011] an eighth lens with focal power, whose image side surface is a concave surface near the optical axis;

[0012] Wherein, the aperture value Fno of the optical lens and the total optical length TTL of the optical lens satisfy: 0.13 / mm<Fno / TTL<0.19 / mm.

[0013] Further preferably, the real image height IH corresponding to the maximum field angle of view of the optical lens and the effective focal length f of the optical lens satisfy: 2.7<IH / f<3.

[0014] It is further preferred that the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -2.8 < f1 / f < -2.2.

[0015] It is further preferred that the effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: -1.5 < f12 / f < -1.

[0016] It is further preferred that the effective focal length f of the optical lens and the combined focal length f38 of the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: 1.1 < f38 / f < 1.9.

[0017] It is further preferred that the first lens object-side end half light entrance radius CSD11 and the sagitta SAGX11 corresponding to the first lens object-side end maximum half light entrance radius satisfy: 2.3 < CSD11 / SAGX11 < 3.

[0018] It is further preferred that the first lens object-side end half light entrance radius CSD11 and the eighth lens object-side end half light entrance radius CSD81 satisfy: 1.6 < CSD11 / CSD81 < 2.

[0019] It is further preferred that the focal length f1 of the first lens, the object-side surface curvature radius R1 of the first lens and the image-side surface curvature radius R2 of the first lens satisfy: -1.2 < f1 / (R1+R2) < -0.8.

[0020] It is further preferred that the maximum edge thickness value ETmax in the first lens to the eighth lens and the minimum edge thickness value ETmin in the first lens to the eighth lens satisfy: 5.2 < ETmax / ETmin < 7.5.

[0021] It is further preferred that the object-side surface curvature radius R1 of the first lens and the image-side surface curvature radius R2 of the first lens satisfy: 2 < (R1+R2) / (R1-R2) < 2.5.

[0022] Compared with the prior art, the optical lens provided by the application adopts eight lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages of miniaturization, large aperture, large field of view, small distortion, high imaging quality, etc. BRIEF DESCRIPTION OF DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0024] Figure 1 Structure diagram of the optical lens in Embodiment 1 of the present application.

[0025] Figure 2 Astigmatism curve of the optical lens in Embodiment 1 of the present application.

[0026] Figure 3 F-Theta distortion curve of the optical lens in Embodiment 1 of the present application.

[0027] Figure 4 Axial aberration curve of the optical lens in Embodiment 1 of the present application.

[0028] Figure 5 Vignetting curve of the optical lens in Embodiment 1 of the present application.

[0029] Figure 6 Structure diagram of the optical lens in Embodiment 2 of the present application.

[0030] Figure 7 Astigmatism curve of the optical lens in Embodiment 2 of the present application.

[0031] Figure 8 F-Theta distortion curve of the optical lens in Embodiment 2 of the present application.

[0032] Figure 9 Axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0033] Figure 10 Vignetting curve of the optical lens in Embodiment 2 of the present application.

[0034] Figure 11 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0035] Figure 12 Astigmatism curve of the optical lens in Embodiment 3 of the present application.

[0036] Figure 13 F-Theta distortion curve of the optical lens in Embodiment 3 of the present application.

[0037] Figure 14 Axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0038] Figure 15 Vignetting curve of the optical lens in Embodiment 3 of the present application.

[0039] Figure 16 Structure diagram of the optical lens in Embodiment 4 of the present application.

[0040] Figure 17A plot of astigmatism for the optical lens of Example 4 of the present application.

[0041] Figure 18 A plot of F-Theta distortion for the optical lens of Example 4 of the present application.

[0042] Figure 19 A plot of axial aberration for the optical lens of Example 4 of the present application.

[0043] Figure 20 A plot of lateral chromatic aberration for the optical lens of Example 4 of the present application.

[0044] Figure 21 A schematic diagram of the optical lens of Example 5 of the present application.

[0045] Figure 22 A plot of astigmatism for the optical lens of Example 5 of the present application.

[0046] Figure 23 A plot of F-Theta distortion for the optical lens of Example 5 of the present application.

[0047] Figure 24 A plot of axial aberration for the optical lens of Example 5 of the present application.

[0048] Figure 25 A plot of lateral chromatic aberration for the optical lens of Example 5 of the present application.

[0049] Figure 26 A schematic diagram of the optical lens of Example 6 of the present application.

[0050] Figure 27 A plot of astigmatism for the optical lens of Example 6 of the present application.

[0051] Figure 28 A plot of F-Theta distortion for the optical lens of Example 6 of the present application.

[0052] Figure 29 A plot of axial aberration for the optical lens of Example 6 of the present application.

[0053] Figure 30 A plot of lateral chromatic aberration for the optical lens of Example 6 of the present application.

[0054] The present application will be further described with reference to the following detailed description taken in conjunction with the above drawings. DETAILED DESCRIPTION

[0055] For a better understanding of the present application, various aspects of the present application will be presented in more detail by referring to the attached drawings. It should be understood that these detailed descriptions are merely descriptive of the embodiments of the present application and are not intended in any way to limit the scope of the present application. Throughout the specification, like drawing reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0056] It should be noted that the expressions first, second, third and the like in this specification are used only to distinguish one feature from another feature, and do not indicate any limitation of the features. Thus, the first lens discussed below can also be referred to as a second lens or a third lens without departing from the teachings of the present application.

[0057] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for the sake of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0058] In this specification, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the image plane is referred to as the image side surface of the lens.

[0059] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", when used in this specification, specify the presence of stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. Furthermore, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". Also, the word "exemplary" is intended to mean an example or an illustration.

[0060] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0061] It should be noted that the embodiments and the features in the embodiments in the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0062] The optical lens provided by the embodiment of the present application comprises eight lenses, which are sequentially arranged along the optical axis from the object side to the imaging surface and include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens.

[0063] In some embodiments, the first lens can have a negative focal power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface. The second lens can have a negative focal power, the object side surface of which is a concave surface, and the image side surface of which can be a concave surface or a convex surface. The third lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface. The fourth lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface. The fifth lens can have a positive focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which is a convex surface. The sixth lens can have a negative focal power, the object side surface of which is a concave surface, and the image side surface of which can be a concave surface or a convex surface. The seventh lens can have a positive focal power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface. The eighth lens can have a positive focal power or a negative focal power, the object side surface of which can be a concave surface or a convex surface, and the image side surface of which is a concave surface near the optical axis.

[0064] In some embodiments, the optical lens can further comprise a diaphragm, which can be located between the second lens and the third lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging.

[0065] In some embodiments, the optical lens can further comprise a filter, which is arranged between the eighth lens and the imaging surface. The filter is used to filter out interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0066] In some embodiments, the aperture value Fno of the optical lens and the total optical length TTL of the optical lens satisfy: 0.13 / mm<Fno / TTL<0.19 / mm. Satisfying the above condition formula, the optical lens can simultaneously meet the design requirements of large aperture and miniaturization, and at the same time provide sufficient light quantity for shooting, thereby meeting the needs of high-quality and high-definition shooting under dark light conditions.

[0067] In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.7<IH / f<3. Satisfying the above condition formula is conducive to realizing the large wide-angle characteristics of the optical lens, thereby meeting the demand for large range shooting, and also realizing the large image surface characteristics, thereby improving the imaging quality of the optical lens.

[0068] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -2.8 < f1 / f < -2.2. By satisfying the above condition, the first lens of the optical lens is set as a negative focal length lens, which can capture light rays at a large angle entering the optical lens, expand the field of view angle range of the optical lens, and reduce the sensitivity of the optical lens and realize the miniaturization design of the optical lens.

[0069] In some embodiments, the effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: -1.5 < f12 / f < -1. By satisfying the above condition, by reasonably allocating the focal length of the front lens group composed of the first lens and the second lens, the wide field of view angle object surface light can be converged into the lens, the distortion of the lens can be better corrected, and no large aberration is generated. At the same time, the front lens group has a suitable refractive power, which is beneficial to reducing the total length of the optical lens.

[0070] In some embodiments, the effective focal length f of the optical lens and the combined focal length f38 of the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: 1.1 < f38 / f < 1.9. By satisfying the above condition, by reasonably allocating the focal length of the rear lens group composed of the third lens to the eighth lens, the distortion and astigmatism generated by the front lens of the optical lens can be balanced, and the imaging quality of the optical lens can be improved.

[0071] In some embodiments, the first lens object side end light half aperture CSD11 and the corresponding sagittal height SAGX11 at the first lens object side end maximum light half aperture satisfy: 2.3 < CSD11 / SAGX11 < 3. By satisfying the above condition, the optical lens meets the small aperture design requirement, which is beneficial to compress the central field of view of the optical lens, so that the imaging quality of the edge field is better.

[0072] In some embodiments, the first lens object side end light half aperture CSD11 and the eighth lens object side end light half aperture CSD81 satisfy: 1.6 < CSD11 / CSD81 < 2. By satisfying the above condition, by controlling the ratio of the light half aperture of the first lens object side end and the light half aperture of the eighth lens object side end, the optical lens has a small aperture size, which is convenient for being carried on the unmanned aerial vehicle equipment. At the same time, the optical lens can realize large-angle light collection, realize large field of view angle imaging of the optical lens, increase the imaging area of the optical lens, and improve the imaging quality.

[0073] In some embodiments, the focal length f1 of the first lens, the object-side surface radius of curvature R1 of the first lens, and the image-side surface radius of curvature R2 of the first lens satisfy: -1.2 < f1 / (R1+R2) < -0.8. Satisfying the above condition formula can constrain the surface shape of the object-side surface and the image-side surface of the first lens, help to reduce the bending degree of light at the image-side surface of the first lens, reduce the astigmatism of the optical lens, balance the astigmatism problem brought by the large field of view of the optical lens, so that the optical lens has a large field of view and the astigmatism is not too large, and further ensure that the optical lens has excellent imaging quality.

[0074] In some embodiments, the maximum edge thickness value ETmax in the first lens to the eighth lens and the minimum edge thickness value ETmin in the first lens to the eighth lens satisfy: 5.2 < ETmax / ETmin < 7.5. Satisfying the above condition formula, in order to realize the miniaturized design of the optical lens, by controlling the ratio of the maximum edge thickness value in the eight lenses of the optical lens to the minimum edge thickness value in the eight lenses of the optical lens, the total length of the optical lens is reduced, and the distortion and aberration of the optical lens are also reduced, and the imaging quality of the optical lens can be improved.

[0075] In some embodiments, the object-side surface radius of curvature R1 of the first lens and the image-side surface radius of curvature R2 of the first lens satisfy: 2 < (R1+R2) / (R1-R2) < 2.5. Satisfying the above condition formula, by reasonably limiting the shape of the object-side surface and the image-side surface of the first lens, the distortion generated by the first lens can be reduced, the distortion correction difficulty of the subsequent lenses is reduced, and the imaging quality is improved.

[0076] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the center thicknesses of the first lens to the eighth lens along the optical axis satisfy: 1.3 < TTL / ∑CT < 1.4. Satisfying the above condition formula, reasonably configuring the total optical length of the optical lens and the sum of the thicknesses of the lenses helps to realize high-pixel characteristics and improve the imaging quality of the optical lens; at the same time, the total optical length of the optical lens can be effectively shortened to meet the miniaturization and lightweight design requirements.

[0077] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.6 < f2 / f < -2.2. Satisfying the above condition formula is conducive to cooperating with the first lens to make large-angle light incident into the optical lens, thereby expanding the field of view of the optical lens, and is also conducive to correcting the astigmatism and chromatic aberration of the optical lens, and improving the imaging quality of the optical lens.

[0078] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.9 < f3 / f < 2.2. By satisfying the above condition, by setting the third lens with positive refractive power and limiting the ratio of the focal length of the third lens to the effective focal length of the optical lens, the light ray trend from the first lens and the second lens is adjusted, so that the optical lens has the characteristics of large field of view, low sensitivity and miniaturization.

[0079] In some embodiments, the distance CT12 of 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 < 0.13. By satisfying the above condition, by reasonably limiting the air gap between the first lens and the second lens, the light deflection can be slowed down, which is beneficial to reduce the sensitivity of the optical lens.

[0080] In some embodiments, the sagittal height SAGX11 of the first lens at the maximum light passing half radius of the object side end and the central thickness CT1 of the first lens satisfy: 0.6 < SAGX11 / CT1 < 0.9. By satisfying the above condition, by 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 biased to be curved; meanwhile, the larger sagittal height is beneficial to the first lens to collect large field of view light, realize high angular resolution in the center of the optical lens, and further improve the imaging quality in the central region.

[0081] In some embodiments, the optical lens satisfies the condition: 1.2mm < f < 1.7mm, 8.2mm < TTL < 10.2mm, 1.4 < Fno < 1.6, 4mm < IH < 4.6mm, 165° < FOV < 185°, wherein f represents the effective focal length 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 real image height corresponding to the maximum field of view angle of the optical lens, and FOV represents the maximum field of view angle of the optical lens. By satisfying the above conditions, it is shown that the optical lens provided by the embodiments of the present application at least has the following characteristics: large aperture, which enables the lens to realize high-definition imaging in a dark environment; large field of view angle, which can have a large field of view; and short total length, which is beneficial to better realize the miniaturization of the device.

[0082] In some embodiments, the eight lenses in the optical lens can all be plastic lenses or adopt a glass-plastic hybrid material collocation structure. Preferably, the optical lens of the present application adopts an eight-lens glass-plastic hybrid collocation structure, which can improve the thermal stability. Specifically, the first lens and the fourth lens can be glass lenses, and the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens can all be plastic lenses. By adopting a glass-plastic hybrid structure, the cost can be effectively reduced, the aberration can be corrected, the volume can be reduced, and an optical lens product with higher cost performance can be provided.

[0083] In some embodiments, 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 can adopt a spherical lens or an aspherical lens. Compared with a spherical structure, an aspherical structure can effectively reduce aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better achieving miniaturization of the optical lens. More specifically, in the optical lens provided by the application, 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 all adopt an aspherical lens.

[0084] In various embodiments of the application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation:

[0085] ;

[0086] wherein z is the distance of the curved surface from the vertex of the curved surface in the direction of the optical axis, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the quadratic surface coefficient, and B, C, D, E, F, G and H are respectively the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order and sixteenth-order surface coefficients.

[0087] The application will be further described in the following embodiments. In various embodiments, the thickness, the radius of curvature and the material selection of each lens in the optical lens are different, and the specific differences can be referred to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, and any change, replacement, combination or simplification made without departing from the innovative points of the application should be regarded as equivalent replacement, and all are included in the protection scope of the application.

[0088] Embodiment 1

[0089] Please refer to Figure 1 , which is a structural schematic diagram of the optical lens 100 provided in the embodiment 1 of the application. The optical lens 100 includes, along the optical axis from the object side to the imaging surface S19, a first lens L1, a second lens L2, a diaphragm ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8 and a filter G1.

[0090] The first lens L1 has a negative focal length, the object side S1 thereof is a convex surface, and the image side S2 thereof is a concave surface.

[0091] The second lens L2 has a negative focal length, the object side S3 thereof is a concave surface, and the image side S4 thereof is a concave surface at the near optical axis.

[0092] The third lens L3 has positive refractive power, the object side S5 is a convex surface, and the image side S6 is a convex surface;

[0093] The fourth lens L4 has positive refractive power, the object side S7 is a convex surface, and the image side S8 is a convex surface;

[0094] The fifth lens L5 has positive refractive power, the object side S9 is a concave surface at the near optical axis, and the image side S10 is a convex surface;

[0095] The sixth lens L6 has negative refractive power, the object side S11 is a concave surface, and the image side S12 is a concave surface;

[0096] The seventh lens L7 has positive refractive power, the object side S13 is a convex surface, and the image side S14 is a convex surface;

[0097] The eighth lens L8 has positive refractive power, the object side S15 is a convex surface at the near optical axis, and the image side S16 is a concave surface at the near optical axis;

[0098] The object side S17 and the image side S18 of the filter G1 are both flat surfaces;

[0099] The imaging surface S19 is a flat surface.

[0100] The first lens L1 and the fourth lens L4 are glass aspherical lenses; the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are plastic aspherical lenses.

[0101] The related parameters of the lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0102] Table 1-1

[0103]

[0104] The surface type parameters of the aspherical lenses of the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0105] Table 1-2

[0106]

[0107] In this embodiment, the astigmatism curve, the F-Theta distortion curve, the axial aberration curve, and the transverse aberration curve of the optical lens 100 are shown in Figure 2 、 Figure 3 、 Figure 4 、 Figure 5

[0108] Figure 2 ​A curve diagram of astigmatism of the optical lens 100 in the embodiment is shown, which represents astigmatism of light rays on the sagittal image surface and the tangential image surface, the horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field angle (unit: °). As can be seen from the diagram, the astigmatism of the sagittal image surface and the tangential image surface is controlled within ±0.1 mm, which shows that the optical lens 100 can better correct astigmatism.

[0109] Figure 3 An F-Theta distortion curve of the optical lens 100 in the embodiment 1 is shown, which represents F-Theta distortion of light rays at different image heights on the imaging surface, the horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the diagram, the F-Theta distortion of the optical lens is controlled within ±10%, which shows that the optical lens 100 can better correct distortion.

[0110] Figure 4 An axial aberration curve diagram of the optical lens 100 in the embodiment is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the diagram, the offset of the axial aberration is controlled within ±0.02 mm, which shows that the optical lens 100 can better correct the axial aberration.

[0111] Figure 5 A curve diagram of the optical lens 100 in the embodiment is shown, which represents the aberration of each wavelength on the optical axis at the imaging surface, the horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. As can be seen from the diagram, the offset of the axial aberration is controlled within ±0.02 mm, which shows that the optical lens 100 can better correct the axial aberration.

[0112] Embodiment 2

[0113] Please refer to Figure 6 , which is a structural schematic diagram of the optical lens 200 provided in the embodiment 2 of the present application. Compared with the embodiment 1, the main difference is that the image side S4 of the second lens L2 is a convex surface; the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0114] The related parameters of each lens in the optical lens 200 in the embodiment 2 are shown in Table 2-1.

[0115] Table 2-1

[0116]

[0117] The surface type parameters of the aspheric lens of the optical lens 200 in the embodiment 2 are shown in Table 2-2.

[0118] Table 2-2

[0119]

[0120] In this embodiment, the astigmatism curve, F-Theta distortion curve, axial 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 astigmatism in the meridional and sagittal image planes is controlled within ±0.2mm, indicating that the optical lens 200 can effectively correct astigmatism. From Figure 8 As can be seen, the F-Theta distortion of the optical lens is controlled within -8% to 10%, indicating that the optical lens 200 can correct distortion well. From Figure 9 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens 200 can effectively correct axial aberration. From Figure 10 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 2μm, indicating that the optical lens 200 can correct chromatic aberration well.

[0122] Example 3

[0123] Please see Figure 11 The figure shows 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 object side surface S9 of the fifth lens L5 is a convex surface; the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0124] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0125] Table 3-1

[0126]

[0127] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0128] Table 3-2

[0129]

[0130] In this embodiment, the astigmatism curve, F-Theta distortion curve, axial 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.

[0131] As can be seen from Figure 12 , the image spread of the meridional image plane and the sagittal image plane is controlled within ±0.1mm, which shows that the optical lens 300 can correct the image spread well. As can be seen from Figure 13 , the F-Theta distortion of the optical lens is controlled within -7%~10%, which shows that the optical lens 300 can correct the distortion well. As can be seen from Figure 14 , the shift of the axial aberration is controlled within ±0.02mm, which shows that the optical lens 300 can correct the axial aberration well. As can be seen from Figure 15 , the transverse chromatic aberration of the longest wavelength and the shortest wavelength is controlled within -1μm~2μm, which shows that the optical lens 300 can correct the chromatic aberration well.

[0132] Embodiment 4

[0133] Please refer to Figure 16 , which is a structural schematic diagram of the optical lens 400 provided in the embodiment 4 of the present application. Compared with the embodiment 1, the main difference is that the optical parameters such as the radius of curvature of each lens surface and the lens thickness are different.

[0134] The related parameters of each lens in the optical lens 400 in the embodiment 4 are shown in Table 4-1.

[0135] Table 4-1

[0136]

[0137] The surface type parameters of the aspherical lens of the optical lens 400 in the embodiment 4 are shown in Table 4-2.

[0138] Table 4-2

[0139]

[0140] In the embodiment, the image spread curve, the F-Theta distortion curve, the axial aberration curve and the transverse chromatic aberration curve of the optical lens 400 are respectively shown in Figure 17 、 Figure 18 、 Figure 19 、 Figure 20 .

[0141] As can be seen from Figure 17 , the image spread of the meridional image plane and the sagittal image plane is controlled within ±0.2mm, which shows that the optical lens 400 can correct the image spread well. As can be seen from Figure 18 ​​​​​​As can be seen, the F-Theta distortion of the optical lens is controlled within ±10%, indicating that the optical lens 400 can correct distortion well. From Figure 19 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens 400 can effectively correct axial aberration. From Figure 20 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 2μm, indicating that the optical lens 400 can correct chromatic aberration well.

[0142] Example 5

[0143] Please see Figure 21 The figure shown is 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 optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0144] The relevant parameters of each lens in the optical lens 500 in Example 5 are shown in Table 5-1.

[0145] Table 5-1

[0146]

[0147] The surface profile parameters of the aspherical lens of the optical lens 500 in Example 5 are shown in Table 5-2.

[0148] Table 5-2

[0149]

[0150] In this embodiment, the astigmatism curve, F-Theta distortion curve, axial 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.

[0151] from Figure 22 As can be seen, the astigmatism in the meridional and sagittal image planes is controlled within -0.3mm to 0.1mm, indicating that the optical lens 500 can effectively correct astigmatism. From Figure 23 As can be seen, the F-Theta distortion of the optical lens is controlled within -8% to 12%, indicating that the optical lens 500 can correct distortion well. From Figure 24 As can be seen, the axial aberration offset is controlled within ±0.05mm, indicating that the optical lens 500 can effectively correct axial aberration. From Figure 25 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within 0~2μm, indicating that the optical lens 500 can correct chromatic aberration well.

[0152] Example 6

[0153] Please see Figure 26 The figure shown is a schematic diagram of the structure of the optical lens 600 provided in Embodiment 6 of the present invention. The main difference between this embodiment and Embodiment 1 is that: the eighth lens L8 has negative optical power; the image side S12 of the sixth lens L6 is a convex surface; the object side S15 of the eighth lens L8 is a concave surface; and 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 600 in Example 6 are shown in Table 6-1.

[0155] Table 6-1

[0156]

[0157] The surface profile parameters of the aspherical lens of the optical lens 600 in Example 6 are shown in Table 6-2.

[0158] Table 6-2

[0159]

[0160] In this embodiment, the astigmatism curve, F-Theta distortion curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens 600 are respectively as follows: Figure 27 , Figure 28 , Figure 29 , Figure 30 As shown.

[0161] from Figure 27 As can be seen, the astigmatism in the meridional and sagittal image planes is controlled within -0.2mm to 0.1mm, indicating that the 600mm optical lens can effectively correct astigmatism. Figure 28 As can be seen, the F-Theta distortion of the optical lens is controlled within -8% to 12%, indicating that the 600 optical lens can correct distortion well. From Figure 29 As can be seen, the axial aberration offset is controlled within ±0.03mm, indicating that the optical lens 600 can effectively correct axial aberration. From Figure 30 As can be seen, the chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 3μm, indicating that the optical lens 600 can correct chromatic aberration well.

[0162] Please refer to Table 7 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.

[0163] Table 7

[0164]

[0165] In summary, the optical lens provided by this invention employs an eight-element glass-plastic hybrid structure. Through specific surface shape settings and reasonable power distribution, the optical lens structure is relatively compact, effectively shortening the overall length of the optical lens and facilitating miniaturization. It features a large aperture, enabling high-definition imaging even in low-light environments. Simultaneously, it has a large field of view, providing a wide viewing area. Furthermore, it can effectively correct overall aberrations of the optical lens, exhibiting low distortion and high pixel count, thus improving the imaging quality of the optical lens.

[0166] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," and "some examples" 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.

[0167] 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, eight pieces of lenses in total, characterized in that, In order from the object side to the imaging plane along the optical axis, successively comprises: a first lens with negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens with negative refractive power, the object side surface of which is a concave surface; a third lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fourth lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fifth lens with positive refractive power, the image side surface of which is a convex surface; a sixth lens with negative refractive power, the object side surface of which is a concave surface; a seventh lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; an eighth lens with refractive power, the image side surface of which is a concave surface at the near optical axis; wherein the aperture value Fno of the optical lens and the total optical length TTL of the optical lens satisfy: 0.13 / mm<Fno / TTL<0.19 / mm, 1.4<Fno<1.6; the first lens object side end half light entrance diameter CSD11 and the corresponding sagitta SAGX11 at the first lens object side end maximum half light entrance diameter satisfy: 2.3<CSD11 / SAGX11<3.

2. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field angle of view of the optical lens and the effective focal length f of the optical lens satisfy: 2.7<IH / f<3.

3. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -2.8<f1 / f<-2.

2.

4. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: -1.5<f12 / f<-1.

5. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the combined focal length f38 of the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: 1.1<f38 / f<1.

9.

6. The optical lens of claim 1, wherein, the first lens object side end half light entrance diameter CSD11 and the eighth lens object side end half light entrance diameter CSD81 satisfy: 1.6<CSD11 / CSD81<2.

7. The optical lens of claim 1, wherein, the focal length f1 of the first lens, the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy: -1.2<f1 / (R1+R2)<-0.

8.

8. The optical lens of claim 1, wherein, the maximum edge thickness value ETmax in the first lens to the eighth lens and the minimum edge thickness value ETmin in the first lens to the eighth lens satisfy: 5.2<ETmax / ETmin<7.

5.

9. The optical lens of claim 1, wherein, the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy: 2<(R1+R2) / (R1-R2)<2.5.

Images