Optical lens

Abstract

The application provides an optical lens, which comprises six lenses in sequence from an object side to an imaging surface along an optical axis, and the six 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 convex surface, and the image side surface of the second lens is a concave surface; a third lens with positive optical power, wherein the object side surface and the image side surface of the third lens are both convex surfaces; a fourth lens with positive optical power, wherein the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; a fifth lens with negative optical power, wherein the object side surface and the image side surface of the fifth lens are both concave surfaces; and a sixth lens with positive optical power, wherein the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a concave surface; and the object side surface curvature radius R9 of the fifth lens and the image side surface curvature radius R10 of the fifth lens satisfy: -18 < R9 / R10 < -7. The optical lens provided by the application adopts six lenses with specific optical power, and 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 people's demands for driving experience continue to increase, automotive optical lenses are being used more and more in intelligent driving, and the status of automotive optical lenses in the automotive industry is constantly rising.

[0003] Advanced Driver Assistance Systems (ADAS) play a crucial role in intelligent driving. They use various lenses and sensors to collect environmental information to ensure driver safety. Existing ADAS lenses not only require a slim and compact design with high pixel count and high resolution, but also need to produce clear images at varying temperatures. Therefore, it is necessary to develop an optical lens with excellent imaging performance. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0005] The technical solution adopted in this invention is as follows:

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

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

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

[0009] A third lens with positive optical power has convex surfaces on both its object side and image side.

[0010] The fourth lens with positive optical power has a concave object side and a convex image side.

[0011] The fifth lens with negative optical power has concave object-side and image-side surfaces;

[0012] The sixth lens with positive optical power has a convex object-side surface and a concave image-side surface.

[0013] Wherein, the object-side radius of curvature R9 of the fifth lens and the image-side radius of curvature R10 of the fifth lens satisfy: -18 <R9 / R10<-7。

[0014] Further preferably, the maximum field of view (FOV) of the optical lens and the aperture value (FNO) satisfy: 45° <FOV / FNO<60°。

[0015] More preferably, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -3.8 < f2 / f < -2.5.

[0016] More preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.2 < f4 / f < 3.1.

[0017] More preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -1.5 < f5 / f < -0.7.

[0018] More preferably, the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: -14.5 < R9 / f < -6.2; the effective focal length f of the optical lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.5 < R10 / f < 1.1.

[0019] More preferably, the effective focal length f of the optical lens and the curvature radius R12 of the image side surface of the sixth lens satisfy: 3.5 < R12 / f < 5.5.

[0020] More preferably, the clear aperture semi-diameter d10 of the image side surface of the fifth lens and the sagittal height Sag10 of the clear aperture of the image side surface of the fifth lens satisfy: 0.25 < Sag10 / d10 < 0.45.

[0021] More preferably, the distance CT23 between the second lens and the third lens on the optical axis, the distance CT34 between the third lens and the fourth lens on the optical axis and the distance CT12 between the first lens and the second lens on the optical axis satisfy: 4.2 < (CT23 - CT34) / CT12 < 17.1.

[0022] More preferably, the distance CT23 between the second lens and the third lens on the optical axis and the focal length f2 of the second lens satisfy: -1.3 < CT23 / f2 < -0.8.

[0023] The optical lens provided by the present invention adopts six lenses with specific optical powers. 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 enhanced. At the same time, the optical lens has good imaging quality in both high and low temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

[0025] Figure 1 It is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 2 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 3 This is the F-Tanθ distortion curve of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 4 This is a chromatic aberration curve of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 5 This is an axial aberration curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 6 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of 25°C.

[0031] Figure 7 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of -25℃.

[0032] Figure 8 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of 70°C.

[0033] Figure 9 This is a relative illumination curve of the optical lens in Embodiment 1 of the present invention.

[0034] Figure 10 This is a schematic diagram of the optical lens structure in Embodiment 2 of the present invention.

[0035] Figure 11 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0036] Figure 12 This is the F-Tanθ distortion curve of the optical lens in Embodiment 2 of the present invention.

[0037] Figure 13 This is a chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0038] Figure 14 This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0039] Figure 15 This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of 25°C.

[0040] Figure 16 This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of -25℃.

[0041] Figure 17This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of 70°C.

[0042] Figure 18 This is a relative illumination curve of the optical lens in Embodiment 2 of the present invention.

[0043] Figure 19 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0044] Figure 20 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0045] Figure 21 This is the F-Tanθ distortion curve of the optical lens in Embodiment 3 of the present invention.

[0046] Figure 22 This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0047] Figure 23 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0048] Figure 24 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of 25°C.

[0049] Figure 25 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of -25℃.

[0050] Figure 26 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of 70°C.

[0051] Figure 27 This is a relative illumination curve of the optical lens in Embodiment 3 of the present invention.

[0052] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] The optical lens provided in this embodiment of the invention consists of six lenses, which are arranged sequentially from the object side to the imaging plane along the optical axis as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens.

[0061] In some embodiments, the first lens may have a negative optical power, with its object side being convex and its image side being concave. The second lens may have a negative optical power, with its object side being convex and its image side being concave. The third lens may have a positive optical power, with both its object side and image side being convex. The fourth lens may have a positive optical power, with its object side being concave and its image side being convex. The fifth lens may have a negative optical power, with both its object side and image side being concave. The sixth lens may have a positive optical power, with its object side being convex and its image side being concave.

[0062] In some embodiments, the optical lens may further include an aperture, which may be located between the second lens and the third lens. It can be understood that the aperture is used to limit the amount of incident light to change the brightness of the imaging. When the aperture is located between the second lens and the third lens, it is convenient for the correction of aperture aberration.

[0063] In some embodiments, the optical lens may further include a filter, which is disposed between the sixth 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.

[0064] In some embodiments, the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: -18 < R9 / R10 < -7. Meeting the above range is beneficial for the optical lens to have good imaging quality in high and low temperature environments.

[0065] In some embodiments, the maximum field of view FOV of the optical lens and the f-number FNO satisfy: 45° < FOV / FNO < 60°. Meeting the above range can achieve the balance of a large field of view and a large aperture.

[0066] In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -3.8 < f2 / f < -2.5. The effective focal length f of the optical lens and the radius of curvature R3 of the object side of the second lens satisfy: 5.8 < R3 / f < 17.6. Meeting the above range can share the negative optical power at the front end, avoid excessive light deflection caused by overly concentrated optical power, and reduce the difficulty of chromatic aberration correction of the optical lens.

[0067] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.2 < f4 / f < 3.1. Meeting the above range is beneficial for correcting axial aberration and 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 f5 of the fifth lens satisfy: -1.5 < f5 / f < -0.7. Meeting the above range is beneficial to increasing the imaging area of the optical lens and improving the imaging quality of the optical lens; at the same time, it is beneficial to the gentle trend of light rays, reducing the light deflection angle and reducing the generation of various off-axis aberrations.

[0069] In some embodiments, the effective focal length f of the optical lens and the curvature radius R9 of the object side surface of the fifth lens satisfy: -14.5 < R9 / f < -6.2; the effective focal length f of the optical lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.5 < R10 / f < 1.1. Meeting the above range can reasonably control the surface shape of the fifth lens, correct various aberrations of the optical lens, and improve the imaging quality of the optical lens.

[0070] In some embodiments, the effective focal length f of the optical lens and the curvature radius R12 of the image side surface of the sixth lens satisfy: 3.5 < R12 / f < 5.5. Meeting the above range helps to suppress the angle of incidence of the marginal field of view on the imaging surface, effectively transmit more light beams to the imaging surface, and improve the imaging quality.

[0071] In some embodiments, the clear aperture semi-diameter d10 of the image side surface of the fifth lens and the sagittal height Sag10 of the clear aperture of the image side surface of the fifth lens satisfy: 0.25 < Sag10 / d10 < 0.45. Meeting the above range can improve the relative illumination of the marginal field of view.

[0072] In some embodiments, the distance CT23 between the second lens and the third lens on the optical axis, the distance CT34 between the third lens and the fourth lens on the optical axis, and the distance CT12 between the first lens and the second lens on the optical axis satisfy: 4.2 < (CT23 - CT34) / CT12 < 17.1. Meeting the above range facilitates the realization of high-pixel characteristics and improves the imaging quality of the optical lens.

[0073] In some embodiments, the distance CT23 between the second lens and the third lens on the optical axis and the focal length f2 of the second lens satisfy: -1.3 < CT23 / f2 < -0.8. Meeting the above range can reasonably set the interval between the second lens and the third lens in the direction of the optical axis, improve the field curvature of the optical lens, reduce the difficulty of optimizing lens aberrations, and thus improve the lens imaging quality.

[0074] In some embodiments, the effective focal length f of the optical lens and the overall optical length TTL satisfy: 7.2 < TTL / f < 9.1. Meeting the above range controls the overall length within a reasonable range and leaves enough design space for each lens.

[0075] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the maximum field angle FOV of the optical lens satisfy: 0.6 < (IH / 2) / (f × Tan(FOV / 2)) < 0.7. Meeting the above range, the distortion is controlled within a reasonable range, improving the imaging quality.

[0076] In some embodiments, the effective focal length f of the optical lens and the back focal length BFL of the optical lens satisfy: 0.9 < BFL / f < 1.3. Meeting the above range, it is possible to maintain a long back focus, which is beneficial for adjusting the power distribution of each lens, so that there is more optimization space for various aberrations of the optical lens.

[0077] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: -6 < f1 / f < -2.1. Meeting the above range is beneficial for obtaining light rays incident at a large angle, enabling the optical lens to have the characteristic of a large field angle.

[0078] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.8 < f3 / f < 2.4. Meeting the above range is beneficial for correcting off-axis aberrations and improving the imaging quality of the optical lens.

[0079] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: 3.2 < f6 / f < 4.8. Meeting the above range is beneficial for balancing various aberrations and improving the imaging quality of the optical lens.

[0080] In some embodiments, the combined focal length f12 of the first lens and the second lens and the combined focal length f3456 of the third lens, the fourth lens, the fifth lens, and the sixth lens satisfy: -1.7 < f12 / f3456 < -0.9. Meeting the above range, the focal length distribution ratio of the lens groups at the front end and the rear end of the optical lens is close, which can reduce the design difficulty of the optical lens, reduce the correction difficulty of the axial aberration, and help maintain the consistency of the entire system.

[0081] In some embodiments, the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfy: 0.7 < (R9 + R10) / (R9 - R10) < 1.2. Meeting the above range is beneficial for balancing the axial aberration of the optical lens, and at the same time is beneficial for the smooth trend of light rays, and transferring as much edge field beam as possible to the rear end of the optical lens, improving the relative illumination of the optical lens.

[0082] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -2.6 < (R11 + R12) / (R11 - R12) < -1.3. Meeting the above range, while ensuring that the optical lens has a large field angle, the light deflection angle is reduced as much as possible, reducing the difficulty of aberration correction for the light rays from the edge field angle.

[0083] In some embodiments, the clear aperture semi-diameter d12 of the image side surface of the sixth lens and the sagittal height Sag12 of the clear aperture of the image side surface of the sixth lens satisfy: 2.5 < Sag12 / d12 < 3.5. Meeting the above range can improve the imaging quality of the edge field.

[0084] In some embodiments, the total optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens to the sixth lens along the optical axis respectively satisfy: 0.4 < ∑CT / TTL < 0.5. Meeting the above range and being restricted within a reasonable range can maintain the good processability of the lens and its reasonable arrangement within the system.

[0085] In some embodiments, the clear aperture semi-diameter d1 of the object side surface of the first lens, the true image height IH corresponding to the maximum field angle of the optical lens, and the maximum field angle FOV of the optical lens satisfy: 2 < d1 / (IH / 2) / tan(FOV / 2) < 3.1. Meeting the above range ensures the balance among the head size, field angle, and image plane of the optical lens.

[0086] In some embodiments, the optical lens satisfies the conditional formula: TTL < 36 mm, 3.2 mm < f < 4.5 mm, 90° < FOV < 110°, 5.5 mm < IH < 7 mm, 1.6 < Fno < 2.2, 12° < CRA < 23°, 3.2 mm < BFL < 5.5 mm, where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, IH represents the image height corresponding to the maximum field angle of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the chief ray angle of incidence of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has at least characteristics such as a large field angle and a large target surface.

[0087] In some embodiments, the lens material in the optical lens of the present invention can be glass or plastic. When the lens material is plastic, production costs can be effectively reduced. Conversely, when the lens material is glass, the low dispersion characteristic of glass itself can effectively correct geometric chromatic aberration of the optical system. More specifically, the first and third lenses in the optical lens provided by the present invention can be glass lenses, while the second, fourth, fifth, and sixth lenses can be plastic lenses, which can improve the imaging stability of the optical lens under different temperature environments while meeting high pixel requirements.

[0088] In some embodiments, the first, second, third, fourth, fifth, and sixth lenses can be spherical or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce aberrations in 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 can be spherical lenses, the second, fourth, and sixth lenses can be Q-type aspherical lenses, and the fifth lens can be an even-order aspherical lens.

[0089] 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:

[0090] Q of each lens bfs Type A aspherical lens satisfies the following equation:

[0091]

[0092] In the above equation, z represents the sag of the aspherical surface, and r is the radial coordinate of the aspherical surface. C bfs For the best-fit conic section, k is the quadratic surface constant, a m r is the aspherical surface shape coefficient of order m. n The maximum value of the normalized radius coordinates, u = r / r n Q m Q represents the m-th order. bfs Polynomial. Using Q bfs The advantage of polynomial representation of aspherical surfaces is that their surface structure is more stable, less prone to abrupt changes, and less likely to exhibit abnormal light patterns.

[0093] The even-order aspherical surface profiles of each lens satisfy the following equation:

[0094]

[0095] Where z is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis, c is the paraxial curvature of the surface, k is the quadratic surface coefficient, and A2i For the aspherical surface shape coefficient of the 2ith order.

[0096] 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.

[0097] Example 1

[0098] Please see Figure 1 The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane, the following components in sequence: a first lens L1, a second lens L2, an aperture ST, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a filter G1.

[0099] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0100] The second lens L2 has negative optical power, its object side S3 is convex, and its image side S4 is concave.

[0101] The third lens L3 has positive optical power, and its object side S5 and image side S6 are both convex surfaces.

[0102] The fourth lens L4 has positive optical power, its object side S7 is concave, and its image side S8 is convex.

[0103] The fifth lens L5 has negative optical power, and both its object side S9 and image side S10 are concave.

[0104] The sixth lens L6 has positive optical power, with its object-side surface S11 being convex and its image-side surface S12 being concave.

[0105] The object-side surface S13 and the image-side surface S14 of filter G1 are both planar.

[0106] The imaging plane S15 is a plane.

[0107] The first lens L1 and the third lens L3 are glass spherical lenses, the second lens L2, the fourth lens L4, and the sixth lens L6 are plastic Q-type aspherical lenses, and the fifth lens L5 is a plastic even-order aspherical lens.

[0108] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0109] Table 1-1

[0110]

[0111] The surface profile parameters of the Q-type aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0112] Table 1-2

[0113]

[0114]

[0115] The surface profile parameters of the even-order aspherical lens of the optical lens 100 in Example 1 are shown in Tables 1-3.

[0116] Table 1-3

[0117]

[0118] Figure 2 The field curvature curve of Example 1 is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within -0.01 mm to 0.03 mm, indicating that the optical lens can effectively correct the field curvature.

[0119] Figure 3 The F-Tanθ distortion curve of Example 1 is shown, which represents the F-Tanθ distortion of light at different image heights on the imaging plane. The horizontal axis represents the F-Tanθ distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-Tanθ distortion of the optical lens is controlled within -40% to 0, and the image compression in the edge angle region is relatively smooth, effectively improving the sharpness of the unfolded image.

[0120] Figure 4 The diagram shows the transverse chromatic aberration curves for Example 1, representing the chromatic aberration of each wavelength relative to the center wavelength (0.550 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 0–2 μm, indicating that the optical lens can excellently correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0121] Figure 5The axial aberration curve of Example 1 is shown, which represents the aberration of each wavelength on the optical axis at the imaging plane. 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 figure, the axial aberration offset is controlled within -0.01 mm to 0.02 mm, indicating that the optical lens can correct axial aberration well.

[0122] Figure 6 The diagram shows the MTF (Modulation Transfer Function) curve of Example 1 at an operating temperature of 25°C. It represents the lens imaging modulation at different spatial frequencies within each field of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.3 across the entire field of view. Within the range of 0–300 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, exhibiting good image quality and detail resolution even at room temperature.

[0123] Figure 7 The diagram shows the MTF (Modulation Transfer Function) curve of Example 1 at an operating temperature of -25°C. It represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.4 across the entire field of view. Within the range of 0–300 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, demonstrating good image quality and detail resolution even at low temperatures.

[0124] Figure 8 The diagram shows the MTF (Modulation Transfer Function) curve of Example 1 at an operating temperature of 70°C. It represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.35 across the entire field of view. Within the range of 0–300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good image quality and detail resolution even at higher temperatures.

[0125] Figure 9 The relative illumination curves for Example 1 are shown, representing the relative illumination values ​​at different field-of-view angles on the imaging plane. The horizontal axis represents the half-field angle (unit: °), and the vertical axis represents the relative illumination (unit: %). As can be seen from the figure, the relative illumination value of the optical lens is still greater than 80% at the maximum half-field angle, indicating that the optical lens has good relative illumination.

[0126] Example 2

[0127] Please see Figure 10The 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.

[0128] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0129] Table 2-1

[0130]

[0131]

[0132] The surface profile parameters of the Q-type aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0133] Table 2-2

[0134]

[0135] The surface profile parameters of the even-order aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-3.

[0136] Table 2-3

[0137]

[0138] from Figure 11 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.01mm to 0.02mm, indicating that the optical lens can effectively correct the field curvature.

[0139] from Figure 12 As can be seen, the F-Tanθ distortion of the optical lens is controlled within -40% to 0, and the image compression in the edge angle area is relatively smooth, which effectively improves the clarity of the unfolded image.

[0140] from Figure 13 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 can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0141] from Figure 14 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0142] from Figure 15As can be seen, in this embodiment, the MTF value is above 0.48 throughout the entire field of view at an operating temperature of 25℃. Within the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution under normal temperature conditions.

[0143] from Figure 16 As can be seen, in this embodiment, the MTF value is above 0.4 in the entire field of view when the working temperature is -25℃. In the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution even at low temperatures.

[0144] from Figure 17 As can be seen, in this embodiment, the MTF value is above 0.38 throughout the entire field of view at an operating temperature of 70℃. Within the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution even at higher temperatures.

[0145] from Figure 18 As can be seen, the relative illumination value of the optical lens is still greater than 80% at the maximum half field of view, indicating that the optical lens has good relative illumination.

[0146] Example 3

[0147] Please see Figure 19 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.

[0148] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0149] Table 3-1

[0150]

[0151]

[0152] The surface profile parameters of the Q-type aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0153] Table 3-2

[0154]

[0155] The surface profile parameters of the even-order aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-3.

[0156] Table 3-3

[0157]

[0158] from Figure 20 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.01mm to 0.02mm, indicating that the optical lens can effectively correct the field curvature.

[0159] from Figure 21 As can be seen, the F-Tanθ distortion of the optical lens is controlled within -35% to 0, and the image compression in the edge angle area is relatively smooth, which effectively improves the clarity of the unfolded image.

[0160] from Figure 22 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within 0 to 2 μm, indicating that the optical lens can effectively correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0161] from Figure 23 As can be seen, the axial aberration offset is controlled within -0.01mm to 0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0162] from Figure 24 As can be seen, in this embodiment, the MTF value is above 0.4 throughout the entire field of view at an operating temperature of 25℃. Within the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution under normal temperature conditions.

[0163] from Figure 25 As can be seen, in this embodiment, the MTF value is above 0.4 in the entire field of view when the working temperature is -25℃. In the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution even at low temperatures.

[0164] from Figure 26 As can be seen, in this embodiment, the MTF value is above 0.4 throughout the entire field of view at an operating temperature of 70℃. Within the range of 0 to 300 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution even at higher temperatures.

[0165] from Figure 27 As can be seen, the relative illumination value of the optical lens is still greater than 75% at the maximum half field of view, indicating that the optical lens has good relative illumination.

[0166] Please refer to Table 4 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, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0167] Table 4

[0168]

[0169]

[0170] In summary, the optical lens provided by this invention employs six lenses with specific optical powers. Through specific surface shape combinations and reasonable optical power allocation, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the overall image quality. Furthermore, the optical lens exhibits good imaging quality under both high and low temperature conditions.

[0171] 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.

[0172] 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, six pieces of lenses in total, characterized in that, In order from the object side to the imaging surface along the optical axis, successively comprise: a first lens with negative focal length, the object side is convex, the image side is concave; a second lens with negative focal length, the object side is convex, the image side is concave; a third lens with positive focal length, the object side and the image side are both convex; a fourth lens with positive focal length, the object side is concave, the image side is convex; a fifth lens with negative focal length, the object side and the image side are both concave; a sixth lens with positive focal length, the object side is convex, the image side is concave; Wherein, the object side curvature radius R9 of the fifth lens and the image side curvature radius R10 of the fifth lens satisfy: -18 < R9 / R10 < -7; The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -1.5 < f5 / f < -0.

7.

2. The optical lens of claim 1, wherein, The maximum field angle FOV of the optical lens and the aperture value FNO satisfy: 45° < FOV / FNO < 60°.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: -3.8 < f2 / f < -2.

5.

4. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: 2.2 < f4 / f < 3.

1.

5. The optical lens of claim 1, wherein, The object side curvature radius R9 of the fifth lens and the image side curvature radius R10 of the fifth lens satisfy: -15.74 ≤ R9 / R10 ≤ -7.56; The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: -1.27 ≤ f5 / f ≤ -1.

18.

6. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the object side curvature radius R9 of the fifth lens satisfy: -14.5 < R9 / f < -6.2; the effective focal length f of the optical lens and the image side curvature radius R10 of the fifth lens satisfy: 0.5 < R10 / f < 1.

1.

7. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and the image side curvature radius R12 of the sixth lens satisfy: 3.5 < R12 / f < 5.

5.

8. The optical lens of claim 1, wherein, The image side half light entrance radius d10 of the fifth lens and the image side half light entrance radius sag10 of the fifth lens satisfy: 0.25 < sag10 / d10 < 0.

45.

9. The optical lens of claim 1, wherein, The distance CT23 of the second lens and the third lens on the optical axis, the distance CT34 of the third lens and the fourth lens on the optical axis, and the distance CT12 of the first lens and the second lens on the optical axis satisfy: 4.2 < (CT23-CT34) / CT12 < 17.

1.

10. The optical lens of claim 1, wherein, The distance CT23 of the second lens and the third lens on the optical axis and the focal length f2 of the second lens satisfy: -1.3 < CT23 / f2 < -0.8.

Images