Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses arranged along an optical axis from an object side to an imaging surface in sequence, wherein the first lens has a negative focal length, the object side of the first lens is a convex surface, and the image side of the first lens is a concave surface; the second lens has a negative focal length, the object side of the second lens is a convex surface, and the image side of the second lens is a concave surface; the third lens has a positive focal length, the object side of the third lens is a convex surface, and the image side of the third lens is a convex surface; the fourth lens has a positive focal length, the object side of the fourth lens is a concave surface, and the image side of the fourth lens is a convex surface; the fifth lens has a positive focal length, the object side of the fifth lens is a convex surface, and the image side of the fifth lens is a convex surface; the sixth lens has a negative focal length, the object side of the sixth lens is a concave surface, and the image side of the sixth lens is a concave surface; and the seventh lens has a positive focal length, the object side of the seventh lens is a concave surface, and the image side of the seventh lens is a convex surface. The application realizes the effects of a super large field of view, a large aperture and miniaturization by reasonably matching the lens shapes and the focal length combinations of the lenses.

Description

Technical Field

[0001] This invention relates to the field of imaging lens technology, 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. However, some existing ADAS systems use wide-angle lenses, which suffer from significant aberrations, large field curvature, and poor image quality, failing to meet user needs. Therefore, there is a need to develop an optical lens with superior imaging performance. Summary of the Invention

[0004] In view of the above problems, the purpose of this invention is to provide an optical lens that can solve at least one or more of the above problems.

[0005] To achieve the above objectives, the present invention provides an optical lens comprising seven lenses, arranged sequentially along the optical axis from the object side to the image plane: a first lens with negative optical power, the object side of which is convex and the image side of which is concave; a second lens with negative optical power, the object side of which is convex and the image side of which is concave; a third lens with positive optical power, the object side of which is convex and the image side of which is convex; a fourth lens with positive optical power, the object side of which is concave and the image side of which is convex; a fifth lens with positive optical power, the object side of which is convex and the image side of which is convex; a sixth lens with negative optical power, the object side of which is concave and the image side of which is concave; and a seventh lens with positive optical power, the object side of which is concave and the image side of which is convex.

[0006] In some embodiments, the fifth lens and the sixth lens are cemented together to form a cemented lens.

[0007] In some implementations, the aperture stop is positioned between the fourth lens and the fifth lens.

[0008] In some implementations, the maximum field of view (FOV) of the optical lens and the aperture value (FNO) of the optical lens satisfy the following condition: 100° < FOV / FNO < 130°.

[0009] In some implementations, the total optical length (TTL) of the optical lens and the effective focal length (f) of the optical lens satisfy the condition: 10.0 < TTL / f < 15.0.

[0010] In some implementations, the image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view of the optical lens satisfy: 0.95 < (IH / 2) / (f×θ) < 1.10.

[0011] In some implementations, the optical back focal length (BFL) of the optical lens and the effective focal length (f) of the optical lens satisfy the condition: 1.8 < BFL / f < 2.5.

[0012] In some implementations, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: f1 / f < -5.0.

[0013] In some implementations, the effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.5 < f2 / f < -2.5.

[0014] In some implementations, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 5.0 < f3 / f.

[0015] In some implementations, the effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 6.0 < f4 / f.

[0016] In some implementations, the effective focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy the condition: 3.0 < f7 / f < 5.0.

[0017] In some embodiments, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.50 < (R3-R4) / (R3+R4) < 0.95.

[0018] In some embodiments, the radius of curvature R7 of the object side of the fourth lens and the radius of curvature R8 of the image side of the fourth lens satisfy: 0.10 < (R7-R8) / (R7+R8) < 0.50.

[0019] In some embodiments, the radius of curvature R13 of the object side of the seventh lens and the radius of curvature R14 of the image side of the seventh lens satisfy: 0.60 < (R13-R14) / (R13+R14) < 0.99.

[0020] In some embodiments, the sum of the center thicknesses of the first to seventh lenses, ∑CT, satisfies the condition that the total optical length of the optical lens, TTL, is 0.50 < ∑CT / TTL < 0.60.

[0021] In some embodiments, the object-side half-aperture sagitta Sag7 of the fourth lens and the object-side half-aperture sagitta d7 of the fourth lens, and the image-side half-aperture sagitta Sag8 of the fourth lens and the image-side half-aperture sagitta d8 of the fourth lens, respectively satisfy: -0.3 <Sag7 / d7<-0.2;-0.4<Sag8 / d8<-0.2。

[0022] In some embodiments, the object-side half-aperture sagitta Sag13 of the seventh lens and the object-side half-aperture sagitta d13 of the seventh lens, and the image-side half-aperture sagitta Sag14 of the seventh lens and the image-side half-aperture sagitta d14 of the seventh lens, respectively satisfy: -0.20 <Sag13 / d13<0;-0.6<Sag14 / d14<-0.3。

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: The optical lens provided by the present invention uses seven lenses with optical power. By reasonably matching the optical power and surface shape of each lens, the optical lens has a compact structure and good image quality. At the same time, by reasonably setting the aperture position, lens thickness and inter-lens spacing, the optical lens has an ultra-large field of view and a large aperture, achieving a balance between ultra-large field of view, large aperture, miniaturization and high pixel count, which can meet the imaging requirements of automotive lenses. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the optical lens in Embodiment 1 of the present invention.

[0025] Figure 2 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0026] Figure 3 This is a distortion curve of the optical lens in Embodiment 1 of the present invention.

[0027] Figure 4 This is a relative illumination curve of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 5 This is an MTF curve of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 6 This is a schematic diagram of the optical lens structure of Embodiment 2 of the present invention.

[0030] Figure 7 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0031] Figure 8 This is a distortion curve of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 9This is a relative illumination curve of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 10 This is the MTF curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 11 This is a schematic diagram of the optical lens structure of Embodiment 3 of the present invention.

[0035] Figure 12 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 13 This is a distortion curve of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 14 This is a relative illumination curve of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 15 This is an MTF curve of the optical lens in Embodiment 3 of the present invention.

[0039] Figure 16 This is a schematic diagram of the optical lens structure of Embodiment 4 of the present invention.

[0040] Figure 17 This is a field curvature curve diagram of the optical lens in Embodiment 4 of the present invention.

[0041] Figure 18 This is a distortion curve diagram of the optical lens in Embodiment 4 of the present invention.

[0042] Figure 19 This is a relative illumination curve of the optical lens in Embodiment 4 of the present invention.

[0043] Figure 20 This is the MTF curve of the optical lens in Embodiment 4 of the present invention. Detailed Implementation

[0044] To better understand the invention, various aspects of the invention 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 the invention and are not intended to limit the scope of the invention 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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 the invention, the word "may" is used to mean "one or more embodiments of the invention." And the term "exemplary" is intended to refer to an example or illustration.

[0049] 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 invention 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 defined herein.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] This invention provides an optical lens, which, from the object side to the imaging plane, includes, in sequence: a first lens, a second lens, a third lens, a fourth lens, an aperture stop, a fifth lens, a sixth lens, a seventh lens, and a filter, and the optical centers of each lens are located on the same straight line.

[0052] In some embodiments, the first lens is configured to have negative optical power, with the object side being convex and the image side being concave. This allows for the acquisition of as much large-angle incident light as possible, expanding the field of view of the optical lens. At the same time, it can reduce the tendency of light to bend, reduce the difficulty of aberration correction by subsequent lenses, and improve the imaging quality of the optical lens.

[0053] In some embodiments, the second lens is configured to have negative optical power, with the object side being convex and the image side being concave. This can effectively constrain large-angle light rays passing through the first lens, slow down the light refracting trend and make it transition smoothly, while also balancing the aberrations generated by the first lens and reducing the sensitivity of the optical lens.

[0054] In some embodiments, the third lens is configured to have positive optical power and a convex object side and an convex image side, which can converge the light rays passing through the second lens, further reduce the light refracting trend and make the transition smooth, while also correcting off-axis aberrations.

[0055] In some embodiments, the fourth lens is configured to have positive optical power, with the object side being concave and the image side being convex. This can further converge the light rays, reduce the light beam height, and make the light path transition smoothly. At the same time, it can balance the spherical aberration and field curvature generated by the front lens, thereby improving the imaging quality of the optical lens.

[0056] In some embodiments, the fifth lens and the sixth lens can be cemented together to form a cemented lens, which is used to share the chromatic aberration correction of the optical lens and improve the resolution of the optical lens. The fifth lens is configured to have positive optical power and a convex object side and a convex image side, while the sixth lens is configured to have negative optical power and a concave object side and a concave image side. This can converge the light rays emitted from the fourth lens and make them transition smoothly. At the same time, it can correct various aberrations caused by the front lens, reduce the loss of light in each field of view, improve the relative illumination of each field of view, and thus improve the imaging quality of the optical lens.

[0057] In some embodiments, the seventh lens is configured to have positive optical power, with the object side being concave and the image side being convex. This can effectively suppress the angle at which the edge field of view is incident on the imaging plane, effectively transmit more light beams to the imaging plane, and at the same time balance various aberrations of the optical lens, thereby improving the imaging quality of the optical lens.

[0058] In some embodiments, the aperture stop can be positioned between the fourth and fifth lenses to narrow the range of light emitted from the front lens, reduce the aperture of the rear lens, and balance the structure of the front and rear lens groups.

[0059] In some implementations, the aperture value FNO of the optical lens satisfies the following condition: 1.50 < FNO < 1.90. Meeting this range is beneficial for achieving large aperture characteristics, ensuring image clarity even in low-light environments or at night.

[0060] In some implementations, the maximum field of view (FOV) of the optical lens satisfies: 200° < FOV. Meeting this range facilitates the achievement of ultra-wide-angle characteristics, thereby enabling the acquisition of more scene information and meeting the needs of large-area detection.

[0061] In some implementations, the angle of incidence (CRA) of the principal ray at the maximum field of view of the optical lens on the image plane satisfies: 15° < CRA < 25°. Meeting this range allows for a larger tolerance range between the CRA of the optical lens and the CRA of the image sensor, improving the optical lens's adaptability to image sensors.

[0062] In some implementations, the maximum field of view (FOV) of the optical lens and the aperture value (FNO) of the optical lens satisfy the following condition: 100° < FOV / FNO < 130°. Meeting this range helps to expand the field of view and increase the aperture of the optical lens, achieving ultra-wide-angle and large-aperture characteristics. The ultra-wide-angle characteristic allows the optical lens to acquire more scene information, meeting the needs of large-area detection. The large aperture characteristic helps to mitigate the problem of rapid brightness decrease at the edges of the field of view caused by wide-angle lenses, thus also facilitating the acquisition of more scene information.

[0063] In some implementations, the total optical length (TTL) of the optical lens and the effective focal length (f) of the optical lens satisfy the condition: 10.0 < TTL / f < 15.0. Meeting this range can effectively limit the length and volume of the optical lens, enabling miniaturization of the optical lens.

[0064] In some implementations, the image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view of the optical lens satisfy: 0.95 < (IH / 2) / (f×θ) < 1.10. Meeting the above range can balance the needs of large-area detection and high-quality imaging, and improve the adaptability of the optical lens.

[0065] In some implementations, the optical back focal length (BFL) of the optical lens and the effective focal length (f) of the optical lens satisfy the condition: 1.8 < BFL / f < 2.5. Meeting this range allows the optical lens to have a longer optical back focal length, which is beneficial for the assembly of the optical lens.

[0066] In some embodiments, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: f1 / f < -5.0. Satisfying this range allows the first lens to have appropriate negative optical power, which helps to make the change in the refraction angle of the incident light more gradual, avoids excessive refraction changes that would produce too many aberrations, and at the same time helps more light to enter the rear lens, increasing the field of view of the optical lens and improving the relative illumination of the optical lens.

[0067] In some embodiments, the effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.5 < f2 / f < -2.5; the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.50 < (R3-R4) / (R3+R4) < 0.95. Meeting these ranges allows for a reasonable setting of the focal length and surface shape of the second lens, which helps to share some of the negative optical power, reducing the pressure on the negative optical power of the first lens. It also helps to converge edge field rays, preventing excessive light deflection angles so that the light can transition smoothly, and helps to correct aberrations caused by light passing through the first lens, thereby improving the imaging quality of the optical lens.

[0068] In some implementations, the effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 5.0 < f3 / f. Satisfying the above range allows the third lens to have appropriate positive optical power, which helps to slow down the trend of light reversal and make it transition smoothly. At the same time, it helps to reduce the spherical aberration generated by the front lens and improve the imaging quality of the optical lens.

[0069] In some embodiments, the effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 6.0 < f4 / f; the radius of curvature R7 of the object side of the fourth lens and the radius of curvature R8 of the image side of the fourth lens satisfy: 0.10 < (R7-R8) / (R7+R8) < 0.50. Meeting these ranges allows the fourth lens to have appropriate positive optical power and surface shape, which helps to mitigate the tendency of light rays to bend and reduce the height of light rays, resulting in a smooth transition of light paths. It also helps to reduce the difficulty of correcting spherical aberration and field curvature, thereby improving the imaging quality of the optical lens.

[0070] In some embodiments, the effective focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 3.0 < f7 / f < 5.0; the radius of curvature R13 of the object side of the seventh lens and the radius of curvature R14 of the image side of the seventh lens satisfy: 0.60 < (R13-R14) / (R13+R14) < 0.99. Meeting these ranges allows the seventh lens to have appropriate positive optical power and surface shape, which is beneficial for suppressing the angle of incidence of edge fields onto the imaging plane, while also balancing various aberrations of the optical lens and improving the imaging quality of the optical lens.

[0071] In some embodiments, the sum of the central thicknesses ∑CT of each of the first lens to the seventh lens and the total optical length TTL of the optical lens satisfy: 0.50 < ∑CT / TTL < 0.60. Meeting the above range is beneficial to compressing the total length and volume of the optical lens and maintaining the miniaturization of the optical lens.

[0072] In some embodiments, the sagittal height Sag7 of the object-side clear aperture of the fourth lens and the clear aperture diameter d7 of the object-side clear aperture of the fourth lens, and the sagittal height Sag8 of the image-side clear aperture of the fourth lens and the clear aperture diameter d8 of the image-side clear aperture of the fourth lens respectively satisfy: -0.3 < Sag7 / d7 < -0.2; -0.4 < Sag8 / d8 < -0.2. Meeting the above range can make the fourth lens have a meniscus shape concave toward the object side, with low requirements for the distance of incident light rays from the optical axis, which is beneficial to the smooth transition of light rays in the lens; at the same time, the marginal field light rays are deflected toward the optical axis direction after passing through the image side of the fourth lens, which is beneficial to reducing the rear port diameter of the optical lens.

[0073] In some embodiments, the sagittal height Sag13 of the object-side clear aperture of the seventh lens and the clear aperture diameter d13 of the object-side clear aperture of the seventh lens, and the sagittal height Sag14 of the image-side clear aperture of the seventh lens and the clear aperture diameter d14 of the image-side clear aperture of the seventh lens respectively satisfy: -0.20 < Sag13 / d13 < 0; -0.6 < Sag14 / d14 < -0.3. Meeting the above range can make the seventh lens have a meniscus shape concave toward the object side, which is beneficial to slowing down the light ray trend at the rear end of the lens, achieving a long back focal length BFL, and being able to disperse the central light rays and marginal light rays of each field, increasing the illuminance of the optical lens, and at the same time facilitating the correction of the aberration of the marginal light rays and central light rays to achieve high resolution. At the same time, it can make the angle of the light rays to the image plane meet the CRA requirements, achieve a small CRA, and improve the resolution and illuminance.

[0074] As an embodiment, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can be made of all-glass lenses or a combination of glass and plastic, and both can achieve good imaging effects. In this application, in order to further reduce the influence of high and low temperature environments on the lens, a seven-piece all-glass lens structure is adopted.

[0075] As an embodiment, at least one of the object side or the image side of the first lens, the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens is an aspherical surface. The characteristics of an aspherical lens are that the curvature changes continuously from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality.

[0076] To achieve better optical performance, the lens employs multiple aspherical lenses, and the shapes of each aspherical surface of the optical lens satisfy the following equation:

[0077]

[0078] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and A, B, C, D, E, and F are the second, fourth, sixth, eighth, tenth, and twelfth order surface coefficients, respectively.

[0079] 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.

[0080] Example 1

[0081] Please see Figure 1 The diagram shows a schematic of the structure of an optical lens provided in Embodiment 1 of the present invention. The optical lens includes, along the optical axis from the object side to the imaging plane S16, the following components in sequence: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, and a filter G1.

[0082] Among them, the first lens L1 is a glass spherical lens with negative optical power, its object-side surface S1 is convex, and its image-side surface S2 is concave; the second lens L2 is a glass spherical lens with negative optical power, its object-side surface S3 is convex, and its image-side surface S4 is concave; the third lens L3 is a glass spherical lens with positive optical power, its object-side surface S5 is convex, and its image-side surface S6 is convex; the fourth lens L4 is a glass spherical lens with positive optical power, its object-side surface S7 is concave, and its image-side surface S8 is convex; the fifth lens L5 is a glass spherical lens with positive optical power. A glass spherical lens with positive optical power has a convex object-side surface S9 and a convex image-side surface; the sixth lens L6 is a glass spherical lens with negative optical power, with a concave object-side surface S11 and a concave image-side surface S12, and the fifth lens L5 and the sixth lens L6 are cemented together to form a cemented lens, with the cementing surface S10; the seventh lens L7 is a glass aspherical lens with positive optical power, with a concave object-side surface S12 near the optical axis and a convex image-side surface S13; the filter G1 has a flat object-side surface S14 and an image-side surface S15.

[0083] The relevant parameters of each lens in the optical lens of Example 1 are shown in Table 1-1.

[0084] Table 1-1

[0085]

[0086]

[0087] The surface coefficients of the aspherical lens in the optical lens of Example 1 are shown in Table 1-2.

[0088] Table 1-2

[0089]

[0090] 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 ±0.04 mm, indicating that the optical lens can correct the field curvature very well.

[0091] Figure 3 The distortion curve of Example 1 is shown, which represents the F-θ distortion at different field-of-view angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the distortion value is controlled within ±2%, indicating that the optical lens can correct distortion very well.

[0092] Figure 4 The relative illumination curve of Example 1 is shown, which represents the relative illumination value 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 50% at the maximum half-field angle, indicating that the optical lens has good relative illumination.

[0093] Figure 5 The modulation transfer function (MTF) curve of Example 1 is shown, which represents the lens imaging modulation at different spatial frequencies in each field of view. The horizontal axis represents the 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 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, exhibiting good imaging quality and good detail resolution at both low and high frequencies.

[0094] Example 2

[0095] Please see Figure 6The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 2 of the present invention. The structure of the optical lens in this embodiment is roughly the same as that of the optical lens in Embodiment 1 above. The main difference is that the curvature radius, aspherical coefficient and thickness of each lens surface are different.

[0096] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2-1.

[0097] Table 2-1

[0098]

[0099] The surface coefficients of the aspherical lens in the optical lens of Example 2 are shown in Table 2-2.

[0100] Table 2-2

[0101]

[0102] Figures 7 to 10 The field curvature curve, distortion curve, relative illumination curve, and modulation transfer function (MTF) curve for Example 2 are shown respectively. As can be seen from the figures, the field curvature of the meridional and sagittal image planes is controlled within ±0.04 mm, indicating that the optical lens can effectively correct field curvature; the distortion value is controlled within ±2%, indicating that the optical lens can effectively correct distortion; the relative illumination value of the optical lens is still greater than 50% at the maximum half-field angle, indicating that the optical lens has good relative illumination; the MTF value of the optical lens is above 0.3 throughout the entire field of view, and within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution at both low and high frequencies.

[0103] Example 3

[0104] Please see Figure 11 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 3 of the present invention. The structure of the optical lens in this embodiment is roughly the same as that of the optical lens in Embodiment 1 above. The main difference is that the curvature radius, aspherical coefficient and thickness of each lens surface are different.

[0105] The relevant parameters of each lens in the optical lens of Example 3 are shown in Table 3-1.

[0106] Table 3-1

[0107]

[0108] The surface coefficients of the aspherical lens in Example 3 are shown in Table 3-2.

[0109] Table 3-2

[0110]

[0111] Figures 12 to 15 The field curvature curve, distortion curve, relative illumination curve, and modulation transfer function (MTF) curve of Example 3 are shown respectively. As can be seen from the figures, the field curvature of the meridional and sagittal image planes is controlled within ±0.04 mm, indicating that the optical lens can effectively correct field curvature; the distortion value is controlled within ±2%, indicating that the optical lens can effectively correct distortion; the relative illumination value of the optical lens is still greater than 50% at the maximum half-field angle, indicating that the optical lens has good relative illumination; the MTF value of the optical lens is above 0.3 throughout the entire field of view, and within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, demonstrating good imaging quality and good detail resolution at both low and high frequencies.

[0112] Example 4

[0113] Please see Figure 16 The figure shows a schematic diagram of the structure of the optical lens provided in Embodiment 4 of the present invention. The structure of the optical lens in this embodiment is roughly the same as that of the optical lens in Embodiment 1 above. The main difference is that the curvature radius, aspherical coefficient and thickness of each lens surface are different.

[0114] The relevant parameters of each lens in the optical lens of Example 4 are shown in Table 4-1.

[0115] Table 4-1

[0116]

[0117] The surface coefficients of the aspherical lens in Example 4 are shown in Table 4-2.

[0118] Table 4-2

[0119]

[0120] Figures 17 to 20The field curvature curve, distortion curve, relative illumination curve, and modulation transfer function (MTF) curve for Example 4 are shown respectively. As can be seen from the figures, the field curvature of the meridional and sagittal image planes is controlled within ±0.04 mm, indicating that the optical lens can correct field curvature very well; the distortion value is controlled within ±10%, indicating that the optical lens can correct distortion well; the relative illumination value of the optical lens is still greater than 50% at the maximum half-field angle, indicating that the optical lens has good relative illumination; the MTF value of the optical lens is above 0.3 throughout the entire field of view, and within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, exhibiting good imaging quality and good detail resolution at both low and high frequencies.

[0121] Please refer to Table 5, which shows the optical characteristics corresponding to the four embodiments above, including the effective focal length f of the optical lens, the maximum field of view FOV, the entrance pupil diameter EPD, the total optical length TTL, the aperture value FNO, the image height IH corresponding to the maximum field of view, the incident angle CRA of the principal ray on the image plane at the maximum field of view, and the values ​​corresponding to each conditional expression in each embodiment.

[0122] Table 5

[0123]

[0124]

[0125] In summary, the optical lens in this embodiment of the invention, by reasonably allocating the optical power of each lens, reasonably matching the surface shape of each lens, and reasonably setting the thickness of each lens and the spacing between each lens, and by adopting a combination structure of six glass spherical lenses and one glass aspherical lens, can achieve ultra-large field of view (maximum FOV value of 204°), large aperture (minimum FNO value of 1.6), miniaturization (minimum TTL value of 14.86mm) and high pixel count, thereby meeting the imaging requirements of automotive lenses.

[0126] 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.

[0127] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens comprising seven lenses, characterized in that, Along the optical axis from the object side to the imaging plane, the order is as follows: A first lens with negative optical power, wherein the object side of the first lens is convex and the image side is concave; A second lens with negative optical power, wherein the object side of the second lens is convex and the image side is concave; A third lens with positive optical power, wherein the object side of the third lens is convex and the image side is convex; A fourth lens with positive optical power, wherein the object side of the fourth lens is concave and the image side is convex; A fifth lens with positive optical power, wherein the object side of the fifth lens is convex and the image side is convex; A sixth lens with negative optical power, wherein the object side of the sixth lens is concave and the image side is concave; A seventh lens with positive optical power, wherein the object side of the seventh lens is concave and the image side is convex; Wherein, the radius of curvature R3 of the object side of the second lens and the radius of curvature R4 of the image side of the second lens satisfy: 0.50 < (R3-R4) / (R3+R4) < 0.95; The radius of curvature R7 of the object side of the fourth lens and the radius of curvature R8 of the image side of the fourth lens satisfy: 0.10 < (R7-R8) / (R7+R8) < 0.50; The radius of curvature R13 of the object side of the seventh lens and the radius of curvature R14 of the image side of the seventh lens satisfy: 0.60 < (R13-R14) / (R13+R14) < 0.

99.

2. The optical lens according to claim 1, characterized in that, The maximum field of view (FOV) of the optical lens and the aperture value (FNO) of the optical lens satisfy the following condition: 100° < FOV / FNO < 130°.

3. The optical lens according to claim 1, characterized in that, The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy the following condition: 10.0 < TTL / f < 15.

0.

4. The optical lens according to claim 1, characterized in that, The image height IH corresponding to the maximum field of view of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view of the optical lens satisfy: 0.95 < (IH / 2) / (f×θ) < 1.

10.

5. The optical lens according to claim 1, characterized in that, The optical back focal length (BFL) of the optical lens and the effective focal length (f) of the optical lens satisfy the condition: 1.8 < BFL / f < 2.

5.

6. The optical lens according to claim 1, characterized in that, The effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -5.92≤f1 / f<-5.

0.

7. The optical lens according to claim 1, characterized in that, The effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.5 < f2 / f < -2.

5.

8. The optical lens according to claim 1, characterized in that, The effective focal length f3 of the third lens and the effective focal length f of the optical lens satisfy the following condition: 5.0 < f3 / f ≤ 6.

32.

9. The optical lens according to claim 1, characterized in that, The effective focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy the following condition: 6.0 < f4 / f ≤ 7.

94.

10. The optical lens according to claim 1, characterized in that, The effective focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy the condition: 3.0 < f7 / f < 5.0.

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