An optical imaging system

Abstract

The present invention relates to an ultra-wide-angle optical imaging system, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens, arranged in sequence along an optical axis from an object side to an image side, wherein the first lens, the second lens, and the seventh lens have negative optical power, the fourth lens, the fifth lens, the sixth lens, the eighth lens, and the ninth lens have positive optical power, and the third lens has positive optical power or negative optical power; the first lens and the second lens are convex-concave lenses, the image-side surface of the third lens is a concave surface, the fourth lens is a concave-convex lens or the object-side surface is a convex surface, the fifth lens and the sixth lens are convex-convex lenses, the seventh lens is a concave-concave lens, the object-side surface of the eighth lens is a convex surface, and the image-side surface of the ninth lens is a convex surface.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and in particular to an ultra-wide-angle optical imaging system. Background Art

[0002] With the development of optical technology, wide-angle lenses are widely used in many fields such as security monitoring, drone photography, mobile phone photography, machine vision, and sports cameras due to their advantages such as wide shooting field of view and clear imaging. However, the development trend and difficulty of such lenses are often to achieve larger shooting angles, greater light intake, higher-definition images, and smaller size. The existing ultra-wide-angle lenses on the market have the following main defects:

[0003] 1. The head is often large and the lens is heavy, which cannot meet the requirements of miniaturization and lightweighting;

[0004] 2. The image quality of most ultra-wide-angle lenses is not high-definition enough;

[0005] 3. Although some ultra-wide-angle lenses can meet higher image quality requirements, their aperture is often very small and cannot adapt to dark environments at night or on rainy days.

[0006] Therefore, there is an urgent need for lenses that can achieve ultra-wide angles, large apertures, high resolutions, and small sizes. Summary of the Invention

[0007] In view of the above deficiencies in the prior art, an object of the present invention is to provide an ultra-wide-angle optical imaging system.

[0008] To achieve the above-mentioned object, the present invention provides an ultra-wide-angle optical imaging system, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens arranged in sequence along an optical axis from the object side to the image side, wherein the first lens, the second lens, and the seventh lens have negative optical power, and the fourth lens, the fifth lens, the sixth lens, the eighth lens, and the ninth lens have positive optical power, and the third lens has positive or negative optical power;

[0009] The first lens and the second lens are convex-concave lenses, the image-side surface of the third lens is concave, the fourth lens is a convex-concave lens or the object-side surface is convex, the fifth lens and the sixth lens are convex-convex lenses, the seventh lens is a convex-concave lens, the object-side surface of the eighth lens is convex, and the image-side surface of the ninth lens is convex.

[0010] According to one aspect of the present invention, the optical imaging system further includes a doublet lens formed by cementing the sixth lens and the seventh lens.

[0011] According to one aspect of the present invention, the combined focal length f67 of the sixth lens and the seventh lens and the total focal length f of the optical imaging system satisfy the condition: -6.6≤f67 / f≤-4.0.

[0012] According to one aspect of the present invention, the refractive index nd6 of the sixth lens and the refractive index nd7 of the seventh lens satisfy the condition: 30≤|nd6−nd7|≤60.

[0013] According to one aspect of the present invention, the Abbe number vd6 of the sixth lens and the Abbe number vd7 of the seventh lens satisfy the condition: 0.1≤|vd6-vd7|≤0.5.

[0014] According to one aspect of the present invention, the optical imaging system further includes: an aperture located between the fourth lens and the fifth lens.

[0015] According to one aspect of the present invention, the total optical length TTL of the optical imaging system, the center thickness CT4 of the fourth lens, and the distance T4 from the image side surface of the fourth lens to the aperture on the optical axis satisfy the condition: 6.1≤TTL / (T4+CT4)≤12.

[0016] According to one aspect of the present invention, the focal length f1 of the first lens and the total focal length f of the optical imaging system satisfy the condition: -2.5≤f1 / f≤-1.6.

[0017] According to one aspect of the present invention, the focal length f2 of the second lens and the total focal length f of the optical imaging system satisfy the condition: -5.8≤f2 / f≤-2.5.

[0018] According to one aspect of the present invention, the focal length f3 of the third lens, the focal length f4 of the fourth lens, and the total focal length f of the optical imaging system satisfy the condition: 1.8≤(f4-f3) / f≤10.

[0019] According to one aspect of the present invention, the focal length f5 of the fifth lens and the total focal length f of the optical imaging system satisfy the condition: 1.7≤f5 / f≤3.6.

[0020] According to one aspect of the present invention, the focal length f6 of the sixth lens and the total focal length f of the optical imaging system satisfy the condition: 1.5≤f6 / f≤2.4.

[0021] According to one aspect of the present invention, the focal length f7 of the seventh lens and the total focal length f of the optical imaging system satisfy the condition: -1.6≤f7 / f≤-0.7.

[0022] According to one aspect of the present invention, a center thickness CT6 of the sixth lens and a center thickness CT7 of the seventh lens satisfy the condition: 4.5≤CT6 / CT7≤7.0.

[0023] According to one aspect of the present invention, the focal length f8 of the eighth lens, the focal length f9 of the ninth lens, and the total focal length f of the optical imaging system satisfy the condition: 17.3≤(f8+f9) / f≤46.6.

[0024] According to one aspect of the present invention, the front group focal length fa of the first to fourth lenses and the total focal length f of the optical imaging system satisfy the condition: -3.8≤fa / f≤-1.2.

[0025] According to one aspect of the present invention, the rear focal lengths fb of the fifth to ninth lenses and the total focal length f of the optical imaging system satisfy the condition: 1.8≤fb / f≤2.8.

[0026] According to one aspect of the present invention, the front group focal length fa of the first to fourth lenses and the rear group focal length fb of the fifth to ninth lenses satisfy the condition: -1.6≤fa / fb≤-0.3.

[0027] According to one aspect of the present invention, a center distance D12 between the image side surface of the first lens and the object side surface of the second lens on the optical axis, a center distance D45 between the image side surface of the fourth lens and the object side surface of the fifth lens on the optical axis, and a total optical length TTL of the optical imaging system satisfy the condition: 0≤(D12+D45) / TTL≤0.2.

[0028] According to one aspect of the present invention, the diameter D1 of the first lens and the total optical length TTL of the optical imaging system satisfy the condition: 0.3≤D1 / TTL≤0.8.

[0029] According to one aspect of the present invention, the total optical length TTL of the optical imaging system and the total focal length f of the optical imaging system satisfy the condition: 7.9≤TTL / f≤8.6.

[0030] According to one aspect of the present invention, the back focus BFL of the optical imaging system and the total optical length TTL of the optical imaging system satisfy the condition: 0.1≤BFL / TTL≤0.2.

[0031] According to the solution of the present invention, by adopting an optical architecture of 9 lenses, through the combination of lenses of different shapes, materials, refractive powers and specific parameters and setting different distances and thicknesses, the ultra-wide-angle optical imaging system also has the characteristics of large aperture, high resolution, small size and light weight, and can also achieve the performance of no out-of-focus in high and low temperature processes.

[0032] The optical imaging system boasts a field of view of up to 160°, enabling its application in a variety of scenarios and enhancing its market competitiveness. The imaging target area can reach 1 / 1.8", and the optical imaging system boasts a resolution of up to 35 million pixels, meeting high-standard imaging requirements. A large aperture of FNO1.8 allows for greater light throughput, resulting in better night vision. The chief ray incident angle (CRA) is less than 18°, making it compatible with a variety of large-target sensors, demonstrating broad application prospects and high market competitiveness. By combining different lens materials, the optical imaging system can deliver high-definition image quality within a temperature range of -40° to 80°. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0034] Figure 1 Schematically illustrates the optical architecture of the ultra-wide-angle optical imaging system according to the first embodiment of the present invention;

[0035] Figure 2 Schematically illustrates the optical architecture of the ultra-wide-angle optical imaging system according to the second embodiment of the present invention;

[0036] Figure 3 Schematically illustrates the optical architecture of the ultra-wide-angle optical imaging system according to the third embodiment of the present invention;

[0037] Figure 4 The optical architecture of the ultra-wide-angle optical imaging system according to the fourth embodiment of the present invention is schematically shown. Specific embodiments

[0038] The description of the embodiments in this specification should be taken in conjunction with the corresponding drawings, which should be considered a complete part of this specification. In the drawings, the shapes and thicknesses of the embodiments may be exaggerated and indicated for simplicity or convenience. Furthermore, the various structural components in the drawings will be described separately. It is important to note that components not shown in the drawings or described in detail are known to those of ordinary skill in the art.

[0039] The description of the embodiments herein and any references to directions and orientations are for ease of description only and are not to be construed as limiting the scope of the present invention. The following description of the preferred embodiments may involve combinations of features, which may exist independently or in combination. The present invention is not specifically limited to the preferred embodiments. The scope of the present invention is defined by the claims.

[0040] In the embodiments of this specification, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, 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 image side is called the image-side surface of the lens.

[0041] like Figure 1 As shown, an embodiment of the present invention provides an ultra-wide-angle optical imaging system, comprising: a first lens L1, a second lens L2, 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 ninth lens L9, arranged in sequence along the optical axis from the object side to the image side. The first lens L1, the second lens L2, and the seventh lens L7 have negative optical power; the fourth lens L4, the fifth lens L5, the sixth lens L6, the eighth lens L8, and the ninth lens L9 have positive optical power; and the third lens L3 has positive or negative optical power.

[0042] Regarding lens shapes, the first and second lenses, L1 and L2, are both convex-concave lenses. The image-side surface of the third lens, L3, is concave. The object-side surface of the fourth lens, L4, is convex, or the fourth lens, L4, is a meniscus lens. The fifth and sixth lenses, L5 and L6, are both convex-convex lenses. The seventh lens, L7, is a meniscus lens. The object-side surface of the eighth lens, L8, is convex. The image-side surface of the ninth lens, L9, is convex. The ninth lens, L9, has an aspherical surface. All nine lenses are glass lenses.

[0043] The optical imaging system also includes a doublet lens formed by cementing a sixth lens L6 and a seventh lens L7.

[0044] According to the above scheme, the first lens L1 adopts a convex-concave shape, which helps to collect light rays at a wider angle into the system, thereby achieving a wide field of view. It also deflects light rays, reducing their angle of incidence upon entering the rear lens group (the lens on the image side of the first lens L1), thereby further minimizing the significant aberrations caused by light rays incident at high angles. The second lens L2 adopts a convex-concave shape, which can share the large negative power of the front lens (i.e., the first lens L1), reducing the sensitivity of the first lens L1, while further deflecting light rays at a wider angle, thereby facilitating the transmission of light by the rear lens group (the lens on the image side of the second lens L2). According to one embodiment of the present invention, the third lens L3 is a biconcave lens with negative power, which helps to balance the angle of incidence of light rays, increase the clear aperture, and achieve a wider aperture. According to another embodiment of the present invention, the third lens L3 can also be a convex-concave lens with positive power, which helps to compensate for aberrations such as field curvature and chromatic aberration generated by the first and second lenses L1 and L2, thereby reducing the pressure on aberration correction of the rear lens group (the lens on the image side of the third lens L3). According to one embodiment of the present invention, the object-side surface of the fourth lens element L4 is convex, which facilitates smooth light transitions within the system, thereby reducing tolerance sensitivity and improving resolution. According to another embodiment of the present invention, the fourth lens element L4 adopts a concave-convex shape, which facilitates correction of system field curvature to meet higher imaging requirements. The fifth lens element L5 has positive optical power, which facilitates correction of system chromatic aberration to meet higher imaging requirements. The sixth lens element L6 has a biconvex shape, which facilitates lowering of high-angle light near the aperture STO, allowing more light to enter the rear lens (located on the image side of the sixth lens element L6). The positive optical power of the sixth lens element L6 and the negative optical power of the seventh lens element L7 are cemented together to facilitate correction of chromatic aberration and achieve lower tolerance sensitivity. The eighth lens element L8 has positive optical power, which facilitates further correction of chromatic aberration to meet higher imaging requirements. The ninth lens element L9 adopts an aspheric surface shape, which facilitates reducing the chief ray angle to match the chip CRA curve. The image-side surface of the lens element is convex, which facilitates correction of peripheral field distortion, thereby better meeting imaging quality requirements.

[0045] Furthermore, the combined focal length f67 of the sixth lens element L6 and the seventh lens element L7, and the total focal length f of the optical imaging system, satisfy the condition: -6.6 ≤ f67 / f ≤ -4.0. The refractive index nd6 of the sixth lens element L6 and the refractive index nd7 of the seventh lens element L7 satisfy the condition: 30 ≤ |nd6 - nd7| ≤ 60. The Abbe number vd6 of the sixth lens element L6 and the Abbe number vd7 of the seventh lens element L7 satisfy the condition: 0.1 ≤ |vd6 - vd7| ≤ 0.5. The combination of two lenses, one with positive and one with negative refractive power, can offset each other's aberrations. By optimizing the refractive indices and chromatic aberrations of the two lenses L6 and L7 through the arrangement of the positive and negative lenses in the cemented lens, the setting of the combined focal length of the positive and negative lenses, and the glass materials, the chromatic aberrations of the two lenses can be effectively corrected, thereby improving the system's resolution and facilitating athermal design.

[0046] According to an embodiment of the present invention, the optical imaging system further includes: an aperture STO located between the fourth lens L4 and the fifth lens L5. Furthermore, the total optical length TTL of the optical imaging system, the center thickness CT4 of the fourth lens L4, and the distance T4 from the image side surface of the fourth lens L4 to the aperture STO on the optical axis satisfy the condition: 6.1≤TTL / (T4+CT4)≤12. The total optical length TTL of the optical imaging system in the embodiment of the present invention refers to the distance from the object side surface of the first lens L1 to the imaging surface IMA of the optical lens on the optical axis. By reasonably increasing the distance between the aperture STO and the fourth lens L4 and the center thickness of the fourth lens L4, light rays from different fields of view diverge at a reasonable angle after being converged by the aperture STO, thereby converging to a farther vertical axis position, thereby increasing the imaging height of the optical lens.

[0047] According to an embodiment of the present invention, the focal length f1 of first lens L1 and the total focal length f of the optical imaging system satisfy the condition: -2.5 ≤ f1 / f ≤ -1.6. This ensures machinability while enabling the optical imaging system to capture light at a wider angle within a given aperture, thus meeting ultra-wide-angle requirements.

[0048] According to an embodiment of the present invention, the focal length f2 of second lens element L2 and the total focal length f of the optical imaging system satisfy the condition: -5.8 ≤ f2 / f ≤ -2.5. This allows second lens element L2 to have an appropriately negative optical power, facilitating smoother light entry into the system, reducing the difficulty of aberration correction, and enhancing the resolving power of the optical lens.

[0049] According to an embodiment of the present invention, the focal length f3 of the third lens element L3, the focal length f4 of the fourth lens element L4, and the total focal length f of the optical imaging system satisfy the condition: 1.8 ≤ (f4 - f3) / f ≤ 10. This facilitates widening the light beam width, allowing wide-angle light rays captured by the third lens element L3 to be fully transmitted to the rear optical system, thereby achieving a wider field of view and higher relative illumination.

[0050] According to an embodiment of the present invention, the focal length f5 of the fifth lens element L5 and the total focal length f of the optical imaging system satisfy the condition: 1.7 ≤ f5 / f ≤ 3.6. Adjusting the focal length of the fifth lens element L5 within this range can mitigate shape changes in the fifth lens element L5. Since the fifth lens element L5 is positioned behind the aperture stop STO (on the image side of the aperture stop STO), it can better correct aberrations introduced by the preceding lens groups (i.e., the first to fourth lenses), improve high-order spherical aberration and coma, and facilitate high resolution and uniform overall resolution.

[0051] According to an embodiment of the present invention, the focal length f6 of sixth lens element L6 and the total focal length f of the optical imaging system satisfy the condition: 1.5 ≤ f6 / f ≤ 2.4. By providing sixth lens element L6 with an appropriately positive refractive power, light convergence is facilitated, allowing divergent light entering the system from the front to smoothly enter the rear optical system, resulting in a smoother overall optical path, optimized aberrations, and improved resolution.

[0052] According to an embodiment of the present invention, the focal length f7 of the seventh lens element L7 and the total focal length f of the optical imaging system satisfy the condition: -1.6 ≤ f7 / f ≤ -0.7. This configuration facilitates the rational distribution of the overall refractive power of the optical lens, improves the imaging resolution of the optical lens, and achieves high-pixel imaging.

[0053] According to embodiments of the present invention, the center thickness CT6 of the sixth lens element L6 and the center thickness CT7 of the seventh lens element L7 satisfy the condition: 4.5 ≤ CT6 / CT7 ≤ 7.0. By controlling the center thicknesses of the sixth lens element L6 and the seventh lens element L7, the thickness sensitivity of the fixed-focus lens can be reduced, effectively correcting the field curvature and distortion of the optical system, thereby achieving excellent image quality across the entire field of view.

[0054] According to embodiments of the present invention, the focal length f8 of the eighth lens element L8, the focal length f9 of the ninth lens element L9, and the total focal length f of the optical imaging system satisfy the equation: 17.3 ≤ (f8 + f9) / f ≤ 46.6. By properly configuring the focal powers of the eighth and ninth lenses, light can be appropriately diverged, thereby increasing the imaging area of the lens, optimizing image quality, and enhancing the overall resolution of the lens.

[0055] According to an embodiment of the present invention, the front focal length fa of the first through fourth lens elements L1 through L4 and the total focal length f of the optical imaging system satisfy the following equation: -3.8 ≤ fa / f ≤ -1.2. The rear focal length fb of the fifth through ninth lens elements L5 through L9 and the total focal length f of the optical imaging system satisfy the following equation: 1.8 ≤ fb / f ≤ 2.8. The front focal length fa of the first through fourth lens elements L1 through L4 and the rear focal length fb of the fifth through ninth lens elements L5 through L9 satisfy the following equation: -1.6 ≤ fa / fb ≤ -0.3. The front focal length fa is the combined focal length of the first, second, third, and fourth lens elements, while the rear focal length fb is the combined focal length of the fifth, sixth, seventh, eighth, and ninth lens elements. By properly controlling the focal length ratios between lens groups, the forward light rays are smoothly converged near the optical axis, effectively correcting wide-angle distortion. It also effectively reduces off-axis wide beam aberrations and field curvature, significantly improving edge image quality. It is also beneficial to correct the field curvature produced by the lens group located in front of the aperture STO (i.e., on the object side of the aperture STO), thereby reducing the influence of the field curvature on the resolving power.

[0056] According to an embodiment of the present invention, the center distance D12 on the optical axis between the image-side surface of the first lens element L1 and the object-side surface of the second lens element L2, the center distance D45 on the optical axis between the image-side surface of the fourth lens element L4 and the object-side surface of the fifth lens element L5, and the total optical length TTL of the optical imaging system satisfy the following equation: 0 ≤ (D12 + D45) / TTL ≤ 0.2. By adjusting the positions of the first, second, fourth, and fifth lenses in the optical imaging system and the distances between these lenses, it is possible to ensure high image quality while avoiding excessive overall size of the optical imaging lens, thereby facilitating both compactness and high image quality.

[0057] According to an embodiment of the present invention, the diameter D1 of the first lens L1 and the total optical length TTL of the optical imaging system satisfy the condition: 0.3≤D1 / TTL≤0.8. By controlling the lens head diameter and the total optical length, the system can achieve a small size.

[0058] According to an embodiment of the present invention, the total optical length TTL of the optical imaging system and the total focal length f of the optical imaging system satisfy the conditional formula: 7.9 ≤ TTL / f ≤ 8.6. This helps shorten the total length TTL of the lens (i.e., the total optical length of the optical imaging system), avoids problems such as poor overall lens performance caused by an excessively small TTL / f ratio, and improves lens compatibility.

[0059] According to an embodiment of the present invention, the back focus (BFL) of the optical imaging system and the total optical length (TTL) of the optical imaging system satisfy the condition: 0.1 ≤ BFL / TTL ≤ 0.2. By controlling the ratio of back focus to total optical length, interference between the lens and the chip caused by insufficient back focus can be avoided, thereby affecting the overall imaging quality of the lens.

[0060] In summary, according to the above solution, the embodiments of the present invention utilize the aforementioned nine-lens optical architecture, combining lenses of varying shapes, materials, refractive powers, and specific parameters, and setting them at varying distances and thicknesses. This enables an ultra-wide-angle optical imaging system that combines the advantages of a large aperture, high resolution, a compact size, and light weight, while also achieving blur-free performance in both high and low temperature environments. Specifically, the optical lens achieves a field of view of up to 160°, enabling applications in a wide range of scenarios and enhancing market competitiveness. The imaging target area can reach 1 / 1.8", and the optical system's resolution reaches up to 35 megapixels, meeting high-standard imaging requirements. A large aperture of FNO 1.8 enables greater light throughput, resulting in improved night vision. A chief ray incidence angle (CRA) of less than 18° compatibility with a variety of large-area sensors offers broad application prospects and high market competitiveness. By combining different lens materials, the optical imaging system can deliver high-definition image quality across a temperature range of -40° to 80°.

[0061] The following four embodiments, combined with accompanying figures and tables, specifically illustrate the ultra-wide-angle optical imaging system of the present invention. In each of the following embodiments, the present invention designates the aperture STO as one surface, the parallel plates CG as two surfaces, the image plane IMA as one surface, and the cemented surface of the doublet lens as one surface.

[0062] Parameters of various embodiments that specifically meet the above conditional formula are shown in Table 1 below:

[0063]

[0064]

[0065] Table 1

[0066] In an embodiment of the present invention, the aspheric lens of the ultra-wide-angle optical imaging system satisfies the following formula:

[0067]

[0068] In the above formula, z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the cone coefficient; A4, A6, A8, A 10 、A 12 、A 14、A 16 ···represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order···aspheric coefficients respectively.

[0069] Example 1

[0070] See also Figure 1 In this embodiment, the first lens element L1 has negative focal power, the second lens element L2 has negative focal power, the third lens element L3 has negative focal power, the fourth lens element L4 has positive focal power, the fifth lens element L5 has positive focal power, the sixth lens element L6 has positive focal power, the seventh lens element L7 has negative focal power, the eighth lens element L8 has positive focal power, and the ninth lens element L9 has positive focal power. A stop STO is located between the fourth lens element L4 and the fifth lens element L5.

[0071] Along the optical axis from the object side to the image side, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-concave lens, the third lens L3 is a convex-concave lens, the fourth lens L4 is a convex-convex lens, the fifth lens L5 is a convex-convex lens, the sixth lens L6 is a convex-convex lens, the seventh lens L7 is a convex-concave lens, the eighth lens L8 is a convex-concave lens, and the ninth lens L9 is a convex-convex lens.

[0072] The second lens L2, the fourth lens L4, the fifth lens L5 and the ninth lens L9 are all aspherical lenses.

[0073] This embodiment includes a doublet lens consisting of a sixth lens L6 and a seventh lens L7 cemented together.

[0074] The relevant parameters of each lens in the ultra-wide-angle optical imaging system of this embodiment include: surface number (Surf), surface type (Type), curvature radius (Radius), thickness (Thickness), material refractive index (Nd) and Abbe number (Vd), as shown in Table 2 below.

[0075]

[0076] Table 2

[0077] The aspheric coefficients of each aspheric lens of the ultra-wide-angle optical imaging system of this embodiment include: the quadratic surface constant K, the fourth-order aspheric coefficient A4, the sixth-order aspheric coefficient A6, the eighth-order aspheric coefficient A8, the tenth-order aspheric coefficient A 10 and the twelfth-order aspheric coefficient A 12 , as shown in Table 3 below.

[0078] Surf K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 ]]> <![CDATA[A 12 ]]> 3 0.00 9.71E-03 -7.63E-04 7.73E-05 -4.80E-06 1.51E-07 4 0.00 1.20E-02 -7.71E-04 1.06E-04 -9.64E-06 4.67E-07 7 0.16 1.62E-04 -7.32E-06 -3.52E-05 5.30E-06 -4.66E-07 8 0.00 1.27E-03 2.57E-04 -3.84E-05 3.89E-06 -3.49E-07 10 0.62 -2.12E-03 2.91E-04 -3.79E-05 3.37E-06 -8.37E-08 11 -0.34 8.96E-04 3.32E-05 4.01E-06 1.07E-07 8.75E-08 17 0.00 9.94E-04 3.35E-05 -1.49E-06 -1.77E-08 2.50E-09 18 0.00 3.35E-03 -1.15E-05 4.98E-06 -4.82E-07 1.28E-08

[0079] Table 3

[0080] Combine Figure 1As shown in Tables 1 to 3 above, the ultra-wide-angle optical imaging system in this embodiment can achieve a field of view of 160°, an imaging target area of 1 / 1.8", a resolution of up to 35 million pixels, and a chief ray incidence angle (CRA) of less than 18°, achieving a large aperture of FNO1.8. This allows the optical imaging system to have greater light throughput, thereby achieving better night vision. It can also achieve high-definition image quality within a temperature range of -40 to 80°.

[0081] Example 2

[0082] See also Figure 2 In this embodiment, the first lens element L1 has negative optical power, the second lens element L2 has negative optical power, the third lens element L3 has positive optical power, the fourth lens element L4 has positive optical power, the fifth lens element L5 has positive optical power, the sixth lens element L6 has positive optical power, the seventh lens element L7 has negative optical power, the eighth lens element L8 has positive optical power, and the ninth lens element L9 has positive optical power. A stop STO is located between the fourth lens element L4 and the fifth lens element L5.

[0083] Along the optical axis from the object side to the image side, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-concave lens, the third lens L3 is a convex-concave lens, the fourth lens L4 is a convex-convex lens, the fifth lens L5 is a convex-convex lens, the sixth lens L6 is a convex-convex lens, the seventh lens L7 is a convex-concave lens, the eighth lens L8 is a convex-convex lens, and the ninth lens L9 is a convex-convex lens.

[0084] The second lens L2, the third lens L3, the fifth lens L5 and the ninth lens L9 are all aspherical lenses.

[0085] This embodiment includes a doublet lens consisting of a sixth lens L6 and a seventh lens L7 cemented together.

[0086] The relevant parameters of each lens in the ultra-wide-angle optical imaging system of this embodiment include: surface number (Surf), surface type (Type), curvature radius (Radius), thickness (Thickness), material refractive index (Nd) and Abbe number (Vd), as shown in Table 4 below.

[0087]

[0088]

[0089] Table 4

[0090] The aspheric coefficients of each aspheric lens of the ultra-wide-angle optical imaging system of this embodiment include: the quadratic surface constant K, the fourth-order aspheric coefficient A4, the sixth-order aspheric coefficient A6, the eighth-order aspheric coefficient A8, the tenth-order aspheric coefficient A 10 , 12th-order aspheric coefficient A12 and the fourteenth-order aspheric coefficient A 14 , as shown in Table 5 below.

[0091] Surf K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 ]]> <![CDATA[A 12 ]]> <![CDATA[A 14 ]]> 3 -2.10 7.53E-03 -9.26E-04 5.32E-05 -1.35E-06 5.45E-08 0.00E+00 4 -0.17 5.25E-03 -1.12E-03 -8.66E-05 1.00E-05 -5.83E-07 0.00E+00 5 9.79 6.58E-03 2.49E-04 -4.25E-05 -8.12E-07 -7.88E-07 0.00E+00 6 90.00 1.07E-02 6.88E-04 1.12E-05 7.88E-06 -6.57E-06 0.00E+00 10 59.54 2.96E-03 9.35E-05 1.31E-05 -1.80E-06 2.10E-07 2.82E-09 11 0.38 1.80E-03 -2.57E-05 4.01E-05 -1.84E-06 -2.28E-07 4.89E-08 17 3.47 -3.41E-03 2.53E-06 -2.17E-05 3.26E-06 -7.04E-08 0.00E+00 18 -12.49 -4.10E-03 1.53E-04 -1.58E-05 1.56E-06 -3.82E-08 0.00E+00

[0092] Table 5

[0093] Combine Figure 2 As shown in Tables 1, 4, and 5 above, the ultra-wide-angle optical imaging system in this embodiment can achieve a field of view of 160°, an imaging target area of 1 / 1.8", a resolution of up to 35 million pixels, and a chief ray incident angle (CRA) of less than 18°, achieving a large aperture of FNO1.8. This allows the optical imaging system to have greater light throughput, thereby achieving better night vision. It can also achieve high-definition image quality within a temperature range of -40° to 80°.

[0094] Example 3

[0095] See also Figure 3 In this embodiment, the first lens element L1 has negative focal power, the second lens element L2 has negative focal power, the third lens element L3 has negative focal power, the fourth lens element L4 has positive focal power, the fifth lens element L5 has positive focal power, the sixth lens element L6 has positive focal power, the seventh lens element L7 has negative focal power, the eighth lens element L8 has positive focal power, and the ninth lens element L9 has positive focal power. A stop STO is located between the fourth lens element L4 and the fifth lens element L5.

[0096] Along the optical axis from the object side to the image side, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-concave lens, the third lens L3 is a convex-concave lens, the fourth lens L4 is a convex-convex lens, the fifth lens L5 is a convex-convex lens, the sixth lens L6 is a convex-convex lens, the seventh lens L7 is a convex-concave lens, the eighth lens L8 is a convex-convex lens, and the ninth lens L9 is a convex-convex lens.

[0097] The second lens L2, the fourth lens L4, the fifth lens L5 and the ninth lens L9 are all aspherical lenses.

[0098] This embodiment includes a doublet lens consisting of a sixth lens L6 and a seventh lens L7 cemented together.

[0099] The relevant parameters of each lens in the ultra-wide-angle optical imaging system of this embodiment include: surface number (Surf), surface type (Type), curvature radius (Radius), thickness (Thickness), material refractive index (Nd) and Abbe number (Vd), as shown in Table 6 below.

[0100]

[0101]

[0102] Table 6

[0103] The aspheric coefficients of each aspheric lens of the ultra-wide-angle optical imaging system of this embodiment include: the quadratic surface constant K, the fourth-order aspheric coefficient A4, the sixth-order aspheric coefficient A6, the eighth-order aspheric coefficient A8, the tenth-order aspheric coefficient A 10 and the twelfth-order aspheric coefficient A 12 , as shown in Table 7 below.

[0104]

[0105]

[0106] Table 7

[0107] Combine Figure 3 As shown in Tables 1, 6, and 7 above, the ultra-wide-angle optical imaging system in this embodiment can achieve a field of view of 160°, an imaging target area of 1 / 1.8", a resolution of up to 35 million pixels, and a chief ray incidence angle (CRA) of less than 18°, achieving a large aperture of FNO1.8. This allows the optical imaging system to have greater light throughput, thereby achieving better night vision. It can also achieve high-definition image quality within a temperature range of -40° to 80°.

[0108] Example 4

[0109] See also Figure 4 In this embodiment, the first lens element L1 has negative focal power, the second lens element L2 has negative focal power, the third lens element L3 has negative focal power, the fourth lens element L4 has positive focal power, the fifth lens element L5 has positive focal power, the sixth lens element L6 has positive focal power, the seventh lens element L7 has negative focal power, the eighth lens element L8 has positive focal power, and the ninth lens element L9 has positive focal power. A stop STO is located between the fourth lens element L4 and the fifth lens element L5.

[0110] Along the direction from the object side to the image side of the optical axis, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-concave lens, the third lens L3 is a convex-concave lens, the fourth lens L4 is a convex-concave lens, the fifth lens L5 is a convex-convex lens, the sixth lens L6 is a convex-convex lens, the seventh lens L7 is a convex-concave lens, the eighth lens L8 is a convex-convex lens, and the ninth lens L9 is a convex-convex lens.

[0111] The second lens L2, the fourth lens L4, the fifth lens L5 and the ninth lens L9 are all aspherical lenses.

[0112] This embodiment includes a doublet lens consisting of a sixth lens L6 and a seventh lens L7 cemented together.

[0113] The relevant parameters of each lens in the ultra-wide-angle optical imaging system of this embodiment include: surface number (Surf), surface type (Type), curvature radius (Radius), thickness (Thickness), material refractive index (Nd) and Abbe number (Vd), as shown in Table 8 below.

[0114]

[0115] Table 8

[0116] The aspheric coefficients of each aspheric lens of the ultra-wide-angle optical imaging system of this embodiment include: the quadratic surface constant K, the fourth-order aspheric coefficient A4, the sixth-order aspheric coefficient A6, the eighth-order aspheric coefficient A8, the tenth-order aspheric coefficient A 10 and the twelfth-order aspheric coefficient A 12 , as shown in Table 9 below.

[0117] Surf K <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 ]]> <![CDATA[A 12 ]]> 3 -12.84 1.00E-02 -8.96E-04 9.01E-05 -5.36E-06 1.52E-07 4 -28.46 1.87E-02 -2.31E-03 2.98E-04 -2.33E-05 8.10E-07 7 0.34 -8.40E-04 4.58E-06 -9.18E-06 7.81E-07 -6.15E-08 8 0.00 1.15E-03 8.21E-05 -1.75E-06 -1.19E-06 -2.06E-08 10 -1.02 2.78E-04 2.06E-04 -1.70E-05 1.21E-06 -2.00E-08 11 0.10 6.77E-04 4.58E-05 2.75E-06 1.10E-06 -8.21E-09 17 59.85 -5.48E-03 -4.68E-04 4.72E-05 -6.78E-06 3.70E-07 18 43.71 -4.12E-03 -3.09E-04 3.15E-05 -2.21E-06 7.89E-08

[0118] Table 9

[0119] Combine Figure 4 As shown in Tables 1, 8, and 9 above, the ultra-wide-angle optical imaging system in this embodiment can achieve a field of view of 160°, an imaging target area of 1 / 1.8", a resolution of up to 35 million pixels, and a chief ray incidence angle (CRA) of less than 18°, achieving a large aperture of FNO1.8. This allows the optical imaging system to have greater light throughput, thereby achieving better night vision. It can also achieve high-definition image quality within a temperature range of -40° to 80°.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An optical imaging system, comprising: A first lens (L1), a second lens (L2), 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 ninth lens (L9) are arranged in sequence along the optical axis from the object side to the image side, wherein the first lens (L1), the second lens (L2) and the seventh lens (L7) have negative optical power, and the fourth lens (L4), the fifth lens (L5), the sixth lens (L6), the eighth lens (L8) and the ninth lens (L9) have positive optical power. There are nine lenses with optical power in total, and the third lens (L3) has positive optical power or negative optical power; The first lens (L1) and the second lens (L2) are convex-concave lenses, the image side surface of the third lens (L3) is a concave surface, the fourth lens (L4) is a convex-concave lens or the object side surface is a convex surface, the fifth lens (L5) and the sixth lens (L6) are convex-convex lenses, the seventh lens (L7) is a concave-concave lens, the object side surface of the eighth lens (L8) is a convex surface, and the image side surface of the ninth lens (L9) is a convex surface.

2. The optical imaging system according to claim 1, wherein: The sixth lens (L6) and the seventh lens (L7) are cemented together to form a doublet lens.

3. The optical imaging system according to claim 1 or 2, characterized in that: The combined focal length f67 of the sixth lens (L6) and the seventh lens (L7) and the total focal length f of the optical imaging system satisfy the condition: -6.6≤f67 / f≤-4.

0.

4. The optical imaging system according to claim 1 or 2, characterized in that: The refractive index nd6 of the sixth lens (L6) and the refractive index nd7 of the seventh lens (L7) satisfy the condition: 30≤|nd6−nd7|≤60.

5. The ultra-wide-angle optical imaging system according to claim 1 or 2, characterized in that: The Abbe number vd6 of the sixth lens (L6) and the Abbe number vd7 of the seventh lens (L7) satisfy the condition: 0.1≤|vd6-vd7|≤0.

5.

6. The optical imaging system according to claim 1 or 2, characterized in that: The total optical length TTL of the optical imaging system, the center thickness CT4 of the fourth lens (L4), and the distance T4 from the image side surface of the fourth lens (L4) to the aperture stop (STO) on the optical axis satisfy the condition: 6.1≤TTL / (T4+CT4)≤12.

7. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f2 of the second lens (L2) and the total focal length f of the optical imaging system satisfy the condition: -5.8≤f2 / f≤-2.

5.

8. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f3 of the third lens (L3), the focal length f4 of the fourth lens (L4), and the total focal length f of the optical imaging system satisfy the condition: 1.8≤(f4-f3) / f≤10.

9. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f5 of the fifth lens (L5) and the total focal length f of the optical imaging system satisfy the condition: 1.7≤f5 / f≤3.

6.

10. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f6 of the sixth lens (L6) and the total focal length f of the optical imaging system satisfy the condition: 1.5≤f6 / f≤2.

4.

11. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f7 of the seventh lens (L7) and the total focal length f of the optical imaging system satisfy the condition: -1.6≤f7 / f≤-0.

7.

12. The optical imaging system according to claim 1 or 2, characterized in that: The center thickness CT6 of the sixth lens (L6) and the center thickness CT7 of the seventh lens (L7) satisfy the conditional formula: 4.5≤CT6 / CT7≤7.

0.

13. The optical imaging system according to claim 1 or 2, characterized in that: The focal length f8 of the eighth lens (L8), the focal length f9 of the ninth lens (L9), and the total focal length f of the optical imaging system satisfy the condition: 17.3≤(f8+f9) / f≤46.

6.

14. The optical imaging system according to claim 1 or 2, characterized in that: The combined focal length fa of the first lens (L1) to the fourth lens (L4) and the total focal length f of the optical imaging system satisfy the condition: -3.8≤fa / f≤-1.

2.

15. The optical imaging system according to claim 1 or 2, characterized in that: The combined focal length fb of the fifth lens (L5) to the ninth lens (L9) and the total focal length f of the optical imaging system satisfy the condition: 1.8≤fb / f≤2.

8.

16. The optical imaging system according to claim 1 or 2, characterized in that: The combined focal length fa of the first lens (L1) to the fourth lens (L4) and the combined focal length fb of the fifth lens (L5) to the ninth lens (L9) satisfy the condition: -1.6≤fa / fb≤-0.

3.

17. The optical imaging system according to claim 1 or 2, characterized in that: The center distance D12 between the image side surface of the first lens (L1) and the object side surface of the second lens (L2) on the optical axis, the center distance D45 between the image side surface of the fourth lens (L4) and the object side surface of the fifth lens (L5) on the optical axis, and the total optical length TTL of the optical imaging system satisfy the conditional formula: 0≤(D12+D45) / TTL≤0.

2.

18. The optical imaging system according to claim 1 or 2, characterized in that: The diameter D1 of the first lens (L1) and the total optical length TTL of the optical imaging system satisfy the conditional formula: 0.3≤D1 / TTL≤0.

8.

19. The optical imaging system according to claim 1 or 2, characterized in that: The total optical length TTL of the optical imaging system and the total focal length f of the optical imaging system satisfy the conditional formula: 7.9≤TTL / f≤8.

6.

20. The optical imaging system according to claim 1 or 2, characterized in that: The back focus BFL of the optical imaging system and the total optical length TTL of the optical imaging system satisfy the conditional formula: 0.1≤BFL / TTL≤0.2.

Images