Image capturing optical system, image capturing unit and electronic device

Abstract

An imaging optical system includes seven lenses. The seven lenses, arranged sequentially from the object side to the image side along the optical path, are a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Each of the seven lenses has an object-side surface facing the object side and an image-side surface facing the image side. The third lens has negative refractive power. The object-side surface of the fifth lens is concave near the optical axis. The sixth lens has positive refractive power. The seventh lens has negative refractive power. The object-side surface of the seventh lens is convex near the optical axis. The image-side surface of the seventh lens is concave near the optical axis and has at least one inflection point. Under certain conditions, the imaging optical system can simultaneously meet the requirements of miniaturization and high imaging quality.

Description

Technical Field

[0001] This disclosure relates to an imaging optical system, an imaging device, and an electronic device, particularly an imaging optical system and imaging device suitable for electronic devices. Prior Technology

[0002] With advancements in semiconductor manufacturing technology, the performance of electronic image sensors has improved, allowing pixels to reach smaller sizes. As a result, optical lenses with high image quality have become an indispensable component.

[0003] With the rapid advancement of technology, electronic devices equipped with optical lenses are being used in a wider range of applications, leading to more diverse requirements for these lenses. Since traditional optical lenses have struggled to achieve a balance between image quality, sensitivity, aperture size, size, and viewing angle, this invention provides an optical lens with high image quality to meet these demands. Summary of the Invention

[0004] This disclosure provides an imaging optical system, an imaging device, and an electronic device. The imaging optical system comprises seven lenses arranged sequentially along the optical path from the object side to the image side. Under certain conditions, the imaging optical system provided by this disclosure can simultaneously meet the requirements of miniaturization and high imaging quality.

[0005] This disclosure provides an imaging optical system comprising seven lenses. The seven lenses, arranged sequentially from the object side to the image side along the optical path, are a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Each of the seven lenses has an object-side surface facing the object side and an image-side surface facing the image side. Preferably, the third lens has negative refractive power. Preferably, the object-side surface of the fifth lens is concave near the optical axis. Preferably, the sixth lens has positive refractive power. Preferably, the seventh lens has negative refractive power. Preferably, the object-side surface of the seventh lens is convex near the optical axis. Preferably, the image-side surface of the seventh lens is concave near the optical axis. Preferably, the image-side surface of the seventh lens has at least one inflection point. The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL; the radius of curvature of the object-side surface of the first lens is R1; the radius of curvature of the object-side surface of the second lens is R3; the distance between the first and second lenses along the optical axis is T12; the distance between the second and third lenses along the optical axis is T23; the distance between the third and fourth lenses along the optical axis is T34; the distance between the fourth and fifth lenses along the optical axis is T45; the distance between the fifth and sixth lenses along the optical axis is T56; and the distance between the sixth and seventh lenses along the optical axis is T67. Preferably, the following conditions are satisfied:

[0006] -2.50 < TL / R1 < 1.00;

[0007] -2.50 < TL / R3 < 1.70; and

[0008] 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.70.

[0009] This disclosure also provides an imaging optical system comprising seven lenses. The seven lenses, arranged sequentially from the object side to the image side along the optical path, are a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Each of the seven lenses has an object-side surface facing the object side and an image-side surface facing the image side. Preferably, the image-side surface of the second lens is convex near the optical axis. Preferably, the third lens has negative refractive power. Preferably, the fifth lens has negative refractive power. Preferably, the object-side surface of the fifth lens is concave near the optical axis. Preferably, the image-side surface of the fifth lens is convex near the optical axis. Preferably, the seventh lens has negative refractive power. Preferably, the image-side surface of the seventh lens has at least one inflection point. The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL; the radius of curvature of the object-side surface of the first lens is R1; the radius of curvature of the object-side surface of the second lens is R3; the focal length of the sixth lens is f6; the focal length of the seventh lens is f7; the distance between the fourth and fifth lenses along the optical axis is T45; and the distance between the sixth and seventh lenses along the optical axis is T67. Preferably, the following conditions are satisfied:

[0010] -2.20 < TL / R1 < 1.00;

[0011] -2.50 < TL / R3 < 2.00;

[0012] 0.00 < |f6 / f7| < 1.00; and

[0013] 0.00 < T67 / T45 < 0.80.

[0014] This disclosure also provides an imaging optical system comprising seven lenses. The seven lenses, arranged sequentially from the object side to the image side along the optical path, are a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Each of the seven lenses has an object-side surface facing the object side and an image-side surface facing the image side. Preferably, the object-side surface of the first lens is concave near the optical axis. Preferably, the object-side surface of the second lens is concave near the optical axis. Preferably, the third lens has negative refractive power. Preferably, the object-side surface of the fifth lens is concave near the optical axis. Preferably, the image-side surface of the fifth lens is convex near the optical axis. Preferably, the sixth lens has positive refractive power. Preferably, the image-side surface of the seventh lens has at least one inflection point. The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL, the radius of curvature of the object-side surface of the first lens is R1, and the radius of curvature of the object-side surface of the second lens is R3, preferably satisfying the following conditions:

[0015] TL / R1 < 0.00; and

[0016] TL / R3 < 0.00.

[0017] This disclosure provides an imaging device, which includes the aforementioned imaging optical system and an electronic photosensitive element, wherein the electronic photosensitive element is disposed on the imaging surface of the imaging optical system.

[0018] This disclosure provides an electronic device that includes the aforementioned image capturing device.

[0019] When TL / R1 meets the above conditions, the ratio of the total length of the imaging optical system to the radius of curvature of the object-side surface of the first lens can be adjusted, which helps to adjust the viewing angle.

[0020] When TL / R3 meets the above conditions, the ratio of the total length of the imaging optical system to the radius of curvature of the object-side surface of the second lens can be adjusted, which helps to adjust the surface shape and refractive power of the second lens to improve the central imaging quality.

[0021] When (T12+T23+T56+T67) / (T34+T45) satisfies the above conditions, it helps to balance the lens distribution.

[0022] When |f6 / f7| meets the above conditions, it helps to balance the refractive force configuration at the image side.

[0023] When T67 / T45 meets the above conditions, it helps to compress the volume of the imaging optical system at the image side. Simple Explanation of the Diagram

[0024] Figure 1 illustrates a schematic diagram of an imaging device according to a first embodiment of the present disclosure. Figure 2 shows the spherical aberration, astigmatism, and distortion curves of the first embodiment from left to right. Figure 3 illustrates a schematic diagram of an imaging device according to a second embodiment of this disclosure. Figure 4 shows the spherical aberration, astigmatism, and distortion curves of the second embodiment from left to right. Figure 5 illustrates a schematic diagram of an imaging device according to a third embodiment of this disclosure. Figure 6 shows the spherical aberration, astigmatism, and distortion curves of the third embodiment from left to right. Figure 7 illustrates a schematic diagram of an imaging device according to the fourth embodiment of this disclosure. Figure 8 shows the spherical aberration, astigmatism, and distortion curves of the fourth embodiment from left to right. Figure 9 illustrates a schematic diagram of an imaging device according to the fifth embodiment of this disclosure. Figure 10 shows the spherical aberration, astigmatism, and distortion curves of the fifth embodiment from left to right. Figure 11 illustrates a schematic diagram of an imaging device according to the sixth embodiment of this disclosure. Figure 12 shows the spherical aberration, astigmatism, and distortion curves of the sixth embodiment from left to right. Figure 13 illustrates a schematic diagram of an imaging device according to the seventh embodiment of this disclosure. Figure 14 shows the spherical aberration, astigmatism, and distortion curves of the seventh embodiment from left to right. Figure 15 illustrates a schematic diagram of an imaging device according to the eighth embodiment of this disclosure. Figure 16 shows the spherical aberration, astigmatism, and distortion curves of the eighth embodiment from left to right. Figure 17 illustrates a schematic diagram of an imaging device according to the ninth embodiment of this disclosure. Figure 18 shows the spherical aberration, astigmatism, and distortion curves of the ninth embodiment from left to right. Figure 19 illustrates a schematic diagram of an imaging device according to the tenth embodiment of this disclosure. Figure 20 shows the spherical aberration, astigmatism, and distortion curves of the tenth embodiment from left to right. Figure 21 illustrates a schematic diagram of an imaging device according to the eleventh embodiment of this disclosure. Figure 22 shows the spherical aberration, astigmatism, and distortion curves of the eleventh embodiment from left to right. Figure 23 illustrates a schematic diagram of an imaging device according to the twelfth embodiment of this disclosure. Figure 24 shows the spherical aberration, astigmatism, and distortion curves of the twelfth embodiment from left to right. Figure 25 illustrates a perspective view of an imaging device according to the thirteenth embodiment of this disclosure. Figure 26 illustrates a perspective view of one side of an electronic device according to the fourteenth embodiment of this disclosure. Figure 27 shows a three-dimensional schematic diagram of the other side of the electronic device in Figure 26. Figure 28 illustrates a perspective view of one side of an electronic device according to the fifteenth embodiment of this disclosure. Figure 29 shows a three-dimensional schematic diagram of the other side of the electronic device in Figure 28. Figure 30 shows a system block diagram of the electronic device in Figure 28. Figure 31 illustrates a perspective view of one side of an electronic device according to the sixteenth embodiment of this disclosure. Figure 32 illustrates a perspective view of one side of an electronic device according to the seventeenth embodiment of this disclosure. Figure 33 illustrates a perspective view of one side of an electronic device according to the eighteenth embodiment of this disclosure. Figure 34 illustrates a schematic diagram of the inflection point and the critical point on the lens surface according to the first embodiment of this disclosure. Figure 35 illustrates a schematic diagram of parameters Y2R1 and Y7R2 according to the first embodiment of this disclosure. Figure 36 illustrates a schematic diagram of the configuration of an optical path reversing element in an imaging optical system according to the present disclosure. Figure 37 illustrates another configuration of an optical path reversing element in an imaging optical system according to the present disclosure. Figure 38 illustrates a schematic diagram of the configuration of two optical path deflection elements in an imaging optical system in accordance with the present disclosure. Implementation

[0025] The imaging optical system comprises seven lenses, which are arranged sequentially from the object side to the image side along the optical path as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. Each of the seven lenses has an object-side surface facing the object side and an image-side surface facing the image side.

[0026] The object-side surface of the first lens can be concave near the optical axis. This helps to adjust the refractive power and viewing angle of the first lens. The image-side surface of the first lens can be convex near the optical axis. This helps to increase the viewing angle of the imaging optical system and adjust the refractive power of the first lens.

[0027] The object-side surface of the second lens can be concave near the optical axis. This allows it to match the surface shape of the first lens, helping to improve light-gathering quality. The image-side surface of the second lens can be convex near the optical axis. This allows control over the light path and helps avoid total internal reflection caused by excessive deflection angles.

[0028] The third lens can have negative refractive power. This helps to balance the aberrations produced by the first and second lenses. The image-side surface of the third lens can be concave near the optical axis. This allows for adjustment of the optical path and helps to increase the imaging area.

[0029] The fourth lens can have positive refractive power. This helps to reduce volume and improve the light-gathering ability of the imaging optics system. The image-side surface of the fourth lens can be convex near the optical axis. This helps to control the size of the peripheral field beam and reduce peripheral vignetting distortion of the image.

[0030] The fifth lens can have negative refractive power. This helps reduce spherical aberration in the imaging optics. The object-side surface of the fifth lens can be concave near the optical axis. This helps enhance the negative refractive power of the fifth lens and improve chromatic aberration in the imaging optics. The image-side surface of the fifth lens can be convex near the optical axis. This helps correct aberrations in the imaging optics and maintain good image quality.

[0031] The sixth lens can have positive refractive power. This allows the imaging optics system to have sufficient light-gathering capability at the image side. The image-side surface of the sixth lens can be convex near the optical axis. This helps to shorten the back focal length.

[0032] The seventh lens can have negative refractive power. This balances the refractive power of the imaging optics at the image side, improving the light-gathering quality of rays from each field of view at the imaging plane and reducing aberrations. The object-side surface of the seventh lens can be convex near the optical axis. This allows adjustment of the lens's shape, helping to correct off-axis image curvature. The image-side surface of the seventh lens can be concave near the optical axis. This allows adjustment of the lens's shape, helping to adjust the back focal length.

[0033] According to the imaging optical system disclosed herein, the image-side surface of the seventh lens may have at least one inflection point. This helps to correct image curvature and distortion in the imaging optical system while simultaneously shortening the overall length of the imaging optical system. Please refer to Figure 34, which is a schematic diagram illustrating the inflection point P on the image-side surface of the seventh lens E7 according to the first embodiment of this disclosure. Figure 34 illustrates the inflection point P on the image-side surface of the seventh lens E7 in the first embodiment of this disclosure, along with the inflection points P on the object-side surfaces of the first lens E1, the image-side surface of the first lens E1, the object-side surface of the second lens E2, the object-side surface of the third lens E3, the image-side surface of the third lens E3, the object-side surface of the fifth lens E5, the image-side surface of the fifth lens E5, the object-side surface of the sixth lens E6, the image-side surface of the sixth lens E6, and the object-side surface of the seventh lens E7, as an exemplary illustration. However, in various embodiments of this disclosure, each lens surface may have one or more inflection points.

[0034] According to the imaging optical system disclosed herein, the image-side surface of the seventh lens may have at least one critical point off-axis. This helps control peripheral image aberrations and also facilitates volume reduction. Please refer to Figure 34, which is a schematic diagram illustrating the critical point C off-axis on the image-side surface of the seventh lens E7 according to the first embodiment of this disclosure. Figure 34 illustrates the critical point C off-axis on the image-side surface of the seventh lens E7 in the first embodiment of this disclosure, along with the critical points C off-axis on the object-side surfaces of the third lens E3, fifth lens E5, fifth lens E5, sixth lens E6, and seventh lens E7, as an example. However, in various embodiments of this disclosure, each lens surface may have one or more critical points off-axis.

[0035] The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL, and the radius of curvature of the object-side surface of the first lens is R1, which can satisfy the following condition: -2.50 < TL / R1 < 1.00. This allows adjustment of the ratio of the total length of the imaging optical system to the radius of curvature of the object-side surface of the first lens, facilitating adjustment of the viewing angle. The following conditions can also be satisfied: -2.20 < TL / R1 < 1.00; -2.10 < TL / R1 < 0.80; -2.00 < TL / R1 < 0.70; -1.95 ≤ TL / R1 ≤ 0.61; and TL / R1 < 0.00.

[0036] The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL. The radius of curvature of the object-side surface of the second lens is R3, which satisfies the following condition: -2.50 < TL / R3 < 2.00. This allows adjustment of the ratio of the total length of the imaging optical system to the radius of curvature of the object-side surface of the second lens, helping to adjust the surface shape and refractive power of the second lens to improve the central imaging quality. The following conditions can also be satisfied: -2.50 < TL / R3 < 1.70. The following conditions can also be satisfied: -2.30 < TL / R3 < 1.90. The following conditions can also be satisfied: -2.20 < TL / R3 < 1.70. The following conditions can also be satisfied: -2.14 ≤ TL / R3 ≤ 1.58. The following condition can also be satisfied: TL / R3 < 0.00.

[0037] The optical axis spacing between the first and second lenses is T12, between the second and third lenses is T23, between the third and fourth lenses is T34, between the fourth and fifth lenses is T45, between the fifth and sixth lenses is T56, and between the sixth and seventh lenses is T67. This satisfies the following condition: 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.70. This helps to balance the lens distribution. It also satisfies the following condition: 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.60. Furthermore, it satisfies the following condition: 0.10 < (T12+T23+T56+T67) / (T34+T45) < 0.55. The following condition can also be satisfied: 0.13 ≤ (T12+T23+T56+T67) / (T34+T45) ≤ 0.49.

[0038] The sixth lens has a focal length of f6, and the seventh lens has a focal length of f7, which satisfies the following condition: 0.00 < |f6 / f7| < 1.00. This helps to balance the refractive power configuration at the image end. It also satisfies the following condition: 0.20 < |f6 / f7| < 0.90. Furthermore, it satisfies the following condition: 0.36 ≤ |f6 / f7| ≤ 0.83.

[0039] The distance between the fourth and fifth lenses on the optical axis is T45, and the distance between the sixth and seventh lenses on the optical axis is T67, which satisfies the following condition: 0.00 < T67 / T45 < 0.80. This helps to reduce the volume of the imaging optical system at the image side. It also satisfies the following conditions: 0.00 < T67 / T45 < 0.60. Furthermore, it satisfies the following conditions: 0.00 < T67 / T45 < 0.50. Finally, it satisfies the following condition: 0.06 ≤ T67 / T45 ≤ 0.42.

[0040] The total thickness of all lenses along the optical axis in an imaging optical system is ΣCT, and the total distance between all adjacent lenses along the optical axis is ΣAT. This satisfies the following condition: 3.00 < ΣCT / ΣAT < 6.50. This helps to increase the tightness of the lens arrangement. The following condition also applies: 3.50 < ΣCT / ΣAT < 6.00.

[0041] The focal length of the imaging optical system is f, the radius of curvature of the object-side surface of the fifth lens is R9, and the radius of curvature of the image-side surface of the fifth lens is R10. This satisfies the following condition: 4.00 < |f / R9| + |f / R10| < 8.00. This helps control the refractive power of the fifth lens and balance off-axis aberrations. The following condition also applies: 4.50 < |f / R9| + |f / R10| < 6.50.

[0042] The radius of curvature of the image-side surface of the fifth lens is R10, and the radius of curvature of the object-side surface of the sixth lens is R11, which can satisfy the following condition: -0.70 < R10 / R11 < 0.30. This allows adjustment of the light-traveling direction, helping to increase the imaging height. It can also satisfy the following condition: -0.55 < R10 / R11 < 0.25.

[0043] The imaging optical system disclosed herein may further include an aperture. The distance from the aperture to the imaging plane on the optical axis is SL, and the focal length of the imaging optical system is f, which satisfies the following condition: 1.40 < SL / f < 2.00. This allows adjustment of the ratio of the distance from the aperture to the imaging plane to the focal length of the imaging optical system, facilitating aperture position adjustment. The following condition may also be satisfied: 1.50 < SL / f < 1.90.

[0044] The fifth lens has a focal length of f5, and the sixth lens has a focal length of f6, satisfying the following condition: 0.70 < |f5 / f6| < 1.80. This balances the refractive power of the fifth and sixth lenses, helping to balance the convergence and divergence of light and improve the light-gathering quality across the entire field of view. It also satisfies the following condition: 0.80 < |f5 / f6| < 1.60.

[0045] The distance from the object-side surface of the first lens to the imaging plane along the optical axis is TL, and the focal length of the imaging optical system is f, which can satisfy the following condition: 1.60 < TL / f < 2.10. This helps to compress the total length of the imaging optical system and increase the viewing angle. The following condition can also be satisfied: 1.65 < TL / f < 2.05.

[0046] Half of the maximum field of view in an imaging optical system is the high field of view (HFOV), which satisfies the following condition: 0.70 < tan(HFOV) < 1.40. This allows the imaging optical system to have an appropriate field of view to meet market demands. It also satisfies the following condition: 0.80 < tan(HFOV) < 1.30.

[0047] The fourth lens has a focal length of f4, and the seventh lens has a focal length of f7, which satisfies the following condition: 0.40 < |f4 / f7| < 1.40. This balances the refractive power configuration of the imaging optical system, helping to reduce aberrations. Additionally, it also satisfies the following condition: 0.45 < |f4 / f7| < 1.20.

[0048] The radius of curvature of the object-side surface of the second lens is R3, and the radius of curvature of the image-side surface of the second lens is R4, which can satisfy the following condition: -0.50 < (R3-R4) / (R3+R4). This helps to adjust the surface shape and refractive power of the second lens. It can also satisfy the following condition: -0.40 < (R3-R4) / (R3+R4) < 10.00. Furthermore, it can also satisfy the following condition: -0.20 < (R3-R4) / (R3+R4) < 8.00.

[0049] The thickness of the second lens on the optical axis is CT2, and the thickness of the sixth lens on the optical axis is CT6, which can satisfy the following condition: 0.30 < CT6 / CT2 < 1.25. This balances the lens thickness configuration at the object-side and image-side ends of the imaging optical system, improving space utilization. The following condition can also be satisfied: 0.40 < CT6 / CT2 < 1.15.

[0050] The fourth lens has an Abbe number of V4, which satisfies the following condition: 35.0 < V4 < 75.0. This helps to balance the focusing ability of the imaging optical system for different wavelengths of light, thereby correcting chromatic aberration. It also satisfies the following condition: 40.0 < V4 < 60.0.

[0051] The distance from the object-side surface of the first lens to the imaging plane on the optical axis is TL. The maximum imaging height of the imaging optical system (which can be half the total diagonal length of the effective sensing area of ​​the electronic photosensitive element) is ImgH, which satisfies the following condition: 1.50 < TL / ImgH < 2.10. This helps to achieve a balance between compressing the total length of the imaging optical system and increasing the imaging plane. The following condition can also be satisfied: 1.60 < TL / ImgH < 2.00.

[0052] The focal length of the imaging optical system is f, the focal length of the first lens is f1, and the focal length of the second lens is f2. This satisfies the following condition: 0.50 < f / f1 + f / f2 < 3.00. This helps to provide the imaging optical system with sufficient light-gathering capability. It also satisfies the following condition: 0.70 < f / f1 + f / f2 < 2.00.

[0053] The radius of curvature of the image-side surface of the third lens is R6, and the radius of curvature of the object-side surface of the fourth lens is R7, which satisfies the following condition: -0.40 < R6 / R7 < 0.55. This helps to control the refraction angle of light in the imaging optical system. The following condition can also be satisfied: -0.30 < R6 / R7 < 0.40.

[0054] The distance between the third and fourth lenses on the optical axis is T34, and the distance between the fourth and fifth lenses on the optical axis is T45. This satisfies the following condition: 0.50 < T34 / T45 < 1.80. This helps reduce assembly difficulty. Additionally, it also satisfies the following condition: 0.60 < T34 / T45 < 1.60.

[0055] The maximum effective radius of the object-side surface of the second lens is Y2R1, and the maximum effective radius of the image-side surface of the seventh lens is Y7R2, which can satisfy the following condition: 2.20 < Y7R2 / Y2R1 < 5.00. This balances the effective diameter-to-height ratio of the image-side surface of the seventh lens and the object-side surface of the second lens, helping to widen the viewing angle. The following condition can also be satisfied: 2.70 < Y7R2 / Y2R1 < 4.00. Please refer to Figure 35, which is a schematic diagram illustrating parameters Y2R1 and Y7R2 according to the first embodiment of this disclosure.

[0056] The technical features of the imaging optical system disclosed above can be combined and configured to achieve corresponding effects.

[0057] In the imaging optical system disclosed in this invention, the lens can be made of glass or plastic. If the lens is made of glass, the freedom of refractive power configuration of the imaging optical system can be increased, and the influence of external environmental temperature changes on imaging can be reduced. Glass lenses can be manufactured using techniques such as grinding or molding. If the lens is made of plastic, production costs can be effectively reduced. Furthermore, spherical or aspherical (ASP) surfaces can be incorporated into the lens surface. Spherical lenses reduce manufacturing difficulty, while aspherical surfaces provide more controllable variables to reduce aberrations, decrease the number of lenses, and effectively reduce the overall length of the imaging optical system disclosed in this invention. Further, aspherical surfaces can be manufactured using methods such as plastic injection molding or molding glass lenses.

[0058] In the imaging optical system disclosed in this disclosure, if the lens surface is aspherical, it means that all or part of the optically effective area of ​​the lens surface is aspherical.

[0059] The imaging optical system disclosed herein allows for the selective addition of additives to any (or more) lens materials to produce light absorption or interference effects, thereby altering the lens's transmittance for specific wavelengths of light and reducing stray light and color shift. For example, the additives may filter out light in the 600-800 nm wavelength range to help reduce excess red or infrared light; or they may filter out light in the 350-450 nm wavelength range to reduce excess blue or ultraviolet light. Therefore, the additives can prevent specific wavelengths of light from interfering with imaging. Furthermore, the additives can be uniformly mixed into a plastic material and manufactured into a lens using injection molding technology. Additionally, the additives can also be deposited on the lens surface as a coating to provide the aforementioned effects.

[0060] In the imaging optical system disclosed herein, if the lens surface is convex and the location of the convex surface is not defined, it means that the convex surface can be located near the optical axis of the lens surface; if the lens surface is concave and the location of the concave surface is not defined, it means that the concave surface can be located near the optical axis of the lens surface. If the refractive power, radius of curvature, or focal length of the lens is not defined in its region, it means that the refractive power, radius of curvature, or focal length of the lens can be the refractive power, radius of curvature, or focal length of the lens near the optical axis.

[0061] In the imaging optical system disclosed herein, the inflection point of the lens surface refers to the boundary point where the curvature of the lens surface changes from positive to negative. The critical point of the lens surface refers to the point of tangency on the tangent line between the plane perpendicular to the optical axis and the lens surface, and the critical point is not located on the optical axis.

[0062] In the imaging optical system disclosed herein, the imaging surface of the imaging optical system can be a plane or a curved surface with any curvature, depending on the corresponding electronic photosensitive element, especially a curved surface with a concave surface facing the object side.

[0063] In the imaging optical system disclosed herein, one or more imaging correction elements (such as planar elements) can be selectively disposed between the lens closest to the imaging plane and the imaging plane in the imaging optical path to achieve the effect of correcting image curvature (such as image distortion). The optical properties of the imaging correction element, such as curvature, thickness, refractive index, position, and surface type (convex or concave, spherical or aspherical, diffractive surface, and Fresnel surface, etc.), can be adjusted according to the requirements of the imaging device. Generally, a preferred configuration of the imaging correction element is to place a thin plano-concave element with a concave surface facing the object side near the imaging plane.

[0064] In the imaging optical system disclosed herein, at least one element with a light path reversing function, such as a prism or a mirror, can be selectively arranged between the object and the imaging surface in the imaging optical path. The prism surface or mirror surface can be a plane, spherical, aspherical, or freeform surface, providing greater spatial flexibility for the imaging optical system, allowing the thinner and lighter electronic device to be independent of the overall optical length of the imaging optical system. Further explanation is provided in Figures 36 and 37, where Figure 36 illustrates one configuration of a light path reversing element according to this disclosure in an imaging optical system, and Figure 37 illustrates another configuration of a light path reversing element according to this disclosure in an imaging optical system. As shown in Figures 36 and 37, the imaging optical system can travel along the optical path from the subject (not shown) to the imaging surface IMG, and has a first optical axis OA1, an optical path reversing element LF and a second optical axis OA2 in sequence. The optical path reversing element LF can be set between the subject and the lens group LG of the imaging optical system as shown in Figure 36, or between the lens group LG of the imaging optical system and the imaging surface IMG as shown in Figure 37. Furthermore, please refer to Figure 38, which illustrates a configuration of two optical path reversing elements according to this disclosure in an imaging optical system. As shown in Figure 38, the imaging optical system can also have a first optical axis OA1, a first optical path reversing element LF1, a second optical axis OA2, a second optical path reversing element LF2, and a third optical axis OA3 along the optical path from the subject (not shown) to the imaging plane IMG. The first optical path reversing element LF1 is positioned between the subject and the lens group LG of the imaging optical system, and the second optical path reversing element LF2 is positioned between the lens group LG and the imaging plane IMG. The direction of light travel along the first optical axis OA1 can be the same as the direction of light travel along the third optical axis OA3, as shown in Figure 38. The imaging optical system can also selectively be configured with more than three optical path reversing elements. This disclosure is not limited to the type, number, and position of the optical path reversing elements shown in the figures.

[0065] The imaging optical system disclosed herein may include at least one aperture stop, which may be located before the first lens, between the lenses, or after the last lens. The aperture stop may be of the type such as a glare stop or a field stop, and may be used to reduce stray light and help improve image quality.

[0066] In the imaging optical system disclosed in this invention, the aperture can be configured as a front aperture or a center aperture. A front aperture means the aperture is positioned between the subject and the first lens, while a center aperture means the aperture is positioned between the first lens and the imaging plane. A front aperture allows for a longer distance between the exit pupil and the imaging plane, resulting in a telecentric effect and increasing the efficiency of image reception by the CCD or CMOS sensor. A center aperture helps to widen the viewing angle of the imaging optical system.

[0067] This disclosure may appropriately incorporate a variable aperture element, which can be a mechanical component or a light-regulating element, capable of electrically or by electrical signals controlling the size and shape of the aperture. The mechanical component may include movable parts such as a blade assembly or a shielding plate; the light-regulating element may include a filter element, an electrochromic material, a liquid crystal layer, or other shielding material. The variable aperture element can enhance image adjustment capabilities by controlling the amount of light entering the image or the exposure time. Furthermore, the variable aperture element can also be the aperture of this disclosure, allowing for adjustment of image quality, such as depth of field or exposure speed, by changing the aperture value.

[0068] This disclosure allows for the appropriate placement of one or more optical elements to restrict the form of light passing through the imaging optical system. These optical elements may be filters, polarizers, etc., but this disclosure is not limited thereto. Furthermore, the optical elements may be monolithic elements, composite components, or thin films, but this disclosure is not limited thereto. The optical elements can be placed between the object end, image end, or lens of the imaging optical system to control the passage of specific forms of light, thereby meeting application requirements.

[0069] The imaging optical system disclosed herein may include at least one optical lens, optical element, or carrier, at least one surface of which has a low-reflection layer, which can effectively reduce stray light generated by light reflection at the interface. The low-reflection layer may be disposed in the ineffective area of ​​the object-side surface or image-side surface of the optical lens, or on the connecting surface between the object-side surface and the image-side surface; the optical element may be a light-shielding element, an annular spacer element, a lens barrel element, a cover glass, blue glass, a filter element (color filter), a light path deflection element (reflective element), a prism, or a mirror, etc.; the carrier may be a lens mount, a microlens disposed on the photosensitive element, the periphery of the photosensitive element substrate, or a glass sheet used to protect the photosensitive element, etc.

[0070] The imaging optical system disclosed herein may further include a light-shielding element. The opening of the light-shielding element may be non-circular, and the non-circular opening may have different effective radii in different directions perpendicular to the optical axis. This allows for the use of a non-circular lens or aperture, effectively saving space and fully utilizing the light passing through the non-circular lens or aperture, thus helping to reduce stray light. The inner periphery of the light-shielding element may contain a wavy or serrated structure.

[0071] In the imaging optical system disclosed herein, the object side and image side are determined according to the optical axis direction, and the data on the optical axis are calculated along the optical axis. Furthermore, if the optical axis is deflected by an optical path deflection element, the data on the optical axis are also calculated along the optical axis.

[0072] Based on the above implementation methods, specific embodiments are presented below and described in detail with reference to the accompanying drawings.

[0073] <First Embodiment>

[0074] Please refer to Figures 1 and 2, where Figure 1 shows a schematic diagram of the imaging device according to the first embodiment of this disclosure, and Figure 2, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the first embodiment. As shown in Figure 1, the imaging device 1 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0075] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0076] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0077] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0078] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical.

[0079] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0080] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0081] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0082] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0083] The equations for the aspherical surfaces of the above lenses are expressed as follows:

[0084] X: The displacement parallel to the optical axis from the intersection of the aspherical surface and the optical axis to a point on the aspherical surface at a distance Y from the optical axis;

[0085] Y: The perpendicular distance between a point on the aspherical curve and the optical axis;

[0086] R: Radius of curvature;

[0087] k: cone coefficient; and

[0088] Ai: The i-th order aspherical coefficient.

[0089] In the imaging optical system of the first embodiment, the focal length of the imaging optical system is f, the aperture value (F-number) of the imaging optical system is Fno, half of the maximum angle of view of the imaging optical system is HFOV, and the maximum angle of view of the imaging optical system is FOV, with the following values: f = 6.98 mm, Fno = 1.80, HFOV = 45.0 degrees, and FOV = 90.0 degrees.

[0090] The distance on the optical axis from the object-side surface of the first lens E1 to the imaging plane IMG is TL, and the maximum imaging height of the imaging optical system is ImgH, which satisfies the following condition: TL / ImgH = 1.82.

[0091] The distance on the optical axis from the object-side surface of the first lens E1 to the imaging plane IMG is TL, and the focal length of the imaging optical system is f, which satisfies the following condition: TL / f = 1.84.

[0092] The distance from the aperture ST to the imaging plane IMG on the optical axis is SL, and the focal length of the imaging optical system is f, which satisfies the following condition: SL / f = 1.65.

[0093] The distance from the object-side surface of the first lens E1 to the imaging plane IMG on the optical axis is TL, and the radius of curvature of the object-side surface of the first lens E1 is R1, which satisfies the following condition: TL / R1 = -0.69.

[0094] The distance from the object-side surface of the first lens E1 to the imaging plane IMG on the optical axis is TL, and the radius of curvature of the object-side surface of the second lens E2 is R3, which satisfies the following condition: TL / R3 = -0.58.

[0095] Half of the maximum field of view in the imaging optical system is called HFOV, which satisfies the following condition: tan(HFOV) = 1.00.

[0096] The focal length of the imaging optical system is f, the focal length of the first lens E1 is f1, and the focal length of the second lens E2 is f2. They satisfy the following condition: f / f1 + f / f2 = 1.27.

[0097] The focal length of the fourth lens E4 is f4, and the focal length of the seventh lens E7 is f7. They satisfy the following condition: |f4 / f7| = 0.87.

[0098] The focal length of the fifth lens E5 is f5, and the focal length of the sixth lens E6 is f6. They satisfy the following condition: |f5 / f6| = 1.21.

[0099] The focal length of the sixth lens E6 is f6, and the focal length of the seventh lens E7 is f7. They satisfy the following condition: |f6 / f7| = 0.64.

[0100] The focal length of the imaging optical system is f, the radius of curvature of the object-side surface of the fifth lens E5 is R9, and the radius of curvature of the image-side surface of the fifth lens E5 is R10. They satisfy the following condition: |f / R9|+|f / R10| = 5.76.

[0101] The radius of curvature of the image-side surface of the third lens E3 is R6, and the radius of curvature of the object-side surface of the fourth lens E4 is R7, which satisfies the following condition: R6 / R7 = -0.25.

[0102] The radius of curvature of the image-side surface of the fifth lens E5 is R10, and the radius of curvature of the object-side surface of the sixth lens E6 is R11, which satisfies the following condition: R10 / R11 = -0.39.

[0103] The radius of curvature of the object-side surface of the second lens E2 is R3, and the radius of curvature of the image-side surface of the second lens E2 is R4, which satisfies the following condition: (R3-R4) / (R3+R4) = 0.63.

[0104] The total thickness of all lenses in the imaging optical system along the optical axis is ΣCT, and the total distance between all adjacent lenses along the optical axis is ΣAT, satisfying the following condition: ΣCT / ΣAT = 4.50. In this embodiment, the distance between two adjacent lenses along the optical axis refers to the distance between two adjacent mirror surfaces of two adjacent lenses along the optical axis. In this embodiment, ΣCT is the total thickness of the first lens E1, second lens E2, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, and seventh lens E7 along the optical axis. In this embodiment, ΣAT is the total distance between any two adjacent lenses among the first lens E1, second lens E2, third lens E3, fourth lens E4, fifth lens E5, sixth lens E6, and seventh lens E7 along the optical axis.

[0105] The thickness of the second lens E2 on the optical axis is CT2, and the thickness of the sixth lens E6 on the optical axis is CT6, which satisfies the following condition: CT6 / CT2 = 0.65.

[0106] The optical axis spacing between the first lens E1 and the second lens E2 is T12; the optical axis spacing between the second lens E2 and the third lens E3 is T23; the optical axis spacing between the third lens E3 and the fourth lens E4 is T34; the optical axis spacing between the fourth lens E4 and the fifth lens E5 is T45; the optical axis spacing between the fifth lens E5 and the sixth lens E6 is T56; and the optical axis spacing between the sixth lens E6 and the seventh lens E7 is T67. These conditions satisfy the following condition: (T12 + T23 + T56 + T67) / (T34 + T45) = 0.20.

[0107] The distance between the third lens E3 and the fourth lens E4 on the optical axis is T34, and the distance between the fourth lens E4 and the fifth lens E5 on the optical axis is T45. They satisfy the following condition: T34 / T45 = 1.13.

[0108] The distance between the fourth lens E4 and the fifth lens E5 on the optical axis is T45, and the distance between the sixth lens E6 and the seventh lens E7 on the optical axis is T67, which satisfies the following condition: T67 / T45 = 0.07.

[0109] The Abbe number of the fourth lens E4 is V4, which satisfies the following condition: V4 = 56.0.

[0110] The maximum effective radius of the object-side surface of the second lens E2 is Y2R1, and the maximum effective radius of the image-side surface of the seventh lens E7 is Y7R2, which satisfies the following condition: Y7R2 / Y2R1 = 3.01.

[0111] Please refer to Table 1A and Table 1B below.

[0112] Table 1A, First Embodiment f (focal length) = 6.98 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -18.6639 (ASP) 1.542 Glass 1.762 40.1 10.38 2 -5.7543 (ASP) -0.175 3 aperture flat 0.347 4 Second lens -22.0743 (ASP) 1.780 plastic 1.544 56.0 11.58 5 -5.0417 (ASP) 0.050 6 Third lens 15.3280 (ASP) 0.600 plastic 1.615 25.3 -10.22 7 4.3922 (ASP) 0.495 8 aperture flat 0.341 9 Fourth lens -17.8571 (ASP) 1.662 plastic 1.544 56.0 9.72 10 -4.2143 (ASP) 0.741 11 Fifth lens -1.8895 (ASP) 0.750 plastic 1.615 25.3 -8.66 12 -3.3701 (ASP) 0.050 13 Sixth lens 8.6462 (ASP) 1.156 plastic 1.544 56.0 7.17 14 -6.7706 (ASP) 0.050 15 Seventh Lens 2.9298 (ASP) 1.048 plastic 1.545 56.1 -11.15 16 1.7271 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.713 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.448 mm.

[0113] Table 1B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -8.08092E+01 -1.47538E+00 A4 = -2.35348E-03 8.64684E-03 9.27201E-03 -6.24487E-03 A6 = 2.19839E-04 -1.11083E-03 -2.24544E-03 3.60031E-06 A8 = 4.91882E-06 1.39837E-04 2.65165E-04 -1.51478E-05 A10 = - - -2.76402E-05 -5.52241E-06 surface 6 7 9 10 k = 1.04274E+01 -3.48348E+00 3.45814E+01 -1.89402E+00 A4 = -1.04798E-02 -2.42370E-03 -1.14598E-03 -7.87072E-03 A6 = -2.61822E-05 -3.08919E-04 3.49394E-04 2.63366E-04 A8 = 1.48436E-05 5.93274E-05 -9.27510E-05 1.58515E-04 A10 = -8.22009E-07 -4.98234E-06 5.98816E-06 -2.51421E-05 A12 = - - - 1.08923E-06 Surface 11 12 13 14 k = -7.48200E-01 -6.67726E-01 1.12056E+00 -2.04531E+01 A4 = [[ID=五十一]] 1.76022E-02 -2.17376E-03 7.54778E-03 2.86283E-02 A6 = -6.27572E-05 1.32410E-03 -1.08865E-03 -3.55115E-03 A8 = 1.51905E-04 -1.25015E-04 3.05360E-05 2.09134E-04 A十 = -1.69551E-05 9.21194E-06 It should be noted that in the above translation, there is an error in the original text where "A十" in line 79 should be "A10". The translation is adjusted accordingly.-3.28744E-09 -6.13111E-06 A12 = 6.49297E-07 -2.69873E-07 -5.63281E-09 6.93931E-08 surface 15 16 k = -3.49241E+00 -3.15651E+00 A4 = -9.13623E-03 -6.84446E-03 A6 = 2.60844E-04 3.79258E-04 A8 = 1.53411E-05 -1.17910E-05 A10 = -2.75069E-07 2.00166E-07 A12 = -4.90665E-08 -1.87801E-09 A14 = 1.88856E-09 1.37464E-11 A16 = -1.89138E-11 -1.39470E-13

[0114] Table 1A shows the detailed structural data of the first embodiment in Figure 1, where the units for radius of curvature, thickness, and focal length are millimeters (mm), and surfaces 0 to 19 sequentially represent the surfaces from the object side to the image side. Table 1B shows the aspherical data in the first embodiment, where k is the cone coefficient in the aspherical curve equation, and A4 to A16 represent the 4th to 16th order aspherical coefficients of each surface. Furthermore, the tables for the following embodiments are corresponding schematic diagrams and aberration curves for each embodiment. The definitions of the data in the tables are the same as those in Tables 1A and 1B of the first embodiment, and will not be repeated here.

[0115] <Second Embodiment>

[0116] Please refer to Figures 3 and 4, where Figure 3 illustrates a schematic diagram of the imaging device according to the second embodiment of this disclosure, and Figure 4, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the second embodiment. As shown in Figure 3, the imaging device 2 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0117] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0118] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0119] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical, and its image-side surface has a point of inflection.

[0120] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has a point of inflection.

[0121] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its image-side surface has a critical point off-axis.

[0122] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has one inflection point, and its image-side surface has two inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0123] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has three inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0124] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0125] Please refer to Table 2A and Table 2B below.

[0126] Table 2A, Second Embodiment f (focal length) = 6.94 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.2 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -91.6430 (ASP) 1.022 Glass 1.834 37.2 9.17 2 -7.0936 (ASP) -0.149 3 aperture flat 0.216 4 Second lens -14.6671 (ASP) 2.077 plastic 1.534 56.0 9.34 5 -3.9071 (ASP) 0.050 6 Third lens -11.6279 (ASP) 0.609 plastic 1.614 26 -7.16 7 7.2028 (ASP) 0.315 8 aperture flat 0.266 9 Fourth lens -30.2846 (ASP) 1.656 plastic 1.545 56.1 9.01 10 -4.3051 (ASP) 0.709 11 Fifth lens -1.8876 (ASP) 0.700 plastic 1.584 28.2 -9.52 12 -3.2481 (ASP) 0.050 13 Sixth lens 7.9233 (ASP) 1.211 plastic 1.545 56.1 7.54 14 -8.0680 (ASP) 0.130 15 Seventh Lens 2.7901 (ASP) 1.000 plastic 1.562 44.6 -10.94 16 1.6716 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.739 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.476 mm.

[0127] Table 2B, Aspheric Coefficient surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -3.44922E+01 -1.89055E+00 A4 = -2.72333E-03 7.07019E-03 8.92654E-03 -2.04528E-03 A6 = 2.65444E-04 -8.15133E-04 -2.03705E-03 -1.24672E-03 A8 = 1.75924E-05 1.16801E-04 2.82719E-04 1.05194E-04 A10 = - - -4.57945E-05 -1.13847E-05 surface 6 7 9 10 k = -7.03116E+01 -2.91345E+00 5.58118E+01 -2.63042E+00 A4 = -8.87246E-03 -2.98751E-03 -2.24062E-04 -7.01723E-03 A6 = 5.54394E-04 1.69804E-04 -1.46566E-04 1.56661E-04 A8 = -1.88864E-04 -5.38048E-05 -5.70476E-05 1.34900E-04 A10 = 1.44371E-05 3.65237E-06 7.36622E-06 -1.75817E-05 A12 = - - - 6.27459E-07 surface 11 12 13 14 k = -7.47923E-01 -6.71492E-01 -3.97653E-01 -1.96941E+01 A4 = 1.79792E-02 -3.76303E-03 7.09384E-03 3.14393E-02 A6 = -2.42687E-04 1.83794E-03 -8.41218E-04 -3.89114E-03 A8 = 1.94318E-04 -2.05294E-04 -4.80596E-06 2.26322E-04 A10 = -2.112S9E-05 1.50690E-05 1.89395E-06 -6.46624E-06 A12 = 7.78299E-07 -4.25672E-07 <00009,40> -4.57087E-08 7.04351E-08 surface 15 16 k = -4.13886E+00 -2.97756E+00 A4 = Note: There seems to be a small error in the translation of "1.94318E-04" in line where it was translated as "1.94318E-04" instead of "1.94318E-04" and in line where "2.112S9E-05" should probably be "2.11259E-05". These are likely just typos in the original text presentation. -5.65085E-03 -7.15642E-03 A6 = -3.50358E-04 3.68211E-04 A8 = 6.84311E-05 -9.58280E-06 A10 = -2.73829E-06 7.19507E-08 A12 = 1.29113E-08 2.60837E-09 A14 = 1.15504E-09 -7.02736E-11 A16 = -1.66147E-11 4.81309E-13

[0128] In the second embodiment, the equation of the aspherical curve is expressed in the form of the first embodiment. Furthermore, the definitions described in Table 2C are the same as those in the first embodiment, and will not be repeated here.

[0129] Table 2C, Polynomial Data f [millimeters] 6.94 |f6 / f7| 0.69 Fno 1.80 |f / R9|+|f / R10| 5.82 HFOV [degrees] 45.2 R6 / R7 -0.24 FOV [degrees] 90.4 R10 / R11 -0.41 TL / ImgH 1.75 (R3 - R4) / (R3 + R4) 0.58 TL / f 1.77 [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0131] Please refer to Figures 5 and 6, where Figure 5 shows a schematic diagram of the imaging device according to the third embodiment of this disclosure, and Figure 6, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the third embodiment. As shown in Figure 5, the imaging device 3 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0132] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0133] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical, and its object-side surface has a point of inflection.

[0134] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0135] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point.

[0136] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0137] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0138] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has three critical points off-axis, and its image-side surface has one critical point off-axis.

[0139] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0140] Please refer to Table 3A and Table 3B below.

[0141] Table 3A, Third Embodiment f (focal length) = 6.86 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.4 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -8.5705 (ASP) 1.573 Glass 1.816 46.6 214.58 2 -8.8444 (ASP) 0.085 3 aperture flat 0.096 4 Second lens 9.8039 (ASP) 1.850 plastic 1.544 56.0 7.71 5 -6.8473 (ASP) 0.231 6 Third lens 8.7363 (ASP) 0.600 plastic 1.587 28.3 -12.8 7 3.9372 (ASP) 0.680 8 aperture flat 0.090 9 Fourth lens 21.4936 (ASP) 1.837 plastic 1.544 56.0 9.78 10 -6.8628 (ASP) 0.851 11 Fifth lens -1.8842 (ASP) 0.750 plastic 1.639 23.5 -8.04 12 -3.4376 (ASP) 0.050 13 Sixth lens 7.8827 (ASP) 1.244 plastic 1.544 56.0 6.30 14 -5.7190 (ASP) 0.050 15 Seventh Lens 3.0485 (ASP) 1.036 plastic 1.562 44.6 -10.87 16 1.7850 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.687 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.818 mm.

[0142] Table 3B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -5.19657E+01 -5.21483E+00 A4 = 7.15733E-04 2.98915E-03 6.72771E-03 -4.01320E-03 A6 = 1.23974E-04 -3.15490E-05 -1.74197E-03 -5.98120E-04 A8 = -3.52277E-06 2.09386E-05 2.41636E-04 8.95215E-05 A10 = - - -2.31480E-05 -1.00769E-05 surface 6 7 9 10 k = 7.74284E+00 -2.83698E+00 -3.55886E+00 -2.47964E+00 A4 = -7.97264E-03 -2.96057E-03 -1.68315E-03 -7.04143E-03 A6 = -3.81296E-04 1.52928E-04 4.97422E-04 4.17999E-04 A8 = 4.30058E-05 -1.50721E-05 -9.02264E-05 5.42924E-05 A10 = -5.90701E-06 -5.95595E-07 4.67979E-06 -1.02812E-05 A12 = - - - 4.85249E-07 surface 11 12 13 14 k = -7.48393E-01 -7.23506E-01 8.81768E-01 -9.94867E+00 A4 = 1.77511E-02 -3.11557E-04 5.73825E-03 2.63767E-02 A6 = -1.85650E-04 7.14557E-04 -8.80255E-04 -3.15594E-03 A8 = 1.48728E-04 -2.64787E-06 2.92673E-05 1.83229E-04 A10 = -1.50291E-05 -4.72650E-07 -6.12534E-07 -5.34528E-06 A12 = 5.52544E-07 -1.78161E-08 1.15881E-08 6.05582E-08 Surface 15 16 k = -3.89421E+00 -3.28697E+00 A4 = -9.28334E-03 -7.34309E-03 A6 = 1.58715E-04 3.98770E-04 A8 = 2.11601E-05 <000​​​​​​1.50699E-07 -1.39762E-07 A12 = -9.72546E-08 1.14612E-08 A14 = 3.49982E-09 -2.27205E-10 A16 = -3.73022E-11 1.56294E-12

[0143] In the third embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 3C are the same as in the first embodiment and will not be repeated here.

[0144] Table 3C, Polynomial Data f [millimeters] 6.86 |f6 / f7| 0.58 Fno 1.80 |f / R9|+|f / R10| 5.64 HFOV [degree] 45.4 R6 / R7 0.18 FOV [degree] 90.9 R10 / R11 -0.44 TL / ImgH 1.90 (R3-R4) / (R3+R4) 5.63 TL / f 1.96 ΣCT / ΣAT 4.17 SL / f 1.71 CT6 / CT2 0.67 TL / R1 -1.57 (T12+T23+T56+T67) / (T34+T45) 0.32 TL / R3 1.37 T34 / T45 0.90 tan(HFOV) 1.02 T67 / T45 0.06 f / f1+f / f2 0.92 V4 56.0 |f4 / f7| 0.90 Y7R2 / Y2R1 2.80 |f5 / f6| 1.28 - -

[0145] <Fourth Implementation Example>

[0146] Please refer to Figures 7 and 8, where Figure 7 is a schematic diagram of the imaging device according to the fourth embodiment of this disclosure, and Figure 8 shows the spherical aberration, astigmatism, and distortion curves of the fourth embodiment from left to right. As shown in Figure 7, the imaging device 4 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system includes, from the object side to the image side, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system contains seven lenses (E1, E2, E3, E4, E5, E6, E7), and there are no other interleaved lenses between each lens.

[0147] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0148] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0149] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0150] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0151] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0152] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0153] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0154] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0155] Please refer to Table 4A and Table 4B below.

[0156] Table 4A, Fourth Embodiment f (focal length) = 7.54 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 46.3 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -36.8267 (ASP) 1.903 Glass 1.775 50.3 10.43 2 -6.7831 (ASP) -0.166 3 aperture flat 0.318 4 Second lens -19.5862 (ASP) 1.659 plastic 1.544 56.0 18.98 5 -6.9634 (ASP) 0.053 6 Third lens 10.0737 (ASP) 0.640 plastic 1.639 23.5 -14.66 7 4.7329 (ASP) 0.640 8 aperture flat 0.290 9 Fourth lens -63.5066 (ASP) 1.795 plastic 1.544 56.0 10.59 10 -5.3367 (ASP) 0.627 11 Fifth lens -2.0257 (ASP) 0.757 plastic 1.615 25.3 -9.64 12 -3.5138 (ASP) 0.053 13 Sixth lens 9.4178 (ASP) 1.107 plastic 1.544 56.0 9.98 14 -12.2921 (ASP) 0.261 15 Seventh Lens 3.3755 (ASP) 1.314 plastic 1.551 44.8 -17.1 16 2.1415 (ASP) 1.600 17 Filter element flat 0.224 Glass 1.517 64.2 - 18 flat 0.572 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 3.386 mm.

[0157] Table 4B, Aspheric Coefficient surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -6.46578E+01 -3.74771E+00 A4 = -2.19476E-03 5.18427E-03 5.79861E-03 -3.59166E-03 A6 = 9.46908E-05 -5.04046E-04 -9.49573E-04 -4.96724E-04 A8 = 2.73956E-06 4.80310E-05 7.01729E-05 6.16894E-05 A10 = - - -6.08961E-06 -5.38018E-06 surface 6 7 9 10 k = 7.40823E+00 -2.99815E+00 9.00000E+01 -3.31533E+00 A4 = -6.16700E-03 -2.10472E-03 -8.89027E-04 -4.23699E-03 A6 = -4.07753E-04 -1.20984E-04 2.37643E-05 -6.62830E-04 A8 = 3.73164E-05 1.63650E-05 -1.22880E-05 2.15835E-04 A10 = -1.50511E-06 -1.07120E-06 9.06184E-07 -1.78157E-05 A12 = - - - 4.91829E-07 surface 11 12 13 14 k = -7.49010E-01 -6.73003E-01 9.43842E-01 -1.69396E+01 A4 = 1.58998E-02 -2.58864E-03 6.49826E-03 2.22879E-02 A6 = -9.23553E-04 1.41666E-03 -7.96703E-04 -2.40271E-03 A8 = 2.26172E-04 -1.44416E-04 1.88386E-05 1.21845E-04 A10 = -1.74483E-05 8.70145E-06 -7.02106E-10 -3.03139E-06 A12 = 4.91636E-07 -1.99784E-07 -2.39514E-09 2.87956E-08 surface 15 16 k = -4.27120E+00 -3.18954E+00 A4 = -7.51831E-03 -5.97073E-03 A6 = 2.48315E-04 3.50234E-04 A8 = -2.33910E-06 -1.31634E-05 A10 = 8.19792E-07 3.23276E-07 A12 = -6.05063E-08 -5.17760E-09 A14 = 1.46338E-09 4.90602E-11 A16 = -1.16811E-11 -2.12438E-13

[0158] In the fourth embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 4C are the same as in the first embodiment and will not be repeated here.

[0159] Table 4C, Polynomial Data f [millimeters] 7.54 |f6 / f7| 0.58 Fno 1.80 |f / R9|+|f / R10| 5.86 HFOV [degree] 46.3 R6 / R7 -0.07 FOV [degree] 92.6 R10 / R11 -0.37 TL / ImgH 1.71 (R3-R4) / (R3+R4) 0.48 TL / f 1.81 ΣCT / ΣAT 4.42 SL / f 1.58 CT6 / CT2 0.67 TL / R1 -0.37 (T12+T23+T56+T67) / (T34+T45) 0.33 TL / R3 -0.70 T34 / T45 1.48 tan(HFOV) 1.05 T67 / T45 0.42 f / f1+f / f2 1.12 V4 56.0 |f4 / f7| 0.62 Y7R2 / Y2R1 3.04 |f5 / f6| 0.97 - -

[0160] <Fifth Embodiment>

[0161] Please refer to Figures 9 and 10, where Figure 9 illustrates a schematic diagram of the imaging device according to the fifth embodiment of this disclosure, and Figure 10, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the fifth embodiment. As shown in Figure 9, the imaging device 5 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0162] The first lens E1 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0163] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical.

[0164] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0165] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0166] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0167] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has one inflection point, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0168] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0169] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0170] Please refer to Table 5A and Table 5B below.

[0171] Table 5A, Fifth Embodiment f (focal length) = 6.68 mm, fno (aperture value) = 1.60, HFOV (half angle of view) = 45.9 degrees surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -22.6711 (ASP) 1.175 plastic 1.587 28.3 13.91 2 -6.1185 (ASP) -0.206 3 aperture flat 0.261 4 Second lens -29.0740 (ASP) 1.767 plastic 1.544 56.0 14.64 5 -6.3846 (ASP) 0.050 6 Third lens 9.3076 (ASP) 0.670 plastic 1.642 22.5 -12.30 7 4.1503 (ASP) 0.600 8 aperture flat 0.026 9 Fourth lens 18.3436 (ASP) 1.757 plastic 1.544 56.0 10.14 10 -7.6191 (ASP) 0.820 11 Fifth lens -1.8924 (ASP) 0.689 plastic 1.661 20.3 -8.94 12 -3.1875 (ASP) 0.050 13 Sixth lens 6.9287 (ASP) 1.132 plastic 1.545 56.1 7.33 14 -8.9008 (ASP) 0.050 15 Seventh Lens 2.6409 (ASP) 1.153 plastic 1.562 44.6 -18.42 16 1.7736 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.719 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.989 mm.

[0172] Table 5B, Aspherical Coefficient surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 3.57293E+01 -1.42959E+00 A4 = -2.72624E-03 7.81978E-03 6.17462E-03 -5.77453E-03 A6 = 3.59764E-04 -8.50314E-04 -1.82797E-03 -4.78169E-04 A8 = 7.86693E-07 1.20548E-04 2.36714E-04 7.91108E-05 A10 = - - -2.64233E-05 -1.01906E-05 surface 6 7 9 10 k = 7.41416E+00 -3.47862E+00 -8.99966E+01 -2.53712E+00 A4 = -8.68517E-03 -2.80445E-03 -1.70209E-03 -6.59852E-03 A6 = -3.09570E-04 -3.17796E-05 4.14443E-04 3.22073E-05 A8 = 4.01751E-05 1.01700E-05 -7.08961E-05 1.48078E-04 A10 = -3.31853E-06 -1.79141E-06 3.04312E-06 -1.73801E-05 A12 = - - - 5.89332E-07 surface 11 12 13 14 k = -7.50496E-01 -7.20628E-01 3.03240E-01 -1.15965E+01 A4 = 1.95669E-02 -3.52800E-03 5.96216E-03 2.75560E-02 A6 = -1.23510E-03 1.60445E-03 -8.83851E-04 -3.35855E-03 A8 = 3.32198E-04 -1.48834E-04 2.68253E-05 1.95928E-04 A10 = -2.82008E-05 1.09714E-05 -5.09283E-07 -5.75266E-06 A12 = 8.84272E-07 -3.33697E-07 8.49806E-09 6.61462E-08 surface 15 16 k = -3.32707E+00 -2.93137E+00 A4 = -8.91212E-03 -6.17074E-03 A6 = 3.73991E-04 1.97782E-04 A8 = -4.55983E-05 1.23511E-05 A10 = 7.33396E-06 -1.52711E-06 A12 = -5.01884E-07 6.87511E-08 A14 = 1.62187E-08 -1.65239E-09 A16 = -2.48277E-10 2.09866E-11 A18 = 1.44310E-12 -1.11237E-13

[0173] In the fifth embodiment, the equation of the aspherical curve is expressed in the form of the first embodiment. Furthermore, the definitions described in Table 5C are the same as those in the first embodiment, and will not be repeated here.

[0174] Table 5C, Polynomial Data f [millimeters] 6.68 |f6 / f7| 0.40 Fno 1.60 |f / R9| + |f / R10| 5.63 HFOV [degrees] 45.9 R6 / R7 0.23 FOV [degrees] 91.7 R10 / R11 -0.46 TL / ImgH 1.76 (R3 - R4) / (R3 + R4) 0.64 TL / f 1.86 [[ID=3,4]] ΣCT / ΣAT 5.05 SL / f 1.71 CT6 / CT2 0.64 TL / R1 -0.55 (T12 + T23 + T56 + T67) / (T34 + T45) 0.14 TL / R3 -0.43 [[ID=,57]] T34 / T45 0.7 ,6 tan(HFOV) 1.03 T67 / T45 0.06 f / f1 + f / f2 0.94 V4 56.0 |f4 / f7| 0.55 Y7R2 / Y2R1 2.89 |f5 / f6| 1.22 - - It should be noted that there may be some inaccuracies in the translation due to the complexity and potential ambiguity of the original text, especially in some cases where the meaning might not be fully clear without additional context. If possible, it would be beneficial to have more background information to ensure a more precise translation.

[0175] <Sixth Embodiment>

[0176] Please refer to Figures 11 and 12, where Figure 11 shows a schematic diagram of the imaging device according to the sixth embodiment of this disclosure, and Figure 12, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the sixth embodiment. As shown in Figure 11, the imaging device 6 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0177] The first lens E1 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point.

[0178] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical.

[0179] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0180] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0181] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0182] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0183] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both surfaces are aspherical. Its object-side surface has four inflection points, its image-side surface has two inflection points, its object-side surface has three critical points off-axis, and its image-side surface has one critical point off-axis.

[0184] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0185] Please refer to Table 6A and Table 6B below.

[0186] Table 6A, Sixth Embodiment f (focal length) = 6.93 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens 19.6078 (ASP) 0.894 plastic 1.567 37.4 9.05 2 -6.8235 (ASP) -0.145 3 aperture flat 0.211 4 Second lens -8.7761 (ASP) 1.550 plastic 1.544 56.0 35.25 5 -6.3954 (ASP) 0.050 6 Third lens 9.2591 (ASP) 0.712 plastic 1.660 20.4 -13.10 7 4.3339 (ASP) 0.545 8 aperture flat 0.117 9 Fourth lens 21.6542 (ASP) 1.803 plastic 1.551 44.8 10.43 10 -7.5896 (ASP) 0.677 11 Fifth lens -1.8838 (ASP) 0.600 plastic 1.669 19.5 -8.29 12 -3.2160 (ASP) 0.050 13 Sixth lens 7.0824 (ASP) 1.252 plastic 1.551 44.8 5.77 14 -5.4025 (ASP) 0.057 15 Seventh Lens 3.2550 (ASP) 1.241 plastic 1.567 37.4 -9.80 16 1.7693 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.659 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.818 mm.

[0187] Table 6B, Aspherical Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -1.26947E+01 -2.33385E+00 A4 = -3.42313E-03 6.97612E-03 5.68537E-03 -3.60869E-03 A6 = -3.89067E-06 -5.41015E-04 -9.77981E-04 -9.92792E-04 A8 = 6.51041E-05 1.08591E-04 6.06867E-05 1.13712E-04 A10 = - - -1.63521E-05 -1.16848E-05 surface 6 7 9 10 k = 8.53069E+00 -3.89897E+00 -8.23435E+01 -2.18491E+00 A4 = -9.53337E-03 -3.52745E-03 -1.34350E-03 -7.80449E-03 A6 = -2.05685E-04 1.80745E-04 3.61268E-04 5.74713E-04 A8 = 4.24440E-05 -5.51530E-06 -1.04882E-(此处原文似乎有误,推测可能是-1.04882E-04) 3.65314E-05 A10 = -5.29275E-06 -2.08749E-06 6.21562E-06 -9.17370E-06 A12 = <000242\(此处原文似乎有误,推测可能是 - - - 4.49815E-07 surface 11 12 13 14 k = -7.(此处原文似乎有误,推测可能是-7.49479E-01) -6.73201E-01 -1.96541E-02 -1.19073E+01 A4 = 1.80192E-02 -1.53448E-03 5.51081E-03 2.80174E-02 A6 = -6.61377E-04 7.55537E-04 -8.52913E-04 -3.42449E-03 A8 = 2.28394E-04 4.49649E-06 2.81006E-05 2.00178E-04 A10 = -1.94736E-05 -1.45688E-06 -6.66854E-07 -5.87559E-06 A12 = 6.16704E-07 3.09759E-08 <� 1.38060E-08 6.72421E-08 Surface 15 16 k = -3.51641E+00 -3.36709E+00 A4 = -9.16259E-03 -4.92323E-03 A6 = 2.60016E-04 9.62633E-05 A8 = -4.55799E-06 1.45734E-05 A10 = 2.39415E-06 It should be noted that there is a misspelling in the original text, the tag <� should be . This translation has been corrected accordingly. -1.25497E-06 A12 = -1.94877E-07 4.32955E-08 A14 = 5.60861E-09 -7.20975E-10 A16 = -5.50821E-11 4.73555E-12

[0188] In the sixth embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 6C are the same as in the first embodiment and will not be repeated here.

[0189] Table 6C, Polynomial Data f [millimeters] 6.93 |f6 / f7| 0.59 Fno 1.80 |f / R9|+|f / R10| 5.83 HFOV [degree] 45.0 R6 / R7 0.20 FOV [degree] 90.0 R10 / R11 -0.45 TL / ImgH 1.70 (R3-R4) / (R3+R4) 0.16 TL / f 1.73 ΣCT / ΣAT 5.15 SL / f 1.62 CT6 / CT2 0.81 TL / R1 0.61 (T12+T23+T56+T67) / (T34+T45) 0.17 TL / R3 -1.37 T34 / T45 0.98 tan(HFOV) 1.00 T67 / T45 0.08 f / f1+f / f2 0.96 V4 44.8 |f4 / f7| 1.06 Y7R2 / Y2R1 3.34 |f5 / f6| 1.44 - -

[0190] <Seventh Implementation Example>

[0191] Please refer to Figures 13 and 14, where Figure 13 is a schematic diagram of the imaging device according to the seventh embodiment of this disclosure, and Figure 14 shows the spherical aberration, astigmatism, and distortion curves of the seventh embodiment from left to right. As shown in Figure 13, the imaging device 7 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system includes, from the object side to the image side, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system contains seven lenses (E1, E2, E3, E4, E5, E6, E7), and there are no other interleaved lenses between each lens.

[0192] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0193] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0194] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0195] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0196] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0197] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has three inflection points, and its image-side surface has three inflection points. Its object-side surface has two critical points off-axis, and its image-side surface has two critical points off-axis.

[0198] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0199] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0200] Please refer to Table 7A and Table 7B below.

[0201] Table 7A, Seventh Embodiment f (focal length) = 6.97 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.5 degrees surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -30.5497 (ASP) 2.076 Glass 1.769 49.3 8.84 2 -5.7257 (ASP) -0.210 3 aperture flat 0.392 4 Second lens -15.9282 (ASP) 1.355 plastic 1.544 56.0 17.80 5 -6.2034 (ASP) 0.050 6 Third lens 9.6041 (ASP) 0.626 plastic 1.614 26 -11.01 7 3.8678 (ASP) 0.690 8 Aperture flat 0.158 9 Fourth lens 58.8235 (ASP) 1.625 plastic 1.544 56.0 8.90 10 -5.2227 (ASP) 0.653 11 Fifth lens -1.9074 (ASP) 0.700 plastic 1.642 22.5 -11.33 12 -2.9572 (ASP) 0.050 13 Sixth lens -14.9254 (ASP) 0.900 plastic 1.535 55.9 9.18 14 -3.7710 (ASP) 0.050 15 Seventh Lens 3.8257 (ASP) 1.425 plastic 1.545 56.1 -11.05 16 2.0321 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.537 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.818 mm.

[0202] Table 7B, Aspherical Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -4.72599E+01 -2.36482E+00 A4 = -2.31188E-03 8.12282E-03 7.92178E-03 -4.10450E-03 A6 = 1.06658E-04 -9.59356E-04 -1.81399E-03 -8.95597E-04 A8 = 5.00883E-06 1.06223E-04 1.81336E-04 1.41702E-04 A10 = - - -1.72955E-05 -1.52780E-05 Surface 6 7 9 10 k = 1.02255E+01 -2.85412E+00 5.50795E+01 -6.40942E+00 A4 = -8.70563E-03 -2.48171E-03 7.78139E-05 -5.62225E-03 A6 = -7.63291E-04 -2.38035E-04 2.14591E-04 -1.67198E-04 A8 = 1.49244E-04 6.46444E-05 -4.76111E-05 2.36635E-04 A10 = -1.15235E-05 -5.37834E-06 1.09832E-06 -3.18806E-05 A12 = - - - 1.31022E-06 surface 11 12 13 14 k = -7.48528E-01 -8.20183E-01 -9.00000E+01 -5.21601E+00 A4 = 1.48332E-02 -6.51408E-04 2.07509E-02 3.41686E-02 A6 = 1.08507E-03 1.79100E-03 -2.61061E-03 -3.92461E-03 A8 = -7.48906E-05 -2.33759E-04 1.50188E-04 2.17177E-04 A10 = 2.76496E-06 1.80358E-05 -5.81599E-06 -6.13659E-06 A12 = 2.18230E-08 -5.21378E-07 1.10201E-07 6.84759E-08 surface 15 16 k = -2.73666E+00 -4.46980E+00 A4 = -7.61209E-03 -1.17689E-03 A6 = 1.59237E-04 -3.21301E-04 A8 = -8.11356E-06 3.88078E-05 A10 = 2.78141E-06 -2.23791E-06 A12 = -2.04203E-07 7.05098E-08 A14 = 5.68406E-09 -1.15972E-09 A16 = -5.53509E-11 7.73650E-12

[0203] In the seventh embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 7C are the same as in the first embodiment and will not be repeated here.

[0204] Table 7C, Polynomial Data f [millimeters] 6.97 |f6 / f7| 0.83 Fno 1.80 |f / R9|+|f / R10| 6.01 HFOV [degree] 45.5 R6 / R7 0.07 FOV [degree] 91.0 R10 / R11 0.20 TL / ImgH 1.81 (R3-R4) / (R3+R4) 0.44 TL / f 1.84 ΣCT / ΣAT 4.75 SL / f 1.57 CT6 / CT2 0.66 TL / R1 -0.42 (T12+T23+T56+T67) / (T34+T45) 0.22 TL / R3 -0.80 T34 / T45 1.30 tan(HFOV) 1.02 T67 / T45 0.08 f / f1+f / f2 1.18 V4 56.0 |f4 / f7| 0.81 Y7R2 / Y2R1 2.88 |f5 / f6| 1.23 - -

[0205] <Eighth Embodiment>

[0206] Please refer to Figures 15 and 16, where Figure 15 illustrates a schematic diagram of the imaging device according to the eighth embodiment of this disclosure, and Figure 16, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the eighth embodiment. As shown in Figure 15, the imaging device 8 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0207] The first lens E1 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0208] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical.

[0209] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0210] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0211] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0212] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has one inflection point, and its image-side surface has two inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0213] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0214] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0215] Please refer to Table 8A and Table 8B below.

[0216] Table 8A, Eighth Embodiment f (focal length) = 6.06 mm, fno (aperture value) = 1.70, HFOV (half angle of view) = 50.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -9.5641 (ASP) 1.274 plastic 1.614 25.6 13.98 2 -4.7507 (ASP) -0.223 3 aperture flat 0.295 4 Second lens -45.0849 (ASP) 1.395 plastic 1.562 44.6 12.37 5 -6.0885 (ASP) 0.050 6 Third lens 9.6859 (ASP) 0.640 plastic 1.650 21.8 -10.97 7 3.9997 (ASP) 0.610 8 Aperture flat -0.053 9 Fourth lens 11.9469 (ASP) 2.011 plastic 1.544 56.0 9.86 10 -9.1549 (ASP) 0.640 11 Fifth lens -1.8915 (ASP) 0.779 plastic 1.697 16.3 -9.04 12 -3.1596 (ASP) 0.050 13 Sixth lens 6.9908 (ASP) 1.132 plastic 1.545 56.1 6.99 14 -7.8859 (ASP) 0.050 15 Seventh Lens 2.4128 (ASP) 1.000 plastic 1.614 25.6 -19.68 16 1.6940 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.649 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.899 mm.

[0217] Table 8B, Aspheric Coefficient surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 8.94791E+01 8.33644E-01 A4 = -2.66096E-03 9.51944E-03 3.91242E-03 -6.86406E-03 A6 = 3.42517E-04 -1.26488E-03 -1.71978E-03 -2.86897E-04 A8 = 7.25658E-06 2.07708E-04 1.66869E-04 5.91971E-05 A10 = - - -2.13590E-05 -1.46087E-05 surface 6 7 9 10 k = 8.28679E+00 -3.44472E+00 -2.11117E+01 -1.01294E+00 A4 = -8.14542E-03 -2.46859E-03 -1.76749E-03 -7.44724E-03 A6 = -5.03419E-04 -1.13074E-04 6.29970E-04 4.98843E-04 <0003­177> A8 = 5.13343E-05 1.33516E-05 -9.44136E-05 5.48217E-05 A10 = -3.48161E-06 -1.89598E-06 3.73939E-06 -1.00052E-05 A12 = - - - 3.63554E-07 surface 11 12 13 14 k = -7.50075E-01 -8.20791E-01 5.79303E-01 -6.51471E+00 A4 = 1.87984E-02 -3.66291E-03 6.29103E-03 2.89805E-02 A6 = -5.78045E-04 1.65088E-03 -8.40335E-04 -3.26328E-03 A8 = 2.32334E-04 -1.43013E-04 2.30946E-05 1.76011E-04 A10 = -2.20128E-05 1.06471E-05 -6.65352E-07 -4.82631E-06 A12 = 7.50295E-07 -3.34034E-07 1.63631E-08 5.18045E-08 surface 15 16 k = -2.74250E+00 -2.71307E+00 A4 = -8.73535E-03 -7.13865E-03 A6 = 2.16606E-04 2.49648E-04 A8 = -2.31605E-05 5.83012E-06 A10 = 4.75517E-06 -8.37723E-07 A12 = -3.17190E-07 2.98893E-08 A14 = 8.62959E-09 -4.86950E-10 A16 = -8.41225E-11 3.10259E-12

[0218] In the eighth embodiment, the equation of the aspherical curve is expressed in the form of the first embodiment. Furthermore, the definitions described in Table 8C are the same as those in the first embodiment, and will not be repeated here.

[0219] Table 8C, Polynomial Data f [millimeters] 6.06 |f6 / f7| 0.36 Fno 1.70 |f / R9|+|f / R10| 5.12 HFOV [degrees] 50.0 R6 / R7 0.33 FOV [degrees] 100.0 R10 / R11 -0.45 TL / ImgH 1.70 (R3 - R4) / (R3 + R4) H 0.76 TL / f 1.98 ΣCT / ΣAT 5.80 SL / f 1.81 CT6 / CT2 [[ID=4⑨]] 0.81 TL / R1 -1.26 (T12 + T23 + T56 + T67) / (T34 + T45) [[ID=5⑦]] 0.19 TL / R3 -0.27 T34 / T45 0.87 tan(HFOV) 1.19 T67 / T45 0.08 f / f1 + f / f2 0.92 V4 56.0 |f4 / f7| 0.50 Y7R2 / Y2R1 3.10 |f5 / f6| 1.29 - -

[0220] <Ninth Embodiment>

[0221] Please refer to Figures 17 and 18, where Figure 17 illustrates a schematic diagram of the imaging device according to the ninth embodiment of this disclosure, and Figure 18, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the ninth embodiment. As shown in Figure 17, the imaging device 9 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0222] The first lens E1 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0223] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical, and its object-side surface has a point of inflection.

[0224] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0225] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0226] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0227] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0228] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0229] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0230] Please refer to Table 9A and Table 9B below.

[0231] Table 9A, Ninth Embodiment f (focal length) = 7.05 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -6.8549 (ASP) 1.431 plastic 1.584 28.2 -70.78 2 -8.8496 (ASP) -0.038 3 aperture flat 0.088 4 Second lens 8.4429 (ASP) 2.198 plastic 1.544 56.0 7.12 5 -6.4976 (ASP) 0.569 6 Third lens 9.0198 (ASP) 0.550 plastic 1.587 28.3 -16.66 7 4.5877 (ASP) 0.560 8 aperture flat 0.144 9 Fourth lens 45.1186 (ASP) 1.877 plastic 1.535 55.9 11.44 10 -6.9686 (ASP) 0.815 11 Fifth lens -1.8674 (ASP) 0.600 plastic 1.650 21.8 -7.85 12 -3.3197 (ASP) 0.078 13 Sixth lens 9.0145 (ASP) 1.161 plastic 1.544 56.0 6.04 14 -4.9387 (ASP) 0.050 15 Seventh Lens 2.9374 (ASP) 1.000 plastic 1.545 56.1 -9.96 16 1.6769 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.554 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.815 mm.

[0232] Table 9B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -3.21723E+01 -4.84774E+00 A4 = 1.45630E-03 2.69137E-03 4.95266E-03 -5.35535E-03 A6 = 9.22874E-05 9.03547E-05 -1.38537E-03 -2.71086E-04 A8 = -2.80937E-06 9.17565E-06 1.73275E-04 3.91193E-05 A10 = - - -1.93390E-05 -6.11362E-06 surface 6 7 9 10 k = 7.78665E+00 -2.89490E+00 -3.18142E+01 2.50681E-01 A4 = -7.93602E-03 -2.41623E-03 -2.14114E-03 -7.22075E-03 A6 = -4.22844E-04 -1.66519E-04 3.44499E-04 8.89237E-05 A8 = 4.39455E-05 2.92000E-05 -5.71880E-05 1.09477E-04 A10 = -4.59200E-06 -3.02394E-06 1.72799E-06 -1.32074E-05 A12 = - - - 4.69544E-07 surface 11 12 13 14 k = -7.48177E-01 -6.92325E-01 1.01057E+00 -9.94298E+00 A4 = 1.70558E-02 -9.37353E-04 7.35377E-03 2.89075E-02 A6 = -5.95544E-05 1.19750E-03 -1.02326E-03 -3.53420E-03 A8 = 1.08082E-04 -7.61515E-05 2.65401E-05 2.04555E-04 A10 = -1.07876E-05 3.54184E-06 -1.13205E-07 -5.91184E-06 A12 = 4.07344E-07 -9.23146E-08 1.18846E-09 6.64489E-08 surface 15 16 k = -4.11562E+00 -3.26132E+00 A4 = -9.16358E-03 -7.16490E-03 A6 = 9.40717E-05 3.95086E-04 A8 = 2.29043E-05 -1.02897E-05 A10 = 4.71445E-07 1.58147E-08 A12 = -1.27321E-07 5.40410E-09 A14 = 4.45057E-09 -1.18063E-10 A16 = -4.75359E-11 8.12832E-13

[0233] In the ninth embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 9C are the same as in the first embodiment and will not be repeated here.

[0234] Table 9C, Polynomial Data f [millimeters] 7.05 |f6 / f7| 0.61 Fno 1.80 |f / R9|+|f / R10| 5.90 HFOV [degree] 45.0 R6 / R7 0.10 FOV [degree] 90.0 R10 / R11 -0.37 TL / ImgH 1.89 (R3 - R4) / (R3 + R4) 7.68 TL / f 1.89 ΣCT / ΣAT 3.89 SL / f 1.70 CT6 / CT2 0.53 TL / R1 -1.95 (T12 + T23 + T56 + T67) / (T34 + T45) 0.49 TL / R3 1.58 T34 / T45 0.86 tan(HFOV) 1.00 T67 / T45 0.06 f / f1 + f / f2 0.89 V4 55.9 |f4 / f7| 1.15 Y7R2 / Y2R1 2.78 |f5 / f6| 1.30 - -

[0235] <Tenth Embodiment>

[0236] Please refer to Figures 19 and 20, where Figure 19 illustrates a schematic diagram of an imaging device according to the tenth embodiment of this disclosure, and Figure 20, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the tenth embodiment. As shown in Figure 19, the imaging device 10 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0237] The first lens E1 has positive refractive power and is made of glass. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its image-side surface also has a point of inflection.

[0238] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0239] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0240] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0241] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0242] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0243] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has a critical point off-axis, and its image-side surface has a critical point off-axis.

[0244] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0245] Please refer to Table 10A and Table 10B below.

[0246] Table 10A, Tenth Embodiment f (focal length) = 6.74 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.9 degrees surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens -25.0000 (ASP) 1.980 Glass 1.769 44.8 9.66 2 -5.9248 (ASP) -0.187 3 aperture flat 0.329 4 Second lens -20.2167 (ASP) 1.381 plastic 1.544 56.0 15.95 5 -6.2176 (ASP) 0.050 6 Third lens 9.6857 (ASP) 0.604 plastic 1.598 26.4 -10.77 7 3.7783 (ASP) 0.690 8 Aperture flat 0.059 9 Fourth lens 54.8389 (ASP) 1.843 plastic 1.544 56.0 8.68 10 -5.1045 (ASP) 0.658 11 Fifth lens -1.8909 (ASP) 0.750 plastic 1.640 23.3 -8.14 12 -3.4268 (ASP) 0.050 13 Sixth lens 8.5583 (ASP) 1.137 plastic 1.544 56.0 6.63 14 -5.9401 (ASP) 0.048 15 Seventh Lens 2.8617 (ASP) 1.000 plastic 1.544 56.0 -10.52 16 1.6728 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.656 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.820 mm.

[0247] Table 10B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -6.30830E+01 -1.91854E+00 A4 = -1.88133E-03 9.22827E-03 8.30550E-03 -4.85950E-03 A6 = 1.40689E-04 -1.18119E-03 -1.96300E-03 -6.25485E-04 A8 = 3.10015E-06 1.46402E-04 1.91484E-04 8.43768E-05 A10 = - - -1.34795E-05 -1.04405E-05 surface 6 7 9 10 k = 1.03981E+01 -2.96208E+00 9.00000E+01 -2.85454E+00 A4 = -8.94742E-03 -2.33088E-03 -9.91923E-04 -8.32964E-03 A6 = -7.50087E-04 -2.66453E-04 4.03542E-04 5.39597E-04 A8 = 1.28755E-04 6.24595E-05 -8.18211E-05 1.45444E-04 A10 = -9.89044E-06 -5.27625E-06 3.81803E-06 -2.68353E-05 A12 = - - - 1.27440E-06 Surface 11 12 13 14 k = -7.48546E-01 -7.25093E-01 9.39864E-01 -1.63965E+01 A4 = 1.68490E-02 -2.67161E-03 7.40066E-03 2.90662E-02 A6 = 4.78256E-04 1.61846E-03 -1.07486E-03 -3.62720E-03 A8 = 3.75202E-05 -1.66716E-04 2.90172E-05 2.13861E-04 A10 = -6.65994E-06 1.25622E-05 -2.40384E-08 -6.26866E-06 <000​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ -1.77139E-07 A12 = -9.62556E-08 1.16875E-08 A14 = 3.49984E-09 -2.27205E-10 A16 = -3.73023E-11 1.56294E-12

[0248] In the tenth embodiment, the equation for the aspherical curve is expressed as in the first embodiment. Furthermore, the definitions in Table 10C are the same as in the first embodiment and will not be repeated here.

[0249] Table 10C, Polynomial Data f [millimeters] 6.74 |f6 / f7| 0.63 Fno 1.80 |f / R9|+|f / R10| 5.53 HFOV [degree] 45.9 R6 / R7 0.07 FOV [degree] 91.8 R10 / R11 -0.40 TL / ImgH 1.81 (R3-R4) / (R3+R4) 0.53 TL / f 1.89 ΣCT / ΣAT 5.12 SL / f 1.63 CT6 / CT2 0.82 TL / R1 -0.51 (T12+T23+T56+T67) / (T34+T45) 0.21 TL / R3 -0.63 T34 / T45 1.14 tan(HFOV) 1.03 T67 / T45 0.07 f / f1+f / f2 1.12 V4 56.0 |f4 / f7| 0.82 Y7R2 / Y2R1 2.99 |f5 / f6| 1.23 - -

[0250] <Eleventh Implementation Regulations>

[0251] Please refer to Figures 21 and 22, where Figure 21 is a schematic diagram of the imaging device according to the eleventh embodiment of this disclosure, and Figure 22 shows the spherical aberration, astigmatism, and distortion curves of the eleventh embodiment from left to right. As shown in Figure 21, the imaging device 11 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system includes, in sequence from the object side to the image side along the optical path, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging plane IMG. The electronic photosensitive element IS is disposed on the imaging plane IMG. The imaging optical system contains seven lenses (E1, E2, E3, E4, E5, E6, E7), and there are no other interleaved lenses between each lens.

[0252] The first lens E1 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its object-side surface has a critical point off-axis.

[0253] The second lens E2 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical, and its object-side surface has two inflection points.

[0254] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0255] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0256] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0257] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has one inflection point, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0258] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has four inflection points, and its image-side surface has one inflection point. Its object-side surface has three critical points off-axis, and its image-side surface has one critical point off-axis.

[0259] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0260] Please refer to Table 11A and Table 11B below.

[0261] Table 11A, Eleventh Embodiment f (focal length) = 7.34 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 43.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens 28.9113 (ASP) 0.905 plastic 1.562 44.6 6.96 2 -4.4734 (ASP) -0.283 3 aperture flat 0.333 4 Second lens -5.7863 (ASP) 1.306 plastic 1.535 55.9 -97.7 5 -7.0189 (ASP) 0.050 6 Third lens 8.4169 (ASP) 0.762 plastic 1.639 23.5 -13.07 7 4.0435 (ASP) 0.590 8 Aperture flat 0.165 9 Fourth lens 27.3767 (ASP) 1.961 plastic 1.544 56.0 9.61 10 -6.3030 (ASP) 0.833 11 Fifth lens -1.8857 (ASP) 0.626 plastic 1.615 25.3 -8.65 12 -3.2901 (ASP) 0.050 13 Sixth lens 7.6906 (ASP) 1.368 plastic 1.544 56.0 6.83 14 -6.7318 (ASP) 0.050 15 Seventh Lens 3.4588 (ASP) 1.329 plastic 1.562 44.6 -11.57 16 1.9457 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.614 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.814 mm.

[0262] Table 11B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -1.48193E+01 -3.30094E+00 A4 = -5.50192E-03 1.56010E-02 9.68946E-03 -3.27856E-03 A6 = -1.89765E-04 -2.38513E-03 -1.33261E-03 -9.48354E-04 A8 = 8.15745E-05 2.52983E-04 -7.82626E-06 9.53192E-05 A10 = - - 5.68896E-07 -9.10082E-06 surface 6 7 9 10 k = 6.67133E+00 -3.71499E+00 -5.09665E+01 -2.01945E+00 A4 = -9.75061E-03 -3.15575E-03 -1.15612E-03 -5.34743E-03 A6 = -3.02998E-04 5.95398E-06 1.34198E-04 -7.80354E-05 A8 = 5.80324E-05 1.69751E-05 -6.38653E-05 9.40862E-05 A10 = -4.24184E-06 -2.66799E-06 2.71757E-06 -9.98012E-06 A12 = - - - 3.36874E-07 surface 11 12 13 14 k = -7.50000E-01 -6.56575E-01 9.28176E-01 -9.92886E+00 A4 = 1.86717E-02 -5.99789E-04 4.35833E-03 2.55668E-02 A6 = -1.40543E-03 4.91898E-04 -7.65590E-04 -3.12584E-03 A8 = 3.65456E-04 3.20551E-05 2.36057E-05 1.85488E-04 A10 = -3.03304E-05 -2.55251E-06 -2.25860E-07 -5.52633E-06 A12 = 9.39023E-07 2.51322E-08 -1.35628E-09 6.38621E-08 surface 15 16 k = <o004376> -3.32363E+00 -3.43320E+00 A4 = -9.47274E-03 -4.95229E-03 A6 = 4.21576E-04 1.56595E-04 A8 = -2.63913E-05 5.53656E-06 A10 = 3.74723E-06 [[ID=5�7]] -6.60467E-07 A12 = -2.37069E-07 2.34175E-08 A14 = 6.23717E-09 -3.86237E-10 A16 = -5.85086E-11 It should be noted that there seems to be a misspelling in the tag `o004376` which should probably be ` `. This has been left as is in the translation to maintain consistency with the original text. 2.48493E-12

[0263] In the eleventh embodiment, the equation of the curve for the aspherical surface is expressed in the form of the first embodiment. Furthermore, the definitions in Table 11C are the same as in the first embodiment and will not be repeated here.

[0264] Table 11C, Polynomial Data f [millimeters] 7.34 |f6 / f7| 0.59 Fno 1.80 |f / R9|+|f / R10| 6.12 HFOV [degree] 43.0 R6 / R7 0.15 FOV [degree] 86.0 R10 / R11 -0.43 TL / ImgH 1.75 (R3-R4) / (R3+R4) -0.10 TL / f 1.68 ΣCT / ΣAT 4.62 SL / f 1.60 CT6 / CT2 1.05 TL / R1 0.43 (T12+T23+T56+T67) / (T34+T45) 0.13 TL / R3 -2.14 T34 / T45 0.91 tan(HFOV) 0.93 T67 / T45 0.06 f / f1+f / f2 0.98 V4 56.0 |f4 / f7| 0.83 Y7R2 / Y2R1 3.09 |f5 / f6| 1.27 - -

[0265] <Twelfth Embodiment>

[0266] Please refer to Figures 23 and 24, where Figure 23 illustrates a schematic diagram of the imaging device according to the twelfth embodiment of this disclosure, and Figure 24, from left to right, shows the spherical aberration, astigmatism, and distortion curves of the twelfth embodiment. As shown in Figure 23, the imaging device 12 includes an imaging optical system (unlabeled) and an electronic photosensitive element IS. The imaging optical system, along the optical path from the object side to the image side, includes, in sequence, a first lens E1, an aperture ST, a second lens E2, a third lens E3, an aperture stop S1, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, a filter element E8, and an imaging surface IMG. The electronic photosensitive element IS is disposed on the imaging surface IMG. The imaging optical system includes seven lenses (E1, E2, E3, E4, E5, E6, and E7), and there are no other interposed lenses between each lens.

[0267] The first lens E1 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical.

[0268] The second lens E2 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical, and its object-side surface has a point of inflection.

[0269] The third lens E3 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, its image-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0270] The fourth lens E4 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has a point of inflection, and its object-side surface has a critical point off-axis.

[0271] The fifth lens E5 has negative refractive power and is made of plastic. Its object-side surface is concave near the optical axis, and its image-side surface is convex near the optical axis. Both surfaces are aspherical. Its object-side surface has two inflection points, its image-side surface has one inflection point, and its image-side surface has a critical point off-axis.

[0272] The sixth lens E6 has positive refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is convex near the optical axis. Both of its surfaces are aspherical. Its object-side surface has two inflection points, and its image-side surface has three inflection points. Its object-side surface has one critical point off-axis, and its image-side surface has two critical points off-axis.

[0273] The seventh lens E7 has negative refractive power and is made of plastic. Its object-side surface is convex near the optical axis, and its image-side surface is concave near the optical axis. Both surfaces are aspherical. Its object-side surface has four inflection points, its image-side surface has two inflection points, its object-side surface has three critical points off-axis, and its image-side surface has one critical point off-axis.

[0274] The filter element E8 is made of glass and is located between the seventh lens E7 and the imaging surface IMG. It does not affect the focal length of the imaging optical system.

[0275] Please refer to Table 12A and Table 12B below.

[0276] Table 12A, Twelfth Embodiment f (focal length) = 6.95 mm, fno (aperture value) = 1.80, HFOV (half angle of view) = 45.0 degrees. surface radius of curvature thickness Material Refractive index Abbe number focal length 0 Subject unlimited unlimited 1 First lens 34.7289 (ASP) 0.676 plastic 1.650 21.8 120.9 2 61.7284 (ASP) 0.135 3 aperture flat 0.090 4 Second lens 14.0790 (ASP) 1.754 plastic 1.551 44.8 8.31 5 -6.4787 (ASP) 0.061 6 Third lens 9.0180 (ASP) 0.720 plastic 1.642 22.5 -13.75 7 4.3211 (ASP) 0.546 8 Aperture flat 0.152 9 Fourth lens 24.1499 (ASP) 1.827 plastic 1.544 56.0 10.28 10 -7.0855 (ASP) 0.678 11 Fifth lens -1.8609 (ASP) 0.600 plastic 1.642 22.5 -8.70 12 -3.1437 (ASP) 0.050 13 Sixth lens 7.1103 (ASP) 1.335 plastic 1.544 56.0 5.88 14 -5.4385 (ASP) 0.050 15 Seventh Lens 3.0681 (ASP) 1.150 plastic 1.551 44.8 -9.44 16 1.6725 (ASP) 1.500 17 Filter element flat 0.210 Glass 1.517 64.2 - 18 flat 0.713 19 Imaging surface flat - The reference wavelength (d-line) is 587.6 nm. The effective radius of surface 8 (aperture S1) is 2.817 mm.

[0277] Table 12B, Aspheric Coefficients surface 1 2 4 5 k = 0.00000E+00 0.00000E+00 -9.00000E+01 -2.00678E+00 A4 = -6.09748E-04 1.41397E-03 3.19200E-03 -2.95292E-03 A6 = 2.89824E-04 2.54517E-04 -1.30193E-03 -1.13766E-03 A8 = -4.57585E-07 4.83978E-05 1.85045E-04 1.35293E-04 A10 = - - -2.90953E-05 -1.60509E-05 surface 6 7 9 10 k = 8.82826E+00 -4.01605E+00 -6.26490E+01 -2.40208E-01 A4 = -9.77769E-03 -4.44538E-03 -2.11485E-03 -6.34894E-03 A6 = 2.27875E-04 6.61858E-04 2.99067E-04 1.97692E-04 A8 = -6.60987E-05 -8.81706E-05 -7.54614E-05 1.50555E-05 A10 = 1.17630E-06 2.68580E-06 4.12931E-06 3.86720E-07 A12 = - - - -1.10935E-07 surface 11 12 13 14 k = -7.48977E-01 -7.16293E-01 3.92532E-01 -1.31784E+01 A4 = 1.91972E-02 -5.00675E-04 4.73230E-03 2.74937E-02 A6 = -1.70871E-03 2.29042E-04 -7.30424E-04 -3.30679E-03 A8 = 4.13215E-04 9.92369E-05 1.37152E-05 1.90811E-04 A10 = -3.18254E-05 -8.63533E-06 1.57172E-07 -5.54063E-06 A12 = 8.89006E-07 2.26095E-07 -2.85367E-09 6.25708E-08 surface 15 16 k = -3.49373E+00 -3.18555E+00 A4 = -8.90319E-03 -5.58946E-03 A6 = 2.26039E-04 1.96829E-04 A8 = -1.18760E-06 4.98830E-06 A10 = 2.12060E-06 -7.34308E-07 A12 = -1.81523E-07 2.78324E-08 A14 = 5.27375E-09 -4.81897E-10 A16 = -5.18091E-11 3.22918E-12

[0278] In the twelfth embodiment, the equation of the curve of the aspherical surface is expressed in the form of the first embodiment. Furthermore, the definitions described in Table 12C are the same as those in the first embodiment, and will not be repeated here.

[0279] Table 12C, Polynomial Data f [millimeters] 6.95 |f6 / f7| 0.62 Fno 1.80 |f / R9|+|f / R10| 5.95 HFOV [degrees] 45.0 R6 / R7 0.18 FOV [degrees] 90.0 R10 / R11 -0.44 TL / ImgH 1.74 (R3 - R4) / (R3 + R4) 2.70 TL / f 1.76 ΣCT / ΣAT 4.58 SL / f 1.65 CT6 / CT2 0.76 TL / R1 0.35 (T12 + T23 + T56 + T67) / (T34 + T45) 0.28 TL / R3 0.87 T34 / T45 1.03 tan(HFOV) 1.00 [[ID=7']] T67 / T45 0.07 f / f1 + f / f2 0.89 V4 56.0 |f4 / f7| 1.09 Y7R2 / Y2R1 3.18 |f5 / f6| 1.48 - It should be noted that in the above translation, there is an error in the "ID=7'" in the original text. It should be "ID=70" in the translation. -

[0280] <Thirteenth Embodiment>

[0281] Please refer to Figure 25, which is a perspective view of an image capturing device according to the thirteenth embodiment of this disclosure. In this embodiment, the image capturing device 100 is a camera module. The image capturing device 100 includes an imaging lens 101, a driving device 102, an electronic image sensor 103, and an image stabilization module 104. The imaging lens 101 includes the image capturing optical system of the first embodiment described above, a lens barrel (not otherwise labeled) for carrying the image capturing optical system, and a support device (Holder Member, not otherwise labeled). The imaging lens 101 can also be replaced with the image capturing optical system of other embodiments described above, and this disclosure is not limited thereto. The image capturing device 100 uses the imaging lens 101 to focus light to generate an image, and cooperates with the driving device 102 to focus the image, finally imaging it on the electronic image sensor 103 and outputting it as image data.

[0282] The driving device 102 may have an auto-focus function, and its driving method can use a driving system such as a voice coil motor (VCM), microelectromechanical systems (MEMS), piezoelectric systems, and shape memory alloys. The driving device 102 enables the imaging lens 101 to achieve a better imaging position, allowing clear images to be captured of the subject at different object distances. In addition, the imaging device 100 is equipped with a high-sensitivity and low-noise electronic image sensor 103 (such as CMOS or CCD) located on the imaging surface of the imaging optical system, which can truly present the good imaging quality of the imaging optical system.

[0283] The image stabilization module 104 can be, for example, an accelerometer, a gyroscope, or a Hall effect sensor. The drive unit 102 can work in conjunction with the image stabilization module 104 to form an optical image stabilization (OIS) device. By adjusting the changes in different axes of the imaging lens 101, it can compensate for the blurry image caused by shaking during shooting, or use image compensation technology in the imaging software to provide electronic image stabilization (EIS) function, further improving the image quality of shooting in dynamic and low-light scenes.

[0284] <Fourteenth Embodiment>

[0285] Please refer to Figures 26 and 27, wherein Figure 26 shows a perspective view of one side of an electronic device according to the fourteenth embodiment of the present disclosure, and Figure 27 shows a perspective view of the other side of the electronic device of Figure 26.

[0286] In this embodiment, the electronic device 200 is a smartphone. The electronic device 200 includes an image capturing device 100, an image capturing device 100a, an image capturing device 100b, an image capturing device 100c, and a display module 201, as described in the thirteenth embodiment. As shown in FIG26, the image capturing devices 100, 100a, and 100b are all located on the same side of the electronic device 200 and are all single-focus. As shown in FIG27, the image capturing device 100c and the display module 201 are both located on the other side of the electronic device 200. The image capturing device 100c can serve as a front-facing camera to provide a selfie function, but this disclosure is not limited thereto. Furthermore, the image capturing devices 100a, 100b, and 100c can all include the image capturing optical system disclosed herein and can all have a structural configuration similar to that of the image capturing device 100. In detail, each of the image capturing devices 100a, 100b, and 100c may include an imaging lens, a driving device, an electronic photosensitive element, and an image stabilization module. The imaging lens of each of the image capturing devices 100a, 100b, and 100c may include, for example, an optical lens group (as disclosed in this imaging optical system), a lens barrel for supporting the optical lens group, and a support device.

[0287] Image capturing device 100 is a wide-angle image capturing device, image capturing device 100a is a telephoto image capturing device, image capturing device 100b is an ultra-wide-angle image capturing device, and image capturing device 100c is a wide-angle image capturing device. In this embodiment, image capturing devices 100, 100a, and 100b have different viewing angles, allowing the electronic device 200 to provide different magnifications to achieve optical zoom shooting effects. Furthermore, as shown in Figure 27, the opening of image capturing device 100c can be non-circular, and the lens barrel or lens inside image capturing device 100c can be cut at its outer diameter to have a chamfered edge to match the non-circular opening. This allows for a further reduction in the single-axis length of image capturing device 100c, which helps to reduce lens volume, increase the area ratio of display module 201 relative to electronic device 200, and reduce the thickness of electronic device 200, further achieving module miniaturization. The electronic device 200 described above includes multiple image capturing devices 100, 100a, 100b, and 100c, but the number and configuration of the image capturing devices are not intended to limit this disclosure.

[0288] <Fifteenth Embodiment>

[0289] Please refer to Figures 28 to 30, wherein Figure 28 shows a perspective view of one side of an electronic device according to the fifteenth embodiment of the present disclosure, Figure 29 shows a perspective view of the other side of the electronic device of Figure 28, and Figure 30 shows a system block diagram of the electronic device of Figure 28.

[0290] In this embodiment, the electronic device 300 is a smartphone. The electronic device 300 includes, according to the thirteenth embodiment, image capturing devices 100, 100d, 100e, 100f, and 100g, a flash module 301, a focus assist module 302, an image signal processor 303, a display module 304, and an image software processor 305. Image capturing devices 100 and 100d are both located on the same side of the electronic device 300. The focus assist module 302 may employ a laser ranging or a Time-of-Flight (ToF) module, but this disclosure is not limited to these methods. Image capturing devices 100e, 100f, 100g, and display module 304 are all located on the other side of electronic device 300, and display module 304 can serve as a user interface, allowing image capturing devices 100e, 100f, and 100g to function as front-facing cameras for selfies, but this disclosure is not limited thereto. Furthermore, image capturing devices 100d, 100e, 100f, and 100g can all include the image capturing optical system disclosed herein and can all have a structural configuration similar to that of image capturing device 100. Specifically, each of image capturing devices 100d, 100e, 100f, and 100g can include an imaging lens, a driving device, an electronic photosensitive element, and an image stabilization module. The imaging lenses of imaging devices 100d, 100e, 100f and 100g may each include, for example, an optical lens group of the imaging optical system disclosed herein, a lens barrel for carrying the optical lens group and a support device.

[0291] Image capturing device 100 is a wide-angle image capturing device, image capturing device 100d is an ultra-wide-angle image capturing device, image capturing device 100e is a wide-angle image capturing device, image capturing device 100f is an ultra-wide-angle image capturing device, and image capturing device 100g is a time-of-flight ranging image capturing device. In this embodiment, image capturing devices 100 and 100d have different viewing angles, allowing the electronic device 300 to provide different magnifications to achieve optical zoom shooting effects. Additionally, image capturing device 100g can acquire depth information of the image. The above-described electronic device 300 is exemplified by including multiple image capturing devices 100, 100d, 100e, 100f, and 100g, but the number and configuration of the image capturing devices are not intended to limit this disclosure.

[0292] When the user photographs the subject 306, the electronic device 300 uses the image capturing device 100 or image capturing device 100d to focus the light, activates the flash module 301 for supplemental lighting, and uses the subject distance information of the subject 306 provided by the focus assist module 302 for fast focusing. In addition, the image signal processor 303 performs image optimization processing to further improve the image quality produced by the imaging optical system. The focus assist module 302 can use an infrared or laser focus assist system to achieve fast focusing. Furthermore, the electronic device 300 can also use the image capturing devices 100e, 100f, or 100g for shooting. The display module 304 can use a touch screen, combined with the diverse functions of the image software processor 305 for image capturing and image processing (or can use a physical shooting button). The image processed by the image software processor 305 can be displayed on the display module 304.

[0293] <Sixteenth Embodiment>

[0294] Please refer to Figure 31, which is a perspective view of one side of an electronic device according to the sixteenth embodiment of this disclosure.

[0295] In this embodiment, the electronic device 400 is a smartphone. The electronic device 400 includes, according to the thirteenth embodiment, an image capturing device 100, an image capturing device 100h, an image capturing device 100i, a flash module 401, a focus assist module, an image signal processor, a display module, and an image software processor (not shown). The image capturing devices 100, 100h, and 100i are all located on the same side of the electronic device 400, while the display module is located on the other side. Furthermore, both the image capturing devices 100h and 100i may include the image capturing optical system disclosed herein and may have a similar structural configuration to the image capturing device 100, which will not be described in detail here.

[0296] Image capturing device 100 is a wide-angle image capturing device, image capturing device 100h is a telephoto image capturing device, and image capturing device 100i is an ultra-wide-angle image capturing device. In this embodiment, image capturing devices 100, 100h, and 100i have different viewing angles, allowing the electronic device 400 to provide different magnifications to achieve optical zoom shooting effects. Furthermore, image capturing device 100h is a telephoto image capturing device with an optical path deflection element configuration, so that the total length of image capturing device 100h is not limited by the thickness of the electronic device 400. The optical path deflection element configuration of image capturing device 100h can, for example, have a structure similar to Figures 36 to 38, which can be referred to in the descriptions corresponding to Figures 36 to 38 above, and will not be repeated here. The above-described electronic device 400 includes multiple image capturing devices 100, 100h, and 100i, but the number and configuration of the image capturing devices are not intended to limit this disclosure. When a user takes a picture of the subject, the electronic device 400 uses the image capturing device 100, image capturing device 100h or image capturing device 100i to focus the light and activate the flash module 401 to provide supplementary light. It also performs subsequent processing in a manner similar to the aforementioned embodiments, which will not be described in detail here.

[0297] <Seventeenth Embodiment>

[0298] Please refer to Figure 32, which is a perspective view of one side of an electronic device according to the seventeenth embodiment of this disclosure.

[0299] In this embodiment, the electronic device 500 is a smartphone. The electronic device 500 includes, according to the thirteenth embodiment, image capturing devices 100, 100j, 100k, 100m, 100n, 100p, 100q, 100r, and 100s, a flash module 501, a focus assist module, an image signal processor, a display module, and an image software processor (not shown). Image capturing devices 100, 100j, 100k, 100m, 100n, 100p, 100q, 100r, and 100s are all located on the same side of the electronic device 500, while the display module is located on the other side of the electronic device 500. Furthermore, the imaging devices 100j, 100k, 100m, 100n, 100p, 100q, 100r, and 100s can all include the imaging optical system disclosed herein and can all have a structural configuration similar to that of the imaging device 100, which will not be elaborated further here.

[0300] Image capturing device 100 is a wide-angle image capturing device, image capturing device 100j is a telephoto image capturing device, image capturing device 100k is a telephoto image capturing device, image capturing device 100m is a wide-angle image capturing device, image capturing device 100n is an ultra-wide-angle image capturing device, image capturing device 100p is an ultra-wide-angle image capturing device, image capturing device 100q is a telephoto image capturing device, image capturing device 100r is a telephoto image capturing device, and image capturing device 100s is a time-of-flight ranging image capturing device. In this embodiment, image capturing devices 100, 100j, 100k, 100m, 100n, 100p, 100q, and 100r have different viewing angles, allowing the electronic device 500 to provide different magnifications to achieve an optical zoom shooting effect. Furthermore, the image capturing devices 100j and 100k can be telescopic image capturing devices with optical path deflection elements. The optical path deflection element configuration of the image capturing devices 100j and 100k can, for example, have a structure similar to that shown in Figures 36 to 38, as described above with reference to the corresponding Figures 36 to 38, and will not be repeated here. Additionally, the image capturing device 100s can acquire depth information of the image. The above-described electronic device 500 is exemplified by including multiple image capturing devices 100, 100j, 100k, 100m, 100n, 100p, 100q, 100r, and 100s, but the number and configuration of the image capturing devices are not intended to limit this disclosure. When the user takes a picture of the subject, the electronic device 500 uses the image capturing devices 100, 100j, 100k, 100m, 100n, 100p, 100q, 100r, or 100s to focus the light and capture the image, activates the flash module 501 to provide supplementary lighting, and performs subsequent processing in a manner similar to the aforementioned embodiments, which will not be described in detail here.

[0301] <Eighteenth Embodiment>

[0302] Please refer to Figure 33, which is a perspective view of one side of an electronic device according to the eighteenth embodiment of this disclosure.

[0303] In this embodiment, the electronic device 600 is a small-sized camera, such as an action camera. The electronic device 600 includes a screen 601 and an image capturing device 602. The image capturing device 602 is electrically connected to the screen 601. The image capturing device 602 includes the image capturing optical system described in the first embodiment. The image capturing device 602 may be a wide-angle image capturing device. Similar to the image capturing device 100, the image capturing device 602 may further include a lens barrel, a support device, or a combination thereof. The electronic device 600 utilizes the image capturing device 602 to perform functions such as taking pictures. Preferably, the electronic device may further include a control unit, a display unit, a storage unit, a temporary storage unit (RAM), or a combination thereof.

[0304] The image capturing device disclosed herein is not limited to smartphones. It can also be applied to mobile focusing systems as needed, offering excellent aberration correction and good image quality. For example, the image capturing device can be used in various electronic devices such as 3D image capture, digital cameras, mobile devices, digital tablets, smart TVs, network surveillance equipment, dashcams, reversing cameras, multi-lens systems, recognition systems, motion-sensing game consoles, and wearable devices. The aforementioned electronic devices are merely illustrative examples of practical applications of this disclosure and do not limit the scope of application of the image capturing device disclosed herein.

[0305] Although this disclosure is based on the preferred embodiments described above, it is not intended to limit this disclosure. Anyone skilled in the art may make some modifications and refinements without departing from the spirit and scope of this disclosure. Therefore, the scope of patent protection of this disclosure shall be determined by the claims attached to this specification.

[0306] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 100, 100a, 100b, 100c, 100d, 100e, 100f, 1 00g, 100h, 100i, 100j, 100k, 100m, 100n, 100p, 100q, 100r, 100s, 602: imaging device 101: Imaging Lens 102: Drive unit 103: Electronic photosensitive element 104: Image Stabilization Module 200, 300, 400, 500, 600: Electronic devices 201, 304: Display module 301, 401, 501: Flash module 601: Screen 302: Focusing Assist Module 303: Image Signal Processor 305: Image Software Processor 306: Subject C: Critical point P: Inversion point OA1: First optical axis OA2: Second optical axis OA3: Third optical axis LF: Optical path switching element LF1: First optical path switching element LF2: Second optical path switching element LG: Lens Group ST: Aperture S1: Aperture E1: First lens E2: Second lens E3: Third Lens E4: Fourth Lens E5: Fifth Lens E6: Sixth Lens E7: Seventh Lens E8: Filter element IMG: Imaging Surface IS: Electronic photosensitive element ΣAT: The sum of the distances between all adjacent lenses on the optical axis in an imaging optical system. ΣCT: The total thickness of all lenses in the imaging optical system along the optical axis. CT2: Thickness of the second lens on the optical axis CT6: Thickness of the sixth lens on the optical axis f: Focal length of the imaging optical system f1: Focal length of the first lens f2: Focal length of the second lens f4: Focal length of the fourth lens f5: Focal length of the fifth lens f6: Focal length of the sixth lens f7: Focal length of the seventh lens Fno: Aperture value of the imaging optical system FOV: The maximum angle of view in an imaging optical system. HFOV: Half of the maximum field of view in an imaging optical system ImgH: Maximum imaging height of the imaging optical system R1: Radius of curvature of the object-side surface of the first lens R3: Radius of curvature of the object-side surface of the second lens R4: Radius of curvature of the image-side surface of the second lens R6: Radius of curvature of the image-side surface of the third lens R7: Radius of curvature of the object-side surface of the fourth lens R9: Radius of curvature of the object-side surface of the fifth lens R10: Radius of curvature of the image-side surface of the fifth lens R11: Radius of curvature of the object-side surface of the sixth lens SL: Distance from the aperture to the imaging plane along the optical axis T12: The distance between the first lens and the second lens on the optical axis T23: The distance between the second and third lenses on the optical axis T34: The distance between the third and fourth lenses on the optical axis T45: The distance between the fourth and fifth lenses on the optical axis T56: The distance between the fifth and sixth lenses on the optical axis T67: The distance between the sixth and seventh lenses on the optical axis TL: Distance along the optical axis from the object-side surface of the first lens to the imaging plane. V4: Abbe number of the fourth lens Y2R1: Maximum effective radius of the object-side surface of the second lens Y7R2: Maximum effective radius of the image-side surface of the seventh lens

Claims

1. An image-capturing optical system comprising seven lenses, the seven lenses being sequentially arranged from the object side to the image side along an optical path as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, and each of the seven lenses having an object-side surface facing the object side and an image-side surface facing the image side; wherein, The third lens has negative refractive power, the object-side surface of the fifth lens is concave near the optical axis, the sixth lens has positive refractive power, the seventh lens has negative refractive power, the object-side surface of the seventh lens is convex near the optical axis, the image-side surface of the seventh lens is concave near the optical axis, and the image-side surface of the seventh lens has at least one inflection point. Wherein, the distance on the optical axis from the object-side surface of the first lens to an imaging surface is TL, the radius of curvature of the object-side surface of the first lens is R1, the radius of curvature of the object-side surface of the second lens is R3, the optical axis spacing between the first lens and the second lens is T12, the optical axis spacing between the second lens and the third lens is T23, the optical axis spacing between the third lens and the fourth lens is T34, the optical axis spacing between the fourth lens and the fifth lens is T45, the optical axis spacing between the fifth lens and the sixth lens is T56, and the optical axis spacing between the sixth lens and the seventh lens is T67, which satisfies the following conditions: -2.50 < TL / R1 < 1.00; -2.50 < TL / R3 < 1.70; and 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.

70.

2. The imaging optical system as claimed in claim 1, wherein the fourth lens has positive refractive power and the fifth lens has negative refractive power.

3. The imaging optical system as described in claim 1, wherein the total thickness of all lenses in the imaging optical system on the optical axis is ΣCT, and the total distance between all adjacent lenses in the imaging optical system on the optical axis is ΣAT, which satisfies the following condition: 3.00 < ΣCT / ΣAT < 6.

50.

4. The imaging optical system as claimed in claim 1, wherein the focal length of the imaging optical system is f, the radius of curvature of the object-side surface of the fifth lens is R9, and the radius of curvature of the image-side surface of the fifth lens is R10, which satisfies the following condition: 4.00 < |f / R9|+|f / R10| < 8.

00.

5. The imaging optical system as claimed in claim 1, wherein the radius of curvature of the image-side surface of the fifth lens is R10 and the radius of curvature of the object-side surface of the sixth lens is R11, which satisfy the following condition: -0.70 < R10 / R11 < 0.

30.

6. The imaging optical system as claimed in claim 1 further includes an aperture, wherein the distance from the aperture to the imaging plane on the optical axis is SL, and the focal length of the imaging optical system is f, which satisfies the following condition: 1.40 < SL / f < 2.

00.

7. The imaging optical system as claimed in claim 1, wherein the distance between the fourth lens and the fifth lens on the optical axis is T45, the distance between the sixth lens and the seventh lens on the optical axis is T67, the focal length of the sixth lens is f6, and the focal length of the seventh lens is f7, which satisfies the following conditions: 0.00 < T67 / T45 < 0.60; and 0.20 < |f6 / f7| < 0.

90.

8. The imaging optical system as claimed in claim 1, wherein the focal length of the fifth lens is f5 and the focal length of the sixth lens is f6, satisfying the following condition: 0.70 < |f5 / f6| < 1.

80.

9. An image capturing device, comprising: an image capturing optical system as described in claim 1; and an electronic photosensitive element disposed on the imaging surface of the image capturing optical system.

10. An electronic device comprising: an image capturing device as described in claim 9.

11. An image-capturing optical system comprising seven lenses, the seven lenses being sequentially arranged from the object side to the image side along an optical path as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, and each of the seven lenses having an object-side surface facing the object side and an image-side surface facing the image side; wherein, The second lens has a convex surface near the optical axis on its image side, the third lens has negative refractive power, the fifth lens has negative refractive power, the fifth lens has a concave surface near the optical axis on its object side, the fifth lens has a convex surface near the optical axis on its image side, the seventh lens has negative refractive power, and the seventh lens has at least one inflection point on its image side. Wherein, the distance on the optical axis from the object-side surface of the first lens to an imaging plane is TL; the radius of curvature of the object-side surface of the first lens is R1; the radius of curvature of the object-side surface of the second lens is R3; the focal length of the sixth lens is f6; the focal length of the seventh lens is f7; the optical axis spacing between the first and second lenses is T12; the optical axis spacing between the second and third lenses is T23; the optical axis spacing between the third and fourth lenses is T34; the optical axis spacing between the fourth and fifth lenses is T45; the optical axis spacing between the fifth and sixth lenses is T56; and the optical axis spacing between the sixth and seventh lenses is T67, satisfying the following conditions: -2.20 < TL / R1 < 1.00; -2.50 < TL / R3 < 2.00; 0.00 < |f6 / f7| < 1.00; 0.00 < T67 / T45 < 0.80; and 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.

70.

12. The imaging optical system as claimed in claim 11, wherein the fourth lens has positive refractive power, the sixth lens has positive refractive power, the image-side surface of the seventh lens is concave near the optical axis, and the image-side surface of the seventh lens has at least one critical point off-axis; wherein, The distance from the object-side surface of the first lens to the imaging surface on the optical axis is TL, the focal length of the imaging optical system is f, and half of the maximum field of view in the imaging optical system is HFOV, which satisfies the following conditions: 1.60 < TL / f < 2.10; and 0.70 < tan(HFOV) < 1.

40.

13. The imaging optical system as claimed in claim 11, wherein the focal length of the fourth lens is f4 and the focal length of the seventh lens is f7, satisfying the following condition: 0.40 < |f4 / f7| < 1.

40.

14. The imaging optical system as claimed in claim 11, wherein the radius of curvature of the object-side surface of the second lens is R3 and the radius of curvature of the image-side surface of the second lens is R4, which satisfies the following condition: -0.50 < (R3-R4) / (R3+R4).

15. The imaging optical system as claimed in claim 11, wherein the distance from the object-side surface of the first lens to the imaging surface on the optical axis is TL, the radius of curvature of the object-side surface of the first lens is R1, and the radius of curvature of the object-side surface of the second lens is R3, which satisfy the following conditions: -2.10 < TL / R1 < 0.80; and -2.30 < TL / R3 < 1.

90.

16. The imaging optical system as claimed in claim 11, wherein the thickness of the second lens on the optical axis is CT2 and the thickness of the sixth lens on the optical axis is CT6, which satisfy the following condition: 0.30 < CT6 / CT2 < 1.

25.

17. The imaging optical system as claimed in claim 11, wherein the optical axis spacing between the first lens and the second lens is T12, the optical axis spacing between the second lens and the third lens is T23, the optical axis spacing between the third lens and the fourth lens is T34, the optical axis spacing between the fourth lens and the fifth lens is T45, the optical axis spacing between the fifth lens and the sixth lens is T56, and the optical axis spacing between the sixth lens and the seventh lens is T67, which satisfies the following condition: 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.

60.

18. The imaging optical system as claimed in claim 11, wherein the Abbe number of the fourth lens is V4, which satisfies the following condition: 35.0 < V4 < 75.

0.

19. An image-capturing optical system comprising seven lenses, the seven lenses being sequentially arranged from the object side to the image side along an optical path as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, and each of the seven lenses having an object-side surface facing the object side and an image-side surface facing the image side; wherein, The object-side surface of the first lens is concave near the optical axis, the object-side surface of the second lens is concave near the optical axis, the third lens has negative refractive power, the object-side surface of the fifth lens is concave near the optical axis, the image-side surface of the fifth lens is convex near the optical axis, the sixth lens has positive refractive power, and the image-side surface of the seventh lens has at least one inflection point. Wherein, the distance on the optical axis from the object-side surface of the first lens to an imaging surface is TL, the radius of curvature of the object-side surface of the first lens is R1, the radius of curvature of the object-side surface of the second lens is R3, the optical axis spacing between the first lens and the second lens is T12, the optical axis spacing between the second lens and the third lens is T23, the optical axis spacing between the third lens and the fourth lens is T34, the optical axis spacing between the fourth lens and the fifth lens is T45, the optical axis spacing between the fifth lens and the sixth lens is T56, and the optical axis spacing between the sixth lens and the seventh lens is T67, which satisfies the following conditions: TL / R1 < 0.00; TL / R3 < 0.00; and 0.00 < (T12+T23+T56+T67) / (T34+T45) < 0.

70.

20. The imaging optical system as claimed in claim 19, wherein the fourth lens has positive refractive power, the fifth lens has negative refractive power, the sixth lens has positive refractive power, the seventh lens has negative refractive power, and the image-side surface of the seventh lens is concave near the optical axis.

21. The imaging optical system as claimed in claim 19, wherein the image-side surface of the first lens is convex near the optical axis, the image-side surface of the second lens is convex near the optical axis, the image-side surface of the third lens is concave near the optical axis, the image-side surface of the fourth lens is convex near the optical axis, and the image-side surface of the sixth lens is convex near the optical axis.

22. The imaging optical system as claimed in claim 19, wherein the distance from the object-side surface of the first lens to the imaging surface on the optical axis is TL, and the maximum imaging height of the imaging optical system is ImgH, which satisfies the following condition: 1.50 < TL / ImgH < 2.

10.

23. The imaging optical system as claimed in claim 19, wherein the focal length of the imaging optical system is f, the focal length of the first lens is f1, and the focal length of the second lens is f2, which satisfies the following condition: 0.50 < f / f1 + f / f2 < 3.

00.

24. The imaging optical system as claimed in claim 19, wherein the radius of curvature of the image-side surface of the third lens is R6 and the radius of curvature of the object-side surface of the fourth lens is R7, which satisfy the following condition: -0.40 < R6 / R7 < 0.

55.

25. The imaging optical system as claimed in claim 19, wherein the distance between the third lens and the fourth lens on the optical axis is T34, and the distance between the fourth lens and the fifth lens on the optical axis is T45, which satisfies the following condition: 0.50 < T34 / T45 < 1.

80.

26. The imaging optical system as claimed in claim 19, wherein the maximum effective radius of the object-side surface of the second lens is Y2R1 and the maximum effective radius of the image-side surface of the seventh lens is Y7R2, which satisfy the following condition: 2.20 < Y7R2 / Y2R1 < 5.

00.

27. The imaging optical system as described in claim 19, wherein the distance on the optical axis from the object-side surface of the first lens to the imaging plane is TL, the radius of curvature of the object-side surface of the first lens is R1, the radius of curvature of the object-side surface of the second lens is R3, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the optical axis spacing between the first and second lenses is T12, the optical axis spacing between the second and third lenses is T23, the optical axis spacing between the third and fourth lenses is T34, the optical axis spacing between the fourth and fifth lenses is T45, the optical axis spacing between the fifth and sixth lenses is T56, and the optical axis spacing between the sixth and seventh lenses is T67, satisfying the following conditions: -1.95 ≤ TL / R1 < 0.00; -2.14 ≤ TL / R3 < 0.00; 0.36 ≤ |f6 / f7| ≤ 0.83; 0.13 ≤ (T12+T23+T56+T67) / (T34+T45) ≤ 0.49; and 0.06 ≤ T67 / T45 ≤ 0.42.

Images