Optical system and optical lens

Abstract

The utility model discloses an optical system and an optical lens. The optical system sequentially comprises a first lens, a second lens, a super lens, a third lens, a fourth lens, a fifth lens and a sixth lens from an object side to an image side along an optical axis. The focal power of the first lens and the super lens is positive, and the surface, close to the object side, of the first lens protrudes towards the object side; the focal power of the fourth lens is positive; the focal power of the fifth lens is negative, the surface, close to the object side, of the fifth lens protrudes towards the image side, and the surface, close to the image side, of the fifth lens protrudes towards the object side; the focal power of the sixth lens is positive, the surface, close to the object side, of the sixth lens protrudes towards the object side, and the surface, close to the image side, of the sixth lens protrudes towards the image side. In the application, the optical system has a larger depth of field and can obtain more details, and compared with a zoom optical system of the same specification in the prior art, the zoom optical system has the advantages of simple structure, larger aperture, smaller volume, lighter weight and lower cost.

Description

Technical Field

[0001] The present application relates to the field of optical systems, and in particular to an optical system and an optical lens. Background Art

[0002] Compared with short-focus lenses, telephoto lenses have a higher magnification when observing the same object, so more detailed information can be obtained. According to optical principles, the depth of field of an optical system is inversely proportional to the focal length. When the aperture number is constant, the larger the focal length, the smaller the depth of field. Therefore, telephoto lenses have a smaller depth of field than short-focus lenses, that is, a smaller observation range. In some fields, such as the field of camera drones, the optical system may need to meet the requirements of having a large depth of field and being able to obtain more details at the same time, that is, it can simultaneously meet the requirements of clear imaging at close and long distances, and can obtain more detailed information when observing small or distant targets.

[0003] In order to obtain a large depth of field and more details at the same time, a common practice in the prior art is to use a zoom optical system, which can adjust the internal lens structure according to different working distances so that clear images can be obtained at different positions. However, the zoom optical system has the problems of complex internal structure design, large size and weight, and high cost. Utility Model Content

[0004] In response to the above technical problems, the embodiments of the present application provide an optical system and an optical lens, aiming to provide an optical system with a simple structure, small size and weight, low cost, large depth of field, and the ability to obtain more details.

[0005] According to one aspect of an embodiment of the present application, an optical system is disclosed, wherein the optical system includes, in order from the object side to the image side along the optical axis: a first lens, a second lens, a super lens, a third lens, a fourth lens, a fifth lens, and a sixth lens;

[0006] The optical focal power of the first lens is positive, and the surface of the first lens close to the object side is convex toward the object side; the optical focal power of the super lens is positive; the optical focal power of the fourth lens is positive; the optical focal power of the fifth lens is negative, and the surface of the fifth lens close to the object side is convex toward the image side, and the surface of the fifth lens close to the image side is convex toward the object side; the optical focal power of the sixth lens is positive, and the surface of the sixth lens close to the object side is convex toward the object side, and the surface of the sixth lens close to the image side is convex toward the image side.

[0007] In some embodiments, the optical system satisfies:

[0008]

[0009] Wherein, f1 is the focal length of the first lens, n6 is the refractive index of the sixth lens, and RS 11 is the radius of curvature of the surface of the first lens close to the object side, and the RS 62 is the radius of curvature of the surface of the sixth lens close to the image side.

[0010] In some embodiments, the optical system satisfies:

[0011]

[0012] Wherein, the FNO is the aperture number of the optical system, is the maximum phase difference of the metalens, and the R M is the effective radius of the super lens, the DS6 is the effective diameter of the sixth lens, and the EPD is the entrance pupil diameter of the optical system.

[0013] In some embodiments, the optical system satisfies:

[0014]

[0015] Wherein, the first lens, the second lens, the super lens and the third lens form a first lens group, the f A is the effective focal length of the first lens group; the fifth lens and the sixth lens form a second lens group, and the f B is the effective focal length of the second lens group.

[0016] In some embodiments, the optical system satisfies:

[0017]

[0018] Among them, the θ i is the maximum incident angle of the marginal ray of the maximum field of view on the surface of the fourth lens close to the object side, the θ r It is the maximum exit angle of the marginal light with the maximum field of view on the surface of the fifth lens close to the image side.

[0019] In some embodiments, the optical system satisfies:

[0020]

[0021] Among them, the CT4 is the center thickness of the fourth lens, and the ET4 is the edge thickness of the fourth lens; the ET5 is the edge thickness of the fifth lens, and the CT5 is the center thickness of the fifth lens.

[0022] In some embodiments, the optical system satisfies:

[0023] Wherein, the TTL is the total optical length of the optical system, and f is the effective focal length of the optical system.

[0024] In some embodiments, the optical system satisfies:

[0025] 0.9mm≤ΔBFL≤0.94mm;

[0026] The ΔBFL is the difference between the optical back focal length of the optical system at the shortest working distance and the optical back focal length of the optical system at the farthest working distance.

[0027] In some embodiments, the optical system satisfies:

[0028]

[0029] Wherein, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f M is the focal length of the super lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens; f5 is the focal length of the fifth lens; f6 is the focal length of the sixth lens, and f is the effective focal length of the optical system.

[0030] In some embodiments, the optical system satisfies:

[0031] 1.45≤nd1≤1.6,65≤vd1≤82;

[0032] 1.50≤nd2≤1.93,30≤vd2≤60;

[0033] 1.44≤nd M ≤1.49,65≤vd M ≤70;

[0034] 1.46≤nd3≤1.7,21≤vd3≤80;

[0035] 1.6≤nd4≤1.75, 21≤vd4≤30;

[0036] 1.55≤nd5≤1.85,38≤vd5≤70;

[0037] 1.46≤nd6≤1.55,69≤vd6≤85;

[0038] Wherein, nd1 is the refractive index of the first lens, vd1 is the Abbe number of the first lens; nd2 is the refractive index of the second lens, vd2 is the Abbe number of the second lens; Mis the refractive index of the metalens, and vd M is the Abbe number of the super lens; the nd3 is the refractive index of the third lens, and the vd3 is the Abbe number of the third lens; the nd4 is the refractive index of the fourth lens, and the vd4 is the Abbe number of the fourth lens; the nd5 is the refractive index of the fifth lens, and the vd5 is the Abbe number of the fifth lens; the nd6 is the refractive index of the sixth lens, and the vd6 is the Abbe number of the sixth lens.

[0039] In some embodiments, the optical system satisfies:

[0040] 0.06mm≤L 12 ≤0.3mm;

[0041] 0.3mm≤L 2M ≤0.45mm;

[0042] 0.05mm≤L M3 ≤3.3mm;

[0043] 7.8mm≤L 34 ≤10mm;

[0044] 0.2mm≤L 45 ≤0.9mm;

[0045] 11.2mm≤L 56 ≤13.1mm;

[0046] Among them, the L 12 is the distance of the air gap between the first lens and the second lens on the optical axis; the L 2M is the distance of the air gap between the second lens and the super lens on the optical axis; the L M3 is the distance of the air gap between the super lens and the third lens on the optical axis; 34 is the distance of the air space between the third lens and the fourth lens on the optical axis; 45 is the distance of the air space between the fourth lens and the fifth lens on the optical axis; 56 is the distance of the air space between the fifth lens and the sixth lens on the optical axis.

[0047] In some embodiments, the optical system further includes an aperture stop, and the aperture stop is disposed between any two adjacent lenses; or, the aperture stop is disposed on a side of the first lens away from the image side.

[0048] A second aspect of an embodiment of the present application provides an optical lens, comprising: an image sensor and an optical system as described in any one of the above items; the image sensor is arranged on an image plane of the optical system.

[0049] The optical system provided by the present application includes: a first lens, a second lens, a super lens, a third lens, a fourth lens, a fifth lens and a sixth lens in sequence from the object side to the image side along the optical axis. The optical power of the first lens is positive, and the surface of the first lens close to the object side is convex to the object side; the optical power of the super lens is positive; the optical power of the fourth lens is positive; the optical power of the fifth lens is negative, and the surface of the fifth lens close to the object side is convex to the image side, and the surface of the fifth lens close to the image side is convex to the object side; the optical power of the sixth lens is positive, and the surface of the sixth lens close to the object side is convex to the object side, and the surface of the sixth lens close to the image side is convex to the image side. In the present application, the optical system can achieve clear imaging of both near and far views, so that the optical system has a large depth of field. In addition, the optical system provided by the present application has a long focal length, which can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. Compared with the zoom optical system of the same specification in the prior art, the optical system provided by the present application does not have a mechanical structure for zooming, and has the advantages of simple structure, large aperture, small size, light weight and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

[0051] Figure 1 A schematic diagram of the architecture layout of an optical system in an embodiment of the present application is shown.

[0052] Figure 2 shows a phase diagram of a metalens in one embodiment of the present application;

[0053] Figure 3 A field curvature diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0054] Figure 4 A distortion diagram of the optical system at a working distance of infinity in one embodiment of the present application is shown.

[0055] Figure 5 A chromatic aberration diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0056] Figure 6 A relative illumination diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0057] Figure 7The MTF field of view curve of the optical system at 20° C. when the working distance is infinity in one embodiment of the present application is shown.

[0058] Figure 8 The MTF field curve of the optical system in one embodiment of the present application is shown at -10°C when the working distance is infinity.

[0059] Fig. 9 The MTF field curve of the optical system at 60° C. when the working distance is infinity in one embodiment of the present application is shown.

[0060] Fig.10 A field curvature diagram of the optical system at a working distance of 3 meters in one embodiment of the present application is shown.

[0061] Fig.11 The MTF field of view curve of the optical system in one embodiment of the present application is shown at a working distance of 3 meters at 20°C.

[0062] Fig.12 A schematic diagram of the architecture layout of an optical system in an embodiment of the present application is shown.

[0063] Fig.13 shows a phase diagram of a metalens in one embodiment of the present application;

[0064] Fig.14 A field curvature diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0065] Fig.15 A distortion diagram of the optical system at a working distance of infinity in one embodiment of the present application is shown.

[0066] Fig.16 A chromatic aberration diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0067] Fig.17 A relative illumination diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0068] Fig.18 The MTF field of view curve of the optical system at 20° C. when the working distance is infinity in one embodiment of the present application is shown.

[0069] Fig.19 The MTF field curve of the optical system in one embodiment of the present application is shown at -10°C when the working distance is infinity.

[0070] Fig. 20 The MTF field curve of the optical system at 60° C. when the working distance is infinity in one embodiment of the present application is shown.

[0071] Fig.21 A field curvature diagram of the optical system at a working distance of 3 meters in one embodiment of the present application is shown.

[0072] Fig. 22 The MTF field of view curve of the optical system in one embodiment of the present application is shown at a working distance of 3 meters at 20°C.

[0073] Fig.23 A schematic diagram of the architecture layout of an optical system in an embodiment of the present application is shown.

[0074] Fig.24 shows a phase diagram of a metalens in one embodiment of the present application;

[0075] Fig.25 A field curvature diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0076] Fig.26 A distortion diagram of the optical system at a working distance of infinity in one embodiment of the present application is shown.

[0077] Fig. 27 A chromatic aberration diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0078] Fig.28 A relative illumination diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0079] Fig.29 The MTF field of view curve of the optical system at 20° C. when the working distance is infinity in one embodiment of the present application is shown.

[0080] Fig.30 The MTF field curve of the optical system in one embodiment of the present application is shown at -10°C when the working distance is infinity.

[0081] Fig.31 The MTF field curve of the optical system at 60° C. when the working distance is infinity in one embodiment of the present application is shown.

[0082] Fig.32 A field curvature diagram of the optical system at a working distance of 3 meters in one embodiment of the present application is shown.

[0083] Fig.33 The MTF field of view curve of the optical system in one embodiment of the present application is shown at a working distance of 3 meters at 20°C.

[0084] Fig.34 A schematic diagram of the architecture layout of an optical system in an embodiment of the present application is shown.

[0085] Fig.35 shows a phase diagram of a metalens in one embodiment of the present application;

[0086] Fig.36 A field curvature diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0087] Fig.37 A distortion diagram of the optical system at a working distance of infinity in one embodiment of the present application is shown.

[0088] Fig.38 A chromatic aberration diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0089] Fig.39 A relative illumination diagram of an optical system at a working distance of infinity in one embodiment of the present application is shown.

[0090] Fig.40 The MTF field of view curve of the optical system at 20° C. when the working distance is infinity in one embodiment of the present application is shown.

[0091] Fig.41 The MTF field curve of the optical system in one embodiment of the present application is shown at -10°C when the working distance is infinity.

[0092] Fig.42 The MTF field curve of the optical system at 60° C. when the working distance is infinity in one embodiment of the present application is shown.

[0093] Fig.43 A field curvature diagram of the optical system at a working distance of 3 meters in one embodiment of the present application is shown.

[0094] Fig.44 The MTF field of view curve of the optical system in one embodiment of the present application is shown at a working distance of 3 meters at 20°C.

[0095] Reference numerals

[0096] 100. Optical system; 1. First lens; 2. Second lens; 3. Super lens; 31. Substrate; 32. Micro-nano structure; 4. Third lens; 5. Fourth lens; 6. Fifth lens; 7. Sixth lens; 8. Aperture; 9. Filter; A. Object plane; B. Image plane; S. Optical axis. DETAILED DESCRIPTION

[0097] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of the present application will be more comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The accompanying drawings are only schematic illustrations of the present application and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0098] In addition, the described features, structures or characteristics may be combined in one or more example embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the example embodiments of the present application. However, those skilled in the art will appreciate that the technical solution of the present application may be practiced while omitting one or more of the specific details, or other modules, components, etc. may be adopted. In other cases, known structures, methods, implementations or operations are not shown or described in detail to avoid obscuring the present application and making the various aspects of the present application obscure.

[0099] See also Figure 1 , Figure 1 FIG. 1 shows a schematic diagram of the structure layout of an optical system 100 in an embodiment of the present application, wherein the optical axis S is the center line of the light beam. Figure 1 In the figure, the object to be measured is located on the left side of the leftmost lens, that is, the object side is located on the left side of the leftmost lens, and the object plane A is located on the object side. The image formed by the optical system 100 is located on the right side of the rightmost lens, that is, the image side is located on the right side of the rightmost lens, and the image plane B is located on the image side. Therefore, the direction from the object plane A to the image plane B along the optical axis S is consistent with the direction from the object side to the image side along the optical axis S.

[0100] The optical system 100 includes a first lens 1, a second lens 2, a super lens 3, a third lens 4, a fourth lens 5, a fifth lens 6 and a sixth lens 7. The first lens 1, the second lens 2, the super lens 3, the third lens 4, the fourth lens 5, the fifth lens 6 and the sixth lens 7 are arranged in sequence from the object side to the image side.

[0101] The optical power of the first lens 1 is positive, the surface of the first lens 1 close to the object side is convex toward the object side, and the surface of the first lens 1 close to the image side is convex toward the object side or the image side.

[0102] The optical power of the second lens 2 can be positive or negative, that is, in some embodiments, the optical power of the second lens 2 is positive, and in other embodiments, the optical power of the second lens 2 is negative.

[0103] The optical power of the superlens 3 is positive. The superlens 3 includes a substrate 31 and a micro-nano structure 32, and the micro-nano structure 32 is arranged on the surface of the substrate 31 close to the object side and / or the surface of the substrate 31 close to the image side. According to the phase modulation method adopted, the corresponding phase modulation formula can be adaptively used to configure the various parameters of the micro-nano structure 32, so that the superlens 3 can achieve the expected optical performance.

[0104] The refractive power of the third lens 4 can be positive or negative, that is, in some embodiments, the refractive power of the third lens 4 is positive, and in other embodiments, the refractive power of the third lens 4 is negative.

[0105] The refractive power of the fourth lens 5 is positive.

[0106] The refractive power of the fifth lens 6 is negative, the surface of the fifth lens 6 close to the object side is convex toward the image side, and the surface of the fifth lens 6 close to the image side is convex toward the object side.

[0107] The refractive power of the sixth lens 7 is positive. The surface of the sixth lens 7 close to the object side is convex toward the object side, and the surface of the sixth lens 7 close to the image side is convex toward the image side.

[0108] In the present application, the optical system 100 can achieve clear imaging of both near and far views, so that the optical system 100 has a large depth of field. In addition, the optical system 100 provided in the present application has a long focal length, which can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. Compared with the zoom optical system of the same specification in the prior art, the optical system 100 provided in the present application does not have a mechanical structure for zooming, and has the advantages of simple structure, large aperture, small size, light weight and low cost.

[0109] See also Figure 1 , Fig.12 , Fig.23 In some embodiments, the surface of the first lens 1 close to the image side is convex toward the image side, that is, the first lens 1 is a biconvex lens.

[0110] See also Fig.34 In some embodiments, the surface of the first lens 1 close to the image side is convex toward the object side, that is, the first lens 1 is a meniscus lens.

[0111] In some embodiments, the optical system 100 can form clear images from 3 meters to infinity, that is, the focusing range of the optical system 100 is from 3 meters to infinity.

[0112] In some embodiments, the micro-nano structure 32 is disposed on a surface of the substrate 31 close to the object side.

[0113] In some embodiments, the micro-nano structure 32 is disposed on a surface of the substrate 31 close to the image side.

[0114] In some embodiments, the surface of the substrate 31 close to the object side and the surface of the substrate 31 close to the image side are both provided with micro-nano structures 32, so that the superlens 3 has a higher degree of design freedom.

[0115] In some embodiments, the micro-nanostructure 32 is a positive micro-nanostructure.

[0116] In some embodiments, the micro-nano structure 32 is a negative micro-nano structure.

[0117] In some embodiments, the micro-nano structure 32 is provided with a layer to make the processing technology of the superlens 3 compatible with the existing semiconductor processing technology, which can facilitate the processing and manufacturing of the superlens 3.

[0118] In some embodiments, the micro-nano structure 32 has two or more layers, so that the superlens 3 has a larger and expected optical focal length.

[0119] For the superlens 3, the position of the micro-nano structure 32, the positive and negative of the micro-nano structure 32, and the number of layers of the micro-nano structure 32 can be freely combined as long as the superlens 3 has the expected performance.

[0120] In some embodiments, the specific structure of the superlens 3 is as follows: the micro-nano structure 32 is provided on the surface of the substrate 31 close to the object side, and the micro-nano structure 32 is provided with only one layer, so that the superlens 3 has good processability and also has an optical focal length that meets the expected requirements. It should be noted that this is only used for illustration and should not be understood as a limitation on the specific structure of the superlens 3.

[0121] In some embodiments, the phase distribution of the superlens 3 satisfies the following formula:

[0122]

[0123] Where r is the distance from the center of the superlens to any micro-nanostructure, λ is the central wavelength of the working band of the superlens, is the phase constant, (x, y) is the two-dimensional coordinate of the surface of the metalens, and ai and bi are real coefficients. M is the focal length of the metalens,

[0124] In some embodiments, the first lens 1 , the second lens 2 , the third lens 4 , the fourth lens 5 , the fifth lens 6 and the sixth lens 7 are all spherical lenses, so that the cost of the optical system 100 can be further reduced.

[0125] In some embodiments, at least one of the second lens 2 , the third lens 4 , and the fourth lens 5 is an aspherical lens, so that the imaging quality of the optical system 100 can be further improved.

[0126] In some embodiments, the first lens 1, the second lens 2, the third lens 4, the fourth lens 5, the fifth lens 6 and the sixth lens 7 are all made of glass, so that the optical system 100 has a good athermal effect, and when the ambient temperature changes within a certain range, the optical system 100 can still maintain good imaging quality, so that the optical system 100 has good environmental adaptability.

[0127] Specifically, in some embodiments, when the optical system 100 is in the range of -10°C to 60°C, the MTF (Modulation Transfer Function, MTF for short) value of the optical system 100 is less affected by temperature, that is, the optical system 100 has a good athermal effect in the range of -10°C to 60°C.

[0128] In some embodiments, the optical system 100 satisfies Condition 1: Wherein, f1 is the focal length of the first lens 1, n6 is the refractive index of the sixth lens 7, RS 11 is the radius of curvature of the surface of the first lens 1 close to the object side, RS 62 f1, RS is the curvature radius of the surface of the sixth lens 7 close to the image side. 11 , RS 62 have the same dimension, which is a unit of length, such as millimeter.

[0129] Conditional formula 1 is used to ensure that the focal power of the optical system 100 is reasonably distributed, and to ensure a smooth transition between the incident light and the outgoing light, so that the aberrations borne by each lens are relatively dispersed, which is conducive to the complementarity of the aberrations between the lenses, thereby reducing the aberrations of the optical system 100. At the same time, conditional formula 1 can also avoid that a certain lens in the optical system 100 needs to provide a large aberration contribution. If a certain lens needs to provide a large aberration contribution, the optical system 100 will be more sensitive to tolerances, which is not conducive to the assembly of the optical system 100. That is, conditional formula 1 can also ensure that the optical system 100 has a high tolerance for tolerances.

[0130] In some embodiments, the optical system 100 satisfies Conditional Formula 2:

[0131] Here, FNO is the aperture number of the optical system 100 , that is, the F number of the optical system 100 . is the maximum phase difference of superlens 3, The unit of R is rad. M is the effective radius of the metalens 3, specifically, R M is the radius of the maximum light transmission area of ​​the superlens 3, R MThe dimension is a length unit, such as millimeter. DS6 is the effective diameter of the sixth lens 7, specifically, DS6 is the diameter of the maximum light transmission area of ​​the sixth lens 7. EPD (Backfocal length, abbreviated as BFL) is the entrance pupil diameter of the optical system 100. DS6 and EPD have the same dimension, both of which are length units, such as millimeter.

[0132] The conditional expression 2 can effectively improve the light converging ability of the optical system 100, and can control the distance of light of different wavelengths in the direction perpendicular to the optical axis S to be less than the radius of the Airy disk, thereby reducing the chromatic aberration of the optical system 100. At the same time, the conditional expression 2 can also constrain the difference between the apertures of the first lens 1 and the sixth lens 7 not to be too large, thereby maintaining the balance of the optical system 100 from the object plane A to the image plane B.

[0133] In some embodiments, the optical system 100 satisfies Condition 3: Among them, the first lens 1, the second lens 2, the super lens 3 and the third lens 4 form a first lens group 1, f A is the effective focal length of the first lens group. The fifth lens 6 and the sixth lens 7 form the second lens group 2, f B is the effective focal length of the second lens group. A 、f B have the same dimension, which is a unit of length, such as millimeter.

[0134] Conditional formula three is used to reasonably distribute the optical power of the first lens group and the second lens group, so that the optical system 100 can effectively adjust the incident light during close-up and long-distance shooting, so that the incident light during close-up and long-distance shooting still maintains a high degree of convergence at different positions of the image plane B, so that the optical system 100 still has a high imaging quality when adjusting the optical back focal length.

[0135] In some embodiments, the optical system 100 satisfies Condition 4: Among them, θ i is the maximum incident angle of the marginal ray of the maximum field of view on the surface of the fourth lens 5 close to the object side. Specifically, θ i θ is the angle between the edge ray of the maximum field of view and the optical axis S on the surface of the fourth lens 5 close to the object side. r is the maximum angle of incidence of the marginal ray of the maximum field of view on the surface of the fifth lens 6 close to the image side. Specifically, θ r It is the angle between the edge ray of the maximum field of view and the optical axis S on the surface of the fifth lens 6 close to the image side.

[0136] Conditional formula 4 is used to eliminate astigmatism and field curvature generated by the edge field of view and reduce distortion, thereby improving the consistency of imaging clarity on the image plane B, which is beneficial to improving the imaging quality of the optical system 100.

[0137] In some embodiments, the optical system 100 satisfies Condition 5: Wherein, CT4 is the center thickness of the fourth lens 5, that is, CT4 is the thickness of the fourth lens 5 on the optical axis S. ET4 is the edge thickness of the fourth lens 5. ET5 is the edge thickness of the fifth lens 6, and CT5 is the center thickness of the fifth lens 6, that is, CT5 is the thickness of the fifth lens 6 on the optical axis S.

[0138] Conditional formula 5 is used to ensure that the positive spherical aberration and the negative spherical aberration generated by the lens in the optical system 100 are complementary, so that the positive spherical aberration and the negative spherical aberration of the optical system 100 can offset each other, which can effectively improve the convergence of the light spot and make the imaging effect of the optical system 100 sharper. CT4, ET4, ET5 and CT5 have the same dimension, which is a length unit, such as millimeter.

[0139] In some embodiments, the optical system 100 satisfies Conditional Formula 6: Wherein, TTL (Total Track Length, TTL for short) is the total optical length of the optical system 100. In the present application, the total optical length is the distance between the surface of the first lens 1 close to the object side and the image plane B on the optical axis S. f is the effective focal length of the optical system 100. TTL and f have the same dimension, both of which are length units, such as millimeters.

[0140] Conditional Expression 6 can ensure that the optical system 100 has a high definition while reducing the total optical length of the optical system 100 , thereby reducing the weight and volume of the optical system 100 , so that the optical system 100 can be miniaturized.

[0141] In some embodiments, the optical system 100 satisfies conditional formula 7: 0.9 mm ≤ ΔBFL ≤ 0.94 mm, where ΔBFL is the difference between the optical back focal length BFL1 of the optical system 100 at the closest working distance and the optical back focal length BFL2 of the optical system 100 at the farthest working distance. Specifically, in the present application, the focusing range of the optical system 100 is from 3 meters to infinity to meet the needs of shooting close-up and distant scenes. Therefore, BFL1 is the optical back focal length of the optical system 100 when the working distance is 3 meters; BFL2 is the optical back focal length of the optical system 100 when the working distance is infinity.

[0142] Conditional formula seven can ensure that the optical system 100 can meet the focus of near and far views, and at the same time can ensure that the change of the optical back focal length is within a certain range, which can make the structure of the optical system 100 more stable, can effectively reduce mechanical wear, and can increase the service life of the optical system 100.

[0143] In some embodiments, the optical system 100 satisfies Conditional Equation 8:

[0144]

[0145] Where, f1 is the focal length of the first lens 1, f2 is the focal length of the second lens 2, and f M is the focal length of the metalens 3, f3 is the focal length of the third lens 4, f4 is the focal length of the fourth lens 5; f5 is the focal length of the fifth lens 6; f6 is the focal length of the sixth lens 7, and f is the effective focal length of the optical system 100. M , f3, f4, f5, f6 and f have the same dimension, which is length unit, such as millimeter.

[0146] Conditional formula eight is used to ensure that each lens in the optical system 100 has a reasonable optical power, so as to achieve a reasonable distribution of the optical power of the optical system 100.

[0147] In some embodiments, the optical system 100 satisfies Conditional Formula 9:

[0148] 1.45≤nd1≤1.6,65≤vd1≤82;

[0149] 1.50≤nd2≤1.93,30≤vd2≤60;

[0150] 1.44≤nd M ≤1.49,65≤vd M ≤70;

[0151] 1.46≤nd3≤1.7,21≤vd3≤80;

[0152] 1.6≤nd4≤1.75, 21≤vd4≤30;

[0153] 1.55≤nd5≤1.85,38≤vd5≤70;

[0154] 1.46≤nd6≤1.55,69≤vd6≤85;

[0155] Wherein, nd1 is the refractive index of the first lens 1, and vd1 is the Abbe number of the first lens 1. nd2 is the refractive index of the second lens 2, and vd2 is the Abbe number of the second lens 2. M is the refractive index of the superlens 3, vd M is the Abbe number of the super lens 3. nd3 is the refractive index of the third lens 4, and vd3 is the Abbe number of the third lens 4. nd4 is the refractive index of the fourth lens 5, and vd4 is the Abbe number of the fourth lens 5. nd5 is the refractive index of the fifth lens 6, and vd5 is the Abbe number of the fifth lens 6. nd6 is the refractive index of the sixth lens 7, and vd6 is the Abbe number of the sixth lens 7. The refractive index and Abbe number of each lens in conditional formula 9 are relative to d light.

[0156] Conditional formula 9 controls the refractive index and Abbe number of each lens in the optical system 100 to be within a reasonable range, which can achieve reasonable matching of lenses, reduce aberrations by offsetting positive and negative aberrations, and improve imaging quality. Constraining the Abbe number can effectively reduce the chromatic aberration generated by the optical system 100, so that the optical system 100 has a higher degree of color restoration of objects.

[0157] In some embodiments, the optical system 100 satisfies Conditional Equation 10:

[0158] 0.06mm≤L 12 ≤0.3mm;

[0159] 0.3mm≤L 2M ≤0.45mm;

[0160] 0.05mm≤L M3 ≤3.3mm;

[0161] 7.8mm≤L 34 ≤10mm;

[0162] 0.2mm≤L 45 ≤0.9mm;

[0163] 11.2mm≤L 56 ≤13.1mm;

[0164] Among them, L 12 L is the distance of the air gap between the first lens 1 and the second lens 2 on the optical axis S; 2M L is the distance of the air gap between the second lens 2 and the super lens 3 on the optical axis S; M3 L is the distance of the air gap between the super lens 3 and the third lens 4 on the optical axis S; 34 L is the distance of the air space between the third lens 4 and the fourth lens 5 on the optical axis S; 45 L is the distance of the air space between the fourth lens 5 and the fifth lens 6 on the optical axis S; 56 is the distance of the air space between the fifth lens 6 and the sixth lens 7 on the optical axis S.

[0165] The thickness of the air space between two adjacent lenses reflects the distance between the two adjacent lenses, and the lens distance mainly affects the adjustment capability of the optical system 100 for imaging objects at different distances. In the optical system 100 provided in the present application, it is necessary to achieve clear imaging of both near and far views, so it is necessary to control the lens distance within the range of conditional formula 10, and then adjust the optical back focal length so that the optical system 100 can achieve an imaging range with a large depth of field.

[0166] In some embodiments, the optical system 100 further includes an aperture 8, which is used to control the amount of light entering the optical system 100 to ensure that the optical system 100 can work effectively and generate high-quality images. The aperture 8 is set between any two adjacent lenses; or, the aperture 8 is set on the side of the first lens 1 away from the image side. Specifically, the position where the aperture 8 is set satisfies any of the following conditions:

[0167] (1) The aperture stop 8 is provided on the object side of the first lens 1 , and the aperture stop 8 is spaced apart from the first lens 1 .

[0168] (2) The aperture 8 is disposed on the surface of the first lens 1 close to the object side, that is, the aperture 8 is attached to the surface of the first lens 1 close to the object side.

[0169] (3) The aperture 8 is provided on the surface of the first lens 1 close to the image side. That is, the aperture 8 is attached to the surface of the first lens 1 close to the image side.

[0170] (4) The aperture 8 is disposed between the first lens 1 and the second lens 2 , and there is a gap between the aperture 8 and both the first lens 1 and the second lens 2 .

[0171] (5) The aperture 8 is disposed on the surface of the second lens 2 close to the object side. That is, the aperture 8 is attached to the surface of the second lens 2 close to the object side.

[0172] (6) The aperture 8 is provided on the surface of the second lens 2 close to the image side. That is, the aperture 8 is attached to the surface of the second lens 2 close to the image side.

[0173] (7) The aperture 8 is disposed between the second lens 2 and the super lens 3 , and there is a gap between the aperture 8 and both the second lens 2 and the super lens 3 .

[0174] (8) The aperture 8 is provided on the surface of the super lens 3 close to the object side. That is, the aperture 8 is attached to the surface of the super lens 3 close to the object side.

[0175] (9) The aperture 8 is provided on the surface of the super lens 3 close to the image side. That is, the aperture 8 is attached to the surface of the super lens 3 close to the image side.

[0176] (10) The aperture 8 is provided between the super lens 3 and the third lens 4 , and there is a gap between the aperture 8 and the super lens 3 and the third lens 4 .

[0177] (11) The aperture 8 is provided on the surface of the third lens 4 close to the object side. That is, the aperture 8 is attached to the surface of the third lens 4 close to the object side.

[0178] (12) The aperture 8 is provided on the surface of the third lens 4 close to the image side. That is, the aperture 8 is attached to the surface of the third lens 4 close to the image side.

[0179] (13) The aperture 8 is disposed between the third lens 4 and the fourth lens 5 , and there is a gap between the aperture 8 and the third lens 4 and the fourth lens 5 .

[0180] (14) The aperture 8 is disposed on the surface of the fourth lens 5 close to the object side. That is, the aperture 8 is attached to the surface of the fourth lens 5 close to the object side.

[0181] (15) The aperture 8 is provided on the surface of the fourth lens 5 close to the image side. That is, the aperture 8 is attached to the surface of the fourth lens 5 close to the image side.

[0182] (16) The aperture 8 is disposed between the fourth lens 5 and the fifth lens 6 , and there is a gap between the aperture 8 and the fourth lens 5 and the fifth lens 6 .

[0183] (17) The aperture 8 is disposed on the object side surface of the fifth lens 6 , that is, the aperture 8 is attached to the surface of the fifth lens 6 close to the object side.

[0184] (18) The aperture 8 is provided on the image side surface of the fifth lens 6 , that is, the aperture 8 is attached to the surface of the fifth lens 6 close to the image side.

[0185] (19) The aperture 8 is disposed between the fifth lens 6 and the sixth lens 7 , and there is a gap between the aperture 8 and the fifth lens 6 and the sixth lens 7 .

[0186] (20) The aperture 8 is disposed on the surface of the sixth lens 7 close to the object side. That is, the aperture 8 is attached to the surface of the sixth lens 7 close to the object side.

[0187] See also Fig.34 In some embodiments, the optical system 100 further includes a filter 9, which is used to transmit visible light and filter light in other wavelength bands except visible light.

[0188] The benefits of the optical system 100 provided in this application are shown in Table 1.

[0189] Table 1. Benefits of the optical system 100 provided in this application

[0190]

[0191]

[0192] The present application illustratively provides four optical systems 100 that meet usage requirements in four embodiments. Next, the optical system 100 provided by each embodiment of the present application is described in detail.

[0193] Example 1

[0194] Figure 1 FIG. 1 shows a schematic diagram of the architecture layout of the optical system 100 provided in Example 1. Figure 1The optical system 100 includes, along the optical axis S, from the object plane A to the image plane B, an aperture 8, a first lens 1, a second lens 2, a super lens 3, a third lens 4, a fourth lens 5, a fifth lens 6, and a sixth lens 7, wherein the micro-nano structure 32 is located on the surface of the substrate 31 close to the object side, and the first lens 1, the second lens 2, the third lens 4, the fourth lens 5, the fifth lens 6, and the sixth lens 7 are all spherical lenses. Some parameters of the optical system 100 provided in Example 1 are shown in Table 2-1.

[0195] Table 2-1. Partial parameters of the optical system 100 provided in Example 1

[0196]

[0197] As can be seen from Table 2-1, the total optical length of the optical system 100 is relatively short, only 37.044 mm, so the volume of the optical system 100 provided in Example 1 is relatively small. The effective focal length of the optical system 100 is 52.68 mm, the focal length is relatively long, and the aperture number (F number) is 4.0, so the optical system 100 has a large magnification, can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. In addition, the focusing range of the optical system 100 is 3 meters to infinity, so the optical system 100 can simultaneously meet the clear imaging of close distances and long distances, and has a large depth of field.

[0198] Starting from the aperture 8, along the optical axis S from the object plane A to the image plane B, each surface in the optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 3-2.

[0199] Table 2-2. Parameters of various surfaces in the optical system 100 provided in Example 1

[0200]

[0201] For each surface in Table 2-2, surface STO is aperture 8. 11 The surface S is the surface of the first lens 1 close to the object side. 12 It is the surface of the first lens 1 close to the image side. Surface S 21 The surface S is the surface of the second lens 2 close to the object side. 22 It is the surface of the second lens 2 close to the image side. M1 The surface of the super lens 3 close to the object side. M1 , so it is recorded as a hypersurface. M2 The surface S is the surface of the super lens 3 close to the image side. 31 The surface S is the surface of the third lens 4 close to the object side. 32 It is the surface of the third lens 4 close to the image side.41 The surface S is the surface of the fourth lens 5 close to the object side. 42 It is the surface of the fourth lens 5 close to the image side. Surface S 51 The surface S is the surface of the fifth lens 6 close to the object side. 52 Surface S is the surface of the fifth lens 6 close to the image side. 61 The surface S is the surface of the sixth lens 7 close to the object side. 62 It is the surface close to the image side of the sixth lens 7. The surface Img is the image plane B of the optical system 100 when the working distance is infinity.

[0202] From Table 2-2, we can see that surface STO is a plane with an infinite radius of curvature. 11 The distance between the surface STO and the surface S is -1.885 mm, where the negative sign in "-1.885" means that the vertex of the surface of the first lens 1 close to the object side is located on the object side of the aperture 8. 11 The material between is air. 11 is a spherical surface with a radius of curvature of 12.446 mm. 11 With surface S 12 The distance between the surface S is 3.103 mm. 11 With surface S 12 The refractive index and Abbe number of the materials between are 1.570 and 68.3 respectively. 12 is a spherical surface with a radius of curvature of -29.200 mm. 12 With surface S 21 The distance between the surface S is 0.288 mm. 12 With surface S 21 The material between is air. 21 is a spherical surface with a radius of curvature of -28.090 mm. 21 With surface S 22 The distance between them is 0.782 mm, and the surface S 21 With surface S 22 The refractive index and Abbe number of the materials between are 1.885 and 37.3 respectively. 22 is a spherical surface with a radius of curvature of 155.809 mm. 22 With surface S M1 The distance between them is 0.414 mm, and the surface S 22 With surface S M1 The material between is air. M1 The radius of curvature of the surface S is infinite, so M1 is a plane, surface S M1 With surface S M2 The distance between the surface S is 0.725 mm. M1With surface S M2 The refractive index and Abbe number of the materials between are 1.446 and 67.5 respectively. M2 The radius of curvature of the surface S is infinite, so M2 is a plane, surface S M2 With surface S 31 The distance between them is 0.094 mm, and the surface S M2 With surface S 31 The material between is air. 31 is a spherical surface with a radius of curvature of 18.447 mm. 31 With surface S 32 The distance between the surface S is 1.024 mm. 31 With surface S 32 The refractive index and Abbe number of the materials between are 1.485 and 72.5 respectively. 32 is a spherical surface with a radius of curvature of 44.630 mm. 32 With surface S 41 The distance between the surface S is 9.889 mm. 32 With surface S 41 The material between is air. 41 is a spherical surface with a radius of curvature of 11.664 mm. 41 With surface S 42 The distance between the surface S is 1.126 mm. 41 With surface S 42 The refractive index and Abbe number of the materials between are 1.740 and 28.3 respectively. 42 is a spherical surface with a radius of curvature of -198.244 mm. 42 With surface S 51 The distance between the surface S is 0.860 mm. 42 With surface S 51 The material between is air. 51 is a spherical surface with a radius of curvature of -12.048 mm. 51 With surface S 52 The distance between them is 0.782 mm, and the surface S 51 With surface S 52 The refractive index and Abbe number of the materials between are 1.830 and 45.7 respectively. 52 is a spherical surface with a radius of curvature of 6.381 mm. 52 With surface S 61 The distance between the surface S is 12.086 mm. 52 With surface S 61 The material between is air. 61is a spherical surface with a radius of curvature of 152.147 mm. 61 With surface S 62 The distance between the surface S is 2.394 mm. 61 With surface S 62 The refractive index and Abbe number of the materials between are 1.485 and 72.5 respectively. 62 is a spherical surface with a radius of curvature of -10.377 mm. 62 The distance between the surface Img and the surface S is 3.477 mm. 62 The material between the surface Img is air.

[0203] See also Figure 2 , Figure 2 The phase of the metalens 3 of the optical system 100 provided in Example 1 is given, Figure 2 A two-dimensional coordinate system is established with the center of the superlens as the origin.

[0204] See also Figure 3 , Figure 3 This is a field curvature diagram when the optical system 100 provided in Example 1 works at infinity. Figure 3 The horizontal axis is the field curvature, and its unit is millimeters. Figure 3 The central vertical axis is the field of view. Figure 3 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Figure 3 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.052 mm, and the maximum sagittal field curvature is 0.028 mm.

[0205] See also Figure 4 , Figure 4 This is a distortion diagram of the optical system 100 provided in Example 1 when working at infinity. Figure 4 The horizontal axis is distortion, and its unit is percentage; Figure 4 The central vertical axis is the field of view. Figure 4 The distortion curves for wavelengths of 0.656 μm, 0.587 μm, 0.546 μm, 0.486 μm, and 0.435 μm are shown in FIG. Figure 4The five curves are too dense, so this embodiment does not distinguish the five curves. Figure 4 It can be seen that when the optical system 100 works at infinity, the maximum optical distortion in the entire field of view is less than 0.62%, and the distortion is relatively small, which basically eliminates the influence of distortion on imaging and meets the distortion requirements of the excellent imaging quality standard.

[0206] See also Figure 5 , Figure 5 This is a chromatic aberration curve diagram when the optical system 100 provided in Example 1 works at infinity. Figure 5 The middle horizontal axis is chromatic aberration, and its unit is micrometer; Figure 5 The vertical axis is the field of view angle, and its unit is degree. Figure 5 In the figure, W1 is the color difference curve of wavelength 0.656 microns, W2 is the color difference curve of wavelength 0.587 microns, W3 is the color difference curve of wavelength 0.546 microns, W4 is the color difference curve of wavelength 0.486 microns, and W5 is the color difference curve of wavelength 0.435 microns. Figure 5 It can be seen that when the optical system 100 works at infinity, within the full field of view, the maximum spherical aberration between different wavelengths is less than 5 microns, indicating that the optical system 100 has good chromatic aberration correction capability.

[0207] See also Figure 6 , Figure 6 This is a relative illumination diagram when the optical system 100 provided in Example 1 works at infinity. Figure 6 The middle horizontal axis is the field of view, and its unit is degree; Figure 6 The vertical axis is relative illumination. Figure 6 It can be seen that within the entire field of view, the relative illumination is greater than 96% and the image brightness is uniform.

[0208] See also Figure 7 , Figure 7 This is a MTF field curve diagram of the optical system 100 provided in Example 1 at 20° C. when the working distance is infinite. Figure 7 The middle horizontal axis is the image height, and the horizontal axis measures the field of view with the image height, and its unit is millimeters; Figure 7 The vertical axis is the MTF value. Figure 7 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Figure 7 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.38 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0209] See also Figure 8 , Figure 8 This is a MTF field curve diagram of the optical system 100 provided in Example 1 at -10°C when the working distance is infinite. Figure 8 The middle horizontal axis is the image height, and the horizontal axis measures the field of view with the image height, and its unit is millimeters; Figure 8 The vertical axis is the MTF value. Figure 8 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Figure 8 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.39 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0210] See also Fig. 9 , Fig. 9 This is a MTF field curve diagram of the optical system 100 provided in Example 1 at 60° C. when the working distance is infinite. Fig. 9 The middle horizontal axis is the image height, and the horizontal axis measures the field of view with the image height, and its unit is millimeters; Fig. 9 The vertical axis is the MTF value. Fig. 9 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig. 9 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.39 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0211] comprehensive Figures 7 to 9 In the temperature range of -10 to 60°C and at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.38, and the MTF value changes slightly with the change in temperature, indicating that the imaging quality of the optical system 100 provided in Example 1 is less affected by temperature, and the optical system 100 has good temperature stability and can be applied to scenes with changeable outdoor environments.

[0212] See also Fig.10 , Fig.10 This is a field curvature diagram of the optical system 100 provided in Example 1 when working at 3 meters. Fig.10 The horizontal axis is the field curvature, and its unit is millimeters. Fig.10The central vertical axis is the field of view. Fig.10 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.10 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.035 mm, and the maximum sagittal field curvature is 0.016 mm.

[0213] See also Fig.11 , Fig.11 This is a MTF field curve diagram of the optical system 100 provided in Example 1 at a working distance of 3 meters at 20°C. Fig.11 The middle horizontal axis is the image height, and the horizontal axis measures the field of view with the image height, and its unit is millimeters; Fig.11 The vertical axis is the MTF value. Fig.11 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.11 It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.36 within a 0.8 field of view (4.128 mm image height), and the imaging quality of the optical system 100 is excellent.

[0214] Example 2

[0215] Fig.12 FIG. 1 shows a schematic diagram of the architecture layout of the optical system 100 provided in Example 2. Fig.12 The optical system 100 includes, along the optical axis S from the object plane A to the image plane B, an aperture 8, a first lens 1, a second lens 2, a super lens 3, a third lens 4, a fourth lens 5, a fifth lens 6, and a sixth lens 7, wherein the micro-nano structure 32 is located on the surface of the substrate 31 close to the object side, the first lens 1, the fifth lens 6, and the sixth lens 7 are spherical lenses, and the second lens 2, the third lens 4, and the fourth lens 5 are all spherical lenses. Some parameters of the optical system 100 provided in Example 2 are shown in Table 3-1.

[0216] Table 3-1. Partial parameters of the optical system 100 provided in Example 2

[0217]

[0218] As can be seen from Table 3-1, the total optical length of the optical system 100 is relatively short, only 37.039 mm, so the volume of the optical system 100 provided in Example 2 is relatively small. The effective focal length of the optical system 100 is 52.63 mm, the focal length is relatively long, and the aperture number (F number) is 4.0, so the optical system 100 has a large magnification, can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. In addition, the focusing range of the optical system 100 is 3 meters to infinity, so the optical system 100 can simultaneously meet the clear imaging of close distances and long distances, and has a large depth of field.

[0219] Starting from the aperture 8, along the optical axis S from the object plane A to the image plane B, each surface in the optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 3-2.

[0220] Table 3-2. Parameters of various surfaces in the optical system 100 provided in Example 2

[0221]

[0222] The analysis of each surface in Table 3-2 can refer to Example 1, which will not be described in detail in this example.

[0223] See also Fig.13 , Fig.13 The phase of the metalens 3 of the optical system 100 provided in Example 2 is given, Fig.13 A two-dimensional coordinate system is established with the center of the superlens as the origin.

[0224] See also Fig.14 , Fig.14 This is a field curvature diagram when the optical system 100 provided in Example 2 works at infinity. Fig.14 The horizontal axis is the field curvature, and its unit is millimeters. Fig.14 The central vertical axis is the field of view. Fig.14 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.14It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.064 mm, and the maximum sagittal field curvature is 0.038 mm.

[0225] See also Fig.15 , Fig.15 This is a distortion diagram of the optical system 100 provided in Example 2 when working at infinity. Fig.15 The horizontal axis is distortion, and its unit is percentage; Fig.15 The central vertical axis is the field of view. Fig.15 The distortion curves for wavelengths of 0.656 μm, 0.587 μm, 0.546 μm, 0.486 μm, and 0.435 μm are shown in FIG. Fig.15 The five curves are too dense, so this embodiment does not distinguish the five curves. Fig.15 It can be seen that when the optical system 100 works at infinity, the maximum optical distortion in the entire field of view is less than 0.78%, the distortion is small, the influence of the distortion on the imaging is basically eliminated, and the distortion requirement of the excellent imaging quality standard is met.

[0226] See also Fig.16 , Fig.16 This is a chromatic aberration curve diagram when the optical system 100 provided in Example 2 works at infinity. Fig.16 The middle horizontal axis is chromatic aberration, and its unit is micrometer; Fig.16 The vertical axis is the field of view angle, and its unit is degree. Fig.16 In the figure, W1 is the color difference curve of wavelength 0.656 microns, W2 is the color difference curve of wavelength 0.587 microns, W3 is the color difference curve of wavelength 0.546 microns, W4 is the color difference curve of wavelength 0.486 microns, and W5 is the color difference curve of wavelength 0.435 microns. Fig.16 It can be seen that when the optical system 100 works at infinity, within the full field of view, the maximum spherical aberration between different wavelengths is less than 6 microns, indicating that the optical system 100 has good chromatic aberration correction capability.

[0227] See also Fig.17 , Fig.17 This is a relative illumination diagram when the optical system 100 provided in Example 2 works at infinity. Fig.17 The middle horizontal axis is the field of view, and its unit is degree; Fig.17 The vertical axis is relative illumination. Fig.17 It can be seen that within the entire field of view, the relative illumination is greater than 97% and the image brightness is uniform.

[0228] See also Fig.18 , Fig.18 This is a MTF field curve diagram of the optical system 100 provided in Example 2 at 20° C. when the working distance is infinite. Fig.18The middle horizontal axis is the field of view, and its unit is degree; Fig.18 The vertical axis is the MTF value. Fig.18 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.18 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.28 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0229] See also Fig.19 , Fig.19 This is a MTF field curve diagram of the optical system 100 provided in Example 2 at -10°C when the working distance is infinite. Fig.19 The middle horizontal axis is the field of view, and its unit is degree; Fig.19 The vertical axis is the MTF value. Fig.19 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.19 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.28 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0230] See also Fig. 20 , Fig. 20 This is a MTF field curve diagram of the optical system 100 provided in Example 2 at 60° C. when the working distance is infinite. Fig. 20 The middle horizontal axis is the field of view, and its unit is degree; Fig. 20 The vertical axis is the MTF value. Fig. 20 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig. 20 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.3 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0231] comprehensive Figures 18 to 20In the temperature range of -10 to 60°C and at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.28, and the MTF value changes slightly with the change in temperature, indicating that the imaging quality of the optical system 100 provided in Example 2 is less affected by temperature, and the optical system 100 has good temperature stability and can be applied to scenes with changeable outdoor environments.

[0232] See also Fig.21 , Fig.21 This is a field curvature diagram of the optical system 100 provided in Example 2 when working at 3 meters. Fig.21 The horizontal axis is the field curvature, and its unit is millimeters. Fig.21 The central vertical axis is the field of view. Fig.21 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.21 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.037 mm, and the maximum sagittal field curvature is 0.023 mm.

[0233] See also Fig. 22 , Fig. 22 This is a MTF field curve diagram of the optical system 100 provided in Example 2 at a working distance of 3 meters at 20°C. Fig. 22 The horizontal axis is the field of view, and its unit is degree; Fig. 22 The vertical axis is the MTF value. Fig. 22 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig. 22 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.32 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0234] Example 3

[0235] Fig.23 FIG. 1 shows a schematic diagram of the architecture layout of the optical system 100 provided in Example 3. Fig.23The optical system 100 includes, along the optical axis S, from the object plane A to the image plane B, an aperture 8, a first lens 1, a second lens 2, a super lens 3, a third lens 4, a fourth lens 5, a fifth lens 6, a sixth lens 7, and a filter 9, wherein the micro-nano structure 32 is located on the surface of the substrate 31 close to the object side, and the first lens 1, the second lens 2, the third lens 4, the fourth lens 5, the fifth lens 6, and the sixth lens 7 are all spherical lenses. Some parameters of the optical system 100 provided in Example 3 are shown in Table 4-1.

[0236] Table 4-1. Partial parameters of the optical system 100 provided in Example 3

[0237]

[0238] As can be seen from Table 4-1, the total optical length of the optical system 100 is relatively short, only 37.003 mm, so the volume of the optical system 100 provided in Example 3 is relatively small. The effective focal length of the optical system 100 is 52.64 mm, the focal length is relatively long, and the aperture number (F number) is 4.0, so the optical system 100 has a large magnification, can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. In addition, the focusing range of the optical system 100 is 3 meters to infinity, so the optical system 100 can simultaneously meet the clear imaging of close distances and long distances, and has a large depth of field.

[0239] Starting from the aperture 8, along the optical axis S from the object plane A to the image plane B, each surface in the optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 4-2.

[0240]

[0241]

[0242] The analysis of each surface in Table 4-2 can refer to Example 1, which will not be described in detail in this example.

[0243] See also Fig.24 , Fig.24 The phase of the metalens 3 of the optical system 100 provided in Example 3 is given, Fig.24 A two-dimensional coordinate system is established with the center of the superlens as the origin.

[0244] See also Fig.25 , Fig.25 This is a field curvature diagram when the optical system 100 provided in Example 3 works at infinity. Fig.25 The horizontal axis is the field curvature, and its unit is millimeters. Fig.25 The central vertical axis is the field of view. Fig.25T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.25 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.066 mm, and the maximum sagittal field curvature is 0.037 mm.

[0245] See also Fig.26 , Fig.26 This is a distortion diagram of the optical system 100 provided in Example 3 when working at infinity. Fig.26 The horizontal axis is distortion, and its unit is percentage; Fig.26 The central vertical axis is the field of view. Fig.26 The distortion curves for wavelengths of 0.656 μm, 0.587 μm, 0.546 μm, 0.486 μm, and 0.435 μm are shown in FIG. Fig.26 The five curves are too dense, so this embodiment does not distinguish the five curves. Fig.26 It can be seen that when the optical system 100 works at infinity, the maximum optical distortion in the entire field of view is less than 0.79%, the distortion is small, the influence of the distortion on the imaging is basically eliminated, and the distortion requirement of the excellent imaging quality standard is met.

[0246] See also Fig. 27 , Fig. 27 This is a chromatic aberration curve diagram when the optical system 100 provided in Example 3 works at infinity. Fig. 27 The middle horizontal axis is chromatic aberration, and its unit is micrometer; Fig. 27 The vertical axis is the field of view angle, and its unit is degree. Fig. 27 In the figure, W1 is the color difference curve of wavelength 0.656 microns, W2 is the color difference curve of wavelength 0.587 microns, W3 is the color difference curve of wavelength 0.546 microns, W4 is the color difference curve of wavelength 0.486 microns, and W5 is the color difference curve of wavelength 0.435 microns. Fig. 27 It can be seen that when the optical system 100 works at infinity, within the full field of view, the maximum spherical aberration between different wavelengths is less than 6 microns, indicating that the optical system 100 has good chromatic aberration correction capability.

[0247] See also Fig.28 , Fig.28This is a relative illumination diagram when the optical system 100 provided in Example 3 works at infinity. Fig.28 The middle horizontal axis is the field of view, and its unit is degree; Fig.28 The vertical axis is relative illumination. Fig.28 It can be seen that within the entire field of view, the relative illumination is greater than 97% and the image brightness is uniform.

[0248] See also Fig.29 , Fig.29 This is a MTF field curve diagram of the optical system 100 provided in Example 3 at 20° C. when the working distance is infinite. Fig.29 The middle horizontal axis is the field of view, and its unit is degree; Fig.29 The vertical axis is the MTF value. Fig.29 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.29 It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.2 within the entire field of view, and the imaging quality of the optical system 100 is relatively good.

[0249] See also Fig.30 , Fig.30 This is a MTF field curve diagram of the optical system 100 provided in Example 3 at -10°C when the working distance is infinite. Fig.30 The middle horizontal axis is the field of view, and its unit is degree; Fig.30 The vertical axis is the MTF value. Fig.30 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.30 It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.2 within the entire field of view, and the imaging quality of the optical system 100 is relatively good.

[0250] See also Fig.31 , Fig.31 This is a MTF field curve diagram of the optical system 100 provided in Example 3 at 60° C. when the working distance is infinite. Fig.31 The middle horizontal axis is the field of view, and its unit is degree; Fig.31 The vertical axis is the MTF value. Fig.31The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.31 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.25 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0251] comprehensive Figure 29 to Figure 31 In the temperature range of -10 to 60°C and at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.2, and the MTF value changes slightly with the change in temperature, indicating that the imaging quality of the optical system 100 provided in Example 3 is less affected by temperature, and the optical system 100 has good temperature stability and can be applied to scenes with changeable outdoor environments.

[0252] See also Fig.32 , Fig.32 This is a field curvature diagram of the optical system 100 provided in Example 3 when working at 3 meters. Fig.32 The horizontal axis is the field curvature, and its unit is millimeters. Fig.32 The central vertical axis is the field of view. Fig.32 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.32 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.042 mm, and the maximum sagittal field curvature is 0.022 mm.

[0253] See also Fig.33 , Fig.33 This is a MTF field curve diagram of the optical system 100 provided in Example 3 at a working distance of 3 meters at 20°C. Fig.33 The middle horizontal axis is the field of view, and its unit is degree; Fig.33 The vertical axis is the MTF value. Fig.33The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.33 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.3 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0254] Example 4

[0255] Fig.34 FIG. 1 shows a schematic diagram of the architecture layout of the optical system 100 provided in Example 4. Fig.34 The optical system 100 includes, along the optical axis S from the object plane A to the image plane B, an aperture 8, a first lens 1, a second lens 2, a super lens 3, a third lens 4, a fourth lens 5, a fifth lens 6, a sixth lens 7, and a filter 9, wherein the micro-nano structure 32 is located on the surface of the substrate 31 close to the object side, the first lens 1, the fifth lens 6, and the sixth lens 7 are spherical lenses, and the second lens 2, the third lens 4, and the fourth lens 5 are all aspherical lenses. Some parameters of the optical system 100 provided in Example 4 are shown in Table 5-1.

[0256] Table 5-1. Partial parameters of the optical system 100 provided in Example 4

[0257]

[0258]

[0259] As can be seen from Table 5-1, the total optical length of the optical system 100 is relatively short, only 37.476 mm, so the volume of the optical system 100 provided in Example 4 is relatively small. The effective focal length of the optical system 100 is 52.61 mm, the focal length is relatively long, and the aperture number (F number) is 4.0, so the optical system 100 has a large magnification, can obtain more detailed information, and can obtain more detailed information when observing small targets or distant targets. In addition, the focusing range of the optical system 100 is 3 meters to infinity, so the optical system 100 can simultaneously meet the clear imaging of close distances and long distances, and has a large depth of field.

[0260] Starting from the aperture 8, along the optical axis S from the object plane A to the image plane B, each surface in the optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 5-2.

[0261] Table 5-2. Parameters of various surfaces in the optical system 100 provided in Example 4

[0262]

[0263] The analysis of each surface in Table 5-2 can refer to Example 1, which will not be described in detail in this example.

[0264] Surface S 21 , surface S 21 , surface S 31 , surface S 32 , surface S 41 , surface S 42 They are all even-order aspheric surfaces, and their surface shapes satisfy the following relationship:

[0265]

[0266] Among them, Z(r) is the distance vector height from the vertex of the aspherical surface when the aspherical surface is at a height of r along the optical axis SS; c is the curvature of the aspherical surface, c = 1 / R, R is the curvature radius of the aspherical surface; k is the cone coefficient; A, B, C, D... are the aspherical coefficients. Surface S 21 , surface S 21 , surface S 31 , surface S 32 , surface S 41 , surface S 42 The values ​​of k, A, B, C, D... can be obtained from Table 2-3.

[0267] Table 5-3. Coefficients of the even-order aspheric surfaces in the optical system 100 provided in Example 4

[0268] Serial number <![CDATA[S 21 ]]> <![CDATA[S 22 ]]> <![CDATA[S 31 ]]> <![CDATA[S 32 ]]> <![CDATA[S 41 ]]> <![CDATA[S 42 ]]> k 4.50806 1.02395E+01 2.06935E+01 -1.70987E+1 -6.89744E+1 -1.54078E+1 4th order coefficient -2.58391E-04 -2.93317E-04 -3.96498E-03 -2.48895E-03 -3.70236E-03 -5.18820E-03 6th order coefficient -1.87051E-06 -2.64927E-06 2.09995E-04 1.52100E-04 2.31180E-04 4.14269E-04 8th order coefficient -1.69557E-07 -1.92066E-07 -1.29815E-05 -1.00597E-05 -3.93077E-05 -5.37597E-05 10th order coefficient -2.27806E-09 -1.77033E-09 6.04036E-07 4.31352E-07 6.47785E-06 6.30465E-06 12th order coefficients 2.91264E-10 4.13725E-10 -1.28994E-08 5.17300E-09 -1.00736E-06 -6.65901E-07 14th order coefficients -6.82212E-12 -1.07364E-11 3.58243E-10 -9.55796E-10 1.02464E-07 5.02503E-08 16th order coefficients 5.10603E-14 8.65092E-14 -4.67743E-11 -4.59125E-13 -5.74928E-09 -2.14460E-09

[0269] Refer to Table 5-3, with surface S 21 For example, k is 4.50806, A is -2.58391E-04, B is -1.87051E-06, C is -1.69557E-07, D is -2.27806E-09, E is 2.91264E-10, F is -6.82212E-12, and J is 5.10603E-14. Surface S 21 , surface S 31 , surface S 32 , surface S 41 , surface S 42 The values ​​of k, A, B, C, D, etc. can be referred to the surface S 21 It can be obtained from Table 2-3 and will not be elaborated here one by one.

[0270] See also Fig.35 , Fig.35 The phase of the metalens 3 of the optical system 100 provided in Example 4 is given, Fig.35 A two-dimensional coordinate system is established with the center of the superlens as the origin.

[0271] See also Fig.36 , Fig.36 This is a field curvature diagram when the optical system 100 provided in Example 4 works at infinity. Fig.36 The horizontal axis is the field curvature, and its unit is millimeters. Fig.36 The central vertical axis is the field of view. Fig.36 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.36 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.047 mm, and the maximum sagittal field curvature is 0.008 mm.

[0272] See also Fig.37 , Fig.37 This is a distortion diagram of the optical system 100 provided in Example 4 when working at infinity. Fig.37 The horizontal axis is distortion, and its unit is percentage; Fig.37 The central vertical axis is the field of view. Fig.37 In the figure, W1 is the distortion curve of wavelength 0.656 microns, W2 is the distortion curve of wavelength 0.587 microns, W3 is the distortion curve of wavelength 0.546 microns, W4 is the distortion curve of wavelength 0.486 microns, and W5 is the distortion curve of wavelength 0.435 microns. Fig.37 It can be seen that when the optical system 100 works at infinity, the maximum optical distortion in the entire field of view is less than 0.03%, the distortion is small, the influence of the distortion on the imaging is basically eliminated, and the distortion requirement of the excellent imaging quality standard is met.

[0273] See also Fig.38 , Fig.38 This is a chromatic aberration curve diagram when the optical system 100 provided in Example 4 works at infinity. Fig.38 The middle horizontal axis is chromatic aberration, and its unit is micrometer; Fig.38 The vertical axis is the field of view angle, and its unit is degree. Fig.38In the figure, W1 is the color difference curve of wavelength 0.656 microns, W2 is the color difference curve of wavelength 0.587 microns, W3 is the color difference curve of wavelength 0.546 microns, W4 is the color difference curve of wavelength 0.486 microns, and W5 is the color difference curve of wavelength 0.435 microns. Fig.38 It can be seen that when the optical system 100 works at infinity, within the full field of view, the maximum spherical aberration between different wavelengths is less than 6 microns, indicating that the optical system 100 has good chromatic aberration correction capability.

[0274] See also Fig.39 , Fig.39 This is a relative illumination diagram when the optical system 100 provided in Example 4 works at infinity. Fig.39 The horizontal axis is the field of view, and its unit is degree; Fig.39 The vertical axis is relative illumination. Fig.39 It can be seen that within the entire field of view, the relative illumination is greater than 98% and the image brightness is uniform.

[0275] See also Fig.40 , Fig.40 This is a MTF field curve diagram of the optical system 100 provided in Example 4 at 20° C. when the working distance is infinite. Fig.40 The horizontal axis is the field of view, and its unit is degree; Fig.40 The vertical axis is the MTF value. Fig.40 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.40 It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.4 within a 0.9 field of view (5.004°), and the imaging quality of the optical system 100 is excellent.

[0276] See also Fig.41 , Fig.41 This is a MTF field curve diagram of the optical system 100 provided in Example 4 at -10°C when the working distance is infinite. Fig.41 The horizontal axis is the field of view, and its unit is degree; Fig.41 The vertical axis is the MTF value. Fig.41 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.41It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.4 within a 0.9 field of view (5.004°), and the imaging quality of the optical system 100 is excellent.

[0277] See also Fig.42 , Fig.42 This is a MTF field curve diagram of the optical system 100 provided in Example 4 at 60° C. when the working distance is infinite. Fig.42 The horizontal axis is the field of view, and its unit is degree; Fig.42 The vertical axis is the MTF value. Fig.42 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.42 It can be seen that at a spatial frequency of 160lp / mm, the MTF of the optical system 100 is greater than 0.33 within the entire field of view, and the imaging quality of the optical system 100 is excellent.

[0278] comprehensive Figure 40 to Figure 42 In the temperature range of -10 to 60°C and at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.33, and the MTF value changes slightly with the change in temperature, indicating that the imaging quality of the optical system 100 provided in Example 4 is less affected by temperature, and the optical system 100 has good temperature stability and can be applied to scenes with changeable outdoor environments.

[0279] See also Fig.43 , Fig.43 This is a field curvature diagram of the optical system 100 provided in Example 4 when working at 3 meters. Fig.43 The horizontal axis is the field curvature, and its unit is millimeters. Fig.43 The central vertical axis is the field of view. Fig.43 T1 is the meridian field curvature curve with a wavelength of 0.656 microns, S1 is the sagittal field curvature curve with a wavelength of 0.656 microns; T2 is the meridian field curvature curve with a wavelength of 0.587 microns, S2 is the sagittal field curvature curve with a wavelength of 0.587 microns; T3 is the meridian field curvature curve with a wavelength of 0.546 microns, S3 is the sagittal field curvature curve with a wavelength of 0.546 microns; T4 is the meridian field curvature curve with a wavelength of 0.486 microns, S4 is the sagittal field curvature curve with a wavelength of 0.486 microns; T5 is the meridian field curvature curve with a wavelength of 0.435 microns, S5 is the sagittal field curvature curve with a wavelength of 0.435 microns. Fig.43 It can be seen that when the optical system 100 works at infinity, the maximum meridian field curvature of the whole field of view is 0.043 mm, and the maximum sagittal field curvature is 0.010 mm.

[0280] See also Fig.44 , Fig.44 This is a MTF field curve diagram of the optical system 100 provided in Example 4 at a working distance of 3 meters at 20°C. Fig.44 The horizontal axis is the field of view, and its unit is degree; Fig.44 The vertical axis is the MTF value. Fig.44 The MTF of 40lp / mm spatial frequency with field of view changes in sagittal curve S1 and meridional curve T1, the MTF of 80lp / mm spatial frequency with field of view changes in sagittal curve S2 and meridional curve T2, the MTF of 160lp / mm spatial frequency with field of view changes in sagittal curve S3 and meridional curve T3. Fig.44 It can be seen that at a spatial frequency of 160 lp / mm, the MTF of the optical system 100 is greater than 0.4 within a 0.8 field of view (4.448°), and the imaging quality of the optical system 100 is excellent.

[0281] After summarizing the various parameters of the optical system 100 provided by the above four embodiments, the following Table 6 is obtained. Table 6 is mainly used to illustrate that various conditions satisfied by the optical system 100 provided by the present application are all verified and supported by experiments.

[0282] Table 6. Parameters of the optical system 100 provided in various embodiments

[0283]

[0284]

[0285]

[0286] The present application also provides an optical lens (not shown), which includes an image sensor (not shown) and the above-mentioned optical system 100. The image sensor is arranged on the image plane B of the optical system 100, and the image sensor includes but is not limited to CMOS (Complementary Metal Oxide Semiconductor, CMOS for short) and CCD (Charge Coupled Device, CCD for short). The optical lens has the advantages of simple structure, small size, light weight, low cost, large depth of field, and the ability to obtain more details. The scope of application of the optical lens includes but is not limited to drones.

[0287] In some embodiments, the image sensor is disposed on the image plane of the optical system 100 at a working distance of 3 meters.

[0288] In some embodiments, the image sensor is disposed on the image plane of the optical system 100 at an infinite working distance.

[0289] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the utility model disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the appended claims.

Claims

1. An optical system, characterized in that: The optical system includes, from the object side to the image side along the optical axis, a first lens, a second lens, a super lens, a third lens, a fourth lens, a fifth lens and a sixth lens; The optical focal power of the first lens is positive, and the surface of the first lens close to the object side is convex toward the object side; the optical focal power of the super lens is positive; the optical focal power of the fourth lens is positive; the optical focal power of the fifth lens is negative, and the surface of the fifth lens close to the object side is convex toward the image side, and the surface of the fifth lens close to the image side is convex toward the object side; the optical focal power of the sixth lens is positive, and the surface of the sixth lens close to the object side is convex toward the object side, and the surface of the sixth lens close to the image side is convex toward the image side.

2. The optical system according to claim 1, characterized in that The optical system satisfies: Wherein, f1 is the focal length of the first lens, n6 is the refractive index of the sixth lens, and RS 11 is the radius of curvature of the surface of the first lens close to the object side, and the RS 62 is the radius of curvature of the surface of the sixth lens close to the image side.

3. The optical system according to claim 1, characterized in that The optical system satisfies: Wherein, the FNO is the aperture number of the optical system, is the maximum phase difference of the metalens, and the R M is the effective radius of the super lens, the DS6 is the effective diameter of the sixth lens, and the EPD is the entrance pupil diameter of the optical system.

4. The optical system according to claim 1, characterized in that The optical system satisfies: Wherein, the first lens, the second lens, the super lens and the third lens form a first lens group, the f A is the effective focal length of the first lens group; the fifth lens and the sixth lens form a second lens group, and the f B is the effective focal length of the second lens group.

5. The optical system according to claim 1, characterized in that The optical system satisfies: Among them, the θ i is the maximum incident angle of the marginal ray of the maximum field of view on the surface of the fourth lens close to the object side, the θ r It is the maximum exit angle of the marginal light with the maximum field of view on the surface of the fifth lens close to the image side.

6. The optical system according to claim 1, characterized in that The optical system satisfies: Among them, the CT4 is the center thickness of the fourth lens, and the ET4 is the edge thickness of the fourth lens; the ET5 is the edge thickness of the fifth lens, and the CT5 is the center thickness of the fifth lens.

7. The optical system according to claim 1, characterized in that The optical system satisfies: Wherein, the TTL is the total optical length of the optical system, and f is the effective focal length of the optical system.

8. The optical system according to claim 1, characterized in that The optical system satisfies: 0.9mm≤ΔBFL≤0.94mm; The ΔBFL is the difference between the optical back focal length of the optical system at the shortest working distance and the optical back focal length of the optical system at the farthest working distance.

9. The optical system according to any one of claims 1 to 8, characterized in that: The optical system satisfies: Wherein, f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f M is the focal length of the super lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens; f5 is the focal length of the fifth lens; f6 is the focal length of the sixth lens, and f is the effective focal length of the optical system.

10. The optical system according to any one of claims 1 to 8, characterized in that: The optical system satisfies: 1.45≤nd1≤1.6,65≤vd1≤82; 1.50≤nd2≤1.93,30≤vd2≤60; 1.44≤nd M ≤1.49,65≤vd M ≤70; 1.46≤nd3≤1.7,21≤vd3≤80; 1.6≤nd4≤1.75, 21≤vd4≤30; 1.55≤nd5≤1.85,38≤vd5≤70; 1.46≤nd6≤1.55,69≤vd6≤85; Wherein, nd1 is the refractive index of the first lens, vd1 is the Abbe number of the first lens; nd2 is the refractive index of the second lens, vd2 is the Abbe number of the second lens; M is the refractive index of the metalens, and vd M is the Abbe number of the super lens; the nd3 is the refractive index of the third lens, and the vd3 is the Abbe number of the third lens; the nd4 is the refractive index of the fourth lens, and the vd4 is the Abbe number of the fourth lens; the nd5 is the refractive index of the fifth lens, and the vd5 is the Abbe number of the fifth lens; the nd6 is the refractive index of the sixth lens, and the vd6 is the Abbe number of the sixth lens.

11. The optical system according to any one of claims 1 to 8, characterized in that: The optical system satisfies: 0.06mm≤L 12 ≤0.3mm; 0.3mm≤L 2M ≤0.45mm; 0.05mm≤L M3 ≤3.3mm; 7.8mm≤L 34 ≤10mm; 0.2mm≤L 45 ≤0.9mm; 11.2mm≤L 56 ≤13.1mm; Among them, the L 12 is the distance of the air gap between the first lens and the second lens on the optical axis; the L 2M is the distance of the air gap between the second lens and the super lens on the optical axis; the L M3 is the distance of the air gap between the super lens and the third lens on the optical axis; 34 is the distance of the air space between the third lens and the fourth lens on the optical axis; 45 is the distance of the air space between the fourth lens and the fifth lens on the optical axis; 56 is the distance of the air space between the fifth lens and the sixth lens on the optical axis.

12. The optical system according to any one of claims 1 to 8, characterized in that: The optical system further includes an aperture, and the aperture is disposed between any two adjacent lenses; or, the aperture is disposed on a side of the first lens away from the image side.

13. An optical lens, characterized in that: include: An image sensor and an optical system as claimed in any one of claims 1 to 12; The image sensor is arranged on the image plane of the optical system.

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