A day and night all-around fisheye lens

Abstract

The application discloses a day and night dual-use panoramic fisheye lens. The lens comprises, from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens; the nine lenses are coated with a film with a wavelength of 420-900 nm, and the maximum reflectivity is less than 1%; the first lens has a negative refractive power, the object side is a convex surface, and the image side is a concave surface; the second lens has a negative refractive power, the object side is a convex surface, and the image side is a concave surface, and the like. The application adopts a multiple structure, increases an infrared 850 nm spectral wavelength, optimizes night imaging quality, and realizes day and night dual-use functions. Further, three double-cemented lenses are used to optimize infrared defocus and system chromatic aberration. Meanwhile, the film coating requirement of the optical system lens is 420-900 nm, and Rmax<1%; Rmax is the maximum reflectivity value. The setting makes the lens support high antireflection effects of visible light and infrared IR850 nm at the same time, reduces lens surface energy loss, and increases light energy utilization.

Description

Technical Field

[0001] This invention relates to the field of fisheye lens technology, and more particularly to a panoramic fisheye lens that can be used both day and night. Background Technology

[0002] Infrared fisheye lenses are special lenses with a field of view of up to 180 degrees. They play an important role in sky monitoring, forest fire prevention, public security and border defense, regional monitoring (such as airport substations), pipeline inspection, etc. However, existing lenses have a relatively large IR defocus, and there is still room for improvement in infrared performance. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a day and night dual-use panoramic fisheye lens, which can solve at least one of the technical problems mentioned in the background art.

[0004] According to one aspect of the present invention, a day and night dual-use panoramic fisheye lens is provided, comprising, from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens; the nine lenses are coated with a wavelength of 420-900nm and have a maximum reflectivity of less than 1%;

[0005] The first lens has negative refractive power, with a convex object side and a concave image side;

[0006] The second lens has negative refractive power, with a convex object side and a concave image side;

[0007] The third lens has negative refractive power, with a concave object side and a convex image side;

[0008] The fourth lens has positive refractive power, with a concave object side and a convex image side;

[0009] The fifth lens has positive refractive power and a convex object-side surface.

[0010] The sixth lens has positive refractive power, and the object side and image side are both convex.

[0011] The seventh lens has negative refractive power, with a concave object side and a convex image side;

[0012] The eighth lens has positive refractive power, and the object side and image side are both convex.

[0013] The ninth lens has negative refractive power, with a concave object side and a convex image side;

[0014] The image-side surface of the third lens and the object-side surface of the fourth lens are glued together.

[0015] The image-side surface of the sixth lens and the object-side surface of the seventh lens are glued together.

[0016] The image-side surface of the eighth lens is bonded to the object-side surface of the ninth lens.

[0017] The above technical solution employs a multi-layered structure to increase the infrared 850nm wavelength, optimizing nighttime imaging quality and achieving day and night dual-use functionality. Furthermore, a three-element cemented doublet lens is used to optimize infrared defocus and system chromatic aberration. Simultaneously, the optical system lens coating requires a wavelength of 420-900nm and an Rmax < 1%; where Rmax is the maximum reflectivity value. This configuration allows the lens to simultaneously support high anti-reflection effects for both visible light and infrared IR850nm, reducing energy loss at the lens surface and increasing light energy utilization.

[0018] In some embodiments, the lens satisfies the following formula:

[0019] 1.0 <R1 / R2<6.0

[0020] 3.1 <R3 / R4<6.9

[0021] 1.8 <D2 / R2<1.9

[0022] 1.5 <D4 / R4<1.7

[0023] In the formula, R1 and R2 are the curvature radii of the object side and the image side of the first lens, respectively; R3 and R4 are the curvature radii of the object side and the image side of the second lens, respectively; and D2 and D4 are the effective light-transmitting apertures of the image side of the first lens and the image side of the second lens, respectively.

[0024] In the above technical solution, a large-aperture optical system architecture is adopted, and the spherical aberration of the large aperture is optimized by limiting the radius of curvature of the lenses in the optical system. Furthermore, a two-pixel hat-shaped lens design is used to increase the field of view of the optical system, achieving a maximum field of view of 180 degrees. Combined with a 1” 360-degree panoramic fisheye camera, a panoramic fisheye effect is achieved. Simultaneously, the first lens can correct the distortion of the optical system.

[0025] In some embodiments, the lens satisfies the following formula:

[0026] Nd1>1.85

[0027] 6.0 <D1 / f<8.7

[0028] In the formula, Nd1 is the refractive index parameter of the first lens, D1 is the effective aperture of the front surface of the first lens, and f is the focal length of the lens.

[0029] In the above technical solution, the first piece uses a high refractive index glass grade, which reduces the effective light transmission aperture and thus reduces the outer diameter of the optical system.

[0030] In some embodiments, the lens further includes an aperture stop disposed between the fifth lens and the sixth lens; and

[0031] The lens satisfies the following formula:

[0032] 2.6 <CT9+CT 10 <4.0

[0033] 0 <CT7<0.15

[0034] 0 <CT 13 <0.15

[0035] In the formula, CT7 is the air gap between the fourth and fifth lenses, CT9 is the gap between the fifth lens and the aperture stop, and CT... 10 The distance between the aperture stop and the sixth lens, CT 13 This is the air gap between the seventh and eighth lenses.

[0036] In the above technical solution, the aperture position space can accommodate a variable aperture component, enabling automatic aperture control adjustment according to environmental changes. Furthermore, a compact optical system architecture is adopted to reduce the air gap except for the space below the concave surface at the aperture position, limiting the overall length of the optical system and thus achieving the compact miniaturization requirement.

[0037] In some embodiments, the lens satisfies the following formula:

[0038] 1.4 <BFL / f<1.9

[0039] 9.0 <TTL / f<13.0

[0040] In the formula, BFL is the distance from the vertex of the side image of the ninth lens to the imaging plane, and f is the focal length of the lens.

[0041] In the above technical solutions, satisfying the formula allows for a shorter overall optical length of the lens and reduced assembly sensitivity. Furthermore, controlling the BFL (Browser Flange) ensures the lens and camera can be matched without mechanical interference. Controlling the overall length is for achieving a compact size and a robust system.

[0042] In some embodiments, the lens satisfies the following formula:

[0043] 7 <Vd3-Vd4<13

[0044] 45 <Vd6-Vd7<55

[0045] 44 <Vd8-Vd9<56

[0046] In the formula, Vd3, Vd4, Vd6, Vd7, Vd8, and Vd9 are the Abbe coefficients of the third, fourth, sixth, seventh, eighth, and ninth lenses, respectively.

[0047] In the above technical solution, satisfying the above formula can enable the various lens combinations of the system to correct chromatic aberration, which helps to eliminate the influence of chromatic aberration, reduce field curvature, and correct coma.

[0048] In some embodiments, the lens satisfies the following formula:

[0049] 0.63 <PgF1<0.66

[0050] 0.60 <PgF7<0.66

[0051] 0.61 <PgF9<0.68

[0052] In the formula, PgF1, PgF7, and PgF9 are the dispersion shift coefficients of the first lens, the seventh lens, and the ninth lens, respectively.

[0053] In the above technical solution, in order to further optimize infrared defocus and system chromatic aberration, the dispersion shift coefficients of the three lenses of the lens are further limited.

[0054] In some embodiments, the seventh lens is made of glass material with a positive Dn / Dt value, while the sixth and eighth lenses are made of glass material with a negative Dn / Dt value.

[0055] In the above technical solution, athermal analysis is introduced, and temperature drift caused by the optical system base is compensated by using glass with positive and negative coefficients of thermal expansion. While meeting mechanical structural requirements, the optical back cutoff is minimized as much as possible, thus enabling the optical system to achieve clear imaging in the range of -40℃ to +85℃. The seventh lens uses glass material with a positive Dn / Dt value, while the sixth and eighth lenses use glass material with a negative Dn / Dt value, to compensate for the temperature drift changes caused by the remaining base and other lenses, thereby achieving stable imaging without defocusing at high and low temperatures ranging from -40℃ to +85℃.

[0056] In some embodiments, the lens satisfies the following formula:

[0057] 350 <Fno*FOV<370

[0058] In the formula, Fno is the ratio of the effective focal length of the lens to the entrance pupil diameter, and FOV is the maximum field of view of the lens.

[0059] In the above technical solution, by controlling the F-number numerical aperture and the field of view of the optical system, the pupil amount of the optical system meets certain requirements. This satisfies the light-gathering capability of the optical system and the object-side aperture range that the optical system can detect. If the field of view is too small, the observed object cannot be fully detected; if the field of view is too large, it can easily reduce the observation accuracy.

[0060] In some embodiments, the first lens to the ninth lens are all spherical mirrors.

[0061] In the above technical solution, the lens adopts a global glass surface design, which reduces the difficulty of lens processing and the production cost of the optical system. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 This is a schematic diagram of the lens structure of one embodiment of the day and night panoramic fisheye lens of the present invention;

[0064] Figure 2 This is a lens optical path diagram of one embodiment of the day and night panoramic fisheye lens of the present invention;

[0065] Figure 3 This is a visible MTF curve of one embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0066] Figure 4 This is an infrared 850nm MTF curve of one embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0067] Figure 5 This is a visible field distortion image of one embodiment of the day and night panoramic fisheye lens of the present invention;

[0068] Figure 6 This is a chromatic aberration diagram of one embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0069] Figure 7 This is a visible star map of one embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0070] Figure 8 This is an infrared 850nm star pattern of one embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0071] Figure 9This is a schematic diagram of the lens structure of a second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0072] Figure 10 This is a lens optical path diagram of a second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0073] Figure 11 This is a visible MTF curve of a second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0074] Figure 12 This is the infrared 850nm MTF curve of the second embodiment of the day and night panoramic fisheye lens of the present invention;

[0075] Figure 13 This is a visible field distortion image of a second embodiment of the day and night panoramic fisheye lens of the present invention;

[0076] Figure 14 This is a chromatic aberration diagram of a second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0077] Figure 15 This is a visible star map of a second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0078] Figure 16 This is an infrared 850nm star pattern of the second embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0079] Figure 17 This is a schematic diagram of the lens structure of a third embodiment of the day and night panoramic fisheye lens of the present invention;

[0080] Figure 18 This is the lens optical path diagram of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0081] Figure 19 This is a visible MTF curve of the third embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0082] Figure 20 This is the infrared 850nm MTF curve of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0083] Figure 21 This is a visible field distortion image of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0084] Figure 22 This is a chromatic aberration diagram of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0085] Figure 23 This is a visible star map of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0086] Figure 24 This is an infrared 850nm star pattern of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0087] Figure 25 This is a schematic diagram of the lens structure of a third embodiment of the day and night panoramic fisheye lens of the present invention;

[0088] Figure 26 This is the lens optical path diagram of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0089] Figure 27 This is a visible MTF curve of the third embodiment of the day and night dual-use panoramic fisheye lens of the present invention;

[0090] Figure 28 This is the infrared 850nm MTF curve of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0091] Figure 29 This is a visible field distortion image of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0092] Figure 30 This is a chromatic aberration diagram of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0093] Figure 31 This is a visible star map of the third embodiment of the day and night panoramic fisheye lens of the present invention;

[0094] Figure 32 This is an infrared 850nm star pattern of the third embodiment of the day and night panoramic fisheye lens of the present invention; Detailed Implementation

[0095] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the invention. Similarly, the following embodiments are only some, not all, embodiments of the present invention, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0096] This invention provides a panoramic fisheye lens that can be used both day and night, which can solve at least one of the technical problems mentioned in the background art.

[0097] Example 1

[0098] Please see Figures 1 to 2This embodiment describes a panoramic fisheye day / night dual-use lens, consisting of, from the object-side OBJ to the image-side IMA, the following lenses in sequence: first lens L1, second lens L2, third lens L3, fourth lens L4, fifth lens L5, aperture ST, sixth lens L6, seventh lens L7, eighth lens L8, ninth lens L9, and protective sheet G.

[0099] The first lens L1 has negative refractive power, with an object-side surface 1 being convex and an image-side surface 2 being concave; the second lens L2 has negative refractive power, with an object-side surface 3 being convex and an image-side surface 4 being concave; the third lens L3 has negative refractive power, with an object-side surface 5 being concave and an image-side surface 6 being convex; the fourth lens L4 has positive refractive power, with an object-side surface 6 being concave and an image-side surface 7 being convex; the fifth lens L5 has positive refractive power, with an object-side surface 8 being convex; the sixth lens L6 has positive refractive power, with an object-side surface 11 being convex and an image-side surface 7 being convex. Side 12 is convex; the seventh lens L7 has negative refractive power, with object side 12 being concave and image side 13 being convex; the eighth lens L8 has positive refractive power, with object side 14 being convex and image side 15 being convex; the ninth lens L9 has negative refractive power, with object side 15 being concave and image side 16 being convex; this optical imaging lens has only the above nine lenses with refractive power, and the aperture ST is located between the fifth lens L5 and the sixth lens L6, and can be set as a fixed aperture or a variable aperture. Specifically, the image side of the third lens L3 is cemented to the object side of the fourth lens L4; the image side of the sixth lens L6 is cemented to the object side of the seventh lens L7; and the image side of the eighth lens L8 is cemented to the object side of the ninth lens L9.

[0100] In this embodiment, the lens focal length is 2.3mm, the FOV is 180°, and the TTL is 26.5mm. For other parameters, please refer to the table below (the numbers in the table correspond to the numbers in the figure, and the same applies below):

[0101] Table 1 Lens-related parameters in one of the embodiments.

[0102] 1 First lens 15.75 1.9 Glass 1.9 18 -8.5 -3.7 2 5.03 2.7 3 Second lens 19.02 0.8 Glass 1.75 52 -6.5 -2.8 4 3.83 3.0 5 Third lens -5.34 0.8 Glass 1.65 34 -13.8 -6.0 6 Fourth lens -14.09 1.3 Glass 2.0 25 15.0 6.5 7 -7.62 0.1 8 Fifth lens 8.70 2.0 Glass 2.0 25 8.2 3.6 9 -117.47 1.5 10 STO Infinity 2.0 11 Sixth lens 93.81 1.7 Glass 1.6 68 4.9 12 Seventh Lens -3.00 0.8 Glass 2.0 19 -8.2 13 -5.34 0.1 14 Eighth lens 7.17 2.1 Glass 1.6 68 5.8 2.5 15 Ninth Lens -5.82 2.1 Glass 1.9 18 -11.1 -4.8 16 -15.29 0.9 17 Protective glass Infinity 0.8 Glass 1.5 64 18 Infinity 2.0 IMA Imaging surface Infinity

[0103] Please see Figure 3 The MTF (Mean Transmission Format) of the visible light center field of view is greater than 0.6 at 200 lp / mm, the MTF of the 52° field of view is greater than 0.3 at 200 lp / mm, and the MTF of the 90° field of view is greater than 0.19 at 200 lp / mm. This figure shows that the optical system has good resolution and, when paired with a 1-inch 360° panoramic fisheye camera, can basically meet practical usage requirements.

[0104] Please see Figure 4The MTF (Mean Transmission Format) at the center field of view of the infrared 850nm is greater than 0.3 at 200 lp / mm, the MTF at the 52° field of view is greater than 0.3 at 200 lp / mm, and the MTF at the 90° field of view is greater than 0.15 at 200 lp / mm. This figure indicates that the optical system performs well at night and can meet the requirements of practical applications.

[0105] Please see Figure 5 The left image shows the field curvature diagram. It clearly shows that the field curvature of this panoramic fisheye day / night lens is within 0.1mm. Within a 0.8F field of view, the meridional and sagittal rays of the lens almost coincide, indicating good astigmatism correction. Astigmatism across the entire field of view is approximately 0.08mm. The right image shows the F-Thete distortion diagram. It clearly shows that the lens's F-Thete distortion is within -5%, and the image is optimized through projection mapping to meet practical usage requirements.

[0106] Please see Figure 6 As can be seen from the figure, the maximum chromatic aberration of this lens is 5um, which is good. The lens does not produce a particularly obvious purple fringing phenomenon for visible light, and the color reproduction is high.

[0107] Please see Figure 7 As shown in the figure, the root mean square radius of the visible light spot of this lens is 2.119 μm, approximately equal to the size of one pixel, and the geometric spot radius is 7.014 μm, approximately the size of three pixels. This indicates that the optical system exhibits relatively small spherical aberration and high resolution.

[0108] Please see Figure 8 As shown in the figure, the root mean square radius of the infrared spot of this lens is 1.421 μm, which is less than one pixel in size, and the geometric spot radius is 2.089 μm, which is also approximately one pixel in size. This indicates that the optical system has relatively small spherical aberration and high resolution.

[0109] Example 2

[0110] Please see Figures 9 to 10 This embodiment is a panoramic fisheye day and night dual-use lens, which differs from one of the embodiments in that the lens-related parameters are different.

[0111] In this embodiment, the lens focal length is 2.3mm, the FOV is 180°, and the TTL is 26.5mm. For other parameters, please refer to the table below (the numbers in the table correspond to the numbers in the diagram):

[0112] Table 2 Lens-related parameters in Example 2

[0113] 1 First lens 15.72 2.2 Glass 1.9 18 -8.7 -3.8 2 5.04 2.8 3 Second lens 20.13 0.8 Glass 1.8 47 -6.1 -2.7 4 3.89 2.9 5 Third lens -5.64 0.8 Glass 1.64 35 -12.5 -5.4 6 Fourth lens -20.18 1.3 Glass 2.0 25 12.9 5.6 7 -8.11 0.1 8 Fifth lens 7.99 2.1 Glass 2.0 25 8.1 3.5 9 458.93 1.4 10 STO Infinity 1.8 11 Sixth lens 420.68 1.7 Glass 1.6 68 4.8 12 Seventh Lens -2.84 0.8 Glass 2.0 19 -7.7 13 -5.12 0.1 14 Eighth lens 7.11 2.1 Glass 1.6 68 5.7 2.5 15 Ninth Lens -5.78 1.8 Glass 1.9 18 -11.5 -5.0 16 -14.21 1.0 17 Protective glass Infinity 0.8 Glass 1.5 64 18 Infinity 2.0 IMA Imaging surface Infinity

[0114] Please see Figure 11The MTF (Mean Transmission Format) of the visible light center field of view is greater than 0.6 at 200 lp / mm, the MTF of the 52° field of view is greater than 0.33 at 200 lp / mm, and the MTF of the 90° field of view is greater than 0.25 at 200 lp / mm. This figure shows that the optical system has good resolution and, when paired with a 1-inch 360° panoramic fisheye camera, can basically meet practical usage requirements.

[0115] Please see Figure 12 The MTF (Mean Transmission Format) at the center field of view of the infrared 850nm is greater than 0.25 at 200 lp / mm, the MTF at the 52° field of view is greater than 0.28 at 200 lp / mm, and the MTF at the 90° field of view is greater than 0.15 at 200 lp / mm. This figure indicates that the optical system performs well at night and can meet the requirements of practical applications.

[0116] Please see Figure 13 The left image shows the field curvature diagram. It clearly shows that the field curvature of this panoramic fisheye day / night lens is within 0.1mm. Within a 0.8F field of view, the meridional and sagittal rays of the lens almost coincide, indicating good astigmatism correction. Astigmatism across the entire field of view is approximately 0.08mm. The right image shows the F-Thete distortion diagram. It clearly shows that the lens's F-Thete distortion is within -5%, and the image is optimized through projection mapping to meet practical usage requirements.

[0117] Please see Figure 14 As can be seen from the figure, the maximum chromatic aberration of this lens is 5um, which is good. The lens does not produce a particularly obvious purple fringing phenomenon for visible light, and the color reproduction is high.

[0118] Please see Figure 15 As shown in the figure, the root mean square radius of the visible light spot of this lens is 2.368 μm, approximately equal to the size of one pixel, and the geometric spot radius is 7.345 μm, approximately the size of three pixels. This indicates that the optical system exhibits relatively small spherical aberration and high resolution.

[0119] Please see Figure 16 As shown in the figure, the root mean square radius of the infrared spot of this lens is 1.648 μm, which is less than one pixel in size, and the geometric spot radius is 2.521 μm, which is also approximately one pixel in size. This indicates that the optical system has relatively small spherical aberration and high resolution.

[0120] Example 3

[0121] Please see Figures 17 to 18 This embodiment is a panoramic fisheye day and night dual-use lens, which differs from one of the embodiments in that the lens-related parameters are different.

[0122] In this embodiment, the lens focal length is 2.3mm, the FOV is 180°, and the TTL is 26.54mm. For other parameters, please refer to the table below (the numbers in the table correspond to the numbers in the diagram):

[0123] Table 3. Parameters related to the three lenses in the embodiment.

[0124] 1 First lens 15.70 2.2 Glass 1.9 18 -8.7 2 5.04 2.8 3 Second lens 20.12 0.8 Glass 1.8 47 -6.1 -2.7 4 3.89 2.9 5 Third lens -5.64 0.8 Glass 1.64 35 -12.5 -5.4 6 Fourth lens -20.25 1.3 Glass 2.0 25 12.8 5.6 7 -8.11 0.1 8 Fifth lens 7.99 2.1 Glass 2.0 25 8.1 3.5 9 456.01 1.4 10 STO Infinity 1.8 11 Sixth lens 416.99 1.7 Glass 1.6 68 4.7 12 Seventh Lens -2.84 0.8 Glass 2.0 19 -7.7 13 -5.12 0.1 14 Eighth lens 7.11 2.1 Glass 1.6 68 5.7 15 Ninth Lens -5.77 1.8 Glass 1.9 18 -11.4 -5.0 16 -14.21 1.0 17 Protective glass Infinity 0.8 Glass 1.5 64 18 Infinity 2.0 IMA Imaging surface Infinity

[0125] Please see Figure 19 The MTF (Mean Transmission Format) of the visible light center field of view is greater than 0.6 at 200 lp / mm, the MTF of the 52° field of view is greater than 0.3 at 200 lp / mm, and the MTF of the 90° field of view is greater than 0.19 at 200 lp / mm. This figure shows that the optical system has good resolution and, when paired with a 1-inch 360° panoramic fisheye camera, can basically meet practical usage requirements.

[0126] Please see Figure 20 The MTF (Mean Transmission Format) at the center field of view of the infrared 850nm is greater than 0.25 at 200 lp / mm, the MTF at the 52° field of view is greater than 0.28 at 200 lp / mm, and the MTF at the 90° field of view is greater than 0.15 at 200 lp / mm. This figure indicates that the optical system performs well at night and can meet the requirements of practical applications.

[0127] Please see Figure 21 The left image shows the field curvature diagram. It clearly shows that the field curvature of this panoramic fisheye day / night lens is within 0.1mm. Within a field of view of 0.82F, the meridional and sagittal rays of the lens almost coincide, indicating good astigmatism correction. Astigmatism across the entire field of view is approximately 0.08mm. The right image shows the F-Thete distortion diagram. It clearly shows that the lens's F-Thete distortion is within -5%, and the image is optimized through projection mapping to meet practical usage requirements.

[0128] Please see Figure 22 As can be seen from the figure, the maximum chromatic aberration of this lens is 5um, which is good. The lens does not produce a particularly obvious purple fringing phenomenon for visible light, and the color reproduction is high.

[0129] Please see Figure 23 As shown in the figure, the root mean square radius of the visible light spot of this lens is 2.348 μm, approximately equal to the size of one pixel, and the geometric spot radius is 7.306 μm, approximately the size of three pixels. This indicates that the optical system exhibits relatively small spherical aberration and high resolution.

[0130] Please see Figure 24As shown in the figure, the root mean square radius of the infrared spot of this lens is 1.644 μm, which is less than one pixel in size, and the geometric spot radius is 2.481 μm, which is also approximately one pixel in size. This indicates that the optical system has relatively small spherical aberration and high resolution.

[0131] Example 4

[0132] Please see Figures 25 to 26 This embodiment is a panoramic fisheye day and night dual-use lens, which differs from one of the embodiments in that the lens-related parameters are different.

[0133] In this embodiment, the lens focal length is 2.3mm, the FOV is 180°, and the TTL is 26.55mm. For other parameters, please refer to the table below (the numbers in the table correspond to the numbers in the diagram):

[0134] Table 3. Parameters related to the three lenses in the embodiment.

[0135] 1 First lens 15.70 2.2 Glass 1.9 18 -8.7 2 5.04 2.8 3 Second lens 20.24 0.8 Glass 1.8 47 -6.1 -2.7 4 3.89 2.9 5 Third lens -5.64 0.8 Glass 1.64 35 -12.4 -5.4 6 Fourth lens -20.21 1.3 Glass 2.0 25 12.8 5.6 7 -8.11 0.1 8 Fifth lens 7.99 2.1 Glass 2.0 25 8.1 3.5 9 455.99 1.4 10 STO Infinity 1.8 11 Sixth lens 416.78 1.7 Glass 1.6 68 4.7 12 Seventh Lens -2.84 0.8 Glass 2.0 19 -7.7 13 -5.12 0.1 14 Eighth lens 7.11 2.1 Glass 1.6 68 5.7 15 Ninth Lens -5.77 1.8 Glass 1.9 18 -11.4 -5.0 16 -14.28 1.0 17 Protective glass Infinity 0.8 Glass 1.5 64 18 Infinity 2.0 IMA Imaging surface Infinity

[0136] Please see Figure 27 The MTF (Mean Transmission Format) of the visible light center field of view is greater than 0.6 at 200 lp / mm, the MTF of the 52° field of view is greater than 0.33 at 200 lp / mm, and the MTF of the 90° field of view is greater than 0.25 at 200 lp / mm. This figure shows that the optical system has good resolution and, when paired with a 1-inch 360° panoramic fisheye camera, can basically meet practical usage requirements.

[0137] Please see Figure 28 The MTF (Mean Transmission Format) at the center field of view of the infrared 850nm is greater than 0.25 at 200 lp / mm, the MTF at the 52° field of view is greater than 0.27 at 200 lp / mm, and the MTF at the 90° field of view is greater than 0.15 at 200 lp / mm. This indicates that the optical system performs well at night and can meet the requirements of practical applications.

[0138] Please see Figure 29 The left image shows the field curvature diagram. It clearly shows that the field curvature of this panoramic fisheye day / night lens is within 0.1mm. Within a 0.8F field of view, the meridional and sagittal rays of the lens almost coincide, indicating good astigmatism correction. Astigmatism across the entire field of view is approximately 0.08mm. The right image shows the F-Thete distortion diagram. It clearly shows that the lens's F-Thete distortion is within -5%, and the image is optimized through projection mapping to meet practical usage requirements.

[0139] Please see Figure 30 As can be seen from the figure, the maximum chromatic aberration of this lens is 5um, which is good. The lens does not produce a particularly obvious purple fringing phenomenon for visible light, and the color reproduction is high.

[0140] Please see Figure 31 As shown in the figure, the root mean square radius of the visible light spot of this lens is 2.358 μm, approximately equal to the size of one pixel, and the geometric spot radius is 7.358 μm, approximately the size of three pixels. This indicates that the optical system exhibits relatively small spherical aberration and high resolution.

[0141] Please see Figure 32 As shown in the figure, the root mean square radius of the infrared spot of this lens is 1.607 μm, which is less than one pixel in size, and the geometric spot radius is 2.401 μm, which is also approximately one pixel in size. This indicates that the optical system has relatively small spherical aberration and high resolution.

[0142] The above description is only a part of the embodiments of the present invention and does not limit the scope of protection of the present invention. Any equivalent device or equivalent process transformation made based on the content of the present invention specification and drawings, or direct or indirect application in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A day and night dual-use panoramic fisheye lens, characterized in that, The lens comprises nine lenses, arranged sequentially from the object side to the image side as: first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, and ninth lens; the coating wavelength of the nine lenses is 420-900nm, and the maximum reflectivity is less than 1%. The first lens has negative refractive power, with a convex object side and a concave image side; The second lens has negative refractive power, with a convex object side and a concave image side; The third lens has negative refractive power, with a concave object side and a convex image side; The fourth lens has positive refractive power, with a concave object side and a convex image side; The fifth lens has positive refractive power and a convex object-side surface. The sixth lens has positive refractive power, and the object side and image side are both convex. The seventh lens has negative refractive power, with a concave object side and a convex image side; The eighth lens has positive refractive power, and the object side and image side are both convex. The ninth lens has negative refractive power, with a concave object side and a convex image side; The image-side surface of the third lens and the object-side surface of the fourth lens are glued together. The image-side surface of the sixth lens and the object-side surface of the seventh lens are glued together. The image-side surface of the eighth lens and the object-side surface of the ninth lens are glued together. The lens satisfies the following formula: 1.0 <R1 / R2<6.0 3.1 <R3 / R4<6.9 1.8 <D2 / R2<1.9 1.5 <D4 / R4<1.7 In the formula, R1 and R2 are the curvature radii of the object side and the image side of the first lens, respectively; R3 and R4 are the curvature radii of the object side and the image side of the second lens, respectively; and D2 and D4 are the effective light-transmitting apertures of the image side of the first lens and the image side of the second lens, respectively. The lens satisfies the following formula: 1.4 <BFL / f<1.9 9.0 <TTL / f<13.0 In the formula, BFL is the distance from the vertex of the side of the ninth lens to the imaging plane, and f is the focal length of the lens; The lens satisfies the following formula: 350 <Fno*FOV<370 In the formula, Fno is the F-Number value of the lens, and FOV is the maximum field of view of the lens.

2. The day and night dual-use panoramic fisheye lens as described in claim 1, characterized in that, The lens satisfies the following formula: Nd1>1.85 6.0 <D1 / f<8.7 In the formula, Nd1 is the refractive index parameter of the first lens, D1 is the effective aperture of the front surface of the first lens, and f is the focal length of the lens.

3. The day and night dual-use panoramic fisheye lens as described in claim 1, characterized in that, The lens also includes an aperture stop, which is disposed between the fifth lens and the sixth lens; and... The lens satisfies the following formula: 2.6<CT9+CT 10 <4.0 0 <CT7<0.15 0<CT 13 <0.15 In the formula, CT7 is the air gap between the fourth and fifth lenses, CT9 is the gap between the fifth lens and the aperture stop, and CT... 10 The distance between the aperture stop and the sixth lens, CT 13 This is the air gap between the seventh and eighth lenses.

4. The day and night dual-use panoramic fisheye lens as described in claim 1, characterized in that, The lens satisfies the following formula: 7 <Vd3-Vd4<13 45 <Vd6-Vd7<55 44 <Vd8-Vd9<56 In the formula, Vd3, Vd4, Vd6, Vd7, Vd8, and Vd9 are the Abbe coefficients of the third, fourth, sixth, seventh, eighth, and ninth lenses, respectively.

5. A day / night dual-use panoramic fisheye lens as described in claim 1, characterized in that, The lens satisfies the following formula: 0.63 <PgF1<0.66 0.60 <PgF7<0.66 0.61 <PgF9<0.68 In the formula, PgF1, PgF7, and PgF9 are the dispersion shift coefficients of the first lens, the seventh lens, and the ninth lens, respectively.

6. A day / night dual-use panoramic fisheye lens as described in claim 1, characterized in that, The seventh lens uses glass material with a positive Dn / Dt value, while the sixth and eighth lenses use glass material with a negative Dn / Dt value.

7. A day / night dual-use panoramic fisheye lens as described in claim 1, characterized in that, All of the first to the ninth lenses are spherical mirrors.

Images