Observation and aiming lens

Abstract

The present application discloses an observation and aiming lens. The observation and aiming lens sequentially includes, from the object side to the image side along the optical axis: a first lens with positive optical power, a second lens with positive optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with negative optical power, a sixth lens with positive optical power, a seventh lens with positive optical power, an eighth lens with negative optical power, and a ninth lens with negative optical power; the combined effective focal length Fa of the second lens, the third lens, the fourth lens, and the fifth lens and the effective focal length F of the observation and aiming lens satisfy: -1.50 ≤ Fa / F ≤ -0.30.

Description

Technical Field

[0001] This application relates to the field of optical elements, and more specifically, to a sighting lens. Background Art

[0002] A sighting lens, also known as a telescopic sight and a sniper scope, enables the user to see the target more clearly. Generally speaking, there are mainly the following five technical requirements for sighting lenses: 1) As a handheld product, portability is more emphasized for sighting lenses, and the weight and volume of the lens should be small enough, so there is a requirement for miniaturization of sighting lenses; 2) The usage scenario of sighting lenses is to observe object details, and the object field angle is small, so a longer focal length is required for the lens; 3) To meet the need for discerning tiny details, there are requirements for high image quality and weak ghosting degree for sighting lenses; 4) To meet the needs of night observation, there is a requirement for infrared confocal for sighting lenses; 5) To meet dim fields such as dusk and early morning, it is required that the sighting lens can achieve high resolution in the wide spectrum of 430nm - 940nm, so there is a requirement for wide-spectrum chromatic aberration correction for sighting lenses.

[0003] However, the existing sighting lenses in the prior art still have the following deficiencies: 1) It is difficult for the sighting lenses in the prior art to balance the lens aperture and high image quality; 2) It is difficult for the sighting lenses in the prior art to achieve a balance between long focal length and shorter optical overall length; 3) The usage band of the sighting lenses in the prior art is narrow, and it is difficult to achieve infrared confocal; 4) There is little room for optimizing ghost images in the sighting lenses in the prior art, and it is difficult to balance high image quality; 5) It is difficult for the sighting lenses in the prior art to achieve high resolution in the wide spectrum of 430nm - 940nm. Summary of the Invention

[0004] On the one hand, this application provides a sighting lens, which sequentially includes, along the optical axis from the object side to the image side: a first lens with positive optical power, a second lens with positive optical power, a third lens with negative optical power, a fourth lens with positive optical power, a fifth lens with negative optical power, a sixth lens with positive optical power, a seventh lens with positive optical power, an eighth lens with negative optical power, and a ninth lens with negative optical power; the combined effective focal length Fa of the second lens, the third lens, the fourth lens, and the fifth lens and the effective focal length F of the sighting lens satisfy: -1.50 ≤ Fa / F ≤ -0.30.

[0005] In one embodiment, the object side surface of the first lens is convex; the object side surface of the second lens is convex; the image side surface of the third lens is concave; both the object side surface and the image side surface of the fourth lens are convex; both the object side surface and the image side surface of the fifth lens are concave; the image side surface of the sixth lens is convex; both the object side surface and the image side surface of the seventh lens are convex; both the object side surface and the image side surface of the eighth lens are concave; and the object side surface of the ninth lens is concave.

[0006] In one embodiment, the maximum clear aperture Dmax of the observation and aiming lens and the distance TTL from the object side surface of the first lens to the imaging surface of the observation and aiming lens on the optical axis satisfy: 0.3 ≤ Dmax / TTL ≤ 0.55.

[0007] In one embodiment, the distance TTL from the object side surface of the first lens to the imaging surface of the observation and aiming lens on the optical axis and the effective focal length F of the observation and aiming lens satisfy: 1 ≤ TTL / F ≤ 1.5.

[0008] In one embodiment, the back focal length BFL of the observation and aiming lens and the distance TTL from the object side surface of the first lens to the imaging surface of the observation and aiming lens on the optical axis satisfy: 0.15 ≤ BFL / TTL ≤ 0.4.

[0009] In one embodiment, the observation and aiming lens satisfies: 0.6 ≤ F1 / F ≤ 1.6, where F1 is the effective focal length of the first lens.

[0010] In one embodiment, the observation and aiming lens satisfies: 0.4 ≤ F2 / F ≤ 1.3, where F2 is the effective focal length of the second lens.

[0011] In one embodiment, the observation and aiming lens satisfies: -0.6 ≤ F3 / F ≤ -0.15, where F3 is the effective focal length of the third lens.

[0012] In one embodiment, the observation and aiming lens satisfies: 0.15 ≤ F4 / F ≤ 0.50, where F4 is the effective focal length of the fourth lens.

[0013] In one embodiment, the observation and aiming lens satisfies: -0.35 ≤ F5 / F ≤ -0.20, where F5 is the effective focal length of the fifth lens.

[0014] In one embodiment, the observation and aiming lens satisfies: 0.30 ≤ F6 / F ≤ 0.90, where F6 is the effective focal length of the sixth lens.

[0015] In one embodiment, the observation and aiming lens satisfies: 0.10 ≤ F7 / F ≤ 0.80, where F7 is the effective focal length of the seventh lens.

[0016] In one embodiment, the observation and aiming lens satisfies: -1.0 ≤ F8 / F ≤ -0.15, where F8 is the effective focal length of the eighth lens.

[0017] In one embodiment, the observation and aiming lens satisfies: -1 ≤ F9 / F ≤ -0.20, where F9 is the effective focal length of the ninth lens.

[0018] In one embodiment, the observation and aiming lens satisfies: 0.8 ≤ Fb / F ≤ 10.5, where Fb is the combined effective focal length of the seventh lens and the eighth lens.

[0019] In one embodiment, the observation and aiming lens satisfies: 0.4 ≤ F18 / F ≤ 1.0, where F18 is the combined effective focal length of the first lens to the eighth lens.

[0020] In one embodiment, the observation and aiming lens satisfies: -1.5 ≤ F18 / F9 ≤ -0.6, where Fb is the combined effective focal length of the seventh lens and the eighth lens, F18 is the combined effective focal length of the first lens to the eighth lens, and F9 is the effective focal length of the ninth lens.

[0021] In one embodiment, the observation and aiming lens satisfies at least one of the following: 1.7 ≤ ND1 ≤ 2.2, 45 ≤ VD2 ≤ 100, 45 ≤ VD4 ≤ 100, where ND1 is the refractive index of the first lens, VD2 is the Abbe number of the second lens, and VD4 is the Abbe number of the fourth lens.

[0022] In one embodiment, the observation and aiming lens satisfies at least one of the following: 0.40 ≤ Dmax / TTL ≤ 0.5, 1.05 ≤ TTL / F ≤ 1.25, 0.18 ≤ BFL / TTL ≤ 0.32, 0.8 ≤ F1 / F ≤ 1.4, 0.6 ≤ F2 / F ≤ 1, -0.5 ≤ F3 / F ≤ -0.2, 0.2 ≤ F4 / F ≤ 0.4, -0.3 ≤ F5 / F ≤ -0.25, 0.4 ≤ F6 / F ≤ 0.75, 0.2 ≤ F7 / F ≤ 0.62, -0.9 ≤ F8 / F ≤ -0.2, -0.85 ≤ F9 / F ≤ -0.45, -1.22 ≤ Fa / F ≤ -0.5, 1 ≤ Fb / F ≤ 10.2, 0.6 ≤ F18 / F ≤ 0.75, -1.3 ≤ F18 / F9 ≤ -0.8, 1.8 ≤ ND1 ≤ 2.2, 60 ≤ VD2 ≤ 100, 60 ≤ VD4 ≤ 100, where Dmax is the maximum clear aperture of the observation and aiming lens, TTL is the distance on the optical axis from the object side of the first lens to the imaging surface of the observation and aiming lens, BFL is the back focal length of the observation and aiming lens, F1 is the effective focal length of the first lens, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, F4 is the effective focal length of the fourth lens, F5 is the effective focal length of the fifth lens, F6 is the effective focal length of the sixth lens, F7 is the effective focal length of the seventh lens, F8 is the effective focal length of the eighth lens, F9 is the effective focal length of the ninth lens, Fb is the combined effective focal length of the seventh lens and the eighth lens, F18 is the combined effective focal length of the first lens to the eighth lens, ND1 is the refractive index of the first lens, VD2 is the Abbe number of the second lens, and VD4 is the Abbe number of the fourth lens.

[0023] On the other hand, this application provides an electronic device. The electronic device includes the observation and aiming lens provided by this application and an imaging element for converting the optical image formed by the observation and aiming lens into an electrical signal.

[0024] The observation and aiming lens provided by this application uses nine lenses. By reasonably setting the optical power of each lens and reasonably distributing the combined effective focal lengths of the second, third, fourth, and fifth lenses, it is beneficial to achieve apochromatism in a wide spectrum and infrared confocal. The observation and aiming lens provided by this application has at least one beneficial effect such as miniaturization, high resolution, low ghost image, and infrared confocal. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, objectives, and advantages of this application will become more apparent by reading the detailed description of the non-restrictive embodiments with reference to the following drawings:

[0026] Figure 1 Schematic structural diagram of the observation and aiming lens according to Embodiment 1 of this application;

[0027] Figure 2 Relative illuminance curve diagram of the observation and aiming lens according to Embodiment 1 of this application;

[0028] Figure 3 Ray Fan diagram of the observation and aiming lens according to Embodiment 1 of this application;

[0029] Figure 4 Schematic structural diagram of the observation and aiming lens according to Embodiment 2 of this application;

[0030] Figure 5 Relative illuminance curve diagram of the observation and aiming lens according to Embodiment 2 of this application;

[0031] Figure 6 Ray Fan diagram of the observation and aiming lens according to Embodiment 2 of this application;

[0032] Figure 7 Schematic structural diagram of the observation and aiming lens according to Embodiment 3 of this application;

[0033] Figure 8 Relative illuminance curve diagram of the observation and aiming lens according to Embodiment 3 of this application;

[0034] Figure 9 Ray Fan diagram of the observation and aiming lens according to Embodiment 3 of this application;

[0035] Figure 10 Schematic structural diagram of the observation and aiming lens according to Embodiment 4 of this application;

[0036] Figure 11 Relative illuminance curve diagram of the observation and aiming lens according to Embodiment 4 of this application;

[0037] Figure 12 Ray Fan diagram of the observation and aiming lens according to Embodiment 4 of this application;

[0038] Figure 13 It is a schematic structural diagram of the observation and aiming lens according to Embodiment 5 of the present application;

[0039] Figure 14 It is a relative illumination curve graph of the observation and aiming lens according to Embodiment 5 of the present application;

[0040] Figure 15 It is a Ray Fan diagram of the observation and aiming lens according to Embodiment 5 of the present application;

[0041] Figure 16 It is a schematic structural diagram of the observation and aiming lens according to Embodiment 6 of the present application;

[0042] Figure 17 It is a relative illumination curve graph of the observation and aiming lens according to Embodiment 6 of the present application;

[0043] Figure 18 It is a Ray Fan diagram of the observation and aiming lens according to Embodiment 6 of the present application. Detailed implementation manners

[0044] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. It should be understood that these detailed descriptions are only descriptions of the exemplary embodiments of the present application, and do not limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] It should be noted that in this specification, the expressions such as first, second, and third are only used to distinguish one feature from another feature, and do not represent any limitation on the feature. Therefore, without departing from the teachings of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0046] In the drawings, for the sake of convenience of illustration, the thickness, size, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0047] In this text, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The judgment of the surface shape in the paraxial region can be made according to the general methods in the art. For example, the concavity and convexity can be judged by the positive or negative value of the R value (R refers to the radius of curvature in the paraxial region). In this text, the surface of each lens closest to the object to be photographed is called the object side surface of the lens, and the surface of each lens closest to the imaging side is called the image side surface of the lens. For the object side surface, when the R value is positive, it is judged to be convex, and when the R value is negative, it is judged to be concave; for the image side surface, when the R value is positive, it is judged to be concave, and when the R value is negative, it is judged to be convex.

[0048] It should also be understood that the terms "comprises", "comprising", "has", "including" and / or "including having", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when an expression such as "at least one of..." appears after a list of listed features, it modifies the entire list of listed features rather than an individual element in the list. In addition, when describing the embodiments of the present application, the use of "may" means "one or more embodiments of the present application". And the term "exemplary" is intended to refer to an example or illustration.

[0049] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in a common dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formalized sense unless expressly so defined herein.

[0050] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Hereinafter, the features, principles and other aspects of the present application will be described in detail with reference to the drawings and in combination with the embodiments.

[0051] In an exemplary embodiment, the sighting lens provided by the present application may include, for example, nine lenses having optical power, namely, 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. These nine lenses are arranged in sequence along the optical axis from the object side to the image side.

[0052] In an exemplary embodiment, the sighting lens may further include a photosensitive element disposed on the image side of the ninth lens. Optionally, the photosensitive element disposed on the image side of the ninth lens may be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor device (CMOS).

[0053] In an exemplary embodiment, the sighting lens may further include a diaphragm for restricting the light beam to further improve the imaging quality of the sighting lens. Exemplarily, the diaphragm may be disposed between the first lens and the second lens. The diaphragm is beneficial for converging the light entering the sighting lens, effectively controlling the light passing amount, and at the same time can also shorten the total length of the sighting lens, which is beneficial for realizing miniaturization while improving the imaging quality of the sighting lens. However, it should be noted that the position of the diaphragm disclosed here is only an example and not a limitation; in an alternative embodiment, the diaphragm may also be disposed at other positions according to actual needs.

[0054] In an exemplary embodiment, the first lens may have a positive optical power, its object side is convex, and its image side is concave or flat. The optical power of the first lens is positive, undertaking the main optical power of the system. By collecting light through the first lens, the light emitted from the first lens approaches the optical axis direction, reducing the aperture of the rear lenses, which is beneficial for realizing miniaturization. The image side of the first lens is flat or concave, which is beneficial for reducing the incident angle of the on-axis light on the image side of the first lens, reducing the spherical aberration generated on the image side of the first lens, and is beneficial for realizing high image quality; the first lens may select a material with a relatively large refractive index to reduce the surface curvature and reduce the generation of aberration, which is beneficial for realizing high image quality; the first lens may also select a material with a positive and relatively large abnormal dispersion, which is beneficial for realizing apochromatism in a wide spectrum and realizing infrared confocal.

[0055] In an exemplary embodiment, the second lens may have a positive optical power, its object side is convex, and its image side is convex or concave. When the object side of the second lens is convex and the image side is concave, the second lens is in a meniscus shape, which is beneficial for reducing the incident angle of the on-axis light on the image side of the second lens, reducing the spherical aberration generated on the image side of the second lens, and is beneficial for realizing high image quality; when both the object side and the image side of the second lens are convex, the object side and the image side jointly share the optical power, reducing the surface curvature and reducing the generation of aberration, which is beneficial for realizing high image quality; the second lens may be paired with a low-dispersion material to reduce the generation of chromatic aberration and reduce the system correction difficulty, which is beneficial for realizing high image quality; the second lens may also select a material with a positive and relatively large abnormal dispersion, which is beneficial for realizing apochromatism in a wide spectrum and realizing infrared confocal; optionally, the second lens, the third lens, the fourth lens, and the fifth lens may form a four-cemented lens group. The second lens has a positive optical power in the four-cemented lens group, and is paired with the third lens, the fourth lens, and the fifth lens to realize the correction of apochromatism and spherical aberration, which is beneficial for realizing high image quality.

[0056] In an exemplary embodiment, the third lens may have a negative focal power. Its object side is convex or concave, and its image side is concave. The concave image side of the third lens can introduce negative spherical aberration to balance the positive spherical aberration generated by the first lens, which is beneficial to achieving high image quality. When both the object side and the image side of the third lens are concave, they jointly share the focal power, reducing the surface curvature and the generation of aberration, which is beneficial to achieving high image quality. When the object side of the third lens is convex and the image side is concave, it is beneficial to reduce the incident angle of the on-axis light rays, reduce the generation of spherical aberration, and at the same time is beneficial to reducing the tolerance sensitivity. The third lens can select a material with negative and relatively small anomalous dispersion, which is beneficial to achieving apochromatism in a wide spectrum and realizing infrared confocal. Optionally, the second lens, the third lens, the fourth lens, and the fifth lens can form a four-cemented lens group. The third lens has a negative focal power in the four-cemented lens group, and together with the second lens, the fourth lens, and the fifth lens, it realizes the correction of apochromatism and spherical aberration, which is beneficial to achieving high image quality.

[0057] In an exemplary embodiment, the fourth lens may have a positive focal power. Its object side is convex, and its image side is convex. Both the object side and the image side of the fourth lens are convex, jointly sharing the focal power, reducing the surface curvature, and reducing the generation of aberration, which is beneficial to achieving high image quality. The convex object side of the fourth lens can reduce the incident angle of the on-axis light rays and reduce the generation of spherical aberration, which is beneficial to achieving high image quality. The fourth lens can select a material with positive and relatively large anomalous dispersion, which is beneficial to achieving apochromatism in a wide spectrum and realizing infrared confocal. Optionally, the second lens, the third lens, the fourth lens, and the fifth lens can form a four-cemented lens group. The fourth lens has a positive focal power in the four-cemented lens group, and together with the second lens, the third lens, and the fifth lens, it realizes the correction of apochromatism and spherical aberration, which is beneficial to achieving high image quality.

[0058] In an exemplary embodiment, the fifth lens may have a negative focal power. Both its object side and its image side are concave. Both the object side and the image side of the fifth lens are concave, jointly sharing the focal power, reducing the surface curvature, and reducing the generation of aberration, which is beneficial to achieving high image quality. Optionally, the second lens, the third lens, the fourth lens, and the fifth lens can form a four-cemented lens group. The fifth lens has a negative focal power in the four-cemented lens group, and together with the second lens, the third lens, and the fourth lens, it realizes the correction of apochromatism and spherical aberration, which is beneficial to achieving high image quality.

[0059] In an exemplary embodiment, the sixth lens may have a positive optical power. Its object side may be convex, planar, or concave, and its image side is convex. Both the object side and the image side of the sixth lens are convex, sharing the optical power together, reducing the surface curvature, and reducing the generation of aberrations, which is beneficial to achieving high image quality. When the object side of the sixth lens is planar or concave, the focusing ability of the surface on light is reduced, and it may even have a diverging ability for light, which is beneficial to improving the ghost images generated by this surface and the protective glass (disposed between the ninth lens and the imaging surface), diverging the ghost image energy, and ensuring clear image quality on the image plane. The sixth lens can select a material with a relatively large refractive index, reduce the surface curvature, and reduce the generation of aberrations, which is beneficial to achieving high image quality. Since the optical power of the sixth lens is positive, axial chromatic aberration will be introduced. The sixth lens, in cooperation with the second lens, the third lens, the fourth lens, and the fifth lens, can balance the axial chromatic aberration of the system, which is beneficial to achieving high resolution for mixed light in the wide spectrum of 430 nm to 940 nm.

[0060] In an exemplary embodiment, the seventh lens may have a positive optical power. Its object side is convex, and its image side is convex. Both the object side and the image side of the seventh lens are convex, sharing the optical power together, reducing the surface curvature, and reducing the generation of aberrations, which is beneficial to achieving high image quality. Optionally, the seventh lens and the eighth lens may form a doublet lens group. The seventh lens has a positive optical power in the doublet lens group and, in cooperation with the eighth lens, achieves apochromatism, which is beneficial to achieving high image quality.

[0061] In an exemplary embodiment, the eighth lens may have a negative optical power. Both its object side and its image side are concave. Both the object side and the image side of the eighth lens are concave, sharing the optical power together, reducing the surface curvature, and reducing the generation of aberrations, which is beneficial to achieving high image quality. Optionally, the seventh lens and the eighth lens may form a doublet lens group. The eighth lens has a negative optical power in the doublet lens group and, in cooperation with the seventh lens, achieves apochromatism, which is beneficial to achieving high image quality.

[0062] In an exemplary embodiment, the ninth lens may have a negative optical power, with its object side being concave and its image side being convex or concave. When the object side of the ninth lens is concave and the image side is convex, the ninth lens has a meniscus shape, which is beneficial for correcting off-axis aberrations such as field curvature and astigmatism of the system, and achieving high resolution at a wide object distance from 1.5 m to infinity. At the same time, since the image side of the ninth lens is convex, it has a diverging ability for light, which is beneficial for improving the ghosting generated by this surface and the protective glass (disposed between the ninth lens and the imaging surface), diverging the ghost energy, and ensuring clear image quality on the image plane. When both the object side and the image side of the ninth lens are concave, they share the optical power together, reducing the surface curvature and the generation of aberrations, which is beneficial for achieving high image quality. The ninth lens has a negative optical power and is combined with the first to eighth lenses with positive optical powers to form a telephoto structure, reducing the overall optical length and being beneficial for miniaturization. The ninth lens can select a material with a relatively large refractive index, reducing the surface curvature and the generation of aberrations, which is beneficial for achieving high image quality.

[0063] In an exemplary embodiment, the second, third, fourth, and fifth lenses may form a four-cemented lens group. The second lens has a positive optical power, the third lens has a negative optical power, the fourth lens has a positive optical power, and the fifth lens has a negative optical power. Among them, the second and fourth lenses with positive optical powers can select materials with a relatively large Abbe number, which is beneficial for reducing the generation of chromatic aberration and achieving high image quality. Further, materials with large anomalous dispersion can be selected, which is beneficial for correcting chromatic aberration and achieving infrared defocus. Optionally, the curvatures of the object side of the second lens and the image side of the fifth lens are similar, and the overall four-cemented lens group has a meniscus shape, which is beneficial for reducing the generation of spherical aberration.

[0064] In an exemplary embodiment, the seventh and eighth lenses may form a doublet lens group. The seventh lens has a positive optical power, and the eighth lens has a negative optical power. The curvatures of the object side of the seventh lens and the image side of the eighth lens are similar, and the overall doublet lens group formed by the seventh and eighth lenses has a meniscus shape, which is beneficial for reducing the generation of spherical aberration.

[0065] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: -1.50 ≤ Fa / F ≤ -0.30, where Fa is the combined effective focal length of the second, third, fourth, and fifth lenses, and F is the effective focal length of the observation and aiming lens. More specifically, Fa and F may further satisfy -1.22 ≤ Fa / F ≤ -0.5. Satisfying -1.50 ≤ Fa / F ≤ -0.30, by reasonably distributing the combined effective focal length of the second, third, fourth, and fifth lenses, it is beneficial for achieving apochromatism in a wide spectrum and infrared confocal.

[0066] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.3 ≤ Dmax / TTL ≤ 0.55, where Dmax is the maximum clear aperture of the sighting lens, and TTL is the distance from the object side surface of the first lens to the imaging surface of the sighting lens on the optical axis. More specifically, Dmax and TTL may further satisfy 0.40 ≤ Dmax / TTL ≤ 0.5. Satisfying 0.3 ≤ Dmax / TTL ≤ 0.55, when the total optical length of the system is certain, by controlling the maximum clear aperture of the system, the maximum clear aperture of the system is relatively small, which is beneficial to realizing miniaturization.

[0067] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 1 ≤ TTL / F ≤ 1.5, where TTL is the distance from the object side surface of the first lens to the imaging surface of the sighting lens on the optical axis, and F is the effective focal length of the sighting lens. More specifically, TTL and F may further satisfy 1.05 ≤ TTL / F ≤ 1.25. Satisfying 1 ≤ TTL / F ≤ 1.5, when the focal length value of the system is certain, by controlling the total optical length of the system, the total optical length of the system is relatively small, which is beneficial to realizing miniaturization.

[0068] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.15 ≤ BFL / TTL ≤ 0.4, where BFL is the back focal length of the sighting lens (i.e., the distance from the image side surface of the ninth lens to the imaging surface of the sighting lens on the optical axis), and TTL is the distance from the object side surface of the first lens to the imaging surface of the sighting lens on the optical axis. More specifically, BFL and TTL may further satisfy 0.18 ≤ BFL / TTL ≤ 0.32. Satisfying 0.15 ≤ BFL / TTL ≤ 0.4, on the basis of realizing miniaturization, by controlling the optical back focal length of the system, it is beneficial to accommodate cameras with different interfaces and improve the versatility of the lens.

[0069] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.6 ≤ F1 / F ≤ 1.6, where F1 is the effective focal length of the first lens, and F is the effective focal length of the sighting lens. More specifically, F1 and F may further satisfy 0.8 ≤ F1 / F ≤ 1.4. Satisfying 0.6 ≤ F1 / F ≤ 1.6, by reasonably distributing the focal length value of the first lens and collecting light through the first lens, the light rays emitted by the first lens approach the optical axis direction, which is beneficial to reducing the aperture of the rear lenses and realizing miniaturization.

[0070] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.4 ≤ F2 / F ≤ 1.3, where F2 is the effective focal length of the second lens and F is the effective focal length of the sighting lens. More specifically, F2 and F may further satisfy 0.6 ≤ F2 / F ≤ 1. Satisfying 0.4 ≤ F2 / F ≤ 1.3, by reasonably allocating the focal length value of the second lens, the second lens has a positive optical power in the four-cemented lens group composed of the second lens, the third lens, the fourth lens, and the fifth lens, achieving apochromatism, which is beneficial to achieving high image quality.

[0071] In an exemplary embodiment, the sighting lens according to the present application may satisfy: -0.6 ≤ F3 / F ≤ -0.15, where F3 is the effective focal length of the third lens and F is the effective focal length of the sighting lens. More specifically, F3 and F may further satisfy -0.5 ≤ F3 / F ≤ -0.2. Satisfying -0.6 ≤ F3 / F ≤ -0.15, by reasonably allocating the focal length value of the third lens, the third lens has a negative optical power in the four-cemented lens group composed of the second lens, the third lens, the fourth lens, and the fifth lens, achieving apochromatism, which is beneficial to achieving high image quality.

[0072] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.15 ≤ F4 / F ≤ 0.50, where F4 is the effective focal length of the fourth lens and F is the effective focal length of the sighting lens. More specifically, F4 and F may further satisfy 0.2 ≤ F4 / F ≤ 0.4. Satisfying 0.15 ≤ F4 / F ≤ 0.50, by reasonably allocating the focal length value of the fourth lens, the fourth lens has a positive optical power in the four-cemented lens group composed of the second lens, the third lens, the fourth lens, and the fifth lens, achieving apochromatism, which is beneficial to achieving high image quality.

[0073] In an exemplary embodiment, the sighting lens according to the present application may satisfy: -0.35 ≤ F5 / F ≤ -0.20, where F5 is the effective focal length of the fifth lens and F is the effective focal length of the sighting lens. More specifically, F5 and F may further satisfy -0.3 ≤ F5 / F ≤ -0.25. Satisfying -0.35 ≤ F5 / F ≤ -0.20, by reasonably allocating the focal length value of the fifth lens, the fifth lens has a negative optical power in the four-cemented lens group composed of the second lens, the third lens, the fourth lens, and the fifth lens, achieving apochromatism, which is beneficial to achieving high image quality.

[0074] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.30 ≤ F6 / F ≤ 0.90, where F6 is the effective focal length of the sixth lens and F is the effective focal length of the sighting lens. More specifically, F6 and F may further satisfy 0.4 ≤ F6 / F ≤ 0.75. Satisfying 0.30 ≤ F6 / F ≤ 0.90, by reasonably allocating the focal length value of the sixth lens, the sixth lens has a positive optical power, and together with the fifth lens, apochromatism is achieved, which is beneficial to achieving high image quality.

[0075] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.10 ≤ F7 / F ≤ 0.80, where F7 is the effective focal length of the seventh lens and F is the effective focal length of the sighting lens. More specifically, F7 and F may further satisfy 0.2 ≤ F7 / F ≤ 0.62. Satisfying 0.10 ≤ F7 / F ≤ 0.80, by reasonably allocating the focal length value of the seventh lens, the seventh lens has a positive optical power in the doublet lens group composed of the seventh lens and the eighth lens, correcting the remaining off-axis chromatic aberration, which is beneficial to achieving high image quality.

[0076] In an exemplary embodiment, the sighting lens according to the present application may satisfy: -1.0 ≤ F8 / F ≤ -0.15, where F8 is the effective focal length of the eighth lens and F is the effective focal length of the sighting lens. More specifically, F8 and F may further satisfy -0.9 ≤ F8 / F ≤ -0.2. Satisfying -1.0 ≤ F8 / F ≤ -0.15, by reasonably allocating the focal length value of the eighth lens, the eighth lens has a negative optical power in the doublet lens group composed of the seventh lens and the eighth lens, correcting the remaining off-axis chromatic aberration, which is beneficial to achieving high image quality.

[0077] In an exemplary embodiment, the sighting lens according to the present application may satisfy: -1 ≤ F9 / F ≤ -0.20, where F9 is the effective focal length of the ninth lens and F is the effective focal length of the sighting lens. More specifically, F9 and F may further satisfy -0.85 ≤ F9 / F ≤ -0.45. Satisfying -1 ≤ F9 / F ≤ -0.20, by reasonably allocating the focal length value of the ninth lens, the ninth lens has a negative optical power, and when paired with the first to eighth lenses having positive optical powers, a telephoto architecture is formed, reducing the overall optical length, which is beneficial to achieving miniaturization.

[0078] In an exemplary embodiment, the sighting lens according to the present application may satisfy: 0.8 ≤ Fb / F ≤ 10.5, where Fb is the combined effective focal length of the seventh lens and the eighth lens, and F is the effective focal length of the sighting lens. More specifically, Fb and F may further satisfy 1 ≤ Fb / F ≤ 10.2. Satisfying 0.8 ≤ Fb / F ≤ 10.5, by reasonably allocating the focal length value of the doublet lens group composed of the seventh lens and the eighth lens, it is beneficial to correct the remaining off-axis chromatic aberration and achieve infrared confocal.

[0079] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: 0.4 ≤ F18 / F ≤ 1.0, where F18 is the combined effective focal length of the first lens to the eighth lens, and F is the effective focal length of the observation and aiming lens. More specifically, F18 and F may further satisfy 0.6 ≤ F18 / F ≤ 0.75. Satisfying 0.4 ≤ F18 / F ≤ 1.0, by reasonably distributing the combined effective focal length of the first lens to the eighth lens, and forming a telephoto structure with the ninth lens, it is beneficial to reduce the overall optical length and achieve miniaturization.

[0080] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: -1.5 ≤ F18 / F9 ≤ -0.6. Where F18 is the combined effective focal length of the first lens to the eighth lens, and F9 is the effective focal length of the ninth lens. More specifically, F18 and F9 may further satisfy -1.3 ≤ F18 / F9 ≤ -0.8. Satisfying -1.5 ≤ F18 / F9 ≤ -0.6, by reasonably distributing the combined effective focal length of the first lens to the eighth lens and the focal length value of the ninth lens, and forming a telephoto structure, it is beneficial to reduce the overall optical length and achieve miniaturization.

[0081] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: 1.7 ≤ ND1 ≤ 2.2, where ND1 is the refractive index of the first lens. More specifically, ND1 may further satisfy 1.8 ≤ ND1 ≤ 2.2. Satisfying 1.7 ≤ ND1 ≤ 2.2, by reasonably setting the refractive index of the first lens, reducing the generation of chromatic aberration, and reducing the difficulty of chromatic aberration correction of the system, it is beneficial to achieve infrared confocal.

[0082] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: 45 ≤ VD2 ≤ 100, where VD2 is the Abbe number of the second lens. More specifically, VD2 may further satisfy 60 ≤ VD2 ≤ 100. Satisfying 45 ≤ VD2 ≤ 100, by reasonably setting the Abbe number of the second lens, reducing the generation of chromatic aberration, and reducing the difficulty of chromatic aberration correction of the system, it is beneficial to achieve infrared confocal.

[0083] In an exemplary embodiment, the observation and aiming lens according to the present application may satisfy: 45 ≤ VD4 ≤ 100, where VD4 is the Abbe number of the fourth lens. More specifically, VD4 may further satisfy 60 ≤ VD4 ≤ 100. Satisfying 45 ≤ VD4 ≤ 100, by reasonably setting the Abbe number of the fourth lens, reducing the generation of chromatic aberration, and reducing the difficulty of chromatic aberration correction of the system, it is beneficial to achieve infrared confocal.

[0084] In an exemplary embodiment, the f-number FNO of the observation and aiming lens according to the present application satisfies: 1.6 ≤ FNO ≤ 3.0. By controlling the size of the entrance pupil diameter of the system, the system has a smaller f-number value, which is beneficial to achieve a large aperture.

[0085] In an exemplary embodiment, the effective focal length F of the sighting lens according to the present application may be in the range of 35 mm to 45 mm. For example, F is 40 mm.

[0086] In an exemplary embodiment, as needed, the sighting lens of the present application may further include a filter and / or a protective glass disposed between the ninth lens and the imaging surface. The filter can filter light rays with different wavelengths, and the protective glass can prevent damage to the image-side elements (e.g., chips) of the sighting lens.

[0087] In an exemplary embodiment, each lens of the sighting lens of the present application may be a spherical lens or an aspherical lens. As needed, the present application does not specifically limit the specific number of spherical lenses and aspherical lenses. When focusing on reflecting the imaging quality, the number of aspherical lenses can be increased, and even all lenses can be aspherical lenses. The characteristic of an aspherical lens is that the curvature continuously changes from the center to the periphery of the lens. Different from a spherical lens with a constant curvature from the center to the periphery, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality of the lens. Exemplarily, the first lens to the ninth lens in the disclosure of the present application are all spherical lenses.

[0088] Those skilled in the art should understand that the refractive index temperature coefficient dn / dt and abnormal dispersion of plastics are relatively large. Reasonably matching an appropriate amount of plastic materials is beneficial to high and low temperature balance and infrared confocal, but too many plastic lenses are not conducive to system stability. The optical lens made of glass can suppress the shift of the back focal length of the optical lens with temperature change to improve system stability; at the same time, using glass materials can avoid the imaging blur of the lens caused by the high and low temperature changes in the use environment, which affects the normal use of the lens. For example, the optical lens with a full glass design has a wide temperature range and can maintain stable optical performance in the range of -40°C to 85°C. In addition, using glass materials can also better correct the chromatic aberration of the system, improve the resolution of the lens, and at the same time reduce the generation of ghost images.

[0089] The present application does not specifically limit the material of the lens. When focusing on the resolution quality and reliability, the first lens to the ninth lens may all be made of glass materials. Of course, in application scenarios with lower temperature stability requirements, the first lens to the ninth lens in the optical lens may also all be made of plastic. Making the optical lens with plastic can effectively reduce the manufacturing cost. Of course, the first lens to the ninth lens in the optical lens may also be made of a combination of plastic and glass.

[0090] The sighting lens according to the above embodiments of the present application may employ multiple lenses, such as the nine lenses described above. By reasonably allocating optical parameters such as the optical power and surface shape of each lens, at least one beneficial effect such as miniaturization, high resolution, low ghost image, and infrared confocal can be achieved.

[0091] However, those skilled in the art should understand that without departing from the technical solutions claimed in the present application, the number of lenses constituting the lens can be changed to obtain the various results and advantages described in this specification. For example, although the nine-lens example is described in the embodiments, the sighting lens is not limited to including nine lenses. If necessary, the sighting lens may also include other numbers of lenses. The specific embodiments of the sighting lens applicable to the above embodiments will be further described below with reference to the accompanying drawings. Embodiment 1

[0092] The following refers to Figure 1 The sighting lens according to Embodiment 1 of the present application is described. Figure 1 The structural schematic diagram of the sighting lens according to Embodiment 1 of the present application is shown.

[0093] As Figure 1 shown, the sighting lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 from the object side to the image side along the optical axis.

[0094] The first lens L1 has a positive optical power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface.

[0095] The second lens L2 has a positive optical power, its object side surface S4 is a convex surface, and its image side surface S5 is a concave surface.

[0096] The third lens L3 has a negative optical power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface.

[0097] The fourth lens L4 has a positive optical power, its object side surface S6 is a convex surface, and its image side surface S7 is a convex surface.

[0098] The fifth lens L5 has a negative optical power, its object side surface S7 is a concave surface, and its image side surface S8 is a concave surface.

[0099] The sixth lens L6 has a positive optical power, its object side surface S9 is a flat surface, and its image side surface S10 is a convex surface.

[0100] The seventh lens L7 has a positive optical power, its object side surface S11 is a convex surface, and its image side surface S12 is a convex surface.

[0101] The eighth lens L8 has a negative optical power, its object side surface S12 is a concave surface, and its image side surface S13 is a concave surface.

[0102] The ninth lens L9 has a negative focal power, its object side S14 is concave, and its image side S15 is concave.

[0103] The second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a doublet lens group.

[0104] The sighting lens may further include a stop STO, and the stop STO can be disposed between the first lens L1 and the second lens L2. Optionally, the sighting lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side S16 and an image side S17. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensing chip located at the imaging surface IMA. The light from the object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0105] Table 1 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens of the sighting lens of Example 1, where the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0106] Table 1

[0107]

[0108] Figure 2 Shows the relative illumination curve of the sighting lens of Example 1, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 3 Shows the Ray Fan diagram of the sighting lens of Example 1, which represents the aberrations corresponding to different fields of view. According to Figure 2 and Figure 3 It can be known that the sighting lens given in Example 1 has the characteristics of high illumination and low aberration, and can achieve good imaging quality. Example 2

[0109] The following refers to Figure 4 to describe the sighting lens according to Embodiment 2 of the present application. Figure 4 Shows a schematic structural diagram of the sighting lens according to Embodiment 2 of the present application.

[0110] As Figure 4 shown, the sighting lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 along the optical axis from the object side to the image side.

[0111] The first lens L1 has a positive focal power, its object side S1 is convex, and its image side S2 is flat.

[0112] The second lens L2 has a positive focal power, with its object side S4 being convex and its image side S5 being concave.

[0113] The third lens L3 has a negative focal power, with its object side S5 being convex and its image side S6 being concave.

[0114] The fourth lens L4 has a positive focal power, with its object side S6 being convex and its image side S7 being convex.

[0115] The fifth lens L5 has a negative focal power, with its object side S7 being concave and its image side S8 being concave.

[0116] The sixth lens L6 has a positive focal power, with its object side S9 being planar and its image side S10 being convex.

[0117] The seventh lens L7 has a positive focal power, with its object side S11 being convex and its image side S12 being convex.

[0118] The eighth lens L8 has a negative focal power, with its object side S12 being concave and its image side S13 being concave.

[0119] The ninth lens L9 has a negative focal power, with its object side S14 being concave and its image side S15 being convex.

[0120] The second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a doublet lens group.

[0121] The sighting lens may further include a stop STO, and the stop STO can be disposed between the first lens L1 and the second lens L2. Optionally, the sighting lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side S16 and an image side S17. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensing chip located at the imaging surface IMA. The light from the object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0122] Table 2 shows the radius of curvature, thickness / distance, refractive index and Abbe number of each lens of the sighting lens of Embodiment 2, wherein the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0123] Table 2

[0124]

[0125] Figure 5 Shows the relative illumination curve of the sighting lens of Embodiment 2, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 6The Ray Fan diagram of the observation and aiming lens of Embodiment 2 is shown, which represents the aberrations corresponding to different fields of view. According to Figure 5 and Figure 6 it can be known that the observation and aiming lens given in Embodiment 2 has the characteristics of high illuminance and low aberration, and can achieve good imaging quality. Embodiment 3

[0126] The following describes the observation and aiming lens according to Embodiment 3 of the present application with reference to Figure 7 The structural schematic diagram of the observation and aiming lens according to Embodiment 3 of the present application is shown. Figure 7 As

[0127] shown, the observation and aiming lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 from the object side to the image side along the optical axis. Figure 7

[0128] The first lens L1 has a positive optical power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface.

[0129] The second lens L2 has a positive optical power, its object side surface S4 is a convex surface, and its image side surface S5 is a concave surface.

[0130] The third lens L3 has a negative optical power, its object side surface S5 is a convex surface, and its image side surface S6 is a concave surface.

[0131] The fourth lens L4 has a positive optical power, its object side surface S6 is a convex surface, and its image side surface S7 is a convex surface.

[0132] The fifth lens L5 has a negative optical power, its object side surface S7 is a concave surface, and its image side surface S8 is a concave surface.

[0133] The sixth lens L6 has a positive optical power, its object side surface S9 is a plane, and its image side surface S10 is a convex surface.

[0134] The seventh lens L7 has a positive optical power, its object side surface S11 is a convex surface, and its image side surface S12 is a convex surface.

[0135] The eighth lens L8 has a negative optical power, its object side surface S12 is a concave surface, and its image side surface S13 is a concave surface.

[0136] The ninth lens L9 has a negative optical power, its object side surface S14 is a concave surface, and its image side surface S15 is a concave surface.

[0137] The second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a double-cemented lens group.

[0138] ​The observation and aiming lens may further include a diaphragm STO, and the diaphragm STO may be disposed between the first lens L1 and the second lens L2. Optionally, the observation and aiming lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side S16 and an image side S17. The filter may be used to correct color deviation, and the protective glass CG may be used to protect the image sensing chip located at the imaging surface IMA. Light from an object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0139] Table 3 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens of the observation and aiming lens of Embodiment 3, where the units of the radius of curvature and thickness / distance are both millimeters (mm).

[0140] Table 3

[0141]

[0142] Figure 8 shows the relative illumination curve of the observation and aiming lens of Embodiment 3, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 9 shows the Ray Fan diagram of the observation and aiming lens of Embodiment 3, which represents the aberration corresponding to different fields of view. According to Figure 8 and Figure 9 it can be known that the observation and aiming lens given in Embodiment 3 has the characteristics of high illumination and low aberration, and can achieve good imaging quality. Embodiment 4

[0143] The following describes the observation and aiming lens according to Embodiment 4 of the present application with reference to Figure 10 The observation and aiming lens according to Embodiment 4 of the present application is described. Figure 10 shows a schematic structural diagram of the observation and aiming lens according to Embodiment 4 of the present application.

[0144] As Figure 10 shown, the observation and aiming lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 along the optical axis from the object side to the image side.

[0145] The first lens L1 has a positive optical power, its object side S1 is a convex surface, and its image side S2 is a concave surface.

[0146] The second lens L2 has a positive optical power, its object side S4 is a convex surface, and its image side S5 is a concave surface.

[0147] The third lens L3 has a negative optical power, its object side S5 is a convex surface, and its image side S6 is a concave surface.

[0148] The fourth lens L4 has a positive optical power, its object side S6 is a convex surface, and its image side S7 is a convex surface.

[0149] The fifth lens L5 has a negative focal power, its object side S7 is concave, and its image side S8 is concave.

[0150] The sixth lens L6 has a positive focal power, its object side S9 is convex, and its image side S10 is convex.

[0151] The seventh lens L7 has a positive focal power, its object side S11 is convex, and its image side S12 is convex.

[0152] The eighth lens L8 has a negative focal power, its object side S12 is concave, and its image side S13 is concave.

[0153] The ninth lens L9 has a negative focal power, its object side S14 is concave, and its image side S15 is concave.

[0154] The second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a doublet lens group.

[0155] The observation and aiming lens may further include a stop STO, and the stop STO can be disposed between the first lens L1 and the second lens L2. Optionally, the observation and aiming lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side S16 and an image side S17. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensing chip located at the imaging surface IMA. The light from the object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0156] Table 4 shows the radius of curvature, thickness / distance, refractive index and Abbe number of each lens of the observation and aiming lens of Embodiment 4, wherein the units of the radius of curvature and the thickness / distance are both millimeters (mm).

[0157] Table 4

[0158]

[0159] Figure 11 Shows the relative illumination curve of the observation and aiming lens of Embodiment 4, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 12 Shows the Ray Fan diagram of the observation and aiming lens of Embodiment 4, which represents the aberration corresponding to different fields of view. According to Figure 11 and Figure 12 It can be seen that the observation and aiming lens given in Embodiment 4 has the characteristics of high illumination and low aberration, and can achieve good imaging quality. Embodiment 5

[0160] The following refers to Figure 13Describes the observation and aiming lens according to Embodiment 5 of the present application. Figure 13 Shows a schematic structural diagram of the observation and aiming lens according to Embodiment 5 of the present application.

[0161] As Figure 13 shown, the observation and aiming lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 along the optical axis from the object side to the image side.

[0162] The first lens L1 has a positive optical power, its object side surface S1 is convex, and its image side surface S2 is concave.

[0163] The second lens L2 has a positive optical power, its object side surface S4 is convex, and its image side surface S5 is convex.

[0164] The third lens L3 has a negative optical power, its object side surface S5 is concave, and its image side surface S6 is concave.

[0165] The fourth lens L4 has a positive optical power, its object side surface S6 is convex, and its image side surface S7 is convex.

[0166] The fifth lens L5 has a negative optical power, its object side surface S7 is concave, and its image side surface S8 is concave.

[0167] The sixth lens L6 has a positive optical power, its object side surface S9 is convex, and its image side surface S10 is convex.

[0168] The seventh lens L7 has a positive optical power, its object side surface S11 is convex, and its image side surface S12 is convex.

[0169] The eighth lens L8 has a negative optical power, its object side surface S12 is concave, and its image side surface S13 is concave.

[0170] The ninth lens L9 has a negative optical power, its object side surface S14 is concave, and its image side surface S15 is concave.

[0171] The second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a doublet lens group.

[0172] The observation and aiming lens may further include a stop STO, and the stop STO may be disposed between the first lens L1 and the second lens L2. Optionally, the observation and aiming lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side surface S16 and an image side surface S17. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensing chip located at the imaging surface IMA. Light from the object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0173] Table 5 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens of the observation and aiming lens of Example 5, where the units of the radius of curvature and thickness / distance are both millimeters (mm).

[0174] Table 5

[0175]

[0176] Figure 14 shows the relative illumination curve of the observation and aiming lens of Example 5, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 15 shows the Ray Fan diagram of the observation and aiming lens of Example 5, which represents the aberration corresponding to different fields of view. According to Figure 14 and Figure 15 it can be known that the observation and aiming lens given in Example 5 has the characteristics of high illumination and low aberration, and can achieve good imaging quality. Example 6

[0177] The following describes the observation and aiming lens according to Embodiment 6 of the present application with reference to Figure 16 Figure Figure 16 shows a schematic structural diagram of the observation and aiming lens according to Embodiment 6 of the present application.

[0178] As Figure 16 shown, the observation and aiming lens sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, and a ninth lens L9 from the object side to the image side along the optical axis.

[0179] The first lens L1 has a positive optical power, its object side surface S1 is a convex surface, and its image side surface S2 is a concave surface.

[0180] The second lens L2 has a positive optical power, its object side surface S4 is a convex surface, and its image side surface S5 is a convex surface.

[0181] The third lens L3 has a negative optical power, its object side surface S5 is a concave surface, and its image side surface S6 is a concave surface.

[0182] The fourth lens L4 has a positive optical power, its object side surface S6 is a convex surface, and its image side surface S7 is a convex surface.

[0183] The fifth lens L5 has a negative optical power, its object side surface S7 is a concave surface, and its image side surface S8 is a concave surface.

[0184] The sixth lens L6 has a positive optical power, its object side surface S9 is a concave surface, and its image side surface S10 is a convex surface.

[0185] The seventh lens L7 has a positive optical power, its object side surface S11 is a convex surface, and its image side surface S12 is a convex surface.

[0186] The eighth lens L8 has a negative focal power, its object side S12 is concave, and its image side S13 is concave.

[0187] The ninth lens L9 has a negative focal power, its object side S14 is concave, and its image side S15 is convex.

[0188] The second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 can form a four-cemented lens group. The seventh lens L7 and the eighth lens L8 can form a doublet lens group.

[0189] The observation and aiming lens may further include a diaphragm STO, and the diaphragm STO can be disposed between the first lens L1 and the second lens L2. Optionally, the observation and aiming lens may further include a filter (not shown) having an object side and an image side and / or a protective glass CG having an object side S16 and an image side S17. The filter can be used to correct color deviation, and the protective glass CG can be used to protect the image sensing chip located at the imaging surface IMA. The light from the object sequentially passes through the surfaces S1 to S17 and finally forms an image on the imaging surface IMA.

[0190] Table 6 shows the radius of curvature, thickness / distance, refractive index, and Abbe number of each lens of the observation and aiming lens of Example 6, where the units of the radius of curvature and thickness / distance are both millimeters (mm).

[0191] Table 6

[0192]

[0193] Figure 17 Shows the relative illumination curve of the observation and aiming lens of Example 6, which represents the relative illumination magnitude values corresponding to different fields of view. Figure 18 Shows the Ray Fan diagram of the observation and aiming lens of Example 6, which represents the aberrations corresponding to different fields of view. According to Figure 17 and Figure 18 It can be known that the observation and aiming lens given in Example 6 has the characteristics of high illumination and low aberration, and can achieve good imaging quality.

[0194] In summary, Examples 1 to 6 respectively satisfy the relationships shown in Table 7 below.

[0195] Table 7

[0196]

[0197] This application also provides an electronic device, which may include an observation and aiming lens according to the above embodiments of this application and an imaging element for converting the optical image formed by the observation and aiming lens into an electrical signal.

[0198] The above description is only a preferred embodiment of the present application and an explanation of the technical principles applied. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solution formed by mutually replacing the above features with the technical features (but not limited to) disclosed in the present application that have similar functions.

Claims

1. A sighting lens, characterized in that: The aiming lens includes, in order from the object side to the image side along the optical axis: a first lens having positive optical power; a second lens having positive optical power; a third lens having negative optical power; a fourth lens having positive refractive power; a fifth lens having negative optical power; a sixth lens element having positive refractive power and having a convex image-side surface; a seventh lens having positive refractive power; an eighth lens having negative optical power; and a ninth lens having negative optical power; The combined effective focal length Fa of the second lens, the third lens, the fourth lens and the fifth lens and the effective focal length F of the aiming lens satisfy the following: -1.50≤Fa / F≤-0.75; The aiming and viewing lens satisfies: 0.30≤F6 / F≤0.55, wherein F6 is the effective focal length of the sixth lens; and The aiming and viewing lens satisfies: -1.21≤F18 / F9≤-1.06, wherein F18 is the combined effective focal length of the first lens to the eighth lens, and F9 is the effective focal length of the ninth lens.

2. The aiming lens according to claim 1, wherein: The object side surface of the first lens is a convex surface; The object side surface of the second lens is a convex surface; The image side surface of the third lens is a concave surface; The object side surface and the image side surface of the fourth lens are both convex surfaces; The object side surface and the image side surface of the fifth lens are both concave surfaces; The object side surface and the image side surface of the seventh lens are both convex surfaces; The object side surface and the image side surface of the eighth lens are both concave surfaces; and The object side surface of the ninth lens is a concave surface.

3. The aiming lens according to claim 1, wherein: The maximum full aperture Dmax of the aiming and viewing lens and the distance TTL from the object side surface of the first lens to the imaging surface of the aiming and viewing lens on the optical axis satisfy: 0.3≤Dmax / TTL≤0.

55.

4. The aiming lens according to claim 1, wherein: A distance TTL from the object side surface of the first lens to the imaging surface of the aiming and viewing lens on the optical axis and an effective focal length F of the aiming and viewing lens satisfy the following conditions: 1≤TTL / F≤1.

5.

5. The aiming lens according to claim 1, wherein: The back focus BFL of the aiming and viewing lens and the distance TTL from the object side surface of the first lens to the imaging surface of the aiming and viewing lens on the optical axis satisfy the following conditions: 0.15≤BFL / TTL≤0.

4.

6. The aiming and viewing lens according to any one of claims 1 to 5, wherein the aiming and viewing lens satisfies: 0.6≤F1 / F≤1.6, wherein: F1 is the effective focal length of the first lens.

7. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: 0.4≤F2 / F≤1.3, wherein: F2 is the effective focal length of the second lens.

8. The aiming and viewing lens according to any one of claims 1 to 5, wherein the aiming and viewing lens satisfies: -0.6≤F3 / F≤-0.15, wherein: F3 is the effective focal length of the third lens.

9. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: 0.15≤F4 / F≤0.50, wherein: F4 is the effective focal length of the fourth lens.

10. The aiming and viewing lens according to any one of claims 1 to 5, wherein the aiming and viewing lens satisfies: -0.35≤F5 / F≤-0.20, wherein: F5 is the effective focal length of the fifth lens.

11. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: 0.10≤F7 / F≤0.80, wherein: F7 is the effective focal length of the seventh lens.

12. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: -1.0≤F8 / F≤-0.15, wherein: F8 is the effective focal length of the eighth lens.

13. The aiming and viewing lens according to any one of claims 1 to 5, wherein the aiming and viewing lens satisfies: -1≤F9 / F≤-0.20, wherein: F9 is the effective focal length of the ninth lens.

14. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: 0.8≤Fb / F≤10.5, wherein: Fb is the combined effective focal length of the seventh lens and the eighth lens.

15. The viewing and aiming lens according to any one of claims 1 to 5, wherein the viewing and aiming lens satisfies: 0.4≤F18 / F≤1.0, wherein: F18 is the combined effective focal length of the first lens to the eighth lens.

16. The aiming and viewing lens according to any one of claims 1 to 5, wherein the aiming and viewing lens satisfies at least one of the following conditions: 1.7≤ND1≤2.2, 45≤VD2≤100, 45≤VD4≤100, in, ND1 is the refractive index of the first lens, VD2 is the Abbe number of the second lens, and VD4 is the Abbe number of the fourth lens.

17. The aiming and viewing lens according to claim 1, wherein the aiming and viewing lens satisfies at least one of the following conditions: 0.40≤Dmax / TTL≤0.5, 1.21≤TTL / F≤1.25, 0.27≤BFL / TTL≤0.32, 0.97≤F1 / F≤1.27, 0.70≤F2 / F≤0.90, -0.40≤F3 / F≤-0.32, 0.30≤F4 / F≤0.34, -0.3≤F5 / F≤-0.25, 0.51≤F6 / F≤0.55, 0.32≤F7 / F≤0.62, -0.84≤F8 / F≤-0.40, -0.60≤F9 / F≤-0.50, -1.07≤Fa / F≤-0.75, 1≤Fb / F≤1.68, 0.6≤F18 / F≤0.65, 1.8≤ND1≤2.2, 60≤VD2≤100, 60≤VD4≤100, in, Dmax is the maximum full aperture of the viewing and aiming lens, TTL is the distance from the object side surface of the first lens to the imaging surface of the viewing and aiming lens on the optical axis, BFL is the back focus of the viewing and aiming lens, F1 is the effective focal length of the first lens, F2 is the effective focal length of the second lens, F3 is the effective focal length of the third lens, F4 is the effective focal length of the fourth lens, F5 is the effective focal length of the fifth lens, F7 is the effective focal length of the seventh lens, F8 is the effective focal length of the eighth lens, F9 is the effective focal length of the ninth lens, Fb is the combined effective focal length of the seventh lens and the eighth lens, F18 is the combined effective focal length of the first lens to the eighth lens, ND1 is the refractive index of the first lens, VD2 is the Abbe number of the second lens, and VD4 is the Abbe number of the fourth lens.

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