Small volume portable micro-lens

Abstract

The application discloses a small-size portable micro-light lens, which comprises, from an object side to an 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 in sequence; the first lens and the second lens are both positive focal length meniscus spherical lenses, the concave surfaces of the first lens and the second lens are both towards the image side, the first lens and the second lens are glued into one body; the third lens is a double-concave spherical lens with negative focal length; the fourth lens and the fifth lens are both double-convex spherical lenses with positive focal length; the sixth lens is a meniscus spherical lens with positive focal length, the concave surface of the sixth lens is towards the image side; the seventh lens is a double-concave spherical lens with negative focal length; the eighth lens is a double-convex spherical lens with positive focal length; and the ninth lens is a meniscus spherical lens with negative focal length, the concave surface of the ninth lens is towards the object side. Through reasonable structure matching of the multiple lenses, the lens is short and small, and is convenient to carry.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical elements, in particular to a small volume portable low-light lens. BACKGROUND

[0002] The low-light night vision lens is widely used in security monitoring, military equipment, national security, submarine exploration, satellite remote sensing, biological research and other fields. Because the low-light lens covers the near-infrared waveband, it is designed to cooperate with a large aperture, so that it has strong observation ability at night. This is also the incomparable advantage of ordinary visible light lenses. The large aperture, large target surface, small volume and light weight of the low-light lens are the current market trend, but it is also a design difficulty. In order to cooperate with the large target surface and large aperture, it is usually difficult to avoid large size and bulkiness. In view of the shortcomings of the prior art, the present application provides a low-light lens with a large aperture and a large target surface. Through reasonable structure matching, the lens is short and light, easy to carry, and is especially suitable for occasions with limited weight and volume. SUMMARY

[0003] The main purpose of the present application is to provide a small volume portable low-light lens, which aims to solve the problem that in the prior art, in order to cooperate with a large target surface and a large aperture, it is usually difficult to avoid large size and bulkiness.

[0004] To achieve the above purpose, the small volume portable low-light lens provided by the present application comprises:

[0005] The shell and the plurality of lenses arranged in the inner cavity of the shell in sequence, a plurality of lenses correspond to form an optical axis in the shell, wherein the plurality of lenses are sequentially arranged from the object side to the image side, comprising:

[0006] The first lens is arranged as a meniscus spherical lens with positive focal power, and the concave surface of the first lens is arranged towards the image side;

[0007] The second lens is arranged as a meniscus spherical lens with positive focal power, and the concave surface of the second lens is arranged towards the image side;

[0008] The third lens is arranged as a double-concave spherical lens with negative focal power;

[0009] The fourth lens is arranged as a double-convex spherical lens with positive focal power;

[0010] The fifth lens is arranged as a double-convex spherical lens with positive focal power;

[0011] The sixth lens is arranged as a meniscus spherical lens with positive focal power, and the concave surface of the sixth lens is arranged towards the image side;

[0012] The seventh lens is arranged as a double-concave spherical lens with negative focal power;

[0013] an eighth lens configured as a biconvex spherical lens with positive refractive power; and

[0014] a ninth lens configured as a meniscus spherical lens with negative refractive power, a concave surface of the ninth lens being configured to face the object side;

[0015] The first lens and the second lens are integrally configured by being cemented together.

[0016] Optionally, the material of the plurality of lenses is glass; and / or,

[0017] The aperture of the plurality of lenses is R, where R≤15mm.

[0018] Optionally, an aperture stop is arranged between the fifth lens and the sixth lens.

[0019] Optionally, the refractive index of the first lens is Nd1, where Nd1>2; and / or,

[0020] The refractive index of the fourth lens is Nd4, where Nd4>2.

[0021] Optionally, the total length of the micro-lens is L, and the total focal length of the micro-lens is f, where L / f<1.6.

[0022] Optionally, the dispersion coefficient of the first lens is Vd1, where 15<Vd1<30; and / or,

[0023] The dispersion coefficient of the second lens is Vd2, where 40<Vd2<60; and / or,

[0024] The dispersion coefficient of the third lens is Vd3, where 15<Vd3<30; and / or,

[0025] The dispersion coefficient of the fourth lens is Vd4, where 20<Vd4<40; and / or,

[0026] The dispersion coefficient of the fifth lens is Vd5, where 35<Vd5<55; and / or,

[0027] The dispersion coefficient of the sixth lens is Vd6, where 35<Vd6<55; and / or,

[0028] The dispersion coefficient of the seventh lens is Vd7, where 50<Vd7<70; and / or,

[0029] The dispersion coefficient of the eighth lens is Vd8, where 35<Vd8<50; and / or,

[0030] A dispersion coefficient of the ninth lens is Vd9, wherein 15 < Vd9 < 30.

[0031] Optionally, a field angle of the micro light lens is W, wherein W ≥ 49.5°.

[0032] Optionally, an optical total length of the micro light lens is ≤ 28.7mm.

[0033] Optionally, an optical back focal length is Fb, wherein Fb ≥ 2.15mm.

[0034] In the technical scheme, the first lens is arranged as a meniscus spherical lens with positive focal power, the concave surface of the first lens is arranged towards the image side, the second lens is arranged as a meniscus spherical lens with positive focal power, the concave surface of the second lens is arranged towards the image side, the first lens and the second lens are integrally arranged by being cemented together, and chromatic aberration, astigmatism and distortion are effectively corrected. The third lens is arranged as a double-concave spherical lens with negative focal power, so as to effectively offset the field curvature and distortion caused by the first lens and the second lens which are integrally cemented together, correct the incident light angle, and make the light smoothly enter the whole optical system, thereby reducing the assembly tolerance sensitivity of the lens. The fourth lens is arranged as a double-convex spherical lens with positive focal power, the fifth lens is arranged as a double-convex spherical lens with positive focal power, the sixth lens is arranged as a meniscus spherical lens with positive focal power, the concave surface of the sixth lens is arranged towards the image side, the fifth lens and the sixth lens are both arranged as positive focal power, so as to offset the spherical aberration and coma caused by other negative focal power lenses, shorten the lens length, the seventh lens is arranged as a double-concave spherical lens with negative focal power, the eighth lens is arranged as a double-convex spherical lens with positive focal power, the seventh lens and the eighth lens are arranged as a negative lens and a positive lens to offset aberration and reduce the tolerance sensitivity. The ninth lens is arranged as a meniscus spherical lens with negative focal power, the concave surface of the ninth lens is arranged towards the object side, the ninth lens adopts negative focal power to offset the remaining spherical aberration, field curvature and distortion, control the exit angle of the chief ray to adapt to the angle of the photosensitive chip, thereby improving the light energy response efficiency, making the lens present a high-quality imaging effect with uniform color and no dark angle, and realizing that the lens is short and light, is convenient to carry, and is especially suitable for occasions with limited weight and volume by reasonably distributing the focal power and reasonably arranging the structures of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only show some of the embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art based on these drawings without creative effort are within the scope of the present application.

[0036] Figure 1 The structural schematic diagram of an embodiment of the small-size portable micro light lens provided by the present application is shown in the figure.

[0037] Figure 2 The MTF curve diagram of the small-size portable micro light lens at room temperature is shown in the figure. Figure 1

[0038] Figure 3 The MTF curve diagram of the small-size portable micro light lens at low temperature-40℃ is shown in the figure. Figure 1

[0039] Figure 4 The MTF curve diagram of the small-size portable micro light lens at high temperature+80℃ is shown in the figure. Figure 1

[0040] The description of the reference signs is shown in the figure.

[0041]

[0042] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of the present application.

[0044] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between the components in a certain specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0045] ​​​In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes, for example, "A and / or B" includes A scheme, or B scheme, or A and B simultaneously satisfy the scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor in the protection scope required by the present application.

[0046] Micro light night vision lens is applied more and more widely in security monitoring, military equipment, national security, submarine exploration, satellite remote sensing, biological research and so on. Because the wavelength of micro light lens covers the near infrared band, the design is matched with large aperture, so that it has strong observation ability at night. This is also the incomparable advantage of ordinary visible light lens. The large aperture, large target surface, small volume and light weight of micro light lens are the current market trend, but this is also the design difficulty, in order to match the large target surface and large aperture, it is usually difficult to avoid large and bulky size. In view of the shortcomings of the prior art, the present application provides a micro light lens with large aperture and large target surface, which is short and light through reasonable structure matching, and is convenient to carry, especially suitable for various occasions with weight and volume restrictions.

[0047] The present application provides a small volume portable micro light lens, wherein, Figure 1 The structure diagram of the embodiment of the small volume portable micro light lens provided by the present application.

[0048] Please refer to Figure 1The small-volume portable micro-lens 100 comprises a shell and a plurality of lenses arranged in the shell cavity in sequence, and a plurality of lenses correspond to form an optical axis in the shell. The plurality of lenses comprise, in sequence from the object side to the image side, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, and a ninth lens 9. The first lens 1 is arranged as a meniscus spherical lens with positive focal power, the concave surface of the first lens 1 is arranged towards the image side, the second lens 2 is arranged as a meniscus spherical lens with positive focal power, the concave surface of the second lens 2 is arranged towards the image side, the third lens 3 is arranged as a double-concave spherical lens with negative focal power, the fourth lens 4 is arranged as a double-convex spherical lens with positive focal power, the fifth lens 5 is arranged as a double-convex spherical lens with positive focal power, the sixth lens 6 is arranged as a meniscus spherical lens with positive focal power, the concave surface of the sixth lens 6 is arranged towards the image side, the seventh lens 7 is arranged as a double-concave spherical lens with negative focal power, the eighth lens 8 is arranged as a double-convex spherical lens with positive focal power, the ninth lens 9 is arranged as a meniscus spherical lens with negative focal power, the concave surface of the ninth lens 9 is arranged towards the object side, and the first lens 1 and the second lens 2 are integrally arranged by cementing.

[0049] The first lens 1 is arranged as a meniscus spherical lens with positive focal length, the concave surface of the first lens 1 is arranged towards the image side, the second lens 2 is arranged as a meniscus spherical lens with positive focal length, the concave surface of the second lens 2 is arranged towards the image side, and the first lens 1 and the second lens 2 are integrally arranged by being cemented together, so that chromatic aberration, astigmatism and distortion are effectively corrected. The third lens 3 is arranged as a double-concave spherical lens with negative focal length, so as to effectively offset the field curvature and distortion caused by the first lens 1 and the second lens 2 which are integrally cemented together, correct the angle of the incident light, and make the light smoothly enter the whole optical system, thereby reducing the sensitivity of the lens adjustment tolerance. The fourth lens 4 is arranged as a double-convex spherical lens with positive focal length, the fifth lens 5 is arranged as a double-convex spherical lens with positive focal length, the sixth lens 6 is arranged as a meniscus spherical lens with positive focal length, the concave surface of the sixth lens 6 is arranged towards the image side, the fifth lens 5 and the sixth lens 6 are both arranged as positive focal length, so as to offset the spherical aberration and coma caused by other negative focal length lenses, and shorten the lens length. The seventh lens 7 is arranged as a double-concave spherical lens with negative focal length, the eighth lens 8 is arranged as a double-convex spherical lens with positive focal length, the seventh lens 7 and the eighth lens 8 are arranged as a negative lens and a positive lens to offset aberration and reduce the tolerance sensitivity. The ninth lens 9 is arranged as a meniscus spherical lens with negative focal length, the concave surface of the ninth lens 9 is arranged towards the object side, the ninth lens 9 adopts negative focal length to offset the remaining spherical aberration, field curvature and distortion, control the exit angle of the main light to adapt to the angle of the photosensitive chip, thereby improving the light energy response efficiency, making the lens present a high-quality imaging effect with uniform picture color and no dark angle, and realizing that the lens is short and light by reasonable structure matching of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens 8 and the ninth lens 9, so as to be convenient to carry, and be especially suitable for occasions with limited weight and volume.

[0050] It should be noted that the basic parameter table of the small-size portable micro light lens 100 in the embodiment is shown in Table 1, wherein the units of the curvature radius and the thickness are millimeters (mm).

[0051] Table 1

[0052]

[0053] Specifically, the material of the plurality of lenses can be plastic or glass. In this embodiment, the material of the plurality of lenses is glass. In this way, the small-volume portable low-light lens 100 is suitable for occasions with high overall performance requirements, such as military products (for example, can be widely used in security monitoring, military equipment, national security, submarine exploration, satellite remote sensing, biological research, and other aspects). In addition, the thermal parameters of the glass material can well correct aberration and offset the thermal effects generated by the structure, so that the small-volume portable low-light lens 100 can still clearly image in an environment of -40°C to +80°C, meeting the application in different temperature environments.

[0054] Further, the aperture of the plurality of lenses is R, where R≤15mm. In this way, the volume of the low-light lens 100 is small, which is convenient to carry.

[0055] Specifically, referring to Figure 1 , the fifth lens 5 and the sixth lens 6 are provided with a diaphragm a. In this way, the apertures of the plurality of lenses are uniform in the direction of the optical axis, which reduces the volume of the low-light lens 100 to a certain extent. In addition, the diaphragm a can limit the on-axis beam aperture and help improve the image quality.

[0056] Specifically, the refractive index of the first lens 1 is Nd1, where Nd1>2. In this way, the first lens 1 has a high refractive index, which can effectively shorten the total length of the lens and miniaturize the system.

[0057] Specifically, the refractive index of the fourth lens 4 is Nd4, where Nd4>2. The fourth lens 4 has a high refractive index, which can effectively shorten the total length of the lens and miniaturize the system.

[0058] It should be noted that the features of the first lens 1 and the fourth lens 4 described above can be satisfied at the same time or alternatively. When both are satisfied at the same time, the total length of the lens is shortened to the greatest extent, the system is miniaturized, and the effect is the best.

[0059] Specifically, in order to make the small-volume portable low-light lens 100 applicable to more scenarios, in this embodiment, the total length of the low-light lens 100 is L, and the total focal length of the low-light lens 100 is f, where L / f<1.6. In this way, the lens miniaturization trend is met, which can meet the military requirements and also meet the daily portable needs.

[0060] Further, a dispersion coefficient of the first lens 1 is Vd1, wherein 15 < Vd1 < 30; and / or, a dispersion coefficient of the second lens 2 is Vd2, wherein 40 < Vd2 < 60; and / or, a dispersion coefficient of the third lens 3 is Vd3, wherein 15 < Vd3 < 30; and / or, a dispersion coefficient of the fourth lens 4 is Vd4, wherein 20 < Vd4 < 40; and / or, a dispersion coefficient of the fifth lens 5 is Vd5, wherein 35 < Vd5 < 55; and / or, a dispersion coefficient of the sixth lens 6 is Vd6, wherein 35 < Vd6 < 55; and / or, a dispersion coefficient of the seventh lens 7 is Vd7, wherein 50 < Vd7 < 70; and / or, a dispersion coefficient of the eighth lens 8 is Vd8, wherein 35 < Vd8 < 50; and / or, a dispersion coefficient of the ninth lens 9 is Vd9, wherein 15 < Vd9 < 30, so that the dispersion of the small-volume portable low-light lens 100 is not obvious, and the imaging quality of the lens is good.

[0061] It should be noted that in the embodiments of the present application, by appropriately distributing the optical power, the glass with a refractive index Nd > 1.7 is basically used, because the higher the refractive index of the glass, the faster the focusing, the shorter the lens length, and the smaller the volume, and at the same time, the seventh lens 7 is arranged as a glass with a low refractive index and a high dispersion (Vd7 > 60) to offset the chromatic aberration caused by the high refractive index glass (here, the chromatic aberration is caused by the glass material, and can also be corrected by the shape of the glass as mentioned above). In the case of selecting a high refractive index glass to reduce the length as much as possible, the thermal expansion coefficients of the selected glass materials are basically less than 7, compared with other glass materials with thermal expansion coefficients greater than 8, greater than 9 or even 10 or more. The smaller the thermal expansion coefficient, the smaller the thermal expansion deformation at high and low temperatures, which not only reduces the image difference caused by the change of the glass surface shape, but also reduces the thermal effect of the structural parts, thereby achieving the effect of clear imaging at 40℃ to +80℃.

[0062] Specifically, the field of view of the low-light lens 100 is W, wherein W ≥ 49.5°, so that the small-volume portable low-light lens 100 has a larger field of view.

[0063] Specifically, in the embodiments of the present application, the total optical length of the low-light lens 100 is ≤ 28.7mm, so that the small-volume portable low-light lens 100 has a small volume and is convenient to carry.

[0064] Specifically, in the embodiments of the present application, the optical back intercept is Fb, wherein Fb ≥ 2.15mm, so as to provide space for subsequent chip mounting.

[0065] It should be noted that the small volume portable micro light lens 100 has a large aperture, F / #≤1.25, and the aperture of the small volume portable micro light lens 100 is increased, which is more suitable for the environment with insufficient light, so that a brighter picture can be presented at night, the plurality of lenses are all spherical surfaces, and there is no aspherical surface, the cost is controlled, the yield of finished products is improved, the high reliability of the product is ensured, the military standard is reached, the total length of the lens of the small volume portable micro light lens 100 is controlled to be very short, the lens length / focal length is less than 1.6, the total weight of the plurality of lenses is less than 10g, the maximum aperture is 15mm, the volume is small, the imaging circle diameter of the small volume portable micro light lens 100 is φ, wherein φ>16mm, the F-Tan distortion of the small volume micro light lens 100 is less than or equal to 3.2%, in addition, the small volume micro light lens 100 can work in the working waveband of the spectral range of 600nm~1000nm,

[0066] In addition, Figures 2 to 4 The MTF curves of the small volume micro light lens 100 at normal temperature, low temperature-40℃ and high temperature+80℃ are shown in the drawings, it can be seen from the drawings that the MTF is greater than or equal to 0.3 in the 0.8 field of view at 50lp at normal temperature, the imaging quality is high, and the performance difference of various temperature states is small, the consistency is good, and clear imaging at high and low temperatures can be achieved without focusing.

[0067] The above only describes the preferred embodiments of the present application, and does not limit the patent range of the present application, and any equivalent structural transformation made under the concept of the present application, using the content of the present application specification and drawings, or directly / indirectly applied in other related technical fields are included in the patent protection range of the present application.

Claims

1. A small volume portable micro-lens, characterized by, The micro-light lens comprises a shell and a plurality of lenses arranged in the inner cavity of the shell in sequence, and an optical axis is formed in the shell between the plurality of lenses. The first lens is arranged as a meniscus spherical lens with positive refractive power, and the concave surface of the first lens is arranged towards the image side. The second lens is arranged as a meniscus spherical lens with positive refractive power, and the concave surface of the second lens is arranged towards the image side. The third lens is arranged as a biconcave spherical lens with negative refractive power. The fourth lens is arranged as a biconvex spherical lens with positive refractive power. The fifth lens is arranged as a biconvex spherical lens with positive refractive power. The sixth lens is arranged as a meniscus spherical lens with positive refractive power, and the concave surface of the sixth lens is arranged towards the image side. The seventh lens is arranged as a biconcave spherical lens with negative refractive power. The eighth lens is arranged as a biconvex spherical lens with positive refractive power. The ninth lens is arranged as a meniscus spherical lens with negative refractive power, and the concave surface of the ninth lens is arranged towards the object side. The first lens and the second lens are integrally arranged by cementing.

2. The small volume portable micro-lens according to claim 1, wherein, The material of the plurality of lenses comprises glass; and / or The aperture of the plurality of lenses is R, wherein R≤15mm.

3. The small volume portable micro-lens according to claim 1, wherein, An aperture stop is arranged between the fifth lens and the sixth lens.

4. The small volume portable micro-lens according to claim 1, wherein, The refractive index of the first lens is Nd1, wherein Nd1≥2; and / or The refractive index of the fourth lens is Nd4, wherein Nd4≥2.

5. The small volume portable micro-lens according to claim 1, wherein, The total length of the micro-light lens is L, and the total focal length of the micro-light lens is f, wherein L / f<1.

6.

6. The small volume portable micro-lens according to claim 1, wherein, The dispersion coefficient of the first lens is Vd1, wherein 15<Vd1<30; and / or The dispersion coefficient of the second lens is Vd2, wherein 40<Vd2<60; and / or The dispersion coefficient of the third lens is Vd3, wherein 15<Vd3<30; and / or The dispersion coefficient of the fourth lens is Vd4, wherein 20<Vd4<40; and / or The dispersion coefficient of the fifth lens is Vd5, wherein 35<Vd5<55; and / or The dispersion coefficient of the sixth lens is Vd6, wherein 35<Vd6<55; and / or The dispersion coefficient of the seventh lens is Vd7, wherein 50<Vd7<70; and / or The dispersion coefficient of the eighth lens is Vd8, wherein 35<Vd8<50; and / or The dispersion coefficient of the ninth lens is Vd9, wherein 15<Vd9<30.

7. The small volume portable micro-lens according to claim 1, wherein, The field of view angle of the micro-light lens is W, wherein W≥49.5°.

8. The small volume portable micro-lens according to claim 1, wherein, The total optical length of the micro-light lens is ≤28.7mm.

9. The small volume portable micro-lens according to claim 1, wherein, The optical back intercept is Fb, wherein Fb≥2.15mm.

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