Black light level day and night dual-purpose large light transmission fixed focus lens and working method thereof

Abstract

The present invention relates to a 6mm black light level day and night dual-purpose large light transmission fixed focus lens and a working method thereof, wherein the optical system of the lens comprises a front lens group A with negative optical focal length and a rear lens group B with positive optical focal length, which are arranged in sequence from front to back along an incident light path, wherein the front lens group A comprises a negative meniscus lens A‑1, a negative meniscus lens A‑2 and a biconvex lens A‑3, which are arranged in sequence from front to back; and the rear lens group B comprises a glued lens group of a biconcave lens B‑1 and a biconvex lens B‑2, which are closely connected, a biconvex lens B‑3, a biconcave lens B‑4 and a biconvex lens B‑5, which are arranged in sequence from front to back. The vertex lens of the present invention has a simple structure, a reasonable design, a low manufacturing cost, a short total optical path length, a small volume and good imaging quality; the F value is extremely small, and the light transmission of the lens is increased, which not only makes the overall picture brighter, but also makes the lens perform better in a low-light environment, presents a clearer imaging effect, and realizes a universal function for day and night.

Description

Technical field:

[0002] The invention relates to a 6mm black light level day and night dual-purpose large light transmission fixed focus lens, belonging to the technical field of optical devices. Background technology:

[0004] With the rapid development of the camera lens market, in recent years, relatively standardized, stable miniature camera lenses that can be used with cameras have been formed. Under stable lens imaging conditions, customers' requirements for lens light transmittance are constantly increasing. The security lenses on the current market have problems with low light transmittance and unclear imaging. Summary of the invention;

[0006] In view of this, the object of the present invention is to provide a 6mm black light level day and night dual-use large light transmission fixed focus lens with small size, large light transmission and good imaging quality.

[0007] The present invention is implemented by the following scheme: a 6mm black light level day and night dual-purpose wide-clearance fixed-focus lens, characterized in that: the optical system of the lens comprises a front lens group A with negative focal length and a rear lens group B with positive focal length, which are arranged in sequence from front to back along an incident light path, the front lens group A comprises a first negative meniscus lens, a second negative meniscus lens and a first biconvex lens, which are arranged in sequence from front to back; the rear lens group B comprises a first biconcave lens and a second biconvex lens, which are arranged in sequence from front to back and are in close contact with each other, a third biconvex lens, a second biconcave lens and a fourth biconvex lens.

[0008] Furthermore, an aperture C is provided between the front lens group A and the rear lens group B, the air gap between the front lens group A and the rear lens group B is 1.5 mm, and the air gap between the first biconvex lens and the aperture C is 0.012 mm.

[0009] Furthermore, the air gap between the first negative meniscus lens and the second negative meniscus lens is 3.0 mm, the air gap between the second negative meniscus lens and the first biconvex lens is 0.08 mm, the air gap between the second biconvex lens and the third biconvex lens is 0.09 mm, the air gap between the third biconvex lens and the second biconcave lens is 1.0 mm, and the air gap between the second biconcave lens and the fourth biconvex lens is 0.05 mm.

[0010] Furthermore, the first negative meniscus lens is a glass spherical lens, the second negative meniscus lens is a plastic aspherical lens, the first biconvex lens is a glass spherical lens, the first biconcave lens is a glass spherical lens, the second biconvex lens is a glass spherical lens, the third biconvex lens is a plastic aspherical lens, the second biconcave lens is a plastic aspherical lens, and the fourth biconvex lens is a plastic aspherical lens.

[0011] Furthermore, the mechanical structure of the above-mentioned lens includes a main lens barrel, which is a cylindrical structure with four-step holes inside. A first spacer is arranged between the second negative meniscus lens and the first double convex lens, a second spacer is arranged between the first double convex lens and the first double concave lens, and a third spacer is arranged between the second double convex lens and the third double convex lens. The rear end inner hole of the main lens barrel is provided with an annular flange for supporting the outer edge of the rear end surface of the fourth double convex lens, and the front end of the main lens barrel is provided with a step for fixing the first negative meniscus lens by gluing.

[0012] The invention discloses a working method of a 6mm black light level day and night dual-purpose wide-through fixed-focus lens. The 6mm black light level day and night dual-purpose wide-through fixed-focus lens comprises an optical system comprising a front lens group A with negative focal power and a rear lens group B with positive focal power, which are sequentially arranged from front to back along an incident light path. The front lens group A comprises a first negative meniscus lens, a second negative meniscus lens and a first biconvex lens, which are sequentially arranged from front to back; and the rear lens group B comprises a first biconcave lens and a second biconvex lens, a third biconvex lens, a second biconcave lens and a fourth biconvex lens, which are sequentially arranged from front to back. When working, light enters from the front end of the front lens group A, passes through the first negative meniscus lens, the second negative meniscus lens and the first biconvex lens of the front lens group A, and a stop C in sequence, and then enters the first biconcave lens, the second biconvex lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens of the rear lens group B, and finally reaches a filter and an optical target surface.

[0013] The focal length f, refractive index n and curvature radius R of the above eight lenses satisfy the following relationship:

[0014] -15.14≤f1≤-10.25, -21.5≤f2≤-8.5, 5.14≤f3≤15.25, -25.1≤f4≤-100.1, 9.14≤f5≤20.5, 5.1≤f6≤9.15, -8.1≤f7≤-4.15, 4.1≤f8≤8.15;

[0015] 1.43≤n1≤1.72, 1.4≤n2≤1.65, 1.7≤n3≤2.0, 1.5≤n4≤1.75, 1.4≤n5≤1.65, 1.4≤n6≤1.65, 1.6≤n7≤1.75, 1.4≤n8≤1.65;

[0016] 180≤R1≤220, -5≤R3≤-2.3, 10.2≤R5≤28.25, -13.14≤R7≤-8.25, -13.14≤R9≤-9.2, 5.14≤R11≤8.25, -1.14≤R13≤-5.25, 2.14≤R15≤8.25;

[0017] 4.1≤R2≤8.25, -8.14≤R4≤-3.25, -28.5≤R6≤-10.2, 5.14≤R8≤10.25, -10.14≤R10≤-4.5, -12.14≤R12≤-8.3, -10.14≤R14≤-4.2, -14.14≤R16≤-8.25.

[0018] Wherein, f1 to f8 correspond to the focal lengths of the first negative meniscus lens A-1, the second negative meniscus lens, the first biconvex lens, the first biconcave lens, the second biconvex lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens, respectively; n1 to n8 correspond to the refractive indices of the first negative meniscus lens, the second negative meniscus lens, the first biconvex lens, the first biconcave lens, the second biconvex lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens, respectively; R1, R3, R5, R7, R9, R11, R13 and R15 corresponds to the curvature radii of the front mirror surfaces of the first negative meniscus lens, the second negative meniscus lens, the first biconvex lens, the first biconcave lens, the second biconvex lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens, respectively; R2, R4, R6, R8, R10, R12, R14 and R16 correspond to the curvature radii of the rear mirror surfaces of the first negative meniscus lens, the second negative meniscus lens, the first biconvex lens, the first biconcave lens, the second biconvex lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens, respectively.

[0019] Furthermore, the specific parameters of the above lenses are shown in the following table:

[0020] Surface number Face type R D nd K Value 1 Spherical 217 0.6 1.44 2 Spherical 6 3 3 Aspheric -2.6 0.7 1.64 -1.1 4 Aspheric -4 0.08 -1.1 5 Spherical 16.24 2.1 2.00 6 Spherical -16.24 0.012 stop flat 0 1.5 7 Spherical -9.5 0.6 1.65 8 Spherical 9.5 0.005 9 Spherical 9.5 2.7 1.59 10 Spherical -9.5 0.09 11 Aspheric 5.6 3.1 1.53 -0.5 12 Aspheric -10.2 1 -46 13 Aspheric -1.9 0.7 1.64 -4.7 14 Aspheric -4.5 0.05 -12 15 Aspheric 5.9 1.3 1.53 --39 16 Aspheric -11 4.7 10

[0021] The aspheric surface equations of the second negative meniscus lens, the third biconvex lens, the second biconcave lens and the fourth biconvex lens are as follows:

[0022] ,

[0023] Surface number: 3 Surface number: 4 Surface number: 11 Surface number: 12 Surface number: 13 Surface number: 14 Surface number: 15 Surface number: 16 α1 parameter 6.9E-003 6.0E-003 3.5E-004 -2.3E-003 5.8E-003 4.8E-003 -0.017 -3.3E-003 α2 parameter -7.5E-005 7.2E-005 -8.2E-005 3.5E-004 -6.3E-005 1.2E-003 4.8E-003 5.8E-004 α3 parameter -4.7E-005 -4.6E-005 1.2E-005 -2.5E-005 -2E-005 -1.6E-004 -6.1E-004 1.6E-004 α4 parameter 5.6E-006 4.4E-006 -1.6E-006 1.0E-006 -9.3E-007 -2.2E-006 4.4E-005 -3.5E-005 α5 parameter -2.9E-007 -2E-007 1.1E-007 -8E-008 2.8E-007 1.5E-006 -1.3E-006 3.4E-006 α6 parameter 0 0 0 0 0 0 0 0 α7 parameters 0 0 0 0 0 0 0 0 α8 parameters 0 0 0 0 0 0 0 0

[0024] Compared with the prior art, the present invention has the following beneficial effects: the top angle lens of the present invention has a simple structure, reasonable design, low manufacturing cost, short total optical path length, small size and good imaging quality; the F value is extremely small, which increases the light transmittance of the lens, not only making the overall picture brighter, but also making the lens perform better in low-light environments, presenting a clearer imaging effect, and realizing universal functions during day and night.

[0025] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through specific embodiments and related drawings. Description of the drawings:

[0027] Figure 1 is a light path diagram of a lens light system according to an embodiment of the present invention; Specific implementation method:

[0029] like Figure 1 As shown, a 6mm black light level day and night dual-purpose wide-clearance fixed-focus lens, the optical system of the lens includes a front lens group A with negative optical focal length and a rear lens group B with positive optical focal length, which are arranged in sequence from front to back along the incident light path, the front lens group A includes a first negative meniscus lens A-1, a second negative meniscus lens A-2 and a first biconvex lens A-3, which are arranged in sequence from front to back; the rear lens group B includes a first biconcave lens B-1 and a second biconvex lens B-2, which are closely bonded, a third biconvex lens B-3, a second biconcave lens B-4 and a fourth biconvex lens B-5, which are arranged in sequence from front to back.

[0030] The first negative meniscus lens A-1 is a glass spherical lens, the second negative meniscus lens A-2 is a plastic aspherical lens, the first biconvex lens A-3 is a glass spherical lens, the first biconcave lens B-1 is a glass spherical lens, the second biconvex lens B-2 is a glass spherical lens, the third biconvex lens B-3 is a plastic aspherical lens, the second biconcave lens B-4 is a plastic aspherical lens, and the fourth biconvex lens B-5 is a plastic aspherical lens.

[0031] In this embodiment, an aperture C is arranged between the front lens group A and the rear lens group B, a filter is arranged behind the rear lens group B, the air gap between the fourth biconvex lens B-5 and the filter is 2.29 mm, the air gap between the front lens group A and the rear lens group B is 1.5 mm, and the air gap between the first biconvex lens A-3 and the aperture C is 0.012 mm.

[0032] In this embodiment, the air gap between the first negative meniscus lens A-1 and the second negative meniscus lens A-2 is 3.0 mm, the air gap between the second negative meniscus lens A-2 and the first biconvex lens A-3 is 0.08 mm, the air gap between the second biconvex lens B-2 and the third biconvex lens B-3 is 0.09 mm, the air gap between the double third convex lens B-3 and the second biconcave lens B-4 is 1.0 mm, and the air gap between the second biconcave lens B-4 and the fourth biconvex lens B-5 is 0.05 mm.

[0033] The first negative meniscus lens A-1, the second negative meniscus lens A-2, the first biconvex lens A-3, the first biconcave lens B-1, the second biconvex lens B-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5, the focal length f, the refractive index n and the curvature radius R of the above eight lenses satisfy the following relationship:

[0034] -15.14≤f1≤-10.25, -21.5≤f2≤-8.5, 5.14≤f3≤15.25, -25.1≤f4≤-100.1, 9.14≤f5≤20.5, 5.1≤f6≤9.15, -8.1≤f7≤-4.15, 4.1≤f8≤8.15;

[0035] 1.43≤n1≤1.72, 1.4≤n2≤1.65, 1.7≤n3≤2.0, 1.5≤n4≤1.75, 1.4≤n5≤1.65, 1.4≤n6≤1.65, 1.6≤n7≤1.75, 1.4≤n8≤1.65;

[0036] 180≤R1≤220, -5≤R3≤-2.3, 10.2≤R5≤28.25, -13.14≤R7≤-8.25, -13.14≤R9≤-9.2, 5.14≤R11≤8.25, -1.14≤R13≤-5.25, 2.14≤R15≤8.25;

[0037] 4.1≤R2≤8.25, -8.14≤R4≤-3.25, -28.5≤R6≤-10.2, 5.14≤R8≤10.25, -10.14≤R10≤-4.5, -12.14≤R12≤-8.3, -10.14≤R14≤-4.2, -14.14≤R16≤-8.25.

[0038] Wherein, f1 to f8 correspond to the focal lengths of the first negative meniscus lens A-1, the second negative meniscus lens A-2, the first biconvex lens A-3, the first biconcave lens B-1, the second biconvex lens B-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5, respectively; n1 to n8 correspond to the refractive indices of the first negative meniscus lens A-1, the second negative meniscus lens A-2, the first biconvex lens A-3, the first biconcave lens B-1, the second biconvex lens B-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5, respectively; R1, R3, R5, R7, R9, R11, R13 and R 15 respectively correspond to the curvature radii of the front mirror surfaces of the first negative meniscus lens A-1, the second negative meniscus lens A-2, the first biconvex lens A-3, the first biconcave lens B-1, the second biconvex lens B-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5, and R2, R4, R6, R8, R10, R12, R14 and R16 respectively correspond to the curvature radii of the back mirror surfaces of the first negative meniscus lens A-1, the second negative meniscus lens A-2, the first biconvex lens A-3, the first biconcave lens B-1, the second biconvex lens B-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5.

[0039] Surface number Face type R D nd K Value 1 Spherical 217 0.6 1.44 2 Spherical 6 3 3 Aspheric -2.6 0.7 1.64 -1.1 4 Aspheric -4 0.08 -1.1 5 Spherical 16.24 2.1 2.00 6 Spherical -16.24 0.012 stop flat 0 1.5 7 Spherical -9.5 0.6 1.65 8 Spherical 9.5 0.005 9 Spherical 9.5 2.7 1.59 10 Spherical -9.5 0.09 11 Aspheric 5.6 3.1 1.53 -0.5 12 Aspheric -10.2 1 -46 13 Aspheric -1.9 0.7 1.64 -4.7 14 Aspheric -4.5 0.05 -12 15 Aspheric 5.9 1.3 1.53 --39 16 Aspheric -11 4.7 10

[0040] The aspheric surface equations of the second negative meniscus lens A-2, the third biconvex lens B-3, the second biconcave lens B-4 and the fourth biconvex lens B-5 are as follows:

[0041] ,

[0042] Surface number: 3 Surface number: 4 Surface number: 11 Surface number: 12 Surface number: 13 Surface number: 14 Surface number: 15 Surface number: 16 α1 parameter 6.9E-003 6.0E-003 3.5E-004 -2.3E-003 5.8E-003 4.8E-003 -0.017 -3.3E-003 α2 parameter -7.5E-005 7.2E-005 -8.2E-005 3.5E-004 -6.3E-005 1.2E-003 4.8E-003 5.8E-004 α3 parameter -4.7E-005 -4.6E-005 1.2E-005 -2.5E-005 -2E-005 -1.6E-004 -6.1E-004 1.6E-004 α4 parameter 5.6E-006 4.4E-006 -1.6E-006 1.0E-006 -9.3E-007 -2.2E-006 4.4E-005 -3.5E-005 α5 parameter -2.9E-007 -2E-007 1.1E-007 -8E-008 2.8E-007 1.5E-006 -1.3E-006 3.4E-006 α6 parameter 0 0 0 0 0 0 0 0 α7 parameters 0 0 0 0 0 0 0 0 α8 parameters 0 0 0 0 0 0 0 0

[0043] The present invention is a fixed-focus lens with a focal length of 6mm. By reasonably using a combination of glass lenses and plastic lenses and adopting a 4G4P glass-plastic combined optical structure, the advantages of easy processing of glass lenses and low cost of plastic lenses are fully utilized. At the same time, the aperture is large, the F value is 1.0, the field of view angle is 70 degrees, the total optical length of the lens is less than 22.5mm, the size is compact, and it can be adapted to a variety of interfaces; the imaging quality is good, and a clear and bright monitoring picture can be achieved even under low illumination at night, realizing universal functions during day and night, and at the same time, it can be used in an environment of -30 to +80°C without shifting the focus.

[0044] In this embodiment, the mechanical structure of the lens includes a main lens barrel, which is a cylindrical structure with four-step holes inside. The inner diameter of the main lens barrel decreases step by step along the incident direction of light. A first spacer is arranged between the second negative meniscus lens A-2 and the first biconvex lens A-3, a second spacer is arranged between the first biconvex lens A-3 and the first biconcave lens B-1, and a third spacer is arranged between the second biconvex lens B-2 and the third biconvex lens B-3. The first spacer is provided with a first sharp-angled constriction for blocking invalid light, the second spacer is provided with a second sharp-angled constriction for blocking invalid light, and the third spacer is provided with a third sharp-angled constriction for blocking invalid light.

[0045] The first negative meniscus lens A-1 and the second negative meniscus lens A-2 are tightly matched through soma (light shielding film), the second negative meniscus lens A-2 and the first biconvex lens A-3 are tightly matched through the first spacer, the first biconvex lens A-3 and the first biconcave lens B-1 are tightly matched through the second spacer, the second biconvex lens B-2 and the third biconvex lens B-3 are tightly matched through the third spacer, the third biconvex lens B-3 and the second biconcave lens B-4 are tightly matched through soma (light shielding film), and the second biconcave lens B-4 and the fourth biconvex lens B-5 are tightly matched through soma (light shielding film).

[0046] The rear end inner hole of the main lens barrel is provided with an annular flange for supporting the outer edge of the rear end surface of the fourth biconvex lens B-5, and the rear end outer side of the annular flange is provided with a glue dispensing groove for installing the filter. The rear end of the main lens barrel is provided with a threaded portion for cooperating with the camera base, and the front end of the main lens barrel is provided with a step for fixing the first negative meniscus lens A-1 by glue.

[0047] Unless otherwise stated, any technical solution disclosed in the present invention disclosed above, if it discloses a numerical range, then the disclosed numerical range is a preferred numerical range, and any technician in the field should understand that the preferred numerical range is only a numerical value with a more obvious technical effect or representative value among many implementable numerical values. Since there are too many numerical values ​​to be exhaustive, the present invention discloses some numerical values ​​to illustrate the technical solution of the present invention, and the numerical values ​​listed above should not constitute a limitation on the scope of protection of the present invention.

[0048] If the present invention discloses or involves components or structures that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by integrated molding using a casting process) (except when it is obviously impossible to use an integrated molding process).

[0049] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in the present invention include states or shapes that are approximate, similar, or close to them.

[0050] Any component provided by the present invention may be assembled from a plurality of separate components, or may be a separate component manufactured by an integral forming process.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A 6mm blacklight-grade day and night dual-use wide-light fixed-focus lens, characterized by: The optical system of the lens comprises a front lens group A with negative focal power and a rear lens group B with positive focal power, which are arranged in sequence from front to back along an incident light path. The front lens group A comprises a first negative meniscus lens (A-1), a second negative meniscus lens (A-2) and a first biconvex lens (A-3) which are arranged in sequence from front to back; the rear lens group B comprises a first biconcave lens (B-1) and a second biconvex lens (B-2) which are closely connected, a third biconvex lens (B-3), a second biconcave lens (B-4) and a fourth biconvex lens (B-5) which are arranged in sequence from front to back; an aperture C is arranged between the front lens group A and the rear lens group B, and the air gap between the first biconvex lens (A-3) and the aperture C is 0.012 m. m; the air gap between the first negative meniscus lens (A-1) and the second negative meniscus lens (A-2) is 3.0 mm, the air gap between the second negative meniscus lens (A-2) and the first biconvex lens (A-3) is 0.08 mm, the air gap between the second biconvex lens (B-2) and the third biconvex lens (B-3) is 0.09 mm, the air gap between the third biconvex lens (B-3) and the second biconcave lens (B-4) is 1.0 mm, and the air gap between the second biconcave lens (B-4) and the fourth biconvex lens (B-5) is 0.05 mm; the first negative meniscus lens (A-1) is a glass spherical lens, the second negative meniscus lens (A-2) is a plastic aspherical lens, The first biconvex lens (A-3) is a glass spherical lens, the first biconcave lens (B-1) is a glass spherical lens, the second biconvex lens (B-2) is a glass spherical lens, the third biconvex lens (B-3) is a plastic aspherical lens, the second biconcave lens (B-4) is a plastic aspherical lens, and the fourth biconvex lens (B-5) is a plastic aspherical lens; the mechanical structure of the lens comprises a main lens barrel, the main lens is a cylindrical structure with four-level stepped holes inside, a first spacer is provided between the second negative meniscus lens (A-2) and the first biconvex lens (A-3), a second spacer is provided between the first biconvex lens (A-3) and the first biconcave lens (B-1), the second biconvex lens (B-2) and the third biconvex lens A third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the front lens group A and the rear lens group B, a third spacer is arranged between the rear lens group A and the rear lens group B, a third spacer is arranged between the rear lens group B ... The specific parameters of each lens are shown in the table below: The specific parameters of each lens are shown in the table below: ， The aspheric surface equations of the second negative meniscus lens (A-2), the third biconvex lens (B-3), the second biconcave lens (B-4) and the fourth biconvex lens (B-5) are as follows: ， Where c is the basic curvature of the surface center, k represents the cone coefficient, r is the radial coordinate of the point on the surface, A0~A4 are high-order aspheric coefficients, and the parameter values ​​are shown in the following table: 。

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