Wide-angle, full-length fixed zoom camera lens for robots

Abstract

A wide-angle full-length fixed zoom photography lens for robots, comprising: a first positive focal power lens group, a second negative focal power lens group, a third positive focal power lens group, a fourth negative focal power lens group, a filter for passing visible light and infrared light, and an imaging surface arranged in sequence from the object side to the image side; an aperture is provided in the third positive focal power lens group. The present invention adopts a four-group three-group linkage zoom structure, which is used to realize a wide-angle zoom photography system at a fixed length; a negative group is used as a focusing group to reduce the total length of the system; three aspherical surfaces are used to cooperate with the movement of the group to achieve a 20 million resolution, and the resolution is uniform from the center to the edge of the picture.

Description

Technical Field

[0001] The invention relates to a technology in the field of photographic lenses, in particular to a wide-angle, full-length, fixed-zoom photographic lens for robots. Background Art

[0002] The existing wide-angle photography zoom lens for robots can be fully variable in length to achieve a larger field of view at a smaller aperture; however, the target surface of the photography lens is generally very large, and to achieve higher resolution and larger aperture, the length needs to be increased. For robots, the variable full-length lens is not conducive to installation and will also increase the difficulty of installation. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention proposes a wide-angle, full-length fixed zoom photography lens for robots, which adopts a four-group and three-group linked zoom structure to realize a wide-angle zoom photography system at a fixed length; a negative group is used as a focusing group to reduce the total length of the system; three aspherical surfaces are used to cooperate with the movement of the group to achieve a resolution of 20 million, and the resolution is uniform from the center to the edge of the picture.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention comprises: a first positive power lens group, a second negative power lens group, a third positive power lens group, a fourth negative power lens group, a filter for passing visible light and infrared light, and an imaging surface arranged in sequence from the object surface side to the image surface side.

[0006] A stop is arranged inside the third positive power lens group.

[0007] The first positive power lens group comprises: a plurality of first positive power spherical lenses arranged in sequence from the object side along the optical axis.

[0008] The second negative power lens group comprises: a plurality of second negative power spherical lenses, a third negative power spherical lens and a fourth positive power aspherical lens, which are arranged in sequence from the object side along the optical axis.

[0009] The third positive power lens group includes: a plurality of fifth positive power aspheric lenses, a sixth positive power spherical lens and a seventh negative power spherical lens which can be glued together into a doublet lens, and an eighth positive power aspheric lens and a ninth positive power spherical lens which are arranged in sequence from the object side along the optical axis, wherein: the fifth positive power aspheric lens and the sixth positive power spherical lens are arranged on both sides of the aperture.

[0010] The fourth negative optical power lens group comprises: a plurality of tenth negative optical power spherical lenses arranged in sequence from the object side along the optical axis.

[0011] The ratio of the focal length of the first positive power lens group to the focal length at the wide angle end is f A / f W is (8,12); the ratio of the focal length of the second negative focal power lens group to the focal length of the wide angle end is f B / f W is (-2.5, -0.5); the ratio of the focal length of the third positive focal power lens group to the focal length of the wide angle end is f C / f W is (1.5,3.5); the ratio of the focal length of the fourth negative power lens group to the focal length at the wide angle end is f D / f W is (-3.5,-1.5).

[0012] The ratio f of the focal length of the first positive power spherical lens to the focal length of the first positive power lens group is A1 / f A is: (0.5,1.0).

[0013] The ratio f of the focal length 11 of the second negative power spherical lens, the third negative power spherical lens and the fourth positive power aspherical lens to the focal length of the second negative power lens group is B1 / f B 、f B2 / f B 、f B3 / f B They are: (0.9, 1.77), (0.9, 1.77), (-2.77, -1.75) respectively.

[0014] The ratio f of the focal length of the fifth positive power aspheric lens, the sixth positive power spherical lens, the seventh negative power spherical lens, the eighth positive power aspheric lens, the ninth positive power spherical lens to the focal length of the third positive power lens group is C1 / f C 、f C2 / f C 、f C3 / f C 、f C4 / f C 、f C5 / f C They are: (0.88, 1.1), (0.55, 0.7), (-0.42, -0.21), (1.19, 1.55), (0.58, 0.97), the ratio of the focal length of the double cemented lens to the focal length of the third positive power lens group f C2C3 / f C is: (-1.05,-0.64).

[0015] The iris is a variable iris, which can be adjusted accordingly as the ambient light intensity increases. The position of the iris is: L S-L1 / L C ∈(0.39,0.55), where: L S-L1 L is the distance from the aperture to the first optical surface of the third positive power lens group. C It is the total optical length of the third positive power lens group (i.e. the distance from the central vertex of the front surface of the first lens to the central vertex of the back surface of the last lens in the third positive power lens group).

[0016] The refractive index Nd of the first positive power spherical lens is A1 is: (1.3, 1.65), Abbe number Vd A1 is: (60,100).

[0017] The refractive index Nd of the fourth positive power aspheric lens is B3 is: (1.8, 2.0), Abbe number Vd B3 is: (15,40).

[0018] The refractive index Nd of the fifth positive power aspheric lens, the eighth positive power aspheric lens and the ninth positive power spherical lens is C3 、Nd C4 、Nd C4 The Abbe numbers Vd of the seventh negative power spherical lens and the ninth positive power spherical lens are: (1.3, 1.65), (1.3, 1.65), (1.8, 2.0) C3 、Vd C4 、Vd C5 are: (60,100), (60,100), (15,40).

[0019] The second negative power lens group is a moving group, and its moving amount formula is: ΔB W→T / TTL∈(0.2,0.28), where: ΔB W→T is the relative displacement of the front vertex of the third negative power spherical lens in the second negative power lens group at the wide-angle end and the telephoto end, and TTL is the total length of the optical system.

[0020] The third positive power lens group is a moving group, and its moving amount formula is: ΔC W→T / TTL∈(0.07,0.20), where: ΔC W→T is the relative displacement of the front vertex of the fifth positive power aspherical lens in the third positive power lens group at the wide-angle end and the telephoto end, and TTL is the total length of the optical system.

[0021] The aspheric formula of all aspheric lenses of the present invention is expressed as follows:

[0022]

[0023] Among them, Z is the distance vector height sag from the vertex of the aspherical surface when the height of the aspherical surface along the optical axis is h, R is the radius of curvature of the mirror surface, K is the cone coefficient conic, A, B, C, D, E, F are high-order aspherical coefficients, and the e in the coefficient represents the scientific number sign, such as e-005.

[0024] Technical Effects

[0025] Compared with the prior art, the present invention has the following technical effects:

[0026] 1. The four-group and three-group linkage zoom structure is adopted to realize a wide-angle zoom photography system at a fixed length, which is convenient for installation in actual use;

[0027] 2. Using the negative group as the focus reduces the total length of the system, and the front diameter of the lens is also reduced, which is not only convenient for installation, but also convenient for carrying, without losing the aperture and target size;

[0028] 3. The use of three aspherical surfaces in coordination with the movement of the group achieves a resolution of 20 million, and the resolution is uniform from the center to the edge of the picture. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the intermediate magnification optical path diagram of Example 1 of the present invention;

[0030] Figure 2 This is a telephoto optical path diagram of Example 1 of the present invention;

[0031] Figure 3 This is the wide-angle end optical path diagram of Embodiment 1 of the present invention;

[0032] Figure 4 This is the intermediate magnification spherical aberration diagram of Example 1 of the present invention;

[0033] Figure 5 This is a spherical aberration diagram at the telephoto end of Example 1 of the present invention;

[0034] Figure 6 This is a spherical aberration diagram at the wide-angle end of Example 1 of the present invention;

[0035] Figure 7 This is the intermediate magnification optical path diagram of Example 2 of the present invention;

[0036] Figure 8 This is a telephoto optical path diagram of Embodiment 2 of the present invention;

[0037] Fig. 9 This is the wide-angle end optical path diagram of Embodiment 2 of the present invention;

[0038] Fig.10 This is the intermediate magnification spherical aberration diagram of Example 2 of the present invention;

[0039] Fig.11 This is a spherical aberration diagram at the telephoto end of Example 2 of the present invention;

[0040] Fig.12 This is a spherical aberration diagram at the wide-angle end of Example 2 of the present invention;

[0041] In the figure: a first positive power lens group 1, a second negative power lens group 2, a third positive power lens group 3, a fourth negative power lens group 4, a filter 5, an imaging surface 6, an aperture 7, a first positive power spherical lens 8, a second negative power spherical lens 9, a third negative power spherical lens 10, a fourth positive power aspherical lens 11, a fifth positive power aspherical lens 12, a sixth positive power spherical lens 13, a seventh negative power spherical lens 14, an eighth positive power aspherical lens 15, a ninth positive power spherical lens 16, a tenth negative power spherical lens 17, an eleventh aspherical lens 18, and a twelfth spherical lens 19. DETAILED DESCRIPTION

[0042] like Figure 1 As shown, a wide-angle full-length fixed zoom photography lens for a robot involved in this embodiment comprises: a first positive power lens group 1, a second negative power lens group 2, a third positive power lens group 3, a fourth negative power lens group 4, a filter 5 for passing visible light or infrared light, and an imaging surface 6, which are arranged in sequence from the object surface side to the image surface side, wherein: the first positive power lens group 1 is always in a fixed state, and the second negative power lens group 2 moves along the optical axis from the object side to the image surface side, and the third positive power lens group 3 moves along the optical axis from the image surface side to the object side as a zoom group, so that the field angle of the lens is zoomed from the wide-angle end to the telephoto end, and at the same time, the fourth negative power lens group 4 is made to move along the optical axis in a nonlinear manner with a specific functional relationship with the position, imaging wavelength, temperature, and imaging object distance of the second negative power lens group 2 and the third positive power lens group 3 as a focusing group, so that the image surface change accompanying the zoom is corrected and focused, so as to ensure the stability of the system image surface during the focal length change process.

[0043] A stop 7 is disposed inside the third positive power lens group 3 .

[0044] The first positive power lens group 1 comprises: first positive power spherical lenses 8 arranged in sequence from the object side along the optical axis.

[0045] The second negative power lens group 2 comprises: a second negative power spherical lens 9, a third negative power spherical lens 10 and a fourth positive power aspherical lens 11 which are arranged in sequence from the object side along the optical axis.

[0046] The third positive power lens group 3 includes: a fifth positive power aspheric lens 12, a sixth positive power spherical lens 13 and a seventh negative power spherical lens 14 which can be glued into a doublet lens, as well as an eighth positive power aspheric lens 15 and a ninth positive power spherical lens 16 which are arranged in sequence from the object side along the optical axis, wherein the fifth positive power aspheric lens 12 and the sixth positive power spherical lens 13 are arranged on both sides of the aperture 7.

[0047] The fourth negative power lens group 4 comprises: a tenth negative power spherical lens 17 arranged in sequence from the object side along the optical axis, and the minimum distance between the lens 17 and the filter 5 is 3.15 mm.

[0048] The imaging surface is provided with an imaging receiving surface of a solid-state imaging element of CCD or CMOS.

[0049] The specific configuration of the zoom optical system in this embodiment is as follows:

[0050] The wide-angle focal length f W =9mm, telephoto focal length f T =36mm, wide-angle aperture number FNO W =1.80, FNO at telephoto end T =4.0, half field of view at wide angle ω W =42.5°, half field of view angle at telephoto endω T =12.2°, the total optical length of the optical system (i.e. the distance from the central vertex of the front surface of the first positive power spherical lens 8 to the image plane) TTL=99.7mm.

[0051] Table 1: Those with * are aspherical surfaces:

[0052]

[0053]

[0054] The corresponding conic coefficient (K) and aspheric coefficients (A, B, C, D, E) of the aspheric lens are as follows:

[0055] Table 2:

[0056]

[0057] The zoom data at the wide angle end, the middle magnification position, and the telephoto end are as follows:

[0058] Table 3:

[0059]

[0060] The ratio f of the focal length of the first positive power lens group 1, the second negative power lens group 2, the third positive power lens group 3 and the fourth negative power lens group 4 to the focal length of the entire optical system at the wide angle end is A / f W 、f B / f W 、f C / f W 、f D / f W They are: 14.78, -2.21, 2.22, and -1.59 respectively.

[0061] The ratio f of the focal length of the second negative power spherical lens 9, the third negative power spherical lens 10 and the fourth positive power aspherical lens 11 to the focal length of the second negative power lens group 2 is B1 / f B 、f B2 / f B 、f B3 / f B They are: 1.27, 1.52, and -2.36 respectively.

[0062] The ratio f of the focal length of the fifth positive power aspheric lens 12, the sixth positive power spherical lens 13, the seventh negative power spherical lens 14, the eighth positive power aspheric lens 15, and the ninth positive power spherical lens 16 to the focal length of the third positive power lens group 3 is C1 / f C 、f C2 / f C 、f C3 / f C 、f C4 / f C 、f C5 / f C The ratio f of the focal length of the double cemented lens to the focal length of the third positive power lens group 3 is: 1.01, 0.62, -0.31, 1.33, 0.68. C2C3 / f C is:-0.82.

[0063] The ratio L of the distance from the position of the aperture 7 to the left side of the fifth positive power aspheric lens 12 of the third positive power lens group 3 to the total optical length of the third positive power lens group 3 is: S-L1 / L C is: 0.43, to limit the size of the aperture.

[0064] The refractive index Nd of the first positive power spherical lens 8 is A1 is: 1.49700, Abbe number Vd A1 It is:81.61.

[0065] The refractive index Nd of the fourth positive power aspheric lens 11 is B3 is: 1.94595, Abbe number Vd B3 Is: 17.98.

[0066] The refractive index Nd of the fifth positive power aspheric lens 12, the eighth positive power aspheric lens 15 and the ninth positive power spherical lens 16 is C3 、Nd C4 、Nd C4 The Abbe numbers Vd of the seventh negative power spherical lens 14 and the ninth positive power spherical lens 16 are: 1.49700, 1.49700, 1.80518. C3 、Vd C4 、Vd C5 It is: 81.61, 81.61, 25.46.

[0067] The ratio of the movement distance of the second negative optical power lens group 2 from the wide angle end of the optical system to the telephoto end of the optical system to the total optical length of the optical system is ΔB. W→T / TTL is: 0.25, where: ΔB W→T is the relative displacement of the front vertex of the second negative power spherical lens 9 in the second negative power lens group 2 at the wide-angle end position and the telephoto end position, and TTL is the total optical length of the optical system (i.e., the distance from the central vertex of the front surface of the first lens to the image plane).

[0068] The ratio of the movement amount of the third positive power lens group 3 from the wide angle end of the optical system to the telephoto end of the optical system to the total optical power of the optical system is ΔC. W→T / TTL is: 0.13, where: ΔC W→T is the relative displacement of the front vertex of the fifth positive power aspherical lens 12 at the wide-angle end position and the telephoto end position, and TTL is the total length of the optical system.

[0069] Example 2

[0070] like Figure 7 As shown, it is a schematic diagram of the cross-section of the structure at the wide-angle end, the intermediate magnification, and the telephoto end of the second embodiment. The basic structure is the same as that of the first embodiment, except that:

[0071] The second negative optical power spherical lens 12 is realized by the eleventh aspherical lens 18 and the twelfth spherical lens 19 and achieves a similar effect.

[0072] The specific configuration of the zoom optical system in this embodiment is as follows:

[0073] Wide-angle focal length f W =8mm, telephoto focal length f T=32mm; wide-angle aperture number FNO W =1.75, FNO at telephoto end T =4.0; half field of view at wide angle ω W =43.0°, half field of view angle at telephoto endω T =12.0°; the total optical length of the optical system (i.e. the distance from the central vertex of the front surface of the first lens to the image plane) TTL = 88.8 mm.

[0074] Table 4: Those with * are aspherical surfaces:

[0075]

[0076]

[0077] The corresponding cone coefficient (K) and aspheric coefficients (A, B, C, D, E) of the aspheric lens used in this embodiment are as follows:

[0078] Table 5:

[0079]

[0080] The zoom data at the wide-angle end, the middle magnification position, and the telephoto end are as follows:

[0081] Table 6:

[0082]

[0083]

[0084] The ratio f of the focal length of the first positive power lens group 1, the second negative power lens group 2, the third positive power lens group 3 and the fourth negative power lens group 4 to the focal length of the entire optical system at the wide angle end is A / f W 、f B / f W 、f C / f W 、f D / f W They are: 10.51, -1.92, 2.03, and -1.20 respectively.

[0085] The ratio f of the focal length of the first positive power spherical lens 8 to the focal length of the first positive power lens group 1 is A1 / f A is: 1.0.

[0086] The ratio f of the focal length of the second negative power spherical lens 2, the third negative power spherical lens 3 and the fourth positive power aspherical lens 4 to the focal length of the second negative power lens group 2 is B1 / fB 、f B2 / f B 、f B3 / f B They are: 1.62, 1.88, and -1.88 respectively.

[0087] The ratio f of the focal length of the sixth positive power spherical lens 13, the seventh negative power spherical lens 17, the eighth positive power aspherical lens 18, and the ninth positive power spherical lens 19 to the focal length of the third positive power lens group 3 is C3 / f C 、f C4 / f C 、f C5 / f C 、f C6 / f C The ratio f of the focal length of the double-cemented lens formed by the seventh negative power spherical lens 17 and the eighth positive power aspherical lens 18 to the focal length of the third positive power lens group 3 is: 0.66, -0.38, 1.43, 0.81, respectively. C2C3 / f C = -0.99, the ratio of the focal length of the eleventh aspherical lens 18 and the twelfth spherical lens 19 to the focal length of the entire C lens group is f C1C2 / f C is: 1.05.

[0088] The ratio L of the distance from the position of the aperture 7 to the optical first surface of the third positive power lens group 3 to the total optical length of the third positive power lens group 3 is S-L1 / L C Is: 0.48.

[0089] The refractive index Nd of the first positive power spherical lens 8 is A1 is: 1.43700, Abbe number Vd A1 Is: 95.10.

[0090] The refractive index Nd of the fourth positive power aspheric lens 11 is B3 is: 1.92286, Abbe number Vd B3 Is: 20.88.

[0091] The refractive index Nd of the sixth positive power aspheric lens 13, the eighth positive power aspheric lens 15 and the ninth positive power spherical lens 16 is C2 、Nd C4 、Nd C5 The Abbe numbers Vd of the seventh negative power spherical lens 14 and the ninth positive power spherical lens 16 are: 1.43700, 1.49700, 1.84666 C2 、VdC4 、Vd C5 They are: 95.10, 81.61, 23.78.

[0092] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A wide-angle, full-length, fixed zoom camera lens for robots, characterized in that: include: A first positive power lens group, a second negative power lens group, a third positive power lens group, a fourth negative power lens group, a filter for passing visible light and infrared light, and an imaging surface are arranged in sequence from the object plane side to the image plane side, wherein: an aperture is provided in the third positive power lens group; The second negative power lens group moves along the optical axis from the object side to the image side, and the third positive power lens group moves along the optical axis from the image side to the object side as a zoom group, so that the lens field angle is zoomed from the wide angle end to the telephoto end. The first positive power lens group comprises: a plurality of first positive power spherical lenses arranged in sequence from the object side along the optical axis; The second negative power lens group comprises: a plurality of second negative power spherical lenses, a third negative power spherical lens and a fourth positive power aspherical lens arranged in sequence from the object side along the optical axis; The fourth negative power lens group comprises: a plurality of tenth negative power spherical lenses arranged in sequence from the object side along the optical axis; The third positive power lens group comprises: a plurality of fifth positive power aspheric lenses, a sixth positive power spherical lens and a seventh negative power spherical lens which can be glued together into a doublet lens, and an eighth positive power aspheric lens and a ninth positive power spherical lens which are sequentially arranged along the optical axis from the object side, wherein: the fifth positive power aspheric lens and the sixth positive power spherical lens are arranged on both sides of the aperture stop; The second negative power lens group is a moving group, and its moving amount formula is: ΔBW→T / TTL∈(0.2,0.28), where: ΔBW→T is the relative displacement of the front vertex of the third negative power spherical lens in the second negative power lens group at the wide-angle end position and the telephoto end position, and TTL is the total length of the optical system; The third positive power lens group is a moving group, and its movement formula is: ΔCW→T / TTL∈(0.07,0.20), where: ΔCW→T is the relative displacement of the front vertex of the fifth positive power aspheric lens in the third positive power lens group at the wide-angle end position and the telephoto end position, and TTL is the total length of the optical system.

2. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The second negative optical power spherical lens is realized by an eleventh aspherical lens and a twelfth spherical lens.

3. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The ratio of the focal length of the first positive power lens group to the focal length at the wide angle end is f A / f W is (8,12); the ratio of the focal length of the second negative power lens group to the focal length of the wide angle end is f B / f W is (-2.5, -0.5); the ratio of the focal length of the third positive power lens group to the focal length of the wide angle end is f C / f W is (1.5,3.5); the ratio of the focal length of the fourth negative focal power lens group to the focal length at the wide angle end is f D / f W is (-3.5,-1.5).

4. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The ratio f of the focal length of the first positive power spherical lens to the focal length of the first positive power lens group is A1 / f A is: (0.5,1.0).

5. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The ratio f of the focal length 11 of the second negative power spherical lens, the third negative power spherical lens and the fourth positive power aspherical lens to the focal length of the second negative power lens group is B1 / f B 、f B2 / f B 、f B3 / f B They are: (0.9, 1.77), (0.9, 1.77), (-2.77, -1.75) respectively.

6. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The ratio f of the focal length of the fifth positive power aspheric lens, the sixth positive power spherical lens, the seventh negative power spherical lens, the eighth positive power aspheric lens, the ninth positive power spherical lens to the focal length of the third positive power lens group is C1 / f C 、f C2 / f C 、f C3 / f C 、f C4 / f C 、f C5 / f C They are: (0.88, 1.1), (0.55, 0.7), (-0.42, -0.21), (1.19, 1.55), (0.58, 0.97), the ratio of the focal length of the double cemented lens to the focal length of the third positive power lens group f C2C3 / f C is: (-1.05,-0.64).

7. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The iris is a variable iris, and its position is: L S-L1 / L C ∈(0.39,0.55), where: L S-L1 L is the distance from the aperture 7 to the first optical surface of the third positive power lens group. C is the total optical length of the third positive power lens group.

8. The wide-angle, full-length, fixed zoom camera lens for robots according to claim 1, characterized in that: The refractive index Nd of the first positive power spherical lens is A1 is: (1.3, 1.65), Abbe number Vd A1 is: (60,100); The refractive index Nd of the fourth positive power aspheric lens is B3 is: (1.8, 2.0), Abbe number Vd B3 is: (15,40); The refractive index Nd of the fifth positive power aspheric lens, the eighth positive power aspheric lens and the ninth positive power spherical lens is C3 、Nd C4 、Nd C4 The Abbe numbers Vd of the seventh negative power spherical lens and the ninth positive power spherical lens are: (1.3, 1.65), (1.3, 1.65), (1.8, 2.0) C3 、Vd C4 、Vd C5 are: (60,100), (60,100), (15,40).

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