Glass-plastic hybrid lens

Abstract

The present invention relates to a glass-plastic hybrid lens, comprising 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) and an eighth lens (8) arranged in sequence from the object side to the image side along an optical axis, characterized in that the first lens (1), the second lens (2), the fourth lens (4) and the seventh lens (7) are negative power lenses; and the third lens (3), the fifth lens (5), the sixth lens (6) and the eighth lens (8) are positive power lenses. The glass-plastic hybrid lens of the present invention has the advantages of large aperture and high pixel.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging, and in particular to a glass-plastic hybrid lens. Background Art

[0002] With the rapid development of science and technology, people have higher requirements for security, and the demand for surveillance lenses has also arisen. Compared with zoom lenses, fixed-focus lenses are simpler in design and manufacturing. The images of moving objects taken are clear and stable, the pictures are delicate, and they can be shot 24 hours a day. These properties play a very important role in the field of security lenses. There is no sunlight at night, and small aperture lenses can only be used at night with infrared fill light. Therefore, in order to solve the above problems, it is necessary to design a lens that can be used both day and night with a large aperture, large light transmission, and no infrared. Summary of the invention

[0003] The purpose of the present invention is to solve the above-mentioned problem and provide a glass-plastic hybrid lens with a large aperture.

[0004] To achieve the above-mentioned object of the present invention, the present invention provides a glass-plastic hybrid lens, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens arranged in sequence from the object side to the image side along the optical axis, wherein the first lens, the second lens, the fourth lens and the seventh lens are negative power lenses;

[0005] The third lens, the fifth lens, the sixth lens and the eighth lens are positive power lenses.

[0006] According to one aspect of the present invention, the fourth lens and the fifth lens form a doublet lens with positive refractive power.

[0007] According to one aspect of the present invention, the focal length fb of the doublet lens composed of the fourth lens and the fifth lens and the effective focal length f of the glass-plastic hybrid lens satisfy the relationship: fb / f≥1.5.

[0008] According to one aspect of the present invention, along the direction from the object side to the image side, the first lens is a convex-concave lens, the second lens is a lens concave toward the object side, the third lens is a lens with a convex surface on the object side, the fourth lens is a convex-concave lens, the fifth lens is a convex-convex lens, the sixth lens is a convex-convex lens, the seventh lens is a concave-concave lens, and the eighth lens is a convex-convex lens.

[0009] According to one aspect of the present invention, the first lens is a spherical or aspherical lens, the second lens is an aspherical lens, the third lens is an aspherical lens, the fourth lens is a spherical lens, the fifth lens is a spherical lens, the sixth lens is an aspherical lens, the seventh lens is an aspherical lens, and the eighth lens is an aspherical lens.

[0010] According to one aspect of the present invention, all aspherical lenses in the glass-plastic hybrid lens satisfy the relationship:

[0011]

[0012] Where z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the cone coefficient; A4, A6, A8, A 10 , A 12 , A 14 , A 16 ···represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order···aspheric coefficients respectively.

[0013] According to one aspect of the present invention, at least one of the first lens, the fourth lens and the fifth lens has a refractive index Nd≥1.6 and an Abbe number coefficient Vd≥50.

[0014] According to one aspect of the present invention, the focal length f3 of the third lens and the effective focal length f of the glass-plastic hybrid lens satisfy the relationship: 1.5≤f3 / f≤8.

[0015] According to one aspect of the present invention, the refractive index Nd3 of the third lens is ≥1.6, and the Abbe number coefficient Vd3 is ≤30.

[0016] According to one aspect of the present invention, the refractive index Nd8 of the eighth lens is ≥1.5, and the Abbe number coefficient Vd8 is ≥50.

[0017] According to one aspect of the present invention, the focal power of the seventh lens and the focal power of the sixth lens or the eighth lens satisfy the relationship: 2≥|φ7 / φ6|≥1.05 or 2≥|φ7 / φ8|≥1.05;

[0018] φ7 represents the optical power of the seventh lens, φ6 represents the optical power of the sixth lens, and φ8 represents the optical power of the eighth lens.

[0019] According to one aspect of the present invention, the glass-plastic hybrid lens further includes an aperture stop, which is located between the second lens and the third lens, or between the third lens and the fourth lens, or between the fifth lens and the sixth lens.

[0020] According to one aspect of the present invention, the aperture number Fno of the glass-plastic hybrid lens is ≤1.2.

[0021] According to one aspect of the present invention, the chief ray deviation angle CRA of the glass-plastic hybrid lens is ≤15°.

[0022] According to one aspect of the present invention, the total length of the optical system of the glass-plastic hybrid lens is ≤25 mm.

[0023] The lens of the present invention adopts a common setting form of a non-spherical lens made of plastic material and a spherical lens made of glass material, which reduces the production cost of the lens of the present invention. The lens of the present invention can achieve a large aperture, meet the requirements of high-pixel image output, and ensure high resolution under a large aperture. The lens of the present invention optimizes the configuration of the positive and negative focal lengths of each lens to effectively correct the aberration; the overall illumination of the lens of the present invention is uniform and the brightness is high (relative illumination is more than 45%). The lens of the present invention can achieve no defocusing in the temperature range of -40°C to 85°C, and overcomes the difficulty that the plastic aspherical lens is easy to cause focus drift in high and low temperature environments due to its large expansion coefficient. The lens of the present invention can achieve confocal imaging in the range of visible light band to infrared light band. The single component and assembly tolerance of the lens of the present invention are good, and it has good manufacturability. The CRA of the lens of the present invention is ≤15°, and it can be adapted to a variety of sensors, with broad application prospects and improved market competitiveness. The total length of the head of the lens of the present invention is within 25mm and the volume is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The structure diagram of the glass-plastic hybrid lens according to Embodiment 1 of the present invention is schematically shown;

[0025] Figure 2 The MTF diagram of the glass-plastic hybrid lens according to Example 1 of the present invention is schematically shown;

[0026] Figure 3 Schematically showing a Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 1 of the present invention at a frequency of 240lp / mm;

[0027] Figure 4 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 1 of the present invention at a high temperature of 80° C. and a frequency of 120 lp / mm;

[0028] Figure 5 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 1 of the present invention at a low temperature of -40°C and a frequency of 120lp / mm;

[0029] Figure 6A schematic diagram schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 2 of the present invention;

[0030] Figure 7 Schematically showing the MTF diagram of the glass-plastic hybrid lens according to Example 2 of the present invention;

[0031] Figure 8 Schematically showing a Through-Focus-MTF diagram of a glass-plastic hybrid lens according to Example 2 of the present invention at a frequency of 240lp / mm;

[0032] Fig. 9 A schematic diagram of the Through-Focus-MTF of the glass-plastic hybrid lens according to Example 2 of the present invention at a high temperature of 80° C. and a frequency of 120 lp / mm is shown;

[0033] Fig.10 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 2 of the present invention at a low temperature of -40°C and a frequency of 120lp / mm;

[0034] Fig.11 A schematic diagram schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 3 of the present invention;

[0035] Fig.12 Schematically showing the MTF diagram of the glass-plastic hybrid lens according to Example 3 of the present invention;

[0036] Fig.13 Schematically showing a Through-Focus-MTF diagram of a glass-plastic hybrid lens according to Example 3 of the present invention at a frequency of 240lp / mm;

[0037] Fig.14 Schematically showing a Through-Focus-MTF diagram of a glass-plastic hybrid lens according to Example 3 of the present invention at a high temperature of 80° C. and a frequency of 120 lp / mm;

[0038] Fig.15 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 3 of the present invention at a low temperature of -40°C and a frequency of 120lp / mm;

[0039] Fig.16 A schematic diagram schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 4 of the present invention;

[0040] Fig.17 Schematically showing the MTF diagram of the glass-plastic hybrid lens according to Example 4 of the present invention;

[0041] Fig.18Schematically showing a Through-Focus-MTF diagram of a glass-plastic hybrid lens according to Example 4 of the present invention at a frequency of 240 lp / mm;

[0042] Fig.19 The Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 4 of the present invention at a high temperature of 80° C. and a frequency of 120 lp / mm is schematically shown;

[0043] Fig. 20 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 4 of the present invention at a low temperature of -40°C and a frequency of 120lp / mm;

[0044] Fig.21 A schematic diagram schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 5 of the present invention;

[0045] Fig. 22 Schematically showing the MTF diagram of the glass-plastic hybrid lens according to Example 5 of the present invention;

[0046] Fig.23 Schematically showing a Through-Focus-MTF diagram of a glass-plastic hybrid lens according to Example 5 of the present invention at a frequency of 240lp / mm;

[0047] Fig.24 Schematically showing the Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 5 of the present invention at a high temperature of 80° C. and a frequency of 120 lp / mm;

[0048] Fig.25 The Through-Focus-MTF diagram of the glass-plastic hybrid lens according to Example 5 of the present invention at a low temperature of -40°C and a frequency of 120 lp / mm is schematically shown. DETAILED DESCRIPTION

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] When describing the embodiments of the present invention, the orientation or positional relationship expressed by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0051] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments cannot be described one by one here, but the embodiments of the present invention are not therefore limited to the following embodiments.

[0052] Figure 1 Schematically shows the structure of a glass-plastic hybrid fixed-focus lens according to an embodiment of the present invention. Figure 1 As shown, the glass-plastic hybrid fixed-focus lens of the present invention is composed of a glass lens and a plastic lens, including: 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 and an eighth lens 8 arranged in sequence from the object side to the image side along the optical axis. In the present invention, the first lens 1, the second lens 2, the fourth lens 4 and the seventh lens 7 are negative optical focal length lenses, and the third lens 3, the fifth lens 5, the sixth lens 6 and the eighth lens 8 are positive optical focal length lenses. In addition, in the present invention, the fourth lens 4 and the fifth lens 5 form a double-cemented lens with positive optical focal length, and the focal length fb of the double-cemented lens composed of the fourth lens 4 and the fifth lens 5 satisfies the relationship f of the effective focal length f of the glass-plastic hybrid lens: fb / f≥1.5. By setting the positive and negative optical focal lengths of each lens in this way, the aberration is effectively corrected, while ensuring the large aperture and high pixel of the glass-plastic hybrid lens of the present invention.

[0053] In the present invention, along the direction from the object side to the image side, the first lens 1 is a convex-concave lens, the second lens 2 is a lens concave toward the object side, the third lens) is a lens with a convex surface on the object side, the fourth lens 4 is a convex-concave lens, the fifth lens 5 is a convex-convex lens, the sixth lens 6 is a convex-convex lens, the seventh lens 7 is a concave-concave lens, and the eighth lens 8 is a convex-convex lens.

[0054] In the present invention, the first lens 1 is a spherical or aspherical lens, the second lens 2 is an aspherical lens, the third lens 3 is an aspherical lens, the fourth lens 4 is a spherical lens, the fifth lens 5 is a spherical lens, the sixth lens 6 is an aspherical lens, the seventh lens 7 is an aspherical lens, and the eighth lens 8 is an aspherical lens. According to one embodiment of the present invention, the aspherical lens of the lens of the present invention is set as a plastic lens, and the spherical lens is set as a glass lens.

[0055] All aspherical surfaces in the lens of the present invention satisfy the following formula:

[0056]

[0057] Where z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the cone coefficient; A4, A6, A8, A 10 , A 12 , A 14 , A 16 ···represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order···aspheric coefficients respectively.

[0058] The lens set as above reduces production costs and can achieve non-defocusing in the temperature range of -40℃ to 85℃, overcoming the difficulty of focus drift caused by plastic aspheric lenses due to their large expansion coefficient in high and low temperature environments. In addition, the single component and assembly tolerances are good, and the manufacturability is good.

[0059] In addition, in the lens of the present invention, the refractive index Nd of at least one of the first lens 1, the fourth lens 4 and the fifth lens 5 is ≥ 1.6, and the Abbe number coefficient Vd is ≥ 50. Such a setting is conducive to correcting the dispersion of the lens and improving the imaging quality.

[0060] In the present invention, the focal length f3 of the third lens 3 and the effective focal length f of the glass-plastic hybrid lens satisfy the relationship: 1.5≤f3 / f≤8. The refractive index Nd3≥1.6 and the Abbe number coefficient Vd3≤30 of the third lens 3. The refractive index Nd8≥1.5 and the Abbe number coefficient Vd8≥50 of the eighth lens 8.

[0061] In the present invention, the focal power of the seventh lens 7 and the focal power of the sixth lens 6 or the eighth lens 8 satisfy the relationship: 2≥|φ7 / φ6|≥1.05 or 2≥|φ7 / φ8|≥1.05; φ7 represents the focal power of the seventh lens 7, φ6 represents the focal power of the sixth lens 6, and φ8 represents the focal power of the eighth lens 8.

[0062] The glass-plastic hybrid lens of the present invention further comprises an aperture S, which is located between the second lens 2 and the third lens 3, or between the third lens 3 and the fourth lens 4, or between the fifth lens 5 and the sixth lens 6. The glass-plastic hybrid lens of the present invention has an aperture number Fno≤1.2, a chief ray deflection angle CRA≤15°, and a total length of the optical system≤25 mm.

[0063] Combining the above settings, the lens of the present invention can achieve a large aperture and meet the requirements of high-pixel image output, ensuring high resolution at a large aperture. In addition, the overall illumination of the lens of the present invention is uniform and the brightness is high (relative illumination is more than 45%). In addition, the lens of the present invention can achieve confocal imaging in the range of visible light band to infrared light band, can be non-defocused in the temperature range of -40℃-80℃, and has a wide range of applicable environments. The chief light deflection angle CRA of the lens of the present invention is ≤15°, and it can be adapted to a variety of sensors, with broad application prospects. The market angle of the lens of the present invention can reach 150°, and the total length of the optical system is within 25mm, which is conducive to the miniaturization of the lens.

[0064] Five groups of specific implementations are given below based on the above-mentioned configuration of the present invention to specifically illustrate the glass-plastic hybrid lens according to the present invention. Because the glass-plastic hybrid lens according to the present invention has a total of eight lenses, the fourth lens 4 and the fifth lens 5 are cemented to form a double cemented lens, plus the aperture S, the imaging surface IMA of the lens, and the surface of the flat filter IR between the imaging surface IMA and the lens, a total of 19 surfaces. For the convenience of description, the surfaces are numbered from S1 to S19.

[0065] The data of five groups of implementation methods are as shown in Table 1 below:

[0066]

[0067] Table 1

[0068] Implementation method 1:

[0069] Figure 1 Schematically shows the structure of a glass-plastic hybrid lens according to the first embodiment of the present invention.

[0070] In the first embodiment, the aperture FNO=1.0, the total length of the lens optical system is 23.769 mm, and the field of view angle is 150°.

[0071] Table 2 below lists the relevant parameters of each lens of this embodiment, including surface type, radius of curvature, thickness, refractive index of the material, and Abbe number:

[0072]

[0073]

[0074] Table 2

[0075] In this embodiment, the aspheric surface data are shown in Table 3 below, where K is the quadratic surface constant of the surface, and A, B, C, D, E, F, and G are the aspheric surface coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order, respectively:

[0076] Surface number K A B C D E F G S1 -5.20E-01 7.43E-03 -5.58E-04 7.23E-05 1.90E-07 8.44E-08 0 0 S2 -5.7E+00 6.14E-03 -3.58E-04 -3.02E-07 2.75E-06 -6.87E-08 0 0 S3 -3.01E-01 8.43E-03 -5.58E-04 8.05E-05 -4.37E-06 9.44E-08 0 0 S4 -1.72E+00 5.14E-03 -4.05E-04 -3.32E-07 1.73E-06 -7.87E-08 0 0 S5 -6.88E-02 -5.54E-04 1.78E-04 -1.40E-05 6.74E-07 -1.41E-08 0 0 S6 5.67E-01 -2.50E-04 1.93E-04 -6.25E-06 1.90E-07 -4.03E-09 0 0 S11 -2.86E-02 -1.48E-03 3.63E-05 -1.08E-05 9.15E-08 4.55E-09 0 0 S12 9.59E+01 -1.55E-03 2.59E-05 1.65E-06 -1.75E-07 5.73E-09 0 0 S13 -2.98E+00 -1.47E-04 1.90E-04 -4.43E-06 9.62E-08 6.55E-11 0 0 S14 5.18E-01 -1.20E-03 6.51E-04 -1.43E-05 -1.15E-07 -2.82E-08 0 0 S15 -5.56E-01 -2.23E-03 3.65E-04 7.45E-06 -3.44E-08 -4.44E-08 0 0 S16 -6.30E+00 6.60E-04 -1.63E-04 1.14E-05 -8.82E-07 1.09E-09 0 0

[0077] Table 3

[0078] Figures 2 to 5 The MTF diagrams of the glass-plastic hybrid lens according to the first embodiment of the present invention are schematically represented respectively; the Through-Focus-MTF diagram with a frequency of 240lp / mm; the Through-Focus-MTF diagram with a frequency of 120lp / mm at a high temperature of 80°C and the Through-Focus-MTF diagram with a frequency of 120lp / mm at a low temperature of -40°C.

[0079] Depend on Figures 2 to 5 It can be seen that the lens of this embodiment achieves the characteristics of high resolution and high pixel, and takes into account the characteristics of day and night confocality and no out-of-focus in the temperature range of -40°C to 85°C, while meeting the large aperture and expanding the scope of use of the product.

[0080] Implementation method 2:

[0081] Figure 6 Schematically shows the structure of a glass-plastic hybrid lens according to the second embodiment of the present invention.

[0082] In the second embodiment, the aperture FNO=1.1, the total length of the lens optical system is 23.00 mm, and the field of view angle is 140°.

[0083] Table 4 below lists the relevant parameters of each lens of this embodiment, including surface type, radius of curvature, thickness, refractive index of the material, and Abbe number:

[0084] Surface number Surface type R-Value thickness Refractive Index Abbe number S0(OBJ) Spherical Infinity Infinity S1 Spherical 31.0159 0.7036 1.62 57.0 S2 Spherical 4.3370 3.2875 S3 Aspheric -4.7889 1.2064 1.53 56.0 S4 Aspheric -8.2934 0.15687 S5(STO) Spherical Infinity 0.0234 S6 Aspheric 11.7236 2.8926 1.66 20.4 S7 Aspheric 15.1423 0.8934 S8 Spherical 17.6762 0.8346 2.00 28.3 S9 Spherical 9.5896 4.5675 1.65 60.4 S10 Spherical -8.5649 0.3689 S11 Aspheric 7.8521 1.2014 1.66 20.4 S12 Aspheric -20.0121 0.0536 S13 Aspheric -9.0145 0.6871 1.54 55.9 S14 Aspheric 2.1356 0.8912 S15 Aspheric 5.2136 1.3596 1.52 56.2 S16 Aspheric -17.1369 0.1 S17 Spherical Infinity 0.8 1.52 64.2 S18 Spherical Infinity 3.7569 S19(IMA) Spherical Infinity - - -

[0085] Table 4

[0086] In this embodiment, the aspheric surface data are shown in Table 5 below, where K is the quadratic surface constant of the surface, and A, B, C, D, E, F, and G are the aspheric surface coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order, respectively:

[0087] Surface number K A B C D E F G S3 -1.78E-02 1.01E-02 -6.50E-04 4.42E-05 -1.20E-06 -2.28E-09 0 0 S4 -1.66E-02 6.09E-03 -2.43E-02 -2.29E-06 1.19E-07 4.15E-10 0 0 S6 7.56E-01 -8.71E-03 2.06E-03 -1.35E-04 3.48E-07 -1.84E-09 0 0 S7 4.44E-03 -4.95E-03 2.27E-04 -5.45E-04 1.78E-08 -1.53E-09 0 0 S11 -5.29E-03 -1.55E-02 5.84E-05 -9.63E-06 1.43E-03 1.97E-11 0 0 S12 1.24E+00 -1.36E-03 1.75E-04 1.96E-03 -9.49E-08 4.28E-10 0 0 S13 5.62E-02 -3.95E-03 1.59E-03 -6.57E-06 1.29E-07 1.01E-09 0 0 S14 1.73E-02 -5.81E-02 6.65E-03 -2.06E-04 2.33E-08 -8.85E-10 0 0 S15 5.42E-01 -6.20E-02 4.18E-02 3.46E-06 -6.40E-07 -8.67E-10 0 0 S16 1.07E+00 8.49E-02 -8.14E-05 1.20E-04 -4.65E-07 -4.01E-09 0 0

[0088] Table 5

[0089] Figures 7 to 10 The MTF diagram of the glass-plastic hybrid lens according to embodiment 2 of the present invention, the Through-Focus-MTF diagram at a frequency of 240lp / mm, the Through-Focus-MTF diagram at a high temperature of 80°C and a Through-Focus-MTF diagram at a low temperature of -40°C and a frequency of 120lp / mm are schematically represented respectively.

[0090] Depend on Figures 7 to 10 It can be seen that the lens of this embodiment achieves the characteristics of high resolution and high pixel, and takes into account the characteristics of day and night confocality and no out-of-focus in the temperature range of -40°C to 85°C, while meeting the large aperture and expanding the scope of use of the product.

[0091] Implementation method three:

[0092] Fig.11 Schematically shows the structure of a glass-plastic hybrid lens according to the third embodiment of the present invention.

[0093] In the third embodiment, the aperture FNO=1.2, the total length of the lens optical system is 24.00 mm, and the field of view angle is 130°.

[0094] Table 6 below lists the relevant parameters of each lens of this embodiment, including surface type, radius of curvature, thickness, refractive index of the material, and Abbe number:

[0095] Surface number Surface type R-Value thickness Refractive Index Abbe number S0(OBJ) Spherical Infinity Infinity S1 Spherical 31.7601 0.7082 1.61 60.7 S2 Spherical 2.3345 3.4308 S3 Aspheric -4.7043 1.1325 1.53 56.0 S4 Aspheric -8.2900 0.1328 S5 Aspheric 10.5643 2.5648 1.66 20.4 S6 Aspheric -15.1423 0.7891 S7 Spherical 20.6762 1.7928 1.74 27.8 S8 Spherical 8.5859 3.3654 1.73 54.7 S9 Spherical -12.5928 0.2156 S10(STO) Spherical Infinity 0.2015 S11 Aspheric 5.4746 3.5645 1.66 20.4 S12 Aspheric -25.3216 0.1963 S13 Aspheric -20.3976 1.5682 1.66 20.4 S14 Aspheric 4.5984 0.3369 S15 Aspheric 5.1356 1.8934 1.52 56.1 S16 Aspheric -14.1346 0.1 S17 Spherical Infinity 0.8 1.52 64.2 S18 Spherical Infinity 3.2698 S19(IMA) Spherical Infinity - - -

[0096] Table 6

[0097] In this embodiment, the aspheric surface data are shown in Table 7 below, where K is the quadratic surface constant of the surface, and A, B, C, D, E, F, and G are the aspheric surface coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order, respectively:

[0098] Surface number K A B C D E F G S3 -1.68E-02 1.01E-02 -6.50E-04 4.42E-05 -1.20E-01 -2.28E-09 0 0 S4 -1.66E-01 6.09E-03 -2.43E-04 -2.29E-06 1.19E-07 5.15E-10 0 0 S5 5.62E-03 -8.71E-03 2.06E-05 -1.35E-05 3.48E-07 -1.84E-09 0 0 S6 2.33E-01 -4.95E-03 2.27E-08 -5.45E-06 1.78E-08 -1.53E-09 0 0 S11 -1.29E-03 -1.55E-03 5.84E-05 -9.63E-06 1.43E-09 1.97E-11 0 0 S12 5.24E+00 -1.36E-03 1.75E-05 1.96E-07 -9.49E-08 4.28E-10 0 0 S13 6.45E-01 -3.95E-05 1.59E-04 -6.57E-06 1.29E-07 1.01E-09 0 0 S14 3.73E-02 -5.81E-03 6.65E-03 -2.06E-05 2.33E-08 -8.85E-10 0 0 S15 6.42E-02 -6.20E-03 4.18E-04 3.46E-06 -6.40E-07 -8.67E-10 0 0 S16 2.07E+00 8.49E-04 -8.14E-04 1.20E-05 -4.65E-07 -4.01E-09 0 0

[0099] Table 7

[0100] Figures 12 to 15 The MTF diagram of the glass-plastic hybrid lens according to embodiment 3 of the present invention, the Through-Focus-MTF diagram at a frequency of 240lp / mm, the Through-Focus-MTF diagram at a high temperature of 80°C and a Through-Focus-MTF diagram at a low temperature of -40°C and a frequency of 120lp / mm are schematically represented respectively.

[0101] Depend on Figures 12 to 15 It can be seen that the lens of this embodiment achieves the characteristics of high resolution and high pixel, and takes into account the characteristics of day and night confocality and no out-of-focus in the temperature range of -40°C to 85°C, while meeting the large aperture and expanding the scope of use of the product.

[0102] Implementation method 4:

[0103] Fig.16 Schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 4 of the present invention.

[0104] In the fourth embodiment, the aperture Fno=1.15, the total length of the lens optical system is 23.3 mm, and the field angle is 120°.

[0105] Table 8 below lists the relevant parameters of each lens of this embodiment, including surface type, radius of curvature, thickness, refractive index of the material, and Abbe number:

[0106]

[0107]

[0108] Table 8

[0109] In this embodiment, the aspheric surface data are shown in Table 9 below, where K is the quadratic surface constant of the surface, and A, B, C, D, E, F, and G are aspheric surface coefficients of the fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth order, respectively:

[0110] Surface number K A B C D E F G S3 -1.01E-01 2.53E-04 -9.58E-04 8.05E-05 -4.37E-06 9.44E-08 0 0 S4 -1.62E+00 6.14E-03 -6.52E-04 -7.32E-07 1.73E-06 -7.87E-08 0 0 S5 -5.48E-03 -8.54E-04 1.78E-04 -2.45E-05 6.74E-07 -1.41E-08 0 0 S6 2.56E-02 -3.50E-04 1.93E-04 -6.25E-06 3.45E-07 -4.03E-09 0 0 S11 -6.89E-03 -1.27E-03 5.63E-05 -1.08E-05 9.15E-08 5.64E-09 0 0 S12 8.98E+01 -1.55E-03 2.59E-03 1.65E-07 -2.75E-07 7.45E-09 0 0 S13 -5.69E+00 -1.47E-02 1.90E-04 -8.43E-06 9.62E-08 6.55E-11 0 0 S14 2.46E-01 -2.45E-03 6.51E-04 -1.43E-05 -1.15E-07 -2.82E-08 0 0 S15 -1.78E-01 -2.53E-03 3.65E-02 7.45E-06 -2.45E-08 -4.44E-03 0 0 S16 -2.89E+00 2.45E-03 -1.63E-04 2.14E-05 -8.82E-07 1.09E-09 0 0

[0111] Table 9

[0112] Figures 17 to 20 The MTF diagram of the glass-plastic hybrid lens according to embodiment 4 of the present invention, the Through-Focus-MTF diagram with a frequency of 240lp / mm, the Through-Focus-MTF diagram with a frequency of 120lp / mm at a high temperature of 80°C, and the Through-Focus-MTF diagram with a frequency of 120lp / mm at a low temperature of -40°C are schematically represented respectively.

[0113] Depend on Figures 17 to 20 It can be seen that the lens of this embodiment achieves the characteristics of high resolution and high pixel, and takes into account the characteristics of day and night confocality and no out-of-focus in the temperature range of -40°C to 85°C, while meeting the large aperture and expanding the scope of use of the product.

[0114] Implementation method five:

[0115] Fig.21 Schematically shows the structure of a glass-plastic hybrid lens according to Embodiment 5 of the present invention.

[0116] In the fifth embodiment, the aperture Fno=1.2, the total length of the lens optical system is 22.2 mm, and the field of view angle is 120°.

[0117] Table 10 below lists the relevant parameters of each lens of this embodiment, including surface type, radius of curvature, thickness, refractive index of the material, and Abbe number:

[0118] Surface number Surface type R-Value thickness Refractive Index Abbe number S0(OBJ) Spherical Infinity Infinity S1 Spherical 38.5415 1.0000 1.62 60.4 S2 Spherical 2.4567 1.7583 S3 Aspheric -2.4561 1.2456 1.53 56.0 S4 Aspheric 2.5478 0.0245 S5 Aspheric 10.5424 2.2453 1.66 20.4 S6 Aspheric -25.3584 0.7532 S7(STO) Spherical Infinity 0.1012 S8 Spherical 14.7864 1.300 1.74 27.8 S9 Spherical 5.2436 2.2145 1.73 54.7 S10 Spherical -3.1546 0.1245 S11 Aspheric 4.5464 3.1245 1.54 55.9 S12 Aspheric -13.1244 0.1457 S13 Aspheric -14.4536 0.7561 1.66 20.4 S14 Aspheric 7.4562 0.3124 S15 Aspheric 7.5461 1.3547 1.52 56.1 S16 Aspheric -17.5461 0.5 S17 Spherical Infinity 0.8 1.52 64.2 S18 Spherical Infinity 3.1547 S19(IMA) Spherical Infinity - - -

[0119] Table 10

[0120] In this embodiment, the aspheric surface data are shown in Table 11 below, where K is the quadratic surface constant of the surface, and A, B, C, D, E, F, and G are the aspheric surface coefficients of the fourth order, sixth order, eighth order, tenth order, twelfth order, fourteenth order, and sixteenth order, respectively:

[0121] Surface number K A B C D E F G S3 -1.01E-01 9.43E-03 -9.58E-04 8.05E-05 -4.37E-06 9.44E-08 0 0 S4 -1.72E+00 6.14E-03 -4.05E-04 -7.32E-07 1.73E-06 -7.87E-08 0 0 S5 -6.88E-01 -8.54E-04 1.78E-04 -1.40E-05 6.74E-07 -1.41E-08 0 0 S6 1.67E-02 -3.50E-04 1.93E-04 -6.25E-06 1.90E-07 -4.03E-09 0 0 S11 -8.86E-02 -1.48E-03 5.63E-05 -1.08E-05 9.15E-08 4.55E-09 0 0 S12 1.29E+01 -1.55E-03 2.59E-05 1.65E-06 -2.75E-07 5.73E-09 0 0 S13 -6.01E+00 -1.47E-04 1.90E-04 -8.43E-06 9.62E-08 6.55E-11 0 0 S14 1.24E-01 -5.20E-03 6.51E-04 -1.43E-05 -1.15E-07 -2.82E-08 0 0 S15 -2.56E-01 -6.23E-03 3.65E-04 7.45E-06 -3.44E-08 -4.44E-08 0 0 S16 -1.56E+00 7.60E-04 -1.63E-04 2.14E-05 -8.82E-07 1.09E-09 0 0

[0122] Table 11

[0123] Figure 22 to Figure 25 The MTF diagram of the glass-plastic hybrid lens according to embodiment 5 of the present invention, the Through-Focus-MTF diagram with a frequency of 240lp / mm, the Through-Focus-MTF diagram with a frequency of 120lp / mm at a high temperature of 80°C, and the Through-Focus-MTF diagram with a frequency of 120lp / mm at a low temperature of -40°C are schematically represented respectively.

[0124] Depend on Figure 22 to Figure 25 It can be seen that the lens of this embodiment achieves the characteristics of high resolution and high pixel, and takes into account the characteristics of day and night confocality and no out-of-focus in the temperature range of -40°C to 85°C, while meeting the large aperture and expanding the scope of use of the product.

[0125] According to the above-mentioned embodiments of the present invention, the lens of the present invention adopts a common setting form of a non-spherical lens made of plastic material and a spherical lens made of glass material, which reduces the production cost of the lens of the present invention. The lens of the present invention can achieve a large aperture, meet the requirements of high-pixel image output, and ensure high resolution at a large aperture. The lens of the present invention optimizes the configuration of the positive and negative focal lengths of each lens to effectively correct the aberration; the overall illumination of the lens of the present invention is uniform and the brightness is high (relative illumination is more than 45%). The lens of the present invention can achieve no defocus in the temperature range of -40℃~85℃, overcoming the difficulty that the plastic aspherical lens is easy to cause focus drift in high and low temperature environments due to its large expansion coefficient. The lens of the present invention can achieve confocal imaging in the range of visible light band to infrared light band. The single component and assembly tolerance of the lens of the present invention are good, and it has good manufacturability. The CRA of the lens of the present invention is ≤15°, and it can be adapted to a variety of sensors, with broad application prospects and improved market competitiveness. The total length of the head of the lens of the present invention is within 25mm and the volume is small.

[0126] The above is only one embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A glass-plastic hybrid lens, comprising 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) and an eighth lens (8) arranged in sequence from the object side to the image side along the optical axis, a total of eight lenses having optical power, characterized in that: The first lens (1), the second lens (2), the fourth lens (4) and the seventh lens (7) are negative power lenses; The third lens (3), the fifth lens (5), the sixth lens (6) and the eighth lens (8) are positive power lenses; The focal length fb of the doublet lens formed by the fourth lens (4) and the fifth lens (5) and the effective focal length f of the glass-plastic hybrid lens satisfy the relationship: 3.6≥fb / f≥1.

5.

2. The glass-plastic hybrid lens according to claim 1, characterized in that: The fourth lens (4) and the fifth lens (5) form a doublet lens with positive refractive power.

3. The glass-plastic hybrid lens according to claim 1 or 2, characterized in that: Along the direction from the object side to the image side, the first lens (1) is a convex-concave lens, the second lens (2) is a lens concave toward the object side, the third lens (3) is a lens with a convex surface on the object side, the fourth lens (4) is a convex-concave lens, the fifth lens (5) is a convex-convex lens, the sixth lens (6) is a convex-convex lens, the seventh lens (7) is a concave-concave lens, and the eighth lens (8) is a convex-convex lens.

4. The glass-plastic hybrid lens according to claim 3, characterized in that: The first lens (1) is a spherical or aspherical lens, the second lens (2) is an aspherical lens, the third lens (3) is an aspherical lens, the fourth lens (4) is a spherical lens, the fifth lens (5) is a spherical lens, the sixth lens (6) is an aspherical lens, the seventh lens (7) is an aspherical lens, and the eighth lens (8) is an aspherical lens.

5. The glass-plastic hybrid lens according to claim 4, characterized in that: All aspherical lenses in the glass-plastic hybrid lens satisfy the relationship: Where z is the axial distance from the surface to the vertex at a height h perpendicular to the optical axis along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the cone coefficient; A4, A6, A8, A 10 , A 12 , A 14 , A 16 ···represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order···aspheric coefficients respectively.

6. The glass-plastic hybrid lens according to claim 1 or 4, characterized in that: At least one of the first lens (1), the fourth lens (4) and the fifth lens (5) has a refractive index Nd≥1.6 and an Abbe number coefficient Vd≥50.

7. The glass-plastic hybrid lens according to claim 1 or 4, characterized in that: The focal length f3 of the third lens (3) and the effective focal length f of the glass-plastic hybrid lens satisfy the relationship: 1.5≤f3 / f≤8.

8. The glass-plastic hybrid lens according to claim 7, characterized in that: The refractive index Nd3 of the third lens (3) is ≥1.6, and the Abbe number coefficient Vd3 is ≤30.

9. The glass-plastic hybrid lens according to claim 1 or 4, characterized in that: The refractive index Nd8 of the eighth lens (8) is ≥1.5, and the Abbe number coefficient Vd8 is ≥50.

10. The glass-plastic hybrid lens according to claim 1 or 4, characterized in that: The focal power of the seventh lens (7) and the focal power of the sixth lens (6) or the eighth lens (8) satisfy the relationship: 2≥|φ7 / φ6|≥1.05 or 2≥|φ7 / φ8|≥1.05; φ7 represents the optical power of the seventh lens (7), φ6 represents the optical power of the sixth lens (6), and φ8 represents the optical power of the eighth lens (8).

11. The glass-plastic hybrid lens according to claim 1, characterized in that: The glass-plastic hybrid lens also includes an aperture (S), which is located between the second lens (2) and the third lens (3), or between the third lens (3) and the fourth lens (4), or between the fifth lens (5) and the sixth lens (6).

12. The glass-plastic hybrid lens according to claim 1, characterized in that: The aperture number Fno of the glass-plastic hybrid lens is ≤1.

2.

13. The glass-plastic hybrid lens according to claim 1, characterized in that: The chief ray deviation angle CRA of the glass-plastic hybrid lens is ≤15°.

14. The glass-plastic hybrid lens according to claim 1, characterized in that: The total length of the optical system of the glass-plastic hybrid lens is ≤25 mm.

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