CN114895432B - Glass-plastic mixed fixed-focus optical system - Google Patents
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- G—PHYSICS
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- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
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Abstract
The invention relates to a glass-plastic mixed fixed-focus optical system, which comprises: a first lens (L1) with negative focal power, a second lens (L2) with positive focal power, a third lens (L3) with positive focal power, a fourth lens (L4) with negative focal power and a fifth lens (L5) with positive focal power which are sequentially arranged along the direction from the object side to the image side, wherein the effective focal length F of the optical system and the optical back focal length BFL of the optical system satisfy the relation: F/BFL is less than or equal to 1.18 and less than or equal to 1.25. The glass-plastic mixed fixed focus optical system provided by the invention has the advantages of low cost, miniaturization, no virtual focus in a high-low temperature state, day-night confocal, large aperture (FNO 1.6), no thermalization and high-quality imaging performance required by 8MP image output.
Description
Technical Field
The invention relates to the technical field of optical elements, systems or instruments, in particular to a glass-plastic mixed fixed-focus optical system.
Background
The security monitoring lens can monitor all weather in multiple directions, and manpower and material resources are greatly saved. The traditional fixed focus lens adopts more full glass design, which is not only unfavorable for miniaturization, but also brings about cost rise. In the current society with high-speed development of science and technology, the requirement on a fixed focus monitoring lens tends to form images with higher definition, miniaturization and clear imaging under the low-illumination condition. Most glass-plastic mixed fixed focus lenses in the market have the advantages that although the cost is greatly reduced, the excellent properties of large aperture, high and low temperature without deficient focus, day and night confocal and the like are difficult to be simultaneously considered under the condition of low cost.
Based on the above-mentioned problems, there is a need to provide an imaging lens which is low in cost, small in size, free from virtual focus at high and low temperatures, large in aperture, and confocal day and night, and has improved imaging performance.
Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide a glass-plastic mixed fixed-focus optical system, which has the advantages of low cost, miniaturization, no virtual focus in a high-low temperature state, day-night confocal, large aperture (FNO 1.6), no thermalization and high-quality imaging performance required by 8MP image output.
In order to achieve the above object, the present invention provides a glass-plastic mixed fixed-focus optical system, comprising: a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with negative focal power and a fifth lens with positive focal power which are sequentially arranged along the direction from an object side to an image side of an optical axis, wherein the effective focal length F of the optical system and the optical back focal length BFL of the optical system meet the relation: F/BFL is less than or equal to 1.18 and less than or equal to 1.25.
According to one aspect of the present invention, the first lens, the second lens, the fourth lens and the fifth lens are all plastic aspherical lenses;
The third lens is a glass spherical lens.
According to one aspect of the invention, the optical axis is oriented in a direction from the object side to the image side,
The first lens is a convex-concave lens;
The second lens is a concave-convex lens;
The third lens and the fifth lens are convex-convex lenses;
The shape of the fourth lens at the paraxial region is concave or convex.
According to one aspect of the invention, the optical system further comprises a stop located between the first lens and the second lens.
According to one aspect of the present invention, a relationship between a focal length F1 of the first lens and a focal length FII of the lens group of the stop on the image plane side is satisfied: -6.53 is less than or equal to F1/FII is less than or equal to-3.8.
According to one aspect of the present invention, a relationship between a distance D2 between a center of the fifth lens image side surface and the stop surface and an optical total length TTL of the optical system is satisfied: D2/TTL is more than or equal to 0.52 and less than or equal to 0.55.
According to one aspect of the present invention, the relation between the sagittal height SAG11 of the maximum optical effective diameter of the first lens object side surface and the curvature radius R1 of the first lens object side surface is satisfied: R1/SAG11 is more than or equal to 1.68 and less than or equal to 1.96.
According to one aspect of the present invention, the relation between the sagittal height SAG12 of the maximum optical effective diameter of the image side surface of the first lens and the curvature radius R2 of the image side surface of the first lens is satisfied: R2/SAG12 is more than or equal to 1.36 and less than or equal to 1.67.
According to one aspect of the present invention, the radius of curvature R3 of the object-side surface of the second lens element and the radius of curvature R2 of the image-side surface of the first lens element satisfy the following relationship: -1.89 < R3/R2 < 1.8.
According to one aspect of the present invention, a relationship between a distance D45 from the fourth lens image side to the fifth lens object side and a distance D34 from the third lens image side to the fourth lens object side is satisfied: D45/(D34+D45) is less than or equal to 0.89 and less than or equal to 0.92.
According to one aspect of the present invention, a relationship between a focal length F3 of the third lens and an effective focal length F of the optical system is satisfied: F3/F is less than or equal to 1.07 and less than or equal to 1.25.
According to one aspect of the present invention, a relationship between a focal length F5 of the fifth lens and an effective focal length F of the optical system is satisfied: F5/F is more than or equal to 0.79 and less than or equal to 0.87.
According to one aspect of the invention, the optical system comprises at least one lens of low dispersion material, and the Abbe number Vd of the lens is greater than or equal to 65.
According to the scheme of the invention, the optical system adopts five lenses in total, and the convexity, the material and the focal power distribution of each lens are reasonably arranged, so that the light transmissibility is improved, various aberrations of the optical system can be well corrected, the optical system is low in cost and small in size (the total length TTL of the optical system containing the protective plate glass is less than or equal to 22.45 mm), simple in structure, free from virtual focus at high and low temperature, day and night confocal, large aperture (FNO 1.6) and athermalization performance are realized, the 8MP image output requirement is met, the overall illumination is uniform, and the brightness is high. Meanwhile, the image plane height of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be suitable for a plurality of sensors.
According to one scheme of the invention, by reasonably matching the spherical lenses and the aspherical lenses, wherein the number of the plastic aspherical lenses is up to four, the powerful aberration correcting capability of the aspherical lenses is fully utilized, and the back focus drift caused by the change of the refractive index of the lenses along with the temperature is greatly eliminated, so that the glass-plastic mixed fixed focus optical system still has good resolution at high and low temperatures, does not have virtual focus in the temperature range of-40 ℃ to 80 ℃ and is confocal day and night.
According to one scheme of the invention, the effective focal length and the optical back focal length of the optical system are set, so that the diversity of the structure assembly process can be realized, the single-part product and the assembly tolerance are good, the manufacturability is good, and the competitiveness of the product is further improved.
According to the scheme of the invention, the relative aperture size of the first lens can be controlled by setting the relation between the curvature radius of the object side surface and the image side surface in the first lens and the sagittal height, so that the incident height of light entering the optical system can be reduced while the processability of the lens is ensured, and the correction of distortion and off-axis aberration is facilitated. In addition, the relationship between the curvature radius of the image side surface of the first lens and the curvature radius of the object side surface of the second lens is favorable for improving the light converging effect, so that the front end structure of the optical system is more compact.
According to the scheme of the invention, by arranging the lens made of the low-dispersion material, chromatic aberration of an optical system can be further corrected, high-quality imaging of blue light and near infrared light is balanced, and the lower risk of purple fringing under the condition of smaller infrared defocusing can be ensured.
Drawings
Fig. 1 schematically shows a schematic structural diagram of a glass-plastic mixed fixed-focus optical system according to a first embodiment of the present invention;
Fig. 2 schematically illustrates a structural schematic diagram of a glass-plastic mixed fixed-focus optical system according to a second embodiment of the present invention;
fig. 3 schematically shows a structural diagram of a glass-plastic hybrid fixed-focus optical system according to a third embodiment of the present invention.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments will be briefly described below. It is apparent that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.
In describing embodiments of the present invention, the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in terms of orientation or positional relationship shown in the drawings for convenience of description and simplicity of description only, and do not denote or imply that the devices or elements in question must have a particular orientation, be constructed and operated in a particular orientation, so that the above terms are not to be construed as limiting the invention.
The present invention will be described in detail below with reference to the drawings and the specific embodiments, which are not described in detail herein, but the embodiments of the present invention are not limited to the following embodiments.
Referring to fig. 1, the glass-plastic mixed fixed-focus optical system of the present invention includes: the first lens L1 with negative focal power, the second lens L2 with positive focal power, the third lens L3 with positive focal power, the fourth lens L4 with negative focal power and the fifth lens L5 with positive focal power are sequentially arranged along the optical axis from the object side to the image side. The optical system further comprises a stop STO located between the first lens L1 and the second lens L2. The effective focal length F of the optical system and the optical back focal length BFL satisfy the relation: F/BFL is less than or equal to 1.18 and less than or equal to 1.25. The first lens L1, the second lens L2, the fourth lens L4 and the fifth lens L5 are all plastic aspheric lenses, and the third lens L3 is a glass spherical lens. The object-side surface of the first lens L1 is convex in shape, and the image-side surface is concave in shape. The object-side surface of the second lens element L2 has a concave shape and the image-side surface has a convex shape. The shapes of the object side surface and the image side surface of the third lens L3 and the fifth lens L5 are convex. The object-side surface of the fourth lens element L4 has a concave or convex shape at the paraxial region, and the image-side surface has a concave shape at the paraxial region. The glass-plastic mixed fixed-focus optical system adopts five lenses, and by reasonably matching spherical lenses and aspherical lenses, the number of the plastic aspherical lenses is up to four, the powerful aberration correcting capability of the aspherical lenses is fully utilized, and the back focus drift caused by the change of the refractive index of the lenses along with the temperature is greatly eliminated, so that the glass-plastic mixed fixed-focus optical system still has good resolution at high and low temperatures, does not have virtual focus in the temperature range of-40 ℃ to 80 ℃ and is confocal day and night. The optical system is favorable for improving the light transmissibility by reasonably setting the convexity and the material and focal power distribution of each lens, can well correct various aberrations of the optical system, and also has the advantages of low cost, miniaturization, simple structure, no virtual focus, day-night confocal, large aperture (FNO 1.6) and no thermal performance at high and low temperatures, and has the advantages of 8MP image output requirement, uniform overall illumination, high brightness, capability improvement and great cost and volume reduction. Meanwhile, the image plane height of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be suitable for a plurality of sensors. By setting the effective focal length and the optical back focal length of the optical system, the diversity of the structure assembly process can be realized, the single-part product and the assembly tolerance are good, the manufacturability is good, and the competitiveness of the product is further improved.
In the present invention, the focal length F1 of the first lens L1 and the focal length FII of the lens group of the stop STO toward the image plane IMA satisfy the relationship: -6.53 is less than or equal to F1/FII is less than or equal to-3.8. The reasonable collocation of the focal power ensures that the glass-plastic mixed fixed-focus optical system has the advantages of large aperture and high resolution.
In the present invention, the sagittal height SAG11 of the maximum optical effective diameter of the object side surface of the first lens L1 and the radius of curvature R1 of the object side surface of the first lens L1 satisfy the relationship: R1/SAG11 is more than or equal to 1.68 and less than or equal to 1.96. The relation between the sagittal height SAG12 of the maximum optical effective diameter of the image-side surface of the first lens L1 and the curvature radius R2 of the image-side surface of the first lens L1 is satisfied: R2/SAG12 is more than or equal to 1.36 and less than or equal to 1.67. By setting the relation between the curvature radius and the sagittal height of the object side surface and the image side surface in the first lens L1, the relative aperture size of the first lens L1 can be controlled, the incident height of light entering the glass-plastic mixed fixed-focus optical system can be reduced while the processability of the lens is ensured, and the correction of distortion and off-axis aberration is facilitated.
In the present invention, the relationship between the radius of curvature R3 of the object-side surface of the second lens element L2 and the radius of curvature R2 of the image-side surface of the first lens element L1 is satisfied: -1.89 < R3/R2 < 1.8. The matching of the relationship between the curvature radius of the image side surface of the first lens L1 and the curvature radius of the object side surface of the second lens L2 is beneficial to improving the light converging effect, so that the front end structure of the glass-plastic mixed fixed-focus optical system is more compact.
In the present invention, the distance D45 from the image side of the fourth lens element L4 to the object side of the fifth lens element L5 and the distance D34 from the image side of the third lens element L3 to the object side of the fourth lens element L4 satisfy the following relationship: D45/(D34+D45) is less than or equal to 0.89 and less than or equal to 0.92. By reasonably controlling the air spacing of the fourth lens L4 to the third lens L3 or the fifth lens L5, it is advantageous to improve the transmissibility, reduce the air spacing sensitivity, and the lens tolerance.
In the present invention, the distance D2 between the center of the image side surface of the fifth lens L5 and the stop STO surface satisfies the relationship between the total optical length TTL of the optical system: D2/TTL is more than or equal to 0.52 and less than or equal to 0.55. The above positional relationship makes the whole glass-plastic mixed fixed focus optical system more compact, and realizes the miniaturization of the volume, so that the total length TTL of the optical system is less than or equal to 22.45mm under the condition of containing the protection flat glass CG.
In the present invention, the focal length F3 of the third lens L3 and the effective focal length F of the optical system satisfy the relation: F3/F is less than or equal to 1.07 and less than or equal to 1.25. The focal length F5 of the fifth lens L5 and the effective focal length F of the optical system satisfy the relation: F5/F is more than or equal to 0.79 and less than or equal to 0.87. Through reasonable collocation of the lens focal power, chromatic aberration of the glass-plastic mixed fixed-focus optical system can be corrected, and resolution of the system is improved.
The optical system at least comprises a lens made of low-dispersion materials, and the Abbe number Vd of the lens is more than or equal to 65. The chromatic aberration of the glass-plastic mixed fixed-focus optical system can be further corrected by the arrangement, high-quality imaging of blue light and near infrared light is balanced, and the lower risk of purple fringing under the condition of smaller infrared defocusing can be ensured.
In summary, referring to fig. 1, the glass-plastic mixed fixed-focus optical system of the invention adopts 5 lenses and a diaphragm STO between the first lens L1 and the second lens L2, and further includes a protection plate glass CG, and the 5 lenses are sequentially 'negative-positive-negative-positive' optical structures from the object side to the image side, and by reasonably setting the convexity and convexity of each lens and the distribution of materials and focal power, the invention is beneficial to improving the light transmissibility, and can well correct various aberrations of the optical system, thereby realizing the large aperture (FNO 1.6) and 8MP image output requirements, and the overall illumination is uniform and the brightness is high. By skillfully matching with glass-plastic mixed materials and positive and negative focal power, the back Jiao Piaoyi of the lens at high and low temperatures is perfectly compensated, the clear imaging of the optical system at the limiting temperature condition is ensured, no virtual focus exists in the temperature range of-40 ℃ to 80 ℃, and day and night confocal exists. The number of the plastic aspherical lenses is up to 4, so that the cost is greatly reduced while the performance of an optical system is improved, and the product competitiveness is improved. Meanwhile, the image plane of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be adapted to a plurality of sensors, has wide application prospect and improves market competitiveness. The total length TTL of the optical system is less than or equal to 22.45mm (including protective plate glass), the volume is small, the single-part product and the assembly tolerance are good, and the manufacturability is good.
The glass-plastic mixed fixed-focus optical system of the invention is specifically described below with reference to the accompanying drawings and tables by using 3 embodiments. In the following embodiments, the present invention refers to the stop STO as one side and the image plane IMA as one side.
The parameters of the various embodiments specifically conforming to the above relationship are shown in table 1 below:
| Conditional expression | Example 1 | Example two | Example III |
| 1.68≤R1/SAG11≤1.96 | 1.8 | 1.96 | 1.9 |
| 1.36≤R2/SAG12≤1.67 | 1.38 | 1.65 | 1.67 |
| -1.89≤R3/R2≤-1.8 | -1.89 | -1.85 | -1.83 |
| -6.53≤F1/FII≤-3.8 | -4.93 | -5 | -6.53 |
| 1.18≤F/BFL≤1.25 | 1.22 | 1.25 | 1.2 |
| 0.89≤D45/(D34+D45)≤0.92 | 0.9 | 0.92 | 0.89 |
| 0.52≤D2/TTL≤0.55 | 0.52 | 0.55 | 0.54 |
| 1.07≤f3/F≤1.25 | 1.25 | 1.22 | 1.18 |
| 0.79≤f5/F≤0.87 | 0.79 | 0.87 | 0.82 |
TABLE 1
In various embodiments of the present invention, the plastic aspherical lens of the glass-plastic hybrid fixed-focus optical system satisfies the following formula:
In the above formula, z is the axial distance from the curved surface to the vertex at the position with the height h perpendicular to the optical axis along the optical axis direction; c represents the curvature at the apex of the aspherical curved surface; k is a conic coefficient; a 4、A6、A8、A10、A12、A14、A16 ··represents fourth order, sixth order, eighth order, tenth order, fourteenth order, sixteen order·aspheric coefficients, respectively.
Example 1
Referring to fig. 1, the parameters of the glass-plastic mixed fixed-focus optical system of the present embodiment are as follows:
TTL＝22.25mm，FNO＝1.6。
The relevant parameters of each lens of the glass-plastic hybrid fixed-focus optical system of the present embodiment, including the surface type, the radius of curvature R value, the thickness, the refractive index of the material, and the abbe number, S1 to S13 represent each surface of each lens, the stop STO, and the protective sheet glass CG in the optical system, as shown in table 2 below.
| Face number | Surface type | R value | Thickness of (L) | Refractive index | Abbe number |
| S1 | Aspherical surface | 3.160 | 1.44 | 1.54 | 55.98 |
| S2 | Aspherical surface | 2.208 | 2.59 | ||
| S3(STO) | Spherical surface | Infinity | 0.75 | ||
| S4 | Aspherical surface | -4.174 | 2.60 | 1.64 | 23.53 |
| S5 | Aspherical surface | -3.784 | 0.07 | ||
| S6 | Spherical surface | 7.133 | 2.85 | 1.44 | 95.10 |
| S7 | Spherical surface | -10.377 | 0.07 | ||
| S8 | Aspherical surface | -2346.908 | 0.8 | 1.64 | 23.53 |
| S9 | Aspherical surface | 3.332 | 0.62 | ||
| S10 | Aspherical surface | 4.737 | 3.8 | 1.54 | 55.71 |
| S11 | Aspherical surface | -8.905 | 5.65 | ||
| S12 | Spherical surface | Infinity | 0.8 | 1.52 | 64.20 |
| S13 | Spherical surface | Infinity | 0.2 | ||
| S14(IMA) | Spherical surface | Infinity |
TABLE 2
The aspherical coefficients of each aspherical lens of the glass-plastic mixed fixed focus optical system of the present embodiment include a quadric constant K value, a fourth order aspherical coefficient a 4, a sixth order aspherical coefficient a 6, an eighth order aspherical coefficient a 8, a tenth order aspherical coefficient a 10, and a twelfth order aspherical coefficient a 12 of the surface, as shown in table 3 below.
TABLE 3 Table 3
Referring to fig. 1, in combination with the above tables 1 to 3, the optical system of this embodiment achieves low cost, miniaturization (the total length of the optical system including the protection plate glass ttl=22.25 mm), simple structure, good resolution at high and low temperatures, no virtual focus in the temperature range of-40 ℃ to 80 ℃, day and night confocal, large aperture (FNO 1.6), no compromise of thermal performance, 8MP image output requirement, uniform overall illuminance, and high brightness. Meanwhile, the image plane height of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be suitable for a plurality of sensors. The single-part product has good assembly tolerance and good manufacturability.
Example two
Referring to fig. 2, in this embodiment, parameters of the glass-plastic hybrid fixed-focus optical system are as follows:
TTL＝21.56mm，FNO＝1.7。
The relevant parameters of each lens of the glass-plastic mixed fixed-focus optical system of the present embodiment, including the surface type, the radius of curvature R value, the thickness, the refractive index of the material, and the abbe number, S1 to S13 represent each surface of each lens, the stop STO, and the protection sheet glass CG in the fixed-focus lens, as shown in table 4 below.
TABLE 4 Table 4
The aspherical coefficients of each aspherical lens of the glass-plastic mixed fixed focus optical system of the present embodiment include the quadric constant K value, the fourth order aspherical coefficient a 4, the sixth order aspherical coefficient a 6, the eighth order aspherical coefficient a 8, the tenth order aspherical coefficient a 10 and the twelve order aspherical coefficient a 12 of the surface, as shown in table 5 below.
| Face number | K | A4 | A6 | A8 | A10 | A12 |
| S1 | -1.3851E+00 | 2.979E-003 | -1.468E-004 | -4.761E-006 | -7.264E-007 | -4.761E-008 |
| S2 | -0.4395E+00 | -3.759E-003 | -8.852E-004 | -1.988E-005 | -2.466E-005 | 1.109E-006 |
| S4 | -0.3315E+00 | 9.974E-004 | -3.927E-004 | 8.729E-007 | -7.172E-006 | -6.821E-008 |
| S5 | -2.9033E+00 | -2.237E-003 | -4.316E-005 | -3.320E-006 | -5.202E-007 | 4.463E-008 |
| S8 | -2.5984E+02 | -8.088E-004 | -1.485E-004 | -1.964E-005 | -6.146E-004 | -5.794E-007 |
| S9 | -5.3858E+00 | -7.013E-004 | -1.210E-004 | 2.739E-006 | 1.008E-006 | 1.263E-008 |
| S10 | -6.7666E+00 | -9.463E-005 | 7.479E-005 | -2.899E-006 | 1.463E-006 | -2.361E-007 |
| S11 | -59.187E+01 | -3.961E-003 | 4.838E-004 | -3.217E-005 | -2.165E-007 | 4.125E-007 |
TABLE 5
Referring to fig. 2, in combination with the above tables 1 and 4 to 5, the optical system of this embodiment achieves low cost, miniaturization (the total length of the optical system including the protection plate glass ttl=21.56 mm), simple structure, good resolution at high and low temperatures, no virtual focus in the temperature range of-40 to 80 ℃, day and night confocal, large aperture (FNO 1.7), no thermal performance, 8MP image output requirement, uniform overall illuminance, and high brightness. Meanwhile, the image plane height of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be suitable for a plurality of sensors. The single-part product has good assembly tolerance and good manufacturability.
Example III
Referring to fig. 3, in this embodiment, parameters of the glass-plastic hybrid fixed-focus optical system are as follows:
TTL＝21.97mm，FNO＝1.8。
The relevant parameters of each lens of the glass-plastic mixed fixed-focus optical system of the present embodiment, including the surface type, the radius of curvature R value, the thickness, the refractive index of the material, and the abbe number, S1 to S13 represent each surface of each lens, the stop STO, and the protection sheet glass CG in the fixed-focus lens, as shown in table 6 below.
TABLE 6
The aspherical coefficients of each aspherical lens of the glass-plastic mixed fixed focus optical system of this embodiment include the quadric constant K value, the fourth order aspherical coefficient a 4, the sixth order aspherical coefficient a 6, the eighth order aspherical coefficient a 8, the tenth order aspherical coefficient a 10 and the twelve order aspherical coefficient a 12 of the surface, as shown in table 7 below.
| Face number | K | A4 | A6 | A8 | A10 | A12 |
| S1 | -1.3481E+00 | 2.596E-003 | -1.391E-004 | -7.271E-006 | 7.525E-007 | -2.539E-007 |
| S2 | -0.4483E+00 | -4.446E-003 | -9.916E-004 | 2.861E-006 | -2.047E-005 | -3.622E-007 |
| S4 | -0.4408E+00 | 1.156E-003 | -5.675E-004 | 2.383E-005 | -7.718E-006 | -6.783E-007 |
| S5 | -3.1453E+00 | -2.315E-003 | -9.925E-005 | -3.348E-006 | 3.662E-008 | -5.341E-008 |
| S8 | -8.2395E+01 | -2.584E-003 | -1.685E-004 | -6.312E-006 | 3.668E-006 | -4.045E-007 |
| S9 | -5.3053E+00 | -1.735E-003 | -2.627E-004 | 3.799E-005 | -2.878E-006 | -1.050E-008 |
| S10 | -5.5367E+00 | -1.939E-003 | 2.528E-004 | -2.014E-005 | 1.173E-006 | -5.723E-008 |
| S11 | -27.063E+01 | -3.898E-003 | 2.392E-004 | 1.175E-005 | -4.728E-006 | 5.854E-007 |
TABLE 7
Referring to fig. 3, in combination with the above tables 1,6 to 7, the optical system of this embodiment achieves low cost, miniaturization (the total length of the optical system including the protection plate glass ttl=21.97 mm), simple structure, good resolution at high and low temperatures, no virtual focus in the temperature range of-40 to 80 ℃, day and night confocal, large aperture (FNO 1.8), no thermal performance, 8MP image output requirement, uniform overall illuminance, and high brightness. Meanwhile, the image plane height of the optical system can reach phi 7.0mm, CRA is less than or equal to 12 degrees, and the optical system can be suitable for a plurality of sensors. The single-part product has good assembly tolerance and good manufacturability.
The above description is only one embodiment of the present invention and is not intended to limit the present invention, and various modifications and variations of the present invention will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A glass-plastic hybrid fixed-focus optical system, comprising: a first lens (L1) having negative optical power, a second lens (L2) having positive optical power, a third lens (L3) having positive optical power, a fourth lens (L4) having negative optical power, and a fifth lens (L5) having positive optical power, which are sequentially arranged in a direction from an object side to an image side along an optical axis, characterized in that an effective focal length F of the optical system and an optical back focal length BFL of the optical system satisfy a relationship: F/BFL is less than or equal to 1.18 and less than or equal to 1.25;
the sagittal height SAG11 of the maximum optical effective diameter of the object side surface of the first lens (L1) and the curvature radius R1 of the object side surface of the first lens (L1) satisfy the relationship: R1/SAG11 is more than or equal to 1.68 and less than or equal to 1.96;
the sagittal height SAG12 of the maximum optical effective diameter of the image side surface of the first lens (L1) and the curvature radius R2 of the image side surface of the first lens (L1) satisfy the relation: R2/SAG12 is more than or equal to 1.36 and less than or equal to 1.67;
The center distance D45 from the image-side surface of the fourth lens element (L4) to the object-side surface of the fifth lens element (L5) and the center distance D34 from the image-side surface of the third lens element (L3) to the object-side surface of the fourth lens element (L4) satisfy the following relationship: D45/(D34+D45) is less than or equal to 0.89 and less than or equal to 0.92.
2. The glass-plastic mixed fixed focus optical system according to claim 1, wherein the first lens (L1), the second lens (L2), the fourth lens (L4) and the fifth lens (L5) are all plastic aspherical lenses;
the third lens (L3) is a glass spherical lens.
3. The glass-plastic hybrid fixed focus optical system according to claim 1, wherein in a direction from an object side to an image side along an optical axis,
The first lens (L1) is a convex-concave lens;
the second lens (L2) is a concave-convex lens;
The third lens (L3) and the fifth lens (L5) are convex-convex lenses;
the shape of the fourth lens (L4) at the paraxial region is concave or convex.
4. The glass-plastic hybrid fixed focus optical system according to claim 1, characterized in that it further comprises a Stop (STO) located between the first lens (L1) and the second lens (L2).
5. The glass-plastic mixed fixed focus optical system according to claim 4, wherein a relation between a focal length F1 of the first lens (L1) and a focal length FII of the lens group of the Stop (STO) toward the image plane (IMA) side is satisfied: -6.53 is less than or equal to F1/FII is less than or equal to-3.8.
6. The glass-plastic hybrid fixed focus optical system according to claim 4, wherein a relationship between a distance D2 of a center of an image side surface of the fifth lens (L5) from the Stop (STO) surface and an optical total length TTL of the optical system is satisfied: D2/TTL is more than or equal to 0.52 and less than or equal to 0.55.
7. The glass-plastic hybrid fixed focus optical system according to any one of claims 1 to 6, wherein a relation between a radius of curvature R3 of an object side surface of the second lens element (L2) and a radius of curvature R2 of an image side surface of the first lens element (L1) is satisfied: -1.89 < R3/R2 < 1.8.
8. The glass-plastic hybrid fixed focus optical system according to any one of claims 1 to 6, characterized in that the relation between the focal length F3 of the third lens (L3) and the effective focal length F of the optical system is satisfied: F3/F is less than or equal to 1.07 and less than or equal to 1.25.
9. The glass-plastic hybrid fixed focus optical system according to any one of claims 1 to 6, wherein a relation between a focal length F5 of the fifth lens (L5) and an effective focal length F of the optical system is satisfied: F5/F is more than or equal to 0.79 and less than or equal to 0.87.
10. The glass-plastic mixed fixed focus optical system according to any one of claims 1 to 6, wherein the optical system comprises at least one lens of low dispersion material, and the abbe number Vd of the lens is not less than 65.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20180087133A (en) * | 2017-01-22 | 2018-08-01 | 둥관 위퉁 옵티컬 테크놀로지 컴퍼니 리미티드 | Small-sized low-cost 4mp non-thermal fixed-focus lens |
| CN110441890A (en) * | 2019-09-16 | 2019-11-12 | 舜宇光学(中山)有限公司 | Glass modeling mixing wide-angle lens |
| CN112859299A (en) * | 2021-03-19 | 2021-05-28 | 舜宇光学(中山)有限公司 | Fixed focus lens |
| CN215833684U (en) * | 2021-05-17 | 2022-02-15 | 上海峰梅光学科技有限公司 | Optical lens |
| CN114236788A (en) * | 2021-12-14 | 2022-03-25 | 东莞市长益光电有限公司 | 6mm large-aperture athermalization glass-plastic hybrid lens |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| EP3605180B1 (en) * | 2017-04-26 | 2021-11-17 | Kyocera Corporation | Imaging lens |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20180087133A (en) * | 2017-01-22 | 2018-08-01 | 둥관 위퉁 옵티컬 테크놀로지 컴퍼니 리미티드 | Small-sized low-cost 4mp non-thermal fixed-focus lens |
| CN110441890A (en) * | 2019-09-16 | 2019-11-12 | 舜宇光学(中山)有限公司 | Glass modeling mixing wide-angle lens |
| CN112859299A (en) * | 2021-03-19 | 2021-05-28 | 舜宇光学(中山)有限公司 | Fixed focus lens |
| CN215833684U (en) * | 2021-05-17 | 2022-02-15 | 上海峰梅光学科技有限公司 | Optical lens |
| CN114236788A (en) * | 2021-12-14 | 2022-03-25 | 东莞市长益光电有限公司 | 6mm large-aperture athermalization glass-plastic hybrid lens |
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