Infrared bi-pass periscopic telephoto lens
The infrared dual-pass periscope telephoto lens design uses an all-plastic lens and aspherical structure to solve the problems of large size and high cost of traditional periscope telephoto lenses, achieving the effect of lightweight and high imaging quality.
Patent Information
- Application Number
- CN202511036543.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-27
- Publication Date
- 2025-09-26
AI Technical Summary
Traditional periscope telephoto lenses are large in size, high in cost, and have poor imaging quality. In addition, the refractive index difference between infrared and visible light materials is large, making it difficult to simultaneously correct chromatic aberration and field area, and cannot meet the development trend of light, thin and short electronic products.
It adopts an infrared dual-pass periscope telephoto lens design, including the first lens, second lens, third lens, fourth lens and aperture. The lens is made of all-plastic molding, combined with aspheric design and optimized optical parameters to achieve a four-lens structure, optimize optical performance, and reduce weight and cost.
It achieves lightweight, low-cost and high-quality imaging, which is in line with the development trend of thin and light electronic products. The lens is made of all-plastic molding, which reduces the weight and is cheaper than glass lenses, optimizing the imaging effect.
Smart Images
Figure CN120703942A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of camera lenses, and in particular to an infrared dual-pass periscope telephoto lens. Background Art
[0002] The periscope telephoto lens is a special optical design, mainly used to enhance the zoom capability of electronic mobile devices, greatly improving the user's photography experience. Among them, the general periscope telephoto lens adopts a design of 5P or above, and the dual-pass periscope telephoto lens is designed with a lens of 6P or above.
[0003] Although traditional periscope telephoto lenses enhance the user's photography experience, they also have the disadvantages of being large and expensive. In addition, the large difference in refractive index between infrared and visible light materials makes it difficult to simultaneously correct aberrations under the lens, especially chromatic aberration and field of view. Not only can this fail to ensure the requirements of high image quality and low distortion, but it also does not meet the development trend of today's electronic products, which are characterized by high functionality and a thin and light appearance. Summary of the Invention
[0004] The purpose of the present invention is to solve the problems of traditional periscope telephoto lenses, such as large size, high cost and poor imaging quality, and to propose an infrared dual-pass periscope telephoto lens.
[0005] In order to achieve the above object, the present invention adopts the following technical solutions: An infrared dual-pass periscope telephoto lens comprises a first lens, a second lens, a third lens, and a fourth lens, wherein the object-side surfaces and image-side surfaces of the first lens, the second lens, the third lens, and the fourth lens are all aspherical surfaces, and the lens further comprises an aperture provided in front of the first lens. The first lens has positive refractive power, and the second lens, the third lens, and the fourth lens all have negative refractive power. The object-side surface of the first lens is convex at the paraxial position, the object-side surface of the second lens is convex, the image-side surface of the third lens is concave, and the image-side surface of the fourth lens is convex. 1.024<TTL / f<1.025, and 0.446<SAG32 / CT3<0.448.
[0006] As a preferred embodiment of the present invention, 0.518 <L1 / L2<0.519。
[0007] As a preferred embodiment of the present invention, -0.189 <ImgH / f3<-0.189。
[0008] As a preferred embodiment of the present invention, 1.414 <CT1 / CT2≤1.418。
[0009] As a preferred embodiment of the present invention, 0.166 <Yc31 / f<0.167。
[0010] As a preferred embodiment of the present invention, 0.496 <T23 / AAT<0.588。
[0011] As a preferred embodiment of the present invention, -1.920 <efl / f4<-1.861。
[0012] As a preferred embodiment of the present invention, -0.348 <f / f34<-0.341。
[0013] As a preferred embodiment of the present invention, 3.603 <ca11 / sd36<3.61。
[0014] Compared with the prior art, the present invention provides an infrared dual-pass periscope telephoto lens with the following beneficial effects: 1. This infrared dual-pass periscope telephoto lens adopts a four-lens design consisting of a first lens, a second lens, a third lens, a fourth lens, and an aperture. The surface structure of each lens is combined with the optimized range of optical parameters. A high infrared transmittance plastic combination is used to achieve dual-band transmittance. The lenses are molded entirely of plastic to reduce the overall weight, which meets the current requirements of light-weight cameras for electronic products. In addition, the price of plastic lenses is lower than that of glass lenses, which can also reduce production costs. This is in line with the current development trend of electronic products with excellent functions and light, thin and short appearance.
[0015] The parts not involved in the device are the same as those in the prior art or can be implemented using the prior art. The present invention solves the problems of traditional periscope telephoto lenses, such as large size, high cost and poor imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a schematic diagram of the planar structure of an infrared dual-pass periscope telephoto lens proposed in the present invention; Figure 2 Distortion of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 1 ; Figure 3 Axial chromatic aberration curve of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 1 ; Figure 4 Distortion of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 2 ; Figure 5 Axial chromatic aberration curve of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 2 ; Figure 6 Distortion of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 3 ; Figure 7Axial chromatic aberration curve of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 3 ; Figure 8 Distortion of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 4 ; Figure 9 Axial chromatic aberration curve of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 4 ; Figure 10 Distortion of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 5 ; Figure 11 Axial chromatic aberration curve of an infrared dual-pass periscope telephoto lens proposed by the present invention Figure 5 .
[0017] In the figure: 1, first lens; 2, second lens; 3, third lens; 4, fourth lens; 5, aperture. DETAILED DESCRIPTION
[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.
[0019] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.
[0020] Example 1: Reference Figure 1An embodiment of the present invention provides an infrared dual-pass periscope telephoto lens, comprising a first lens 1, a second lens 2, a third lens 3, and a fourth lens 4. The object-side surface and the image-side surface of the first lens 1, the second lens 2, the third lens 3, and the fourth lens 4 are all aspherical surfaces. The first lens 1, the second lens 2, the third lens 3, and the fourth lens 4 are made of plastic. The lens 1, the second lens 2, the third lens 3, and the fourth lens 4 also include an aperture 5 disposed in front of the first lens 1. The aperture 5 is used to control the amount of light passing through the lens. The first lens 1 has positive refractive power, and the second lens 2, the third lens 3, and the fourth lens 4 all have negative refractive power. The positive and negative refractive powers cause the incident light to diffuse outward, expand the field of view, reduce distortion, and thereby optimize the optical performance of the entire system. The object-side surface of the first lens 1 is convex at the paraxial position, the object-side surface of the second lens 2 is convex, the image-side surface of the third lens 3 is concave, and the image-side surface of the fourth lens 4 is convex. In some embodiments, the ratio of the distance from the object-side surface of the first lens 1 to the imaging plane on the optical axis to the focal length of the entire optical imaging system satisfies the following range: 1.024<TTL / f<1.025; The ratio of the horizontal displacement distance between the intersection of the image side surface of the third lens 3 and the optical axis to the maximum effective radius position of the image side surface of the third lens 3 and the optical axis to the focal length of the entire optical imaging system satisfies the following range: 0.446<SAG32 / CT3<0.448.
[0021] Through the above ratio, the optimal parameter range of the lens can be obtained.
[0022] Specifically, during use, a four-lens design consisting of a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, and an aperture 5 is adopted, and the surface structure of each lens is combined with the optimized range of optical parameters. A high infrared transmittance plastic combination is used to achieve dual-band transmittance. The lenses are molded entirely of plastic to reduce the overall weight, which meets the current requirements of light-weight cameras for electronic products. In addition, the price of plastic lenses is lower than that of glass lenses, which can also reduce production costs, which is in line with the current development trend of electronic products with excellent functions and light, thin and short appearance.
[0023] In some embodiments, the ratio of the distance from the aperture 5 to the image side surface of the second lens 2 on the optical axis to the distance from the aperture 5 to the image side surface of the third lens 3 on the optical axis meets the following range: 0.518 <L1 / L2<0.519。
[0024] In some embodiments, the ratio of the maximum imaging height of the optical imaging system to the effective focal length of the third lens 3 is within the following range: -0.189 <ImgH / f3<-0.189。
[0025] In some embodiments, the ratio of the thickness of the first lens 1 on the optical axis to the thickness of the second lens 2 on the optical axis meets the following range: 1.414 <CT1 / CT2≤1.418。
[0026] In some embodiments, the ratio of the vertical distance from the inflection point on the object-side surface of the third lens 3 that is closest to the imaging plane to the optical axis to the focal length of the entire optical imaging system is within the following range: 0.166 <Yc31 / f<0.167。
[0027] In some embodiments, the ratio of the air gap on the optical axis from the image side surface of the second lens 2 to the object side surface of the third lens 3 to the sum of the air gaps between adjacent lenses from the first lens 1 to the third lens 3 is within the following range: 0.496 <T23 / AAT<0.588。
[0028] In some embodiments, the ratio of the effective focal length of the lens to the effective focal length of the fourth lens 4 is within the following range: -1.920 <efl / f4<-1.861。
[0029] In some embodiments, the ratio of the focal length of the entire optical imaging system to the focal length of the combination of the third lens 3 and the fourth lens 4 is within the following range: -0.348 <f / f34<-0.341。
[0030] In some embodiments, the ratio of the maximum effective diameter of the object surface of the first lens 1 to the maximum effective radius of the image side surface of the third lens 3 is within the following range: 3.603 <ca11 / sd36<3.61。
[0031] Through the above ratio, the optimal parameter range of the lens can be obtained.
[0032] The meanings of “alphanumeric values” in this invention are as follows: TTL: The distance from the object side of the first lens to the imaging surface on the optical axis; f: focal length of the entire optical imaging system; SAG32: The horizontal displacement between the intersection of the image side surface of the third lens 3 and the optical axis and the maximum effective radius of the image side surface of the third lens 3 and the optical axis; CT3: thickness of the third lens 3 on the optical axis; L1: distance from the aperture 5 to the image side of the second lens 2 on the optical axis; L2: distance from the aperture 5 to the image side of the third lens 3 on the optical axis; ImgH: maximum imaging height of the optical imaging system; CT1: thickness of the first lens 1 on the optical axis; CT2: thickness of the second lens 2 on the optical axis; Yc31: The vertical distance from the inflection point on the object side of the third lens 3 that is closest to the image plane to the optical axis; T23: The air gap on the optical axis between the image side of the second lens element 2 and the object side of the third lens element 3; AAT: the sum of the air gaps between adjacent lenses from the first lens 1 to the third lens 3; efl: effective focal length of the lens; f4: effective focal length of the fourth lens 4; f3: effective focal length of the third lens 3; f34: the focal length of the third lens 3 and the fourth lens 4 combined; Ca11: the maximum effective diameter of the object surface of the first lens 1; Sd36: the maximum effective radius of the image-side surface of the third lens 3 .
[0033] Example 2: Based on Example 1, the specific parameters selected are f=27.8mm, Fno=2.59, FOV=12.42° and aspheric coefficient to obtain the following table:
[0034]
[0035] Specifically, through the data in the above table, it is possible to generate Figure 2 and Figure 3 .
[0036] Example 3: Based on Example 1, the specific parameters selected are f=28.1mm, Fno=2.62, FOV=12.28° and aspheric coefficient to obtain the following table:
[0037]
[0038] Specifically, through the data in the above table, it is possible to generate Figure 4 and Figure 5 .
[0039] Example 4: Based on Example 1, the specific parameters selected are f=28.07mm, Fno=2.61, FOV=12.30° and aspheric coefficient to obtain the following table:
[0040]
[0041] Specifically, through the data in the above table, it is possible to generate Figure 6 and Figure 7 .
[0042] Embodiment 5: Based on Example 1, the specific parameters selected are f=28.04mm, Fno=2.61, FOV=12.31° and aspheric coefficient to obtain the following table:
[0043]
[0044] Specifically, through the data in the above table, it is possible to generate Figure 8 and Figure 9 .
[0045] Example 6: Based on Example 1, the specific parameters selected are f=27.80mm, Fno=2.59, FOV=12.42° and aspheric coefficient to obtain the following table:
[0046]
[0047] Specifically, through the data in the above table, it is possible to generate Figure 10 and Figure 11 .
[0048] In the above table: f represents focal length, Fno represents aperture number, and FOV represents field of view angle. These three parameters work together in the design of an infrared dual-pass periscope telephoto lens to ensure high imaging quality and low distortion of the lens, thereby stably and accurately identifying biometric features.
[0049] The present invention Figure 2 、 Figure 4 、 Figure 6 、 Figure 8 、 Figure 10 The comparison of the changes in the distortion curves shows that: the performance of the lens at different focal lengths, the size of the deformation of the object after imaging through the lens, the closer the distortion curve is to 0, the closer the image shape is to the shape of the object; And, through Figure 3 、 Figure 5 、 Figure 7 、 Figure 9 、 Figure 11Comparing the changes in the central axial chromatic aberration curves shows that each curve represents the focal position of light of different wavelengths after passing through the lens. The closer the different curves are, the better the chromatic aberration effect of the lens.
[0050] This infrared dual-pass periscope telephoto lens adopts a four-lens design consisting of a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, and an aperture 5. The surface structure of each lens is combined with the optimized range of optical parameters. A high infrared transmittance plastic combination is used to achieve dual-band transmittance. The lenses are molded entirely of plastic to reduce the overall weight, which meets the current demand for lightweight cameras in electronic products. In addition, the price of plastic lenses is lower than that of glass lenses, which can also reduce production costs. This is in line with the current development trend of electronic products that have high functionality and a thin and compact appearance.
[0051] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.
Claims
1. An infrared dual-pass periscope telephoto lens, comprising a first lens (1), a second lens (2), a third lens (3) and a fourth lens (4), characterized in that: The object side surface and image side surface of the first lens (1), the second lens (2), the third lens (3) and the fourth lens (4) are all aspherical surfaces, and further include a stop (5) arranged in front of the first lens (1). The first lens (1) has positive refractive power, the second lens (2), the third lens (3) and the fourth lens (4) all have negative refractive power, the object side surface of the first lens (1) is convex at the paraxial position, the object side surface of the second lens (2) is convex, the image side surface of the third lens (3) is concave, and the image side surface of the fourth lens (4) is convex, 1.024<TTL / f<1.025, 0.446<SAG32 / CT3<0.
448.
2. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: 0.518 <L1 / L2<0.519。 3. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: -0.189 <ImgH / f3<-0.189。 4. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: 1.414 <CT1 / CT2≤1.418。 5. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: 0.166 <Yc31 / f<0.167。 6. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: 0.496 <T23 / AAT<0.588。 7. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: -1.920 <efl / f4<-1.861。 8. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: -0.348 <f / f34<-0.341。 9. The infrared dual-pass periscope telephoto lens according to claim 1, characterized in that: 3.603 <ca11 / sd36<3.61。