Large aperture optical system and camera module using the same
Patent Information
- Application Number
- CN202522067216.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-25
- Publication Date
- 2026-09-25
- Estimated Expiration
- 2035-09-25
AI Technical Summary
[0003]为克服现有光学镜头存在像素较低、视场角较小、日夜效果差、进光量小的技术问题，本申请提供了一种大光圈光学系统，通过对各个透镜进行面型以及光焦度的合理分配，优化镜头像差，具备优秀的解析力、高像素、大光圈、无热化、日夜共焦、重量轻等特点，在IPC市场中具有更大的竞争力
本实用新型提供一种大光圈光学系统及其应用的摄像模组，主要由6枚透镜构成，镜片枚数合理，结构简单，通过合理分配镜片光焦度，优化镜头像差，提升光学系统的成像质量，兼顾超广角、高照度、日夜共焦、温度特性优异的特性，在IPC市场上具有巨大的潜能。
Smart Images
Figure CN224803290U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of optical imaging, and more particularly to a large aperture optical system and a camera module for its application. Background Technology
[0002] With the advancement of science and technology and the development of society and the economy, camera lenses are widely used in various fields, especially in the field of security monitoring. However, previous camera lenses or optical systems have shortcomings such as low pixel count, small field of view, poor day and night performance, and low light intake, which make it difficult to meet the needs of users. Utility Model Content
[0003] To overcome the technical problems of existing optical lenses, such as low pixel count, small field of view, poor day and night performance, and low light intake, this application provides a large aperture optical system. By rationally allocating the surface shape and optical power of each lens, the lens aberration is optimized, resulting in excellent resolution, high pixel count, large aperture, no pyrolysis, day and night cofocus, and light weight, making it more competitive in the IPC market.
[0004] An optical system comprising, sequentially from the object plane to the image plane along the optical axis, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens: The object side of the first lens is convex, and the image side is concave; its optical power is negative. The object side of the second lens is concave, and the image side is convex; its optical power is positive. The third lens has convex surfaces on both the object plane and the image plane, and its optical power is positive. The fourth lens has concave surfaces on both the object plane and the image plane, and its optical power is negative. The fifth lens has convex surfaces on both the object plane and image plane sides, and its optical power is positive.
[0005] Preferably, each lens of the optical system satisfies the following conditions: -13.5mm < f1 < -3.2mm; 50mm < f2 < 200mm; 4.5mm < f3 < 8.2mm; -6.5mm < f4 < -3.5mm; 3.1mm < f5 < 7.5mm; Where f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f5 is the focal length of the fifth lens.
[0006] Preferably, each lens of the optical system satisfies the following conditions: Nd1 > 1.7, Vd1 < 56; Nd2 > 1.6, Vd2 < 30; Nd3 > 1.51, Vd3 < 75; Nd4 > 1.6, Vd4 < 30; Nd5 > 1.51, Vd5 < 60; Wherein, Nd1 is the refractive index of the first lens, and Vd1 is the Abbe number of the first lens; Nd2 is the refractive index of the second lens, and Vd2 is the Abbe number of the second lens; Nd3 is the refractive index of the third lens, and Vd3 is the Abbe number of the third lens; Nd4 is the refractive index of the fourth lens, and Vd4 is the Abbe number of the fourth lens; Nd5 is the refractive index of the fifth lens, and Vd5 is the Abbe number of the fifth lens.
[0007] Preferably, the relative illuminance of the maximum field of view of the optical system satisfies: RI ≥ 30%.
[0008] Preferably, the radius of curvature R1 of the object surface side of the first lens satisfies: R1 ≤ 30mm.
[0009] Preferably, the total optical length (TTL) and aperture (FNO) of the optical system satisfy: TTL ≤ 23 mm, FNO ≤ 1.7.
[0010] Preferably, the third lens is a glass lens.
[0011] Preferably, the horizontal field angle (FOV) of the optical system satisfies: FOV≥145°, and the maximum image circle satisfies: MIC≥6.9mm.
[0012] Preferably, the aperture is positioned between the second lens and the third lens.
[0013] Preferably, the fourth lens and the fifth lens are bonded together to form a combined lens.
[0014] On the other hand, embodiments of this application also provide a camera module, which includes at least an optical lens, and the optical lens is equipped with the above-mentioned lens optical system.
[0015] Compared with the prior art, the beneficial effects of this application are as follows: This utility model provides a large aperture optical system and its application in a camera module, which is mainly composed of 6 lenses. The number of lenses is reasonable and the structure is simple. By rationally allocating the optical power of the lenses, the lens aberration is optimized and the imaging quality of the optical system is improved. It also takes into account the characteristics of ultra-wide angle, high illumination, day and night confocality, and excellent temperature characteristics, and has great potential in the IPC market. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below.
[0017] Figure 1 This is a schematic diagram of the structure of the optical system or camera module in Embodiment 1 of this application; Figure 2 This is a graph showing the astigmatism and distortion of the optical system or camera module in Embodiment 1 of this application; Figure 3 This is the MTF curve of the optical system or camera module of Embodiment 1 of this application; Figure 4 This is a schematic diagram of the structure of the optical system or camera module in Embodiment 2 of this application; Figure 5 This is a graph showing the astigmatism and distortion of the optical system or camera module in Embodiment 2 of this application; Figure 6 This is the MTF curve of the optical system or camera module in Embodiment 2 of this application; Figure 7 This is a schematic diagram of the structure of the optical system or camera module in Embodiment 3 of this application; Figure 8 This is a graph showing the astigmatism and distortion of the optical system or camera module in Embodiment 3 of this application; Figure 9 This is the MTF curve of the optical system or camera module in Embodiment 3 of this application. Detailed Implementation
[0018] like Figure 1-9 As shown, this application provides a large aperture optical system, which consists of a first lens 1, a second lens 2, an aperture stop STO, a third lens 3, a fourth lens 4, a fifth lens 5, and an infrared filter 6 in sequence along the optical axis from the object plane to the image plane.
[0019] The object plane side S1 of the first lens 1 is convex, and the image plane side S2 is concave, and its optical power is negative. The object plane side S3 of the second lens 2 is concave, and the image plane side S4 is convex, and its optical power is positive. The object plane S5 and image plane S6 of the third lens 3 are both convex surfaces, and its optical power is positive. The fourth lens 4 has concave surfaces on both the object plane side S7 and the image plane side S8, and its optical power is negative. The fifth lens 5 has convex surfaces on both the object plane side S8 and the image plane side S9, and its optical power is positive. This invention provides a large-aperture optical system and its application in a camera module, mainly composed of five lenses. The first lens has a convex object side and a concave image side, with negative optical power. The second lens has a concave object side and a convex image side, with positive optical power. The third lens has convex object and image sides, with positive optical power. The fourth lens has concave object and image sides, with negative optical power. The fifth lens has convex object and image sides, with positive optical power. The number of lenses is reasonable, the structure is simple, and by rationally allocating the optical power of the lenses, lens aberrations are optimized, improving the imaging quality of the optical system. It also takes into account the characteristics of ultra-wide-angle, high illumination, day and night confocality, and excellent temperature characteristics, and has great potential in the IPC market.
[0020] Furthermore, as a preferred embodiment of this utility model and not a limitation thereof, each lens of the optical system satisfies the following conditions, wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f5 is the focal length of the fifth lens: -13.5 mm < f1 < -3.2 mm. This design allows the first lens 1 to have a large negative optical power, which is beneficial to reducing astigmatism and field curvature of the optical system. With 50mm < f2 < 200mm, by constraining the ratio of the optical power of the second lens 2 to the effective focal length of the optical imaging system within a reasonable range, the spherical aberration of the system can be finely adjusted and controlled, thereby effectively improving the imaging quality of the system. With 4.5mm < f3 < 8.2mm, by constraining the ratio of the optical power of the third lens 3 to the effective focal length of the optical imaging system within a reasonable range, the optical system has the advantages of ultra-wide angle, large aperture, small size, and excellent temperature characteristics. -6.5mm < f4 < 3.5mm. By constraining the ratio of the optical power of the fourth lens 4 to the effective focal length of the optical imaging system within a reasonable range, the spherical aberration of the system can be finely adjusted and controlled, thereby effectively improving the imaging quality of the system. With 3.1mm < f5 < 7.5mm, by constraining the ratio of the optical power of the fifth lens 5 to the effective focal length of the optical imaging system within a reasonable range, the optical system has the advantages of ultra-wide angle, large aperture, small size, and excellent temperature characteristics. Furthermore, the refractive index Nd1 and Abbe number Vd1 of the first lens 1 satisfy: Nd1 > 1.7, Vd1 < 56. This design can effectively reduce chromatic aberration, optimize lens aberration, and thus effectively improve the imaging quality of the system. Furthermore, the refractive index Nd2 and Abbe number Vd2 of the second lens 2 satisfy: Nd2 > 1.6, Vd2 < 20. This design can effectively reduce chromatic aberration, optimize lens aberration, and thus effectively improve the imaging quality of the system. Furthermore, the refractive index Nd3 and Abbe number Vd3 of the third lens 3 satisfy: Nd3 > 1.51, Vd3 < 75. This design can effectively reduce chromatic aberration, optimize lens aberration, and thus effectively improve the imaging quality of the system. Furthermore, the refractive index Nd4 and Abbe number Vd4 of the fourth lens 4 satisfy: Nd4 < 1.6, Vd4 < 30. This design can effectively reduce chromatic aberration, optimize lens aberration, and thus effectively improve the imaging quality of the system. Furthermore, the refractive index Nd5 and Abbe number Vd5 of the fifth lens 5 satisfy: Nd5 > 1.51, Vd5 < 60. This design can effectively reduce chromatic aberration, optimize lens aberration, and thus effectively improve the imaging quality of the system. Furthermore, as a preferred embodiment of the present invention and not a limitation thereof, the relative illuminance of the maximum field of view of the optical system satisfies: RI ≥ 30%. By controlling the relative illuminance, the brightness of the edge field of view of the lens can be improved. Furthermore, as a preferred embodiment of the present invention and not a limitation thereof, the radius of curvature R1 of the object surface side of the first lens satisfies: R1 ≤ 30mm. By controlling the object surface side of the first lens 1, the total deflection angle of the object surface side of the first lens 1 at the edge field of view can be reasonably controlled within a reasonable range.
[0021] Furthermore, as a preferred embodiment of this utility model and not a limitation thereof, the third lens is made of glass, which can effectively improve the focal shift at high and low temperatures.
[0022] Furthermore, as a preferred embodiment of the present invention and not a limitation thereof, the total optical length (TTL) and aperture (FNO) of the optical system satisfy: TTL ≤ 23 mm, FNO ≤ 1.7. This design can reduce the total optical length, effectively miniaturize the lens, and increase the amount of light entering the system.
[0023] Furthermore, as a preferred embodiment of this utility model and not a limitation thereof, the horizontal field angle (FOV) of this optical system satisfies: FOV≥145°, and the maximum image circle satisfies: MIC≥6.9mm, which is beneficial for expanding the field of view and meeting the user's needs; Furthermore, as a preferred embodiment of the present invention and not a limitation thereof, the fourth lens and the fifth lens are bonded together to form a combined lens. This design increases the difference between the refractive index and the Abbe number of the lens, which can effectively reduce chromatic aberration.
[0024] Specifically, as a preferred embodiment of this utility model and not a limitation thereof, such as Figure 1-3As shown, in this embodiment 1, the focal length of the first lens 1 is f1 = -4.85mm, the focal length of the second lens 2 is f2 = 165mm, the focal length of the third lens 3 is f3 = 6.19mm, the focal length of the fourth lens 4 is f4 = -5.25mm, the focal length of the fifth lens 5 is f5 = 4.95mm, and the total optical length TTL is 22.679mm. The surface type, radius of curvature, thickness, and material parameters of each lens are shown in Table 1. Table 1: Basic parameters of the optical system in Example 1
[0025] In Table 1 above, along the optical axis from the object plane to the image plane, OBJ is the object plane; S1 and S2 correspond to the two surfaces of the first lens 1; S3 and S4 correspond to the two surfaces of the second lens 2; S5 and S6 correspond to the two surfaces of the third lens 3; S7 and S8 correspond to the two surfaces of the fourth lens 4; S8 and S9 correspond to the two surfaces of the fifth lens 5; STO is the location of the aperture stop; S10 and S11 correspond to the two surfaces of the filter; IMA corresponds to the image plane.
[0026] Furthermore, in Table 1, the surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formulas:
[0027] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the vertex of the surface, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the vertex of the aspherical surface, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th higher-order term in the aspherical surface shape formula. Table 2 gives the conic coefficients and higher-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for each aspherical surface in Example 1.
[0028] Table 2: Aspherical correlation values of the lens surface in Example 1
[0029] Figure 2 The astigmatism and distortion curves of the optical imaging lens of Example 1 are shown. Astigmatism represents the curvature of the meridional image plane and the curvature of the sagittal image plane, and distortion represents the distortion magnitude value corresponding to different image heights. Figure 3 The MTF curve of the optical imaging lens of Example 1 is shown, which represents the MTF values in the meridional and sagittal directions of different fields of view at different spatial frequencies. Figure 2 and Figure 3 It can be seen that the optical imaging system given in Example 1 can achieve good imaging quality and has higher imaging quality.
[0030] Specifically, as a preferred embodiment of this utility model and not a limitation thereof, such as Figure 4-6 As shown, in this embodiment 2, the focal length of the first lens 1 is f1 = -5.17mm, the focal length of the second lens 2 is f2 = 142mm, the focal length of the third lens 3 is f3 = 5.96mm, the focal length of the fourth lens 4 is f4 = -4.18mm, the focal length of the fifth lens 5 is f5 = 4.41mm, and the total optical length TTL is 22.676mm. The surface type, radius of curvature, thickness, and material parameters of each lens are shown in Table 3. Table 3: Basic parameters of the optical system in Example 2
[0031] In Table 3 above, along the optical axis from the object plane to the image plane, OBJ is the object plane; S1 and S2 correspond to the two surfaces of the first lens 1; S3 and S4 correspond to the two surfaces of the second lens 2; S5 and S6 correspond to the two surfaces of the third lens 3; S7 and S8 correspond to the two surfaces of the fourth lens 4; S8 and S9 correspond to the two surfaces of the fifth lens 5; STO is the location of the aperture stop; S10 and S11 correspond to the two surfaces of the filter; IMA corresponds to the image plane.
[0032] Furthermore, the surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formulas:
[0033] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the vertex of the surface, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the vertex of the aspherical surface, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th higher-order term in the aspherical surface shape formula. Table 4 gives the conic coefficients and higher-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for each aspherical surface in Example 2.
[0034] Table 4: Aspherical correlation values of the lens surface in Example 2
[0035] Figure 5 The astigmatism and distortion curves of the optical imaging lens in Example 2 are shown. Astigmatism represents the curvature of the meridional image plane and the curvature of the sagittal image plane, and distortion represents the magnitude of distortion at different image heights. Figure 6 The MTF curve of the optical imaging lens of Example 2 is shown, which represents the MTF values in the meridional and sagittal directions of different fields of view at different spatial frequencies. Figure 5 and Figure 6 It can be seen that the optical imaging system given in Example 2 can achieve good imaging quality and has higher imaging quality.
[0036] Specifically, as a preferred embodiment of this utility model and not a limitation thereof, such as Figure 7-9 As shown, in this embodiment 3, the focal length of the first lens 1 is f1 = -5.74mm, the focal length of the second lens 2 is f2 = 130mm, the focal length of the third lens 3 is f3 = 6.33mm, the focal length of the fourth lens 4 is f4 = -4.15mm, the focal length of the fifth lens 5 is f5 = 4.33mm, and the total optical length TTL is 22.679mm. The surface type, radius of curvature, thickness, and material parameters of each lens are shown in Table 5. Table 5: Basic parameters of the optical system in Example 3
[0037] In Table 5 above, along the optical axis from the object plane to the image plane, OBJ is the object plane; S1 and S2 correspond to the two surfaces of the first lens 1; S3 and S4 correspond to the two surfaces of the second lens 2; S5 and S6 correspond to the two surfaces of the third lens 3; S7 and S8 correspond to the two surfaces of the fourth lens 4; S8 and S9 correspond to the two surfaces of the fifth lens 5; STO is the location of the aperture stop; S10 and S11 correspond to the two surfaces of the filter; IMA corresponds to the image plane.
[0038] Furthermore, in Table 5, the object-side surface and image-side surface of any one of the second lens 2, the fourth lens 4, the fifth lens 5, and the sixth lens 6 are aspherical. The surface shape of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:
[0039] Where x is the distance from the corresponding point on the aspherical surface to the plane tangent to the vertex of the surface, h is the distance from the corresponding point on the aspherical surface to the optical axis, c is the curvature of the vertex of the aspherical surface, k is the conic coefficient, and Ai is the coefficient corresponding to the i-th higher-order term in the aspherical surface shape formula. Table 6 gives the conic coefficients and higher-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 of each aspherical surface that can be used in Example 3.
[0040] Table 6: Aspherical Correlation Values of Lens Surface in Example 3
[0041] Figure 8 The astigmatism and distortion curves of the optical imaging lens in Example 3 are shown. Astigmatism represents the curvature of the meridional image plane and the curvature of the sagittal image plane, and distortion represents the magnitude of distortion at different image heights. Figure 9 The MTF curve of the optical imaging lens of Example 3 is shown, which represents the MTF values in the meridional and sagittal directions of different fields of view at different spatial frequencies. Figure 8 and Figure 9 It can be seen that the optical imaging system given in Example 3 can achieve good imaging quality and has higher imaging quality.
[0042] Furthermore, in Examples 1-3, the basic data is as follows: Table 7: Basic Data for Examples 1-3
[0043] A camera module includes at least an optical lens. The optical system includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in sequence along the optical axis from the object plane to the image plane. By rationally allocating the surface shape and optical power of each lens, the lens aberrations are optimized, giving it excellent resolution, high pixel count, large aperture, no pyrolysis, day and night cofocus, and light weight, making it more competitive in the IPC market.
[0044] The above description provides one or more embodiments in conjunction with specific content, and does not imply that the specific implementation of this utility model is limited to these descriptions. Any methods or structures that are similar to or identical to those of this utility model, or any technical deductions or substitutions made based on the concept of this utility model, should be considered within the protection scope of this utility model.
Claims
1. A large-aperture optical system, comprising, sequentially from the object plane to the image plane along the optical axis, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens, characterized in that: The object plane of the first lens is convex, and the image plane is concave; its optical power is negative. The object side of the second lens is concave, and the image side is convex; its optical power is positive. The third lens has convex surfaces on both the object plane and the image plane, and its optical power is positive. The fourth lens has concave surfaces on both the object plane and the image plane, and its optical power is negative. The fifth lens has convex surfaces on both the object plane and image plane sides, and its optical power is positive.
2. The large aperture optical system according to claim 1, characterized in that: Each lens in this optical system satisfies the following condition: -13.5mm < f1 < -3.2mm; and / or 50mm < f2 < 200mm; Where f1 is the focal length of the first lens and f2 is the focal length of the second lens.
3. The large aperture optical system according to claim 1, characterized in that: Each lens in this optical system satisfies the following condition: 4.5mm < f3 < 8.2mm; and / or -6.5mm < f4 < -3.5mm; and / or 3.1mm < f5 < 7.5mm; Where f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f5 is the focal length of the fifth lens.
4. The large aperture optical system according to any one of claims 1-3, characterized in that: Each lens in this optical system satisfies the following condition: Nd1 > 1.7, Vd1 < 56; Nd2 > 1.6, Vd2 < 30; Nd3 > 1.51, Vd3 < 75; Nd4 > 1.6, Vd4 < 30; Nd5 > 1.51, Vd5 < 60; Wherein, Nd1 is the refractive index of the first lens, and Vd1 is the Abbe number of the first lens; Nd2 is the refractive index of the second lens, and Vd2 is the Abbe number of the second lens; Nd3 is the refractive index of the third lens, and Vd3 is the Abbe number of the third lens; Nd4 is the refractive index of the fourth lens, and Vd4 is the Abbe number of the fourth lens; Nd5 is the refractive index of the fifth lens, and Vd5 is the Abbe number of the fifth lens.
5. The large-aperture optical system according to any one of claims 1-3, characterized in that: The relative illumination of the maximum field of view of this optical system satisfies: RI ≥ 30%.
6. The large-aperture optical system according to any one of claims 1-3, characterized in that: The radius of curvature R1 on the object side of the first lens satisfies: R1 ≤ 30mm.
7. The large-aperture optical system according to any one of claims 1-3, characterized in that: The total optical length (TTL) and aperture of the system satisfy the following conditions: TTL ≤ 23mm, FNO ≤ 1.
7.
8. The large-aperture optical system according to any one of claims 1-3, characterized in that: The horizontal field angle (FOV) of the optical system satisfies: FOV≥145°, and the maximum image circle satisfies: MIC≥6.9mm.
9. The large aperture optical system according to claim 1, characterized in that: The aperture stop is positioned between the second lens and the third lens; and / or The fourth and fifth lenses are bonded together to form a combined lens.
10. A camera module, comprising at least an optical lens, characterized in that: The optical lens is equipped with the optical system according to any one of claims 1-9.