Optical lens
By optimizing the lens combination and aperture structure, the problem of high-definition imaging of miniaturized automotive camera lenses has been solved, achieving high definition and sharpness under miniaturized conditions, thus improving the driving experience and safety.
Patent Information
- Application Number
- CN202423243797.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-26
AI Technical Summary
As the resolution of automotive cameras increases, lenses require higher optical quality to maintain clarity and sharpness, but existing lenses are unable to meet the demands of high-definition imaging under miniaturization conditions.
The optical system employs a combination of multiple lenses, including lenses with negative and positive optical powers, combining aspherical and spherical designs, and optimizing the optical system by controlling the focal length ratio and aperture structure to improve sharpness and clarity.
While maintaining a compact lens size, it improves image clarity and sharpness, enhances the driving experience and road safety, is suitable for multiple occasions, and maintains good resolution in high and low temperature environments.
Smart Images
Figure CN223539069U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of optical imaging technology, and in particular to an optical lens. Background Technology
[0002] With technological advancements, the resolution of automotive surround-view cameras continues to improve. High-definition cameras provide more detailed images, helping drivers to more clearly identify details in their surroundings, such as pedestrians, vehicles, and obstacles. Furthermore, the rapid development of semiconductor technology has led to continuous improvements in image sensor manufacturing processes, making it possible to integrate more pixels onto smaller chips. Simultaneously, the growing market demand for intelligent, lightweight, and cost-effective vehicles is driving the development of automotive camera image sensors towards miniaturization and high performance.
[0003] As sensor sizes shrink, the pixel density of automotive cameras must increase to maintain the same resolution within a limited area. This requires lenses with higher optical quality to ensure that each pixel receives clear and detailed image information. Specifically, the lens needs to reduce optical defects such as aberrations and distortion to improve image clarity and sharpness. Utility Model Content
[0004] In order to overcome the shortcomings of existing automotive camera lenses in the market that cannot form high-quality optical images, and to improve the clarity and sharpness of camera images while keeping the size suitable for automotive installation, this application provides an optical lens.
[0005] The optical lens provided in this application adopts the following technical solution:
[0006] An optical lens has an object side and an image side arranged opposite each other along the optical axis, and a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, an infrared lens, and a protective glass are arranged sequentially from the object side to the image side. The lens is characterized in that: the first lens, the second lens, and the fifth lens all have negative optical power, and the third lens, the fourth lens, and the sixth lens all have positive optical power.
[0007] The object-side surface and the image-side surface of the first lens are both spherical, and the object-side surface is convex while the image-side surface is concave.
[0008] The object-side surface and the image-side surface of the second lens are both aspherical, and both the object-side surface and the image-side surface are concave.
[0009] The object-side surface and the image-side surface of the third lens are both spherical, and both the object-side surface and the image-side surface are both convex.
[0010] The object side and the image side of the fourth lens are both aspherical surfaces, and both the object side and the image side are convex surfaces;
[0011] The object side and the image side of the fifth lens are both aspherical surfaces, and both the object side and the image side are concave surfaces;
[0012] The object side and the image side of the sixth lens are both aspherical surfaces, and both the object side and the image side are convex surfaces.
[0013] By adopting the above technical solutions and combining the above multiple lenses, it is possible to effectively improve the clarity and sharpness of the optical lens on the vehicle-mounted camera while keeping the volume of the vehicle-mounted camera unchanged, thereby forming high-quality images, improving the driving experience and driving safety of users, and making up for the defect that the vehicle-mounted camera cannot have a high-definition view due to its small volume.
[0014] Optionally, the total effective focal length of the optical lens is F, the focal length of the first lens is F1, and the focal length of the third lens is F3. Among them, 7.2 < |F1 / F| < 8.4, and 5.4 < F3 / F < 6.6.
[0015] By adopting the above technical solutions, by reasonably controlling the value of F1 / F, the head aperture of the system can be reduced, making the lens aperture smaller; at the same time, by adjusting the ratio of F3 / F, it can be ensured that the optical system has good resolution at high and low temperatures, improving the practicality of the optical lens on the vehicle-mounted camera.
[0016] Optionally, the entrance pupil diameter of the optical lens is EPD, and the distance along the optical axis from the intersection of the object side of the first lens and the optical axis to the system imaging plane is TTL. Among them, 1.65 < F / EPD < 1.71, and 17.9 < TTL / F < 19.6.
[0017] By adopting the above technical solutions, reasonably controlling the ratio of the effective focal length to the entrance pupil diameter can increase the F-number of the system, thereby increasing the depth of field of the system, so that objects within a certain range can form clear images.
[0018] Optionally, the radius of curvature of the object side of the third lens is R31, and 3 < R31 / F3 < 15.2.
[0019] By adopting the above technical solutions, controlling this ratio can ensure that the sensitivity of the third lens is small.
[0020] Optionally, the perpendicular distance from the effective diameter of the object side of the first lens to the optical axis is SD1, and 0.9 < |SD1 / F1| < 1.1.
[0021] By adopting the above technical solutions, controlling this ratio can ensure that the head aperture ratio of the lens is small.
[0022] Optionally, the distance from the intersection of the object side of the first lens and the optical axis to the intersection of the image side of the third lens and the optical axis is CT13, and the overall focal length from the first lens to the third lens is F13, where 0.04 < |CT13 / F13| < 1.3.
[0023] By adopting the above technical solution, controlling this ratio ensures that the front lens group of the aperture stop has a reasonable structure.
[0024] Optionally, the distance from the intersection of the object-side surface of the fourth lens and the optical axis to the intersection of the image-side surface of the sixth lens and the optical axis is CT46, and the overall focal length from the fourth lens to the sixth lens is F46, where 1.2 <CT46 / F46<1.4。
[0025] By adopting the above technical solution, controlling this ratio ensures that the lens group behind the aperture has a reasonable structure.
[0026] Optionally, the distance from the intersection of the image-side surface of the third lens and the optical axis to the intersection of the object-side surface of the fourth lens and the optical axis is CT34, and the distance from the intersection of the object-side surface of the third lens and the optical axis to the intersection of the image-side surface of the third lens and the optical axis is CT3, where 0.2 <CT34 / CT3<0.6。
[0027] By adopting the above technical solution, controlling this ratio ensures that the sensitivity of the third lens is relatively small.
[0028] Optionally, the radius of curvature of the image-side surface of the second lens is R22, and the radius of curvature of the object-side surface of the third lens is R31, wherein 0.01 <R22 / R31<0.11。
[0029] By adopting the above technical solution, this ratio is controlled to ensure that the relative eccentricity sensitivity of the second and third lenses is relatively small.
[0030] Optionally, an aperture for controlling the light propagation path and the amount of light passing through is also fixedly installed between the third lens and the fourth lens.
[0031] By adopting the above technical solution, the aperture is mainly used to adjust the intensity of the passing light beam and control the imaging quality. When the thickness of the aperture increases, the propagation path of the light beam will change, which may cause more light to be blocked, affecting the brightness and contrast of the image.
[0032] In summary, this application includes at least one of the following beneficial technical effects:
[0033] 1. By combining lenses of different specifications, this application can ensure clarity and sharpness while maintaining a small overall size of the optical lens, making it easier for car owners to observe the scene around the vehicle in more detail and improving driving safety.
[0034] 2. By using different types of lenses in combination, this application can flexibly change the sharpness and size of the optical lens, making the optical lens applicable to more occasions and enhancing the practical value of the product.
[0035] 3. This application adds an aperture stop between the third lens and the fourth lens, thereby effectively controlling the amount of light entering the optical lens, so as to form a more balanced imaging effect in terms of brightness and contrast on the vehicle display screen. Attached Figure Description
[0036] Figure 1 This is an overall schematic diagram of one embodiment of an optical lens according to this application.
[0037] Figure 2 This is an overall schematic diagram of a second embodiment of an optical lens according to this application.
[0038] Figure 3 This is an overall schematic diagram of an embodiment three of an optical lens according to this application.
[0039] Figure 4 This is an overall schematic diagram of an embodiment four of an optical lens according to this application.
[0040] Explanation of reference numerals in the attached diagram: 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Infrared lens; 8. Protective glass; 9. Aperture. Detailed Implementation
[0041] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.
[0042] This application discloses an optical lens.
[0043] Reference Figure 1-4, An optical lens has an object side and an image side that are oppositely arranged along the optical axis direction. Among them, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, an infrared lens 7, and a protective glass 8 are arranged in sequence from the object side to the image side. The functions of the infrared lens 7 and the protective glass 8 are to conduct optical signals and divide the image side of the optical lens on the camera and the signal receiving structure respectively. Specifically, the first lens 1, the second lens 2, and the fifth lens 5 all have negative optical powers, and the third lens 3, the fourth lens 4, and the sixth lens 6 all have positive optical powers. The multiple lenses act together to form a stable and clear object image.
[0044] Refer to Figure 1-4 , Further, the object side surface and the image side surface of the first lens 1 are both spherical surfaces, and its object side surface is a convex surface and the image side surface is a concave surface; the object side surface and the image side surface of the second lens 2 are both aspherical surfaces, and both its object side surface and the image side surface are concave surfaces; the object side surface and the image side surface of the third lens 3 are both spherical surfaces, and both its object side surface and the image side surface are convex surfaces; the object side surface and the image side surface of the fourth lens 4 are both aspherical surfaces, and both its object side surface and the image side surface are convex surfaces; the object side surface and the image side surface of the fifth lens 5 are aspherical surfaces, and both its object side surface and the image side surface are concave surfaces; the object side surface and the image side surface of the sixth lens 6 are both aspherical surfaces, and both its object side surface and the image side surface are convex surfaces.
[0045] Refer to Figure 1-4 , The total effective focal length of the optical lens is F, and the focal lengths of the first lens 1 and the third lens 3 are F1 and F3 respectively. Then 7.2 < |F1 / F| < 8.4, and 5.4 < F3 / F < 6.6.
[0046] Specifically, by reasonably controlling the value of F1 / F, the head aperture of the system can be reduced, making the lens aperture smaller, which is beneficial to reducing the overall size of the optical lens and not occupying too much installation space on the vehicle. Controlling the ratio of F3 / F can ensure that the optical system has good resolution ability under high and low temperature conditions, improving the clarity and imaging quality of the final image of the optical lens.
[0047] Refer to Figure 1-4 , Further, the entrance pupil diameter of the optical lens is EPD, and the distance along the optical axis from the intersection point of the object side surface of the first lens 1 and the optical axis to the system imaging surface is TTL. Then 1.65 < F / EPD < 1.71, and 17.9 < TTL / F < 19.6.
[0048] Specifically, controlling the ratio of F / EPD can increase the depth of field of the system, so that objects within a certain range can form clear images. Controlling the ratio of TTL / F can ensure a long depth of field while ensuring that the overall lens has a small size, enabling objects at different distances to form clear images.
[0049] Refer to Figure 1-4 Furthermore, if the radius of curvature of the object side surface of the third lens 3 is R31, then 3 < R31 / F3 < 15.2. The perpendicular distance between the effective diameter of the object side surface of the first lens 1 and the optical axis is SD1, then 0.9 < |SD1 / F1| < 1.1.
[0050] Specifically, controlling the ratio of R31 / F3 ensures that the sensitivity of the third lens 3 is relatively small, improving the ability of the camera to process object images in real time. Controlling the ratio of |SD1 / F1| can ensure that the head aperture of the lens is relatively small, reducing the aperture at the end of the optical lens.
[0051] Refer to Figure 1-4 , the distance between the intersection point of the object side surface of the first lens 1 and the optical axis and the intersection point of the image side surface of the third lens 3 and the optical axis is CT13, and the overall focal length from the first lens 1 to the third lens 3 is F13, then 0.04 < |CT13 / F13| < 1.3.
[0052] Specifically, controlling the ratio of CT13 / F13 can ensure that the front lens group of the diaphragm 9 has a reasonable structure, avoiding blurring of the generated object images.
[0053] Refer to Figure 1-4 , further, the distance between the intersection point of the object side surface of the fourth lens 4 and the optical axis and the intersection point of the image side surface of the sixth lens 6 and the optical axis is CT46, and the overall focal length from the fourth lens 4 to the sixth lens 6 is F46, then 1.2 < CT46 / F46 < 1.4.
[0054] Specifically, controlling the ratio of CT46 / F46 ensures that the rear lens group of the diaphragm 9 has a reasonable structure to avoid blurring of the generated object images.
[0055] Refer to Figure 1-4 , the distance between the intersection point of the image side surface of the third lens 3 and the optical axis and the intersection point of the fourth lens 4 and the optical axis is CT34, and the distance between the intersection point of the object side surface of the third lens 3 and the optical axis and the intersection point of the image side surface of the third lens 3 and the optical axis is CT3, then 0.2 < CT34 / CT3 < 0.6.
[0056] Specifically, adjusting the ratio of CT34 / CT3 is mainly used to ensure that the sensitivity of the third lens 3 is relatively small.
[0057] Refer to Figure 1-4 , the radius of curvature of the image side surface of the second lens 2 is R22, and the radius of curvature of the object side surface of the third lens 3 is R31, then 0.01 < R22 / R31 < 0.11.
[0058] Specifically, controlling the ratio of R22 / R31 ensures that the relative eccentricity sensitivity of the second lens 2 and the third lens 3 is relatively small, improving the focusing ability of the optical lens.
[0059] Refer to Figure 1-4 An aperture stop 9, used to control the light propagation path and the amount of light passing through, is fixedly installed between the third lens 3 and the fourth lens 4. The thickness of the aperture stop 9 has a significant impact on the image quality. The thickness of the aperture stop 9 affects the optical path, and thus the image quality. Specifically, the thickness of the aperture stop 9 affects the structure and diffraction properties of the light beam, thereby affecting the sharpness and resolution of the image.
[0060] However, those skilled in the art should understand that, without departing from the technical solutions claimed in this application, the number of lenses constituting the lens can be changed to obtain the various results and advantages described in this specification.
[0061] The following describes in further detail, with reference to the accompanying drawings, specific embodiments and implementation schemes of the optical lens applicable to the above-described embodiments.
[0062] Example 1
[0063] Table 1 shows the preferred parameters of each lens in Embodiment 1, including Y-radius, thickness, material, refractive index, Abbe number, and focal length. The units for the length quantities are all mm.
[0064]
[0065] Table 1
[0066] This embodiment uses six lenses as an example. By rationally allocating the optical power and surface shape of each lens, the center thickness of each lens, and the air gap between each lens, the lens can possess at least one of the following beneficial effects: small FNO, high resolution, low distortion, strong thermal stability, and small principal ray angle. The surface shape Z of each lens is defined by the following formula:
[0067]
[0068] Where Z is the distance vector from the vertex of the aspherical surface at a height of h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient coni.c; A, B, C, D, and E are all higher-order coefficients.
[0069] Table 2 below shows the specific values of the conic coefficient k and the higher-order coefficients A4-A20 for the lens surfaces S3-S4 and S8-S13 that can be used in Example 1.
[0070]
[0071] Table 2
[0072] According to the specific solution in this embodiment, the following effects can be achieved:
[0073] EFL (Effective Focal Length) = 0.73, FNO (Aperture No.) = 1.67, FOV (Field of View) = 200°.
[0074] Example 2
[0075] Table 3 shows the preferred parameters of each lens in Example 2, including Y-radius, thickness, material, refractive index, Abbe number, and focal length. The units for the lengths are all in mm.
[0076]
[0077] Table 3
[0078] This embodiment uses six lenses as an example. By rationally allocating the optical power and surface shape of each lens, the center thickness of each lens, and the air gap between each lens, the lens can possess at least one of the following beneficial effects: small FNO, high resolution, low distortion, strong thermal stability, and small principal ray angle. The surface shape Z of each aspherical surface is defined by the following formula:
[0079]
[0080] Where Z is the distance vector from the vertex of the aspherical surface along the optical axis at a height of h; c is the paraxial curvature of the aspherical surface, c = 1 / R (that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; A, B, C, D, and E are all higher-order coefficients.
[0081] Table 4 below shows the specific values of the conic coefficient k and the higher-order coefficients A4-A20 for the lens surfaces S3-S4 and S8-S13 that can be used in Example 2.
[0082]
[0083] Table 4
[0084] According to the specific solution in this embodiment, the following effects can be achieved:
[0085] EFL (Effective Focal Length) = 0.7, FNO (Aperture No.) = 1.66, FOV (Field of View) = 200°.
[0086] Example 3
[0087] Table 5 shows the preferred parameters of each lens in Example 3, including Y-radius, thickness, material, refractive index, Abbe number, and focal length. The units for the lengths are all in mm.
[0088]
[0089] Table 5
[0090] This embodiment uses six lenses as an example. By rationally allocating the optical power and surface shape of each lens, the center thickness of each lens, and the air gap between each lens, the lens can possess at least one of the following beneficial effects: small FNO, high resolution, low distortion, strong thermal stability, and small principal ray angle. The surface shape Z of each aspherical surface is defined by the following formula:
[0091]
[0092] Where Z is the distance vector from the vertex of the aspherical surface along the optical axis at a height of h; c is the paraxial curvature of the aspherical surface, c = 1 / R (that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; A, B, C, D, and E are all higher-order coefficients.
[0093] Table 6 below shows the specific values of the conic coefficient k and the higher-order coefficients A4-A20 for the lens surfaces S3-S4 and S8-S13 that can be used in Example 3.
[0094] Table 6
[0095] According to the specific solution in this embodiment, the following effects can be achieved:
[0096] EFL (Effective Focal Length) = 0.64, FNO (Aperture No.) = 1.7, FOV (Field of View) = 200°.
[0097] Example 4
[0098] Table 7 shows the preferred parameters of each lens in Embodiment 4, including Y-radius, thickness, material, refractive index, Abbe number, and focal length. The units for the length quantities are all mm.
[0099]
[0100] Table 7
[0101] This embodiment uses six lenses as an example. By rationally allocating the optical power and surface shape of each lens, the center thickness of each lens, and the air gap between each lens, the lens can possess at least one of the following beneficial effects: small FNO, high resolution, low distortion, strong thermal stability, and small principal ray angle. The surface shape Z of each aspherical surface is defined by the following formula:
[0102]
[0103] Where Z is the distance vector from the vertex of the aspherical surface along the optical axis at a height of h; c is the paraxial curvature of the aspherical surface, c = 1 / R (that is, the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; A, B, C, D, and E are all higher-order coefficients.
[0104] Table 8 below shows the specific values of the conic coefficient k and the higher-order coefficients A4-A20 for the lens surfaces S3-S4 and S8-S13 that can be used in Example 4.
[0105]
[0106] Table 8
[0107] According to the specific solution in this embodiment, the following effects can be achieved:
[0108] EFL (Effective Focal Length) = 0.69, FNO (Aperture No.) = 1.67, FOV (Field of View) = 200°.
[0109] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. An optical lens having an object side and an image side arranged opposite each other along the optical axis, and having a first lens (1), a second lens (2), a third lens (3), a fourth lens (4), a fifth lens (5), a sixth lens (6), an infrared lens (7), and a protective glass (8) arranged sequentially from the object side to the image side, characterized in that: The first lens (1), the second lens (2), and the fifth lens (5) all have negative optical powers, and the third lens (3), the fourth lens (4), and the sixth lens (6) all have positive optical powers. Among them, Both the object side and the image side of the first lens (1) are spherical surfaces, and its object side is a convex surface while the image side is a concave surface; Both the object side and the image side of the second lens (2) are aspherical surfaces, and both its object side and image side are concave surfaces; Both the object side and the image side of the third lens (3) are spherical surfaces, and both its object side and image side are convex surfaces; Both the object side and the image side of the fourth lens (4) are aspherical surfaces, and both its object side and image side are convex surfaces; Both the object side and the image side of the fifth lens (5) are aspherical surfaces, and both its object side and image side are concave surfaces; Both the object side and the image side of the sixth lens (6) are aspherical surfaces, and both its object side and image side are convex surfaces.
2. An optical lens according to claim 1, characterized in that: The total effective focal length of the optical lens is F, the focal length of the first lens (1) is F1, and the focal length of the third lens (3) is F3. Among them, 7.2 < |F1 / F| < 8.4, and 5.4 < F3 / F < 6.
6.
3. An optical lens according to claim 2, characterized in that: The entrance pupil diameter of the optical lens is EPD, and the distance along the optical axis from the intersection point of the object side of the first lens (1) and the optical axis to the system imaging plane is TTL. Among them, 1.65 < F / EPD < 1.71, and 17.9 < TTL / F < 19.
6.
4. An optical lens according to claim 2, characterized in that: The radius of curvature of the object side of the third lens (3) is R31, and 3 < R31 / F3 < 15.
2.
5. An optical lens according to claim 2, characterized in that: The perpendicular distance from the effective diameter of the object side of the first lens (1) to the optical axis is SD1, and 0.9 < |SD1 / F1| < 1.
1.
6. An optical lens according to claim 1, characterized in that: The distance from the intersection point of the object side of the first lens (1) and the optical axis to the intersection point of the image side of the third lens (3) and the optical axis is CT13, and the overall focal length from the first lens (1) to the third lens (3) is F13. Among them, 0.04 < |CT13 / F13| < 1.
3.
7. An optical lens according to claim 6, characterized in that: The distance from the intersection point of the object side of the fourth lens (4) and the optical axis to the intersection point of the image side of the sixth lens (6) and the optical axis is CT46, and the overall focal length from the fourth lens (4) to the sixth lens (6) is F46. Among them, 1.2 < CT46 / F46 < 1.
4.
8. An optical lens according to claim 1, characterized in that: The distance from the intersection point of the image side of the third lens (3) and the optical axis to the intersection point of the object side of the fourth lens (4) and the optical axis is CT34, and the distance from the intersection point of the object side of the third lens (3) and the optical axis to the intersection point of the image side of the third lens (3) and the optical axis is CT3. Among them, 0.2 < CT34 / CT3 < 0.
6.
9. An optical lens according to claim 1, characterized in that: The radius of curvature of the image side of the second lens (2) is R22, and the radius of curvature of the object side of the third lens (3) is R31. Among them, 0.01 < R22 / R31 < 0.
11.
10. An optical lens according to claim 1, characterized in that: A diaphragm (9) for controlling the light propagation path and the light passing amount is fixedly installed between the third lens (3) and the fourth lens (4).