An optical imaging system, camera module and electronic device

Abstract

The application relates to the field of camera technology, in particular to an optical imaging system, a camera module and electronic equipment. The optical imaging system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in sequence from an object side to an image side along an optical axis. The first lens has a negative refractive power, and the object side surface of the first lens is a convex surface. The second lens has a positive refractive power. The third lens has a negative refractive power, and the object side surface of the third lens is a convex surface. The fourth lens has a positive refractive power. The object side surface of the sixth lens is a binary surface. The optical imaging system satisfies the following relationship: tan FOV / Fno>0.25; wherein FOV is the field of view angle of the optical imaging system; and Fno is the aperture of the optical imaging system. The optical imaging system provided in the embodiment has a large relative aperture, can adapt to a large temperature difference environment, can comprehensively and reliably acquire environmental information under a complex driving environment, and improves driving safety.

Description

Technical Field

[0001] This application relates to the field of camera technology, and more particularly to an optical imaging system, camera module, and electronic device. Background Technology

[0002] The driving environment of automobiles is complex. The vehicle's operating system uses onboard LiDAR receivers to acquire real-time information about the external environment, enabling drivers to react promptly and improve driving safety. Currently, the relative aperture of onboard LiDAR receivers on the market is limited, resulting in a narrow field of view and limited environmental information acquisition. Furthermore, driving environments with significant temperature variations can severely impact the image quality of these receivers. Therefore, improving the performance of onboard LiDAR receivers to comprehensively and reliably acquire information about the driving environment is a pressing technical challenge. Summary of the Invention

[0003] This application solves the technical problem of how to improve the performance of the receiving lens of an on-board LiDAR to comprehensively and reliably acquire information about the driving environment by providing an optical imaging system, a camera module, and an electronic device.

[0004] In a first aspect, this application provides an optical imaging system for use in a vehicle-mounted lidar receiving lens, the optical imaging system comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side;

[0005] The first lens has negative refractive power, and the object-side surface of the first lens is convex.

[0006] The second lens has positive refractive power;

[0007] The third lens has negative refractive power, and the object-side surface of the third lens is convex.

[0008] The fourth lens has positive refractive power;

[0009] The object-side surface of the sixth lens is a binary surface;

[0010] The optical imaging system satisfies the following relationship:

[0011] tanFOV / Fno>0.25;

[0012] Wherein, FOV is the field of view of the optical imaging system; Fno is the aperture of the optical imaging system.

[0013] As an optional implementation, the optical imaging system satisfies the following relationship:

[0014] |EA2-EA4|≤90;

[0015] Wherein, EA2 is the second-order binary surface coefficient of the binary surface; EA4 is the fourth-order binary surface coefficient of the binary surface.

[0016] As an optional implementation, an aperture stop is provided between the third lens and the fourth lens.

[0017] As an optional implementation, the optical imaging system satisfies the following relationship:

[0018] 1 / (f1 / 1000)+1 / (f2 / 1000)+1 / (f3 / 1000)+1 / (f4 / 1000)>

[0019] 1 / (f5 / 1000)+1 / (f6 / 1000);

[0020] 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; f5 is the focal length of the fifth lens; and f6 is the focal length of the sixth lens.

[0021] As an optional implementation, the optical imaging system satisfies the following relationship:

[0022] f1<0, f2>0, f3<0, f4>0;

[0023] 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; and f4 is the focal length of the fourth lens.

[0024] As an optional implementation, the optical imaging system satisfies the following relationship:

[0025] |G6R1|>15;

[0026] Wherein, G6R1 is the radius of curvature of the object-side surface of the sixth lens.

[0027] As an optional implementation, the optical imaging system satisfies the following relationship:

[0028] 1.5*(CT4+CT5) <CT6<2.5*(CT4+CT5);

[0029] Wherein, CT4 is the lens thickness of the fourth lens; CT5 is the lens thickness of the fifth lens; and CT6 is the lens thickness of the sixth lens.

[0030] As an optional implementation, the optical imaging system satisfies the following relationship:

[0031] N2>1.85;

[0032] Where N2 is the refractive index of the second lens.

[0033] Secondly, this application provides a camera module, the camera module including an image sensor and an optical imaging system as described in any of the first aspects, the image sensor being disposed on the image side of the optical imaging system.

[0034] Thirdly, this application provides an electronic device, the electronic device including a housing and a camera module as described in the second aspect, the camera module being disposed within the housing.

[0035] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0036] In this embodiment of the invention, an optical imaging system for a vehicle-mounted lidar receiving lens is provided. The optical imaging system includes: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side; the first lens has negative refractive power, and the object side surface of the first lens is convex; the second lens has positive refractive power; the third lens has negative refractive power, and the object side surface of the third lens is convex; the fourth lens has positive refractive power; the object side surface of the sixth lens is a binary surface; the optical imaging system satisfies the following relationship: tanFOV / Fno>0.25; where FOV is the field of view of the optical imaging system; and Fno is the aperture of the optical imaging system.

[0037] This embodiment improves image quality by designing convex and concave surfaces for each lens within the optical imaging system. Utilizing the refractive properties of the lenses, it corrects distortion, dispersion, and field curvature. Since incident light undergoes chromatic aberration as it passes sequentially from the object side to the image side through the first to the fifth lens, the object side of the sixth lens is designed as a binary surface. The binary surface on the object side of the sixth lens corrects the chromatic aberration caused by the first to fifth lenses through its refraction and diffraction. Because the binary surface corrects the chromatic aberration caused by the first to fifth lenses, there is no need to consider chromatic aberration correction separately when setting the parameters of the first to fifth lenses. Furthermore, the refraction and diffraction of the binary surface helps reduce blur spots in the image, making the image energy source more concentrated, thus facilitating the design of ultra-large relative aperture optical imaging systems. Simultaneously, since the thermal drift characteristics of the binary surface are opposite to those of the lenses, it can compensate for temperature drift caused by changes in temperature between the first and fifth lenses, allowing the optical imaging system to better adapt to environments with large temperature differences. Finally, since the larger the ratio between the tangent of the field of view and the aperture, the greater the amount of information and the richer the details that the optical imaging system can capture, this embodiment sets tanFOV / Fno>0.25; where FOV is the field of view of the optical imaging system and Fno is the aperture of the optical imaging system, so that the optical imaging system can obtain a larger field of view and thus acquire more information.

[0038] The optical imaging system provided in this embodiment has a large relative aperture and can adapt to environments with large temperature differences, thereby achieving the technical effect of comprehensively and reliably acquiring environmental information under complex driving conditions and improving driving safety. Attached Figure Description

[0039] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference figures denote the same parts throughout the drawings.

[0040] In the attached diagram:

[0041] Figure 1 A schematic diagram of the optical imaging system structure of Embodiment 1 of the present invention is shown;

[0042] Figure 2 An image plane dot diagram of the optical imaging system of Embodiment 1 of the present invention is shown;

[0043] Figure 3 An axial aberration curve of the optical imaging system of Embodiment 1 of the present invention is shown;

[0044] Figure 4 The field curvature / distortion curve of the optical imaging system of Embodiment 1 of the present invention is shown;

[0045] Figure 5 A stray light analysis diagram of the binary surface of the optical imaging system of Embodiment 1 of the present invention is shown;

[0046] Figure 6 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at 25°C is shown;

[0047] Figure 7 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at -100°C is shown;

[0048] Figure 8 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at -60°C is shown;

[0049] Figure 9 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at -20°C is shown;

[0050] Figure 10 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at 20°C is shown.

[0051] Figure 11 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at 60°C is shown;

[0052] Figure 12 The encirclement energy diagram of the optical imaging system of Embodiment 1 of the present invention at 100°C is shown;

[0053] Figure 13 A schematic diagram of the camera module according to Embodiment 2 of the present invention is shown;

[0054] Figure 14 A schematic diagram of the structure of the electronic device according to Embodiment 3 of the present invention is shown. Detailed Implementation

[0055] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0056] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0058] This addresses the technical challenge of improving the performance of vehicle-mounted LiDAR receivers to comprehensively and reliably acquire information about the driving environment.

[0059] Firstly, this application provides an optical imaging system for use in a vehicle-mounted LiDAR receiving lens. Please refer to the appendix. Figure 1 The optical imaging system has an object plane 11 and an imaging plane Q15 on both sides. The optical imaging system includes a first lens G1, a second lens G2, a third lens G3, an aperture stop Q10, a fourth lens G4, a fifth lens G5, and a sixth lens G6 arranged sequentially along the optical axis from the object side to the image side.

[0060] As an optional implementation, an aperture stop Q10 is provided between the third lens G3 and the fourth lens G4 in this embodiment. The first to third lenses G3 before the aperture stop Q10 are mainly used to acquire and converge the incident light, while the fourth to sixth lenses G6 after the aperture stop Q10 are mainly used to correct aberrations. Positioning the aperture stop Q10 between the third lens G3 and the fourth lens G4 avoids some of the light rays converged by the first to third lenses G3 from directly entering the imaging plane without passing through the fourth to sixth lenses G4, thus preventing ghosting and improving image quality.

[0061] The aperture stop Q10 can be either an aperture stop or a field stop, depending on the specific circumstances of the implementation, and is not limited here.

[0062] In this embodiment, the first lens G1 is a negative meniscus lens with negative refractive power, and the second lens G2 is a positive meniscus lens with positive refractive power.

[0063] A positive meniscus lens is one in which both optical surfaces perpendicular to the optical axis are convex; a negative meniscus lens is one in which one optical surface is convex and the other is concave.

[0064] The object side of the first lens G1 is convex, and the image side of the first lens G1 is adjacent to the object side of the second lens G2. The sagittal directions formed by the two are opposite. By setting the lens structure parameters of the first lens G1 and the second lens G2, a large difference in aperture between the first lens G1 and the second lens G2 is made, which is beneficial to correct distortion.

[0065] The third lens G3 is a negative meniscus lens with negative refractive power; the object side of the third lens G3 is convex. The fourth lens G4 is a positive meniscus lens with positive refractive power. The image plane side of the third lens G3 and the object plane side of the fourth lens G4 are adjacent, and the sagittal directions formed by them are opposite. By setting the lens structure parameters of the third lens G3 and the fourth lens G4, a large difference in aperture between the third lens G3 and the fourth lens G4 is beneficial for correcting distortion.

[0066] This embodiment improves imaging quality by designing the convex and concave sides of each lens in the optical imaging system and utilizing the refractive effect of the lenses to correct the distortion, dispersion, and field curvature of thermal light step by step.

[0067] Because incident light undergoes chromatic aberration as it passes sequentially from the object side to the image side through the first to the fifth lenses, the object side of the sixth lens is designed as a binary surface. The chromatic aberration caused by the first to the fifth lenses is corrected by the refraction and diffraction of the binary surface on the object side of the sixth lens. Since the binary surface corrects the chromatic aberration caused by the first to the fifth lenses, there is no need to consider chromatic aberration correction separately when setting the parameters of the first to the fifth lenses. Furthermore, the refraction and diffraction of the binary surface helps reduce blur spots in the image, making the image energy source more concentrated, thus facilitating the design of ultra-large relative aperture optical imaging systems. Simultaneously, because the thermal drift characteristics of the binary surface are opposite to those of the lenses, it can compensate for temperature drift caused by changes in temperature between the first and fifth lenses, allowing the optical imaging system to better adapt to environments with large temperature differences.

[0068] The optical imaging system provided in this embodiment satisfies the following relationship:

[0069] tanFOV / Fno>0.25;

[0070] Wherein, FOV is the field of view of the optical imaging system; Fno is the aperture of the optical imaging system.

[0071] The larger the ratio between the tangent of the field of view and the aperture, the more information the optical imaging system can capture and the richer the details. Therefore, in this embodiment, the optical imaging system obtains a larger amount of information by setting tanFOV / Fno>0.25.

[0072] In the optical imaging system provided in this embodiment, the incident light reflected from the object surface Q1 passes sequentially through the object-side surface Q2 and image-side surface Q3 of the first lens G1, the object-side surface Q4 and image-side surface Q5 of the second lens G2, the object-side surface Q6 and image-side surface Q7 of the third lens G3, the aperture Q10, the object-side surface Q9 and image-side surface Q10 of the fourth lens G4, the object-side surface Q11 and image-side surface Q12 of the fifth lens G5, and the binary surface Q13 of the sixth lens G6. After being refracted by the binary surface Q13, the light exits from the image-side surface Q14 of the sixth lens G6 and is projected onto the imaging surface Q15 adjacent to the sixth lens G6.

[0073] As an optional implementation, the optical imaging system satisfies the following relationship:

[0074] |EA2-EA4|≤90;

[0075] Wherein, EA2 is the second-order binary surface coefficient of the binary surface; EA4 is the fourth-order binary surface coefficient of the binary surface.

[0076] The difference between the second-order and fourth-order binary surface coefficients of the binary surface is less than a certain value, resulting in a sufficiently large annular band width, which is beneficial for machining the binary surface on the filter. Experimental results from multiple optical experiments show that controlling the difference between the second-order and fourth-order binary surface coefficients to be less than 90 facilitates machining the binary surface on the filter and also achieves a sufficiently large annular band width. Therefore, |EA2-EA4|≤90 should be controlled.

[0077] As an optional implementation, the optical imaging system satisfies the following relationship:

[0078] 1 / (f1 / 1000)+1 / (f2 / 1000)+1 / (f3 / 1000)+1 / (f4 / 1000)>

[0079] 1 / (f5 / 1000)+1 / (f6 / 1000);

[0080] 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; f5 is the focal length of the fifth lens; and f6 is the focal length of the sixth lens.

[0081] Since the first to third lenses G1 before the aperture stop Q10 are mainly used to acquire and converge the incident light, and the fourth to sixth lenses G4 after the aperture stop Q10 are mainly used to correct aberrations, it is more beneficial for aberration correction if the sum of the focal lengths of the first to third lenses G1 before the aperture stop Q10 is greater than the sum of the focal lengths of the fourth to sixth lenses G4 after the aperture stop Q10.

[0082] As an optional implementation, the optical imaging system satisfies the following relationship:

[0083] f1<0, f2>0, f3<0, f4>0;

[0084] 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; and f4 is the focal length of the fourth lens.

[0085] The image-side surface Q3 of the first lens G1 is concave, and the object-side surface Q4 of the second lens G2 is convex. The first incident light is received through this concave-convex combination of the image-side surface Q3 of the first lens G1 and the object-side surface Q4 of the second lens G2. The image-side surface Q7 of the third lens G3 is concave, and the object-side surface Q9 of the fourth lens G4 is convex. The second incident light is received through this concave-convex combination of the image-side surface Q7 of the third lens G3 and the object-side surface Q9 of the fourth lens G4, and this process compensates for the spherical aberration of the first lens G1. This two-stage light reception allows the light to enter the optical imaging system more smoothly, reducing coma and astigmatism caused by excessive light reversal angles.

[0086] As an optional implementation, the optical imaging system satisfies the following relationship:

[0087] |G6R1|>15;

[0088] Wherein, G6R1 is the radius of curvature of the object side surface of the sixth lens G6.

[0089] The larger the radius of curvature of the lens's optical surface, the smaller the slope of the optical surface, which facilitates the machining of the binary surface Q13 on the object side of the sixth lens. Furthermore, the larger the radius of curvature of the lens's optical surface, the smaller the deflection angle of light passing through the sixth lens G6, reducing the sensitivity of the optical imaging system and improving image quality. A smaller surface slope of the lens is more conducive to reducing stray light reflection and improving the utilization rate of effective light energy, thereby enhancing radar detection performance.

[0090] As an optional implementation, the optical imaging system satisfies the following relationship:

[0091] 1.5*(CT4+CT5) <CT6<2.5*(CT4+CT5);

[0092] Wherein, CT4 is the lens thickness of the fourth lens; CT5 is the lens thickness of the fifth lens; and CT6 is the lens thickness of the sixth lens.

[0093] The thickness of the sixth lens G6 is kept within a certain range, which helps to control the principal ray angle of the optical imaging system, improve the relative illumination of the optical system, and avoid vignetting when imaging on the imaging surface made of the photosensitive chip.

[0094] As an optional implementation, the optical imaging system satisfies the following relationship:

[0095] N2>1.85;

[0096] Where N2 is the refractive index of the second lens.

[0097] When producing lenses with very large relative apertures, spherical aberration is one of the main factors affecting the size of the image blur spot and the concentration of the captured energy. Using a material with a high refractive index to manufacture the second lens G2 is beneficial for correcting the lens's spherical aberration.

[0098] Table 1 below lists the lens performance parameters for the corresponding optical imaging system:

[0099] Table 1:

[0100]

[0101] Table 2 below provides the bidimensional surface parameter data for an exemplary system:

[0102] Table 2:

[0103]

[0104] Table 3 below provides lens structure data for an exemplary optical imaging system:

[0105] Table 3:

[0106] As attached Figure 2 This is a point diagram of the image plane of an optical imaging system with the aforementioned lens structure data and lens performance parameters. Each point diagram represents the size of the blur spot on the image plane across the entire field of view at different temperatures, providing a visual understanding of the optical performance. From Figure 2 As can be seen, within the surface temperature range of 0-28.4°C, the root mean square (RMS) value of the full-field-of-view speckle of the optical imaging system is less than 1 μm, indicating that the speckle size is effectively controlled by temperature differences. The optical imaging system exhibits high imaging quality.

[0107] As attached Figure 3 This is an axial aberration curve diagram for an optical imaging system with the aforementioned lens structure data and lens performance parameters, used to represent the axial aberration of the optical imaging lens. The horizontal axis represents axial aberration, and the vertical axis represents the normalized field of view. Figure 3As can be seen, the axial aberration of the optical imaging system is controlled within the range of 0.09mm, resulting in high imaging quality.

[0108] As attached Figure 4 The figure shown is a field curvature / distortion curve of an optical imaging system with the above lens structure data and lens performance parameters, used to represent the field curvature and distortion of the optical imaging system within the temperature range.

[0109] lie in Figure 4 In the field curvature curve diagram on the left, the horizontal axis represents the field curvature value and the vertical axis represents the surface temperature. It can be seen from the figure that the field curvature value is less than 0.09 mm in the temperature range of 0-28.4°.

[0110] lie in Figure 4 In the distortion curve graph on the right, the horizontal axis represents the percentage of distortion, and the vertical axis represents the surface temperature. It can be seen from the graph that the percentage of distortion is less than 4% in the temperature range of 0-28.4°.

[0111] Therefore, in this embodiment, the field curvature and distortion of the optical imaging system are well controlled, and the optical imaging system has high imaging quality.

[0112] As attached Figure 5 The image shown is a stray light analysis diagram of the binary plane in an optical imaging system with the aforementioned lens structure data and lens performance parameters. From... Figure 5 As can be seen, by optimizing the binary surface structure and parameters, the optical imaging system overcomes the serious stray light problem that is common in binary surfaces.

[0113] As attached Figure 6 The diagram shows the geometrical entry energy at an ambient temperature of 25°C for an optical imaging system with the aforementioned lens structure data and performance parameters. It represents the spot size at 80% entry energy for each field of view and wavelength of light in the optical imaging system. Similar to the dot plot, at 80% entry energy, a smaller spot size indicates better image quality. (See attached diagram.) Figure 6 It can be seen that the speckle of the incident light of each wavelength in the optical imaging system is less than 44μm when the incident energy is 80%, so the optical imaging system has high imaging quality at 25°.

[0114] As attached Figure 7 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of -100°C. (The last sentence appears to be incomplete and possibly refers to a different image.) Figure 7 It is known that the speckle of the incident light of each wavelength in the optical imaging system is less than 42μm when the incident energy is 80%, so the optical imaging system has high imaging quality at -100℃.

[0115] As attached Figure 8 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of -60°C. (The image is then displayed with the appendix...) Figure 8 It is known that the speckle of the incident light of each wavelength in the optical imaging system is less than 43μm when the incident energy is 80%, so the optical imaging system has high imaging quality at -60℃.

[0116] As attached Figure 9 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of -20°C. (The last sentence appears to be incomplete and possibly refers to a different image.) Figure 9 It is known that the speckle of the incident light of each wavelength in the optical imaging system is less than 43μm when the incident energy is 80%, so the optical imaging system has high imaging quality at -20℃.

[0117] As attached Figure 10 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of 20°C. (The last sentence appears to be incomplete and possibly refers to a different image.) Figure 10 It can be seen that the speckle of the incident light of each wavelength in the optical imaging system is less than 43μm when the incident energy is 80%, so the optical imaging system has high imaging quality at 20℃.

[0118] As attached Figure 11 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of 60°C. (The last sentence appears to be incomplete and possibly refers to a different image.) Figure 11 It is known that the speckle of incident light of each wavelength in the optical imaging system is less than 45μm when the incident energy is 80%, therefore the optical imaging system has high imaging quality at 60℃.

[0119] As attached Figure 12 The image shown is the geometrical ingress energy diagram of an optical imaging system with the aforementioned lens structure data and lens performance parameters at an ambient temperature of 100°C. (The last sentence appears to be incomplete and possibly refers to a different image.) Figure 12 It is known that the speckle of incident light of each wavelength in the optical imaging system is less than 45μm when the incident energy is 80%, therefore the optical imaging system has high imaging quality at 100℃.

[0120] Therefore, with the optical imaging system provided in this application, when the vehicle-mounted lidar receiving lens is in an environment with a temperature range of ±100℃, the diffuse spot of each wavelength of incident light in the optical imaging system is less than 45μm when the incident energy is 80%. It can be considered that the optical imaging system provided in this embodiment can remain in focus in an environment of ±100℃.

[0121] Test results show that the optical imaging system provided in this embodiment has an imaging circle diameter D=12mm, a field of view (FOV) of 56.8°, a focal length (f) of 12.7mm, an aperture of 0.95, an ultra-large relative aperture, a total optical length (TTL) of <47mm, can remain in focus in an environment of ±100℃, and has weak stray light intensity.

[0122] The optical imaging system provided in this embodiment has a large relative aperture and can adapt to environments with large temperature differences, thereby achieving the technical effect of comprehensively and reliably acquiring environmental information under complex driving conditions and improving driving safety.

[0123] Example 2

[0124] This application also discloses a camera module. Figure 13 A schematic diagram of the camera module according to Embodiment 2 of the present invention is shown. The camera module 200 includes an image sensor 201 and an optical lens 100 as described in Embodiment 1 above. The image sensor 201 is disposed on the image side of the optical lens 100. The optical lens 100 can be used to receive the light signal of the subject and project it onto the image sensor 201. The image sensor 201 can be used to convert the light signal corresponding to the subject into an image signal. Further details are omitted here. It is understood that the camera module 200 with the aforementioned optical lens 100 can improve the imaging quality of the lens module while meeting the requirements for simplified and thinner lens module design. Since the above technical effects have been described in detail in the embodiments of the optical lens 100, they will not be repeated here.

[0125] Example 3

[0126] This application also discloses an electronic device, Figure 14 A schematic diagram of the electronic device according to Embodiment 3 of the present invention is shown. The electronic device 300 includes a housing 300 and a camera module 200 as described above. The camera module 200 is disposed on the housing 301 to acquire image information. The electronic device 300 may be, but is not limited to, a mobile phone, tablet computer, laptop computer, smartwatch, monitor, etc. It is understood that the electronic device 300 having the aforementioned camera module 200 also possesses all the technical effects of the aforementioned optical lens 100. That is, the electronic device 300 can improve the imaging quality of the lens module while meeting the requirements for simplified and thinner lens module design. Since the above technical effects have been described in detail in the embodiments of the optical lens 100, they will not be repeated here.

[0127] The above descriptions are merely embodiments of this application. Commonly known structures and characteristics of the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this application. These should also be considered within the scope of protection of this application, and will not affect the effectiveness of the implementation of this application or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An optical imaging system applied to a vehicle-mounted lidar receiving lens, characterized in that, The optical imaging system includes: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the optical axis from the object side to the image side; wherein, the optical imaging system has 6 lenses with refractive power; The first lens has negative refractive power, and the object-side surface of the first lens is convex. The second lens has positive refractive power; The third lens has negative refractive power, and the object-side surface of the third lens is convex. The fourth lens has positive refractive power; The fifth lens has positive refractive power; The sixth lens has positive refractive power, and the object-side surface of the sixth lens is a binary surface; The optical imaging system satisfies the following relationship: TanFOV / Fno>0.25; Wherein, FOV is the field of view of the optical imaging system; Fno is the aperture of the optical imaging system; The optical imaging system satisfies the following relationship: 1 / (f1 / 1000)+1 / (f2 / 1000)+1 / (f3 / 1000)+1 / (f4 / 1000)> 1 / (f5 / 1000)+1 / (f6 / 1000); 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; f5 is the focal length of the fifth lens; and f6 is the focal length of the sixth lens.

2. The optical imaging system as described in claim 1, characterized in that, The optical imaging system satisfies the following relationship: |EA2-EA4|≤90; Wherein, EA2 is the second-order binary surface coefficient of the binary surface; EA4 is the fourth-order binary surface coefficient of the binary surface.

3. The optical imaging system as described in claim 1, characterized in that, An aperture stop is provided between the third lens and the fourth lens.

4. The optical imaging system as described in claim 1, characterized in that, The optical imaging system satisfies the following relationship: f1<0, f2>0, f3<0, f4>0; 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; and f4 is the focal length of the fourth lens.

5. An optical imaging system as described in claim 1, characterized in that, The optical imaging system satisfies the following relationship: |G6R1|>15; Wherein, G6R1 is the radius of curvature of the object-side surface of the sixth lens.

6. An optical imaging system as described in claim 1, characterized in that, The optical imaging system satisfies the following relationship: 1.5*(CT4+CT5) <CT6<2.5*(CT4+CT5); Wherein, CT4 is the lens thickness of the fourth lens; CT5 is the lens thickness of the fifth lens; and CT6 is the lens thickness of the sixth lens.

7. An optical imaging system as described in claim 1, characterized in that, The optical imaging system satisfies the following relationship: N2>1.85； Where N2 is the refractive index of the second lens.

8. A camera module, characterized in that: The camera module includes an image sensor and an optical imaging system as described in any one of claims 1-7, wherein the image sensor is disposed on the image side of the optical imaging system.

9. An electronic device, characterized in that, The electronic device includes a housing and a camera module as described in claim 8, wherein the camera module is disposed within the housing.

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