Vehicle-mounted projection lens and vehicle

Abstract

The invention relates to a vehicle-mounted projection lens and a vehicle, and the projection lens comprises a first lens which has negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a third lens element with positive refractive power having a convex object-side surface and a convex image-side surface; a fourth lens element with positive refractive power having a concave object-side surface and a convex image-side surface; the fifth lens element with negative refractive power has a concave object-side surface and a concave image-side surface. A sixth lens element with positive refractive power having a convex object-side surface and a convex image-side surface; the third lens is a spherical lens; the vehicle-mounted projection lens satisfies the following conditions: 300 lt; dlt; 3500, 3500. The vehicle-mounted projection lens and the vehicle obtained by the invention have the following advantages: the vehicle-mounted projection lens is not influenced by temperature change, an image can be kept clear and basically free of chromatic aberration when being lightened, the field angle is large, six lenses are adopted, the number of the lenses is small, the structure is compact, and the assembly is more convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of optical imaging, and in particular to a vehicle-mounted projection lens and a vehicle. Background Art

[0002] Conventional car welcome carpet lights are typically installed at an angle, typically above 70°, on vehicle door sills, undercarriages, and sliding doors. This creates a longer image and reduces clarity. Furthermore, most module lenses are injection-molded, which can expand and contract at ambient temperatures (-40°C to 80°C), causing deformation and blurring of the image, impacting the driver's and passengers' visual experience. This is especially true for wide-area (60° or greater) welcome carpet lights, where the image width is greater and blurring is more severe. Summary of the Invention

[0003] An object of the present application is to provide a vehicle-mounted projection lens and a vehicle, with clear patterns and high brightness and a small module size.

[0004] The technical solution adopted in the present application is: a vehicle-mounted projection lens, which includes, in order from the object side to the image side along the optical axis: a first lens, a second lens, an aperture, a third lens, a fourth lens, a fifth lens, and a sixth lens; The first lens has negative refractive power, its object side surface is convex, and its image side surface is concave; The second lens has positive refractive power, its object side surface is concave, and its image side surface is convex; The third lens has positive refractive power, and its object-side surface is convex, and its image-side surface is convex; The fourth lens has positive refractive power, its object side surface is concave, and its image side surface is convex; The fifth lens element has negative refractive power, and its object-side surface and image-side surface are concave; The sixth lens has positive refractive power, and its object-side surface is convex, and its image-side surface is convex; The third lens is a spherical lens; The first lens, the second lens, the fourth lens, the fifth lens and the sixth lens are all aspherical lenses; The vehicle-mounted projection lens meets the following conditions: 300 <D<3500。

[0005] In some embodiments of the present application, there is a gap between any two adjacent lenses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens.

[0006] In some embodiments of the present application, the refractive index of at least one of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens satisfies: 1.45 <Nd<1.7。

[0007] In some embodiments of the present application, the third lens is made of glass.

[0008] In some embodiments of the present application, a distance T14 between the sixth lens and the image plane on the optical axis satisfies: T14>1.

[0009] In some embodiments of the present application, the maximum field of view angle FOV of the vehicle-mounted projection lens satisfies: 50 <FOV<120。

[0010] In some embodiments of the present application, the vehicle-mounted projection lens satisfies: ImgH≥1.3, where ImgH is half of the diagonal length of the effective pixel area on the imaging surface.

[0011] Furthermore, the refractive indexes of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens all satisfy: 1.45 <Nd<1.7。

[0012] The vehicle-mounted projection lens obtained by the present invention has the following advantages: 1. It is not affected by temperature changes and can keep the image clear and basically free of color difference when it is lit; 2. It has a large field of view angle of up to 80 degrees or more, and the image size is larger, allowing customers to achieve an immersive experience; 3. It uses five injection-molded optical lenses and one glass lens, with a small number of lenses, a compact structure, and more convenient assembly.

[0013] A vehicle comprises the above-mentioned vehicle-mounted projection lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a structural diagram of embodiment 1 of the present invention; Figure 2 1 is a graph showing astigmatism and distortion curves of Example 1 of the present invention; Figure 3 is a color difference curve diagram of Example 1 of the present invention under normal temperature conditions; Figure 4 is a color difference curve diagram of Example 1 of the present invention at 80°C; Figure 5 is a color difference curve diagram of Example 1 of the present invention at -40°C; Figure 6 : is a through-focus MTF curve diagram of Example 1 of the present invention under normal temperature conditions; Figure 7 80° C. is a defocus MTF curve of Example 1 of the present invention; Figure 8 1 is a through-focus MTF curve at -40°C of Example 1 of the present invention; Figure 9 is a schematic structural diagram of embodiment 2 of the present invention; Figure 10 1 is a graph showing astigmatism and distortion curves of Example 2 of the present invention; Figure 11 is a color difference curve diagram of Example 2 of the present invention under normal temperature conditions; Figure 12 is a color difference curve diagram of Example 2 of the present invention at 80°C; Figure 13 is a color difference curve diagram of Example 2 of the present invention at -40°C; Figure 14 : is a through-focus MTF curve diagram of Example 2 of the present invention under normal temperature conditions; Figure 15 2 is a through-focus MTF curve at 80° C. of Example 2 of the present invention; Figure 16 2 is a through-focus MTF curve at -40°C of Example 2 of the present invention; Figure 17 is a schematic structural diagram of embodiment 3 of the present invention; Figure 18 1 is a graph showing astigmatism and distortion curves of Example 3 of the present invention; Figure 19 is a color difference curve diagram of Example 3 of the present invention under normal temperature conditions; Figure 20 is a color difference curve diagram of Example 3 of the present invention at 80°C; Figure 21 is a color difference curve diagram of Example 3 of the present invention at -40°C; Figure 22 3 is a through-focus MTF curve diagram under normal temperature conditions of Example 3 of the present invention; Figure 23 3 is a through-focus MTF curve at 80° C. of Example 3 of the present invention; Figure 24 3 is a through-focus MTF curve at -40°C of Example 3 of the present invention; Figure 25 This is the defocus MTF curve of a conventional optical lens at 80°C. DETAILED DESCRIPTION

[0015] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure is described in detail, clearly, and completely in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present disclosure and are not intended to limit the present disclosure.

[0016] In the description of this application, if there is a description of first or second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0017] Those skilled in the art should understand that, in the disclosure of this application, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, which are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms cannot be understood as limiting this application.

[0018] The vehicle-mounted projection lens according to an exemplary embodiment of the present application may include, for example, six lenses having optical power, namely, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, and a sixth lens 6. These six lenses are arranged in sequence from the object side to the image side along the optical axis.

[0019] The first lens 1 has negative refractive power, its object side surface is convex, and its image side surface is concave, and can be made of plastic; The second lens 2 has positive refractive power, its object side surface is concave, and its image side surface is convex, and can be made of plastic; The third lens 3 has positive refractive power, its object-side surface is convex, its image-side surface is convex, and it can be made of glass; The fourth lens element 4 has positive refractive power, has a concave object-side surface and a convex image-side surface, and can be made of plastic. The fifth lens element 5 has negative refractive power, has a concave object-side surface and a concave image-side surface, and can be made of plastic. The sixth lens 6 has positive refractive power, has a convex object-side surface and a convex image-side surface, and can be made of plastic. The third lens 3 is a spherical lens; The first lens 1, the second lens 2, the fourth lens 4, the fifth lens 5 and the sixth lens 6 are all aspherical lenses; The vehicle-mounted projection lens meets the following conditions: 300 <D<3500。

[0020] It is not affected by temperature changes and can keep the image clear at all times. It has basically no chromatic aberration and a large field of view. It uses six lenses with a small number of lenses, a compact structure, and is easier to assemble.

[0021] A diaphragm 7 is provided in front of the third lens 3 for limiting the light beam.

[0022] In an exemplary embodiment, there is a gap between any two adjacent lenses among the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6. The gap can reduce heat transfer, resulting in a small temperature influence and good heat insulation effect, ensuring that when the temperature changes, the resolution does not change significantly, and the chromatic aberration does not increase either, that is, there will be no phenomenon of color fringes after the temperature rises. It is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0023] In an exemplary embodiment, the refractive index of at least one lens among the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6 satisfies: 1.45 < Nd < 1.7. When the refractive index of at least one lens satisfies the range of 1.45 < Nd < 1.7, the vehicle-mounted projection lens can further ensure that the image remains clear when the temperature changes, and is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0024] In an exemplary embodiment, the third lens 3 is made of glass, with a small temperature influence and good heat insulation effect.

[0025] In an exemplary embodiment, the distance T14 between the sixth lens 6 and the image plane on the optical axis satisfies: T14 > 1. When the range of T14 > 1 is satisfied, the vehicle-mounted projection lens can further ensure that the image remains clear when the temperature changes, and is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0026] In an exemplary embodiment, the maximum field angle FOV of the vehicle-mounted projection lens satisfies: 50 < FOV < 120. When the range of 50 < FOV < 120 is satisfied, the vehicle-mounted projection lens can further ensure that the image remains clear when the temperature changes, and is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0027] In an exemplary embodiment, the vehicle-mounted projection lens satisfies: ImgH ≥ 1.3, where ImgH is half of the diagonal length of the effective pixel region on the imaging plane. When the range of ImgH ≥ 1.3 is satisfied, the vehicle-mounted projection lens can further ensure that the image remains clear when the temperature changes, and is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0028] In an exemplary embodiment, the refractive indices of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6 all satisfy: 1.45 < Nd < 1.7. When the refractive indices of all lenses satisfy the range of 1.45 < Nd < 1.7, the vehicle-mounted projection lens can further ensure that the image remains clear when the temperature changes, and is applicable to normal temperature environments, high temperature environments, and low temperature environments at the same time.

[0029] The object side surface of the lens described in the present invention is a convex surface, which means that when a section is made through any point on the object side surface of the lens, the surface is always on the right side of the section surface, and its radius of curvature is positive; otherwise, the object side surface is a concave surface, and its radius of curvature is negative; the image side surface is a convex surface, which means that when a section is made through any point on the image side surface of the lens, the surface is always on the left side of the section surface, and its radius of curvature is negative; otherwise, the image side surface is a concave surface, and its radius of curvature is positive; if a section is made through any point on the object side or the image side surface of the lens, the surface has both parts on the left and parts on the right side of the section surface, then there is an inflection point of the curve on the surface, and the above judgment of the convexity and concavity of the object side and image side surfaces near the optical axis still applies.

[0030] Example 1: This embodiment provides a vehicle-mounted projection lens, such as Figure 1 As shown, along the optical axis, from the object side to the image side, it includes: a first lens 1, a second lens 2, an aperture 7, a third lens 3, a fourth lens 4, a fifth lens 5 and a sixth lens 6; The first lens 1 has negative refractive power, the object-side surface S1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; The second lens 2 has positive refractive power, the object-side surface S3 is concave near the optical axis, and the image-side surface S4 is convex near the optical axis; The third lens element 3 has positive refractive power, and its object-side surface S6 is convex near the optical axis, and its image-side surface S7 is convex near the optical axis; The fourth lens element 4 has positive refractive power, an object-side surface S8 thereof is concave near the optical axis, and an image-side surface S9 thereof is convex near the optical axis; The fifth lens element 5 has negative refractive power, and its object-side surface S10 is concave near the optical axis, and its image-side surface S11 is concave near the optical axis; The sixth lens element 6 has positive refractive power, an object-side surface S12 thereof is convex near the optical axis, and an image-side surface S13 thereof is convex near the optical axis; The distance D between the projected object and the vehicle-mounted projection lens is 300mm. Light from the object sequentially passes through surfaces S1 to S13 and is ultimately imaged on the imaging surface IMA. In actual use, this embodiment projects light from the image side outward, projecting a pattern onto the object side. Specifically, the pattern to be projected is placed on the image side and projected outward onto the vehicle's carpet or floor. The projection distance of 300mm does not necessarily require a 300mm distance; any distance within 300mm can be proportionally placed, allowing the pattern to be projected proportionally onto the vehicle's carpet or floor. Of course, this vehicle-mounted projection lens can also be applied to other projection surfaces, such as walls, such as conference room projection lamps, home projection lamps, and security lenses.

[0031] The detailed parameters are shown in Table 1 below, where the units of curvature radius R and thickness T are both in millimeters; Table 1

[0032] The first lens element 1 is an aspherical lens, with both its object-side surface S1 and image-side surface S2 being aspherical. The second lens element 2 is an aspherical lens, with both its object-side surface S3 and image-side surface S4 being aspherical. The fourth lens element 4 is an aspherical lens, with both its object-side surface S8 and image-side surface S9 being aspherical. The fifth lens element 5 is an aspherical lens, with both its object-side surface S10 and image-side surface S11 being aspherical. The sixth lens element 6 is an aspherical lens, with both its object-side surface S12 and image-side surface S13 being aspherical.

[0033] The conic coefficient k and the high-order coefficients A4, A6 and A8 of the aspheric lens surfaces S1, S2, S3, S4, S8, S9, S10, S11, S12 and S13 are shown in Table 2 below: Table 2

[0034] Table 3 below shows the relationship between the entire focal length f of the vehicle-mounted projection lens, the distance T14 between the sixth lens element 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle-mounted projection lens), the total optical length TTL of the vehicle-mounted projection lens and the entire focal length f of the vehicle-mounted projection lens, and the relationship between the distance T14 between the sixth lens element 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle-mounted projection lens) and the total optical length TTL of the vehicle-mounted projection lens in a specific embodiment.

[0035] Table 3

[0036] See Figure 2 , Figure 2 This graph shows the astigmatism and distortion curves for automotive projection lenses in the visible light band. Astigmatism occurs when the luminous object is not on the optical axis of the optical system. The light beam emitted by the object is tilted at an angle to the optical axis. After refraction through the lens, the convergence points of the meridional and sagittal beamlets are not aligned. This means the beams cannot be focused, resulting in unclear images and astigmatism. Distortion refers to the deformation between the actual and ideal image planes when an object is imaged through a lens.

[0037] See Figure 3 , Figure 3 This graph shows the chromatic aberration curve for the visible light band of an automotive projection lens at room temperature (20°C-25°C). Chromatic aberration, referring to color aberration, is a serious defect in lens systems when imaging. Because the same material has different refractive indices for different wavelengths of light, this causes multi-wavelength beams to propagate in separate directions after passing through the lens, a phenomenon known as dispersion.

[0038] See Figure 4 , Figure 4This is the chromatic aberration curve of the visible light band of the car projection lens under high temperature conditions of 80℃.

[0039] See Figure 5 , Figure 5 This is the chromatic aberration curve of the visible light band of the car projection lens at a low temperature of -40℃.

[0040] See Figure 6 , Figure 6 This is a through-focus MTF curve for an automotive projection lens at room temperature (20°C-25°C). MTF, or Modulation Transfer Function, is a relatively scientific method for analyzing lens resolution.

[0041] See Figure 7 , Figure 7 This is the through-focus MTF curve of the automotive projection lens at a high temperature of 80°C.

[0042] See Figure 8 , Figure 8 This is the through-focus MTF curve of the automotive projection lens at a low temperature of -40°C.

[0043] At the same spatial frequency (100 lp / mm for both the present embodiment and the control group), compared with the defocus MTF curve of the existing optical lens at a high temperature of 80°C (such as Figure 25 ), the defocus MTF curve of the lens of this embodiment under high temperature conditions of 80°C (such as Figure 7 ) The defocus is very small, within 0.01mm, the MTF is high, and the chromatic aberration is also very small (such as Figure 4 ). At the same time, the defocus MTF curve of the lens of this embodiment at room temperature (such as Figure 6 ) and color difference (such as Figure 3 ) and the defocus MTF curve at low temperature (such as Figure 8 ) and color difference (such as Figure 5 ) is also very small; that is, in normal temperature, high temperature and low temperature environments (-40℃~80℃), this car projection lens can maintain small defocus, high MTF and small chromatic aberration.

[0044] Example 2: This embodiment provides a vehicle-mounted projection lens, such as Figure 9 As shown, along the optical axis, from the object side to the image side, it includes: a first lens 1, a second lens 2, an aperture 7, a third lens 3, a fourth lens 4, a fifth lens 5 and a sixth lens 6; The first lens 1 has negative refractive power, the object-side surface S1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; The second lens 2 has positive refractive power, the object-side surface S3 is concave near the optical axis, and the image-side surface S4 is convex near the optical axis; The third lens element 3 has positive refractive power, and its object-side surface S6 is convex near the optical axis, and its image-side surface S7 is convex near the optical axis; The fourth lens element 4 has positive refractive power, an object-side surface S8 thereof is concave near the optical axis, and an image-side surface S9 thereof is convex near the optical axis; The fifth lens element 5 has negative refractive power, and its object-side surface S10 is concave near the optical axis, and its image-side surface S11 is concave near the optical axis; The sixth lens element 6 has positive refractive power, an object-side surface S12 thereof is convex near the optical axis, and an image-side surface S13 thereof is convex near the optical axis; The distance D between the projected object and the vehicle-mounted projection lens is 3500mm. Light from the object sequentially passes through surfaces S1 to S13 and is ultimately imaged on the imaging surface IMA. In actual use, this embodiment projects light outward from the image side, projecting a pattern onto the object side. Specifically, the pattern to be projected is placed on the image side and projected outward onto the vehicle's carpet or floor. The projection distance of 3500mm does not necessarily require a distance of 3500mm; any distance within 3500mm can be proportionally placed, allowing the pattern to be projected proportionally onto the vehicle's carpet or floor. Of course, this vehicle-mounted projection lens can also be applied to other projection surfaces, such as walls, such as conference room projection lamps, home projection lamps, and security lenses.

[0045] The detailed parameters are shown in Table 4 below, where the units of curvature radius R and thickness T are both millimeters; Table 4

[0046] The first lens element 1 is an aspherical lens, with both its object-side surface S1 and image-side surface S2 being aspherical. The second lens element 2 is an aspherical lens, with both its object-side surface S3 and image-side surface S4 being aspherical. The fourth lens element 4 is an aspherical lens, with both its object-side surface S8 and image-side surface S9 being aspherical. The fifth lens element 5 is an aspherical lens, with both its object-side surface S10 and image-side surface S11 being aspherical. The sixth lens element 6 is an aspherical lens, with both its object-side surface S12 and image-side surface S13 being aspherical.

[0047] The conic coefficient k and the high-order coefficients A4, A6 and A8 of the aspheric lens surfaces S1, S2, S3, S4, S8, S9, S10, S11, S12 and S13 are shown in Table 5 below: Table 5

[0048] Table 6 below shows the relationship between the entire group focal length f of the vehicle projection lens, the distance T14 between the sixth lens 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle projection lens), the total optical length TTL of the vehicle projection lens and the entire group focal length f of the vehicle projection lens, and the relationship between the distance T14 between the sixth lens 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle projection lens) and the total optical length TTL of the vehicle projection lens in a specific embodiment.

[0049] Table 6

[0050] See Figure 10 , Figure 10 It is the astigmatism and distortion curve of the vehicle-mounted projection lens in the visible light band.

[0051] See Figure 11 , Figure 11 This is the color difference curve of the visible light band of the car projection lens under normal temperature conditions (20℃-25℃).

[0052] See Figure 12 , Figure 12 This is the chromatic aberration curve of the visible light band of the car projection lens under high temperature conditions of 80℃.

[0053] See Figure 13 , Figure 13 This is the chromatic aberration curve of the visible light band of the car projection lens at a low temperature of -40℃.

[0054] See Figure 14 , Figure 14 This is the through-focus MTF curve of the automotive projection lens under normal temperature conditions (20℃-25℃).

[0055] See Figure 15 , Figure 15 This is the through-focus MTF curve of the automotive projection lens at a high temperature of 80°C.

[0056] See Figure 16 , Figure 16 This is the through-focus MTF curve of the automotive projection lens at a low temperature of -40°C.

[0057] At the same spatial frequency (100 lp / mm for both the present embodiment and the control group), compared with the defocus MTF curve of the existing optical lens at a high temperature of 80°C (such as Figure 25 ), the defocus MTF curve of the lens of this embodiment under high temperature conditions of 80°C (such as Figure 15 ) The defocus is very small, within 0.01mm, the MTF is high, and the chromatic aberration is also very small (such as Figure 12 ). At the same time, the defocus MTF curve of the lens of this embodiment at room temperature (such as Figure 14 ) and color difference (such as Figure 11 ) and the defocus MTF curve at low temperature (such as Figure 16 ) and color difference (such as Figure 13 ) is also very small; that is, in normal temperature, high temperature and low temperature environments (-40℃~80℃), this car projection lens can maintain small defocus, high MTF and small chromatic aberration.

[0058] Example 3: This embodiment provides a vehicle-mounted projection lens, such as Figure 17 As shown, along the optical axis, from the object side to the image side, it includes: a first lens 1, a second lens 2, an aperture 7, a third lens 3, a fourth lens 4, a fifth lens 5 and a sixth lens 6; The first lens 1 has negative refractive power, the object-side surface S1 is convex near the optical axis, and the image-side surface S2 is concave near the optical axis; The second lens 2 has positive refractive power, the object-side surface S3 is concave near the optical axis, and the image-side surface S4 is convex near the optical axis; The third lens element 3 has positive refractive power, and its object-side surface S6 is convex near the optical axis, and its image-side surface S7 is convex near the optical axis; The fourth lens element 4 has positive refractive power, an object-side surface S8 thereof is concave near the optical axis, and an image-side surface S9 thereof is convex near the optical axis; The fifth lens element 5 has negative refractive power, and its object-side surface S10 is concave near the optical axis, and its image-side surface S11 is concave near the optical axis; The sixth lens element 6 has positive refractive power, an object-side surface S12 thereof is convex near the optical axis, and an image-side surface S13 thereof is convex near the optical axis; The distance D between the projected object and the vehicle-mounted projection lens is 2000mm. Light from the object sequentially passes through surfaces S1 to S13 and is ultimately imaged on the imaging surface IMA. In actual use, this embodiment projects light outward from the image side, projecting a pattern onto the object side. Specifically, the pattern to be projected is placed on the image side and projected outward onto the vehicle's carpet or floor. The projection distance of 2000mm does not necessarily require a distance of 2000mm; any distance within 2000mm can be proportionally placed, allowing the pattern to be projected proportionally onto the vehicle's carpet or floor. Of course, this vehicle-mounted projection lens can also be applied to other projection surfaces, such as walls, such as conference room projection lamps, home projection lamps, and security lenses.

[0059] The detailed parameters are shown in Table 7 below, where the units of curvature radius R and thickness T are both in millimeters; Table 7

[0060] The first lens element 1 is an aspherical lens, with both its object-side surface S1 and image-side surface S2 being aspherical. The second lens element 2 is an aspherical lens, with both its object-side surface S3 and image-side surface S4 being aspherical. The fourth lens element 4 is an aspherical lens, with both its object-side surface S8 and image-side surface S9 being aspherical. The fifth lens element 5 is an aspherical lens, with both its object-side surface S10 and image-side surface S11 being aspherical. The sixth lens element 6 is an aspherical lens, with both its object-side surface S12 and image-side surface S13 being aspherical.

[0061] The conic coefficient k and the higher-order coefficients A4, A6 and A8 of the aspheric lens surfaces S1, S2, S3, S4, S8, S9, S10, S11, S12 and S13 are shown in Table 8 below: Table 8

[0062] Table 9 below shows the relationship between the entire group focal length f of the vehicle projection lens, the distance T14 between the sixth lens 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle projection lens), the total optical length TTL of the vehicle projection lens and the entire group focal length f of the vehicle projection lens, and the relationship between the distance T14 between the sixth lens 6 and the image plane IMA on the optical axis (the optical back focus BFL of the vehicle projection lens) and the total optical length TTL of the vehicle projection lens in a specific embodiment.

[0063] Table 9

[0064] See Figure 18 , Figure 18 It is the astigmatism and distortion curve of the vehicle-mounted projection lens in the visible light band.

[0065] See Figure 19 , Figure 19 This is the color difference curve of the visible light band of the car projection lens under normal temperature conditions (20℃-25℃).

[0066] See Figure 20 , Figure 20 This is the chromatic aberration curve of the visible light band of the car projection lens under high temperature conditions of 80℃.

[0067] See Figure 21 , Figure 21 This is the chromatic aberration curve of the visible light band of the car projection lens at a low temperature of -40℃.

[0068] See Figure 22 , Figure 22 This is the through-focus MTF curve of the automotive projection lens under normal temperature conditions (20℃-25℃).

[0069] See Figure 23 , Figure 23This is the through-focus MTF curve of the automotive projection lens at a high temperature of 80°C.

[0070] See Figure 24 , Figure 24 This is the through-focus MTF curve of the automotive projection lens at a low temperature of -40°C.

[0071] At the same spatial frequency (100 lp / mm for both the present embodiment and the control group), compared with the defocus MTF curve of the existing optical lens at a high temperature of 80°C (such as Figure 25 ), the defocus MTF curve of the lens of this embodiment under high temperature conditions of 80°C (such as Figure 23 ) The defocus is very small, within 0.01mm, the MTF is high, and the chromatic aberration is also very small (such as Figure 20 ). At the same time, the defocus MTF curve of the lens of this embodiment at room temperature (such as Figure 22 ) and color difference (such as Figure 19 ) and the defocus MTF curve at low temperature (such as Figure 24 ) and color difference (such as Figure 21 ) is also very small; that is, in normal temperature, high temperature and low temperature environments (-40℃~80℃), this car projection lens can maintain small defocus, high MTF and small chromatic aberration.

[0072] Example 4: This embodiment provides a vehicle, including a vehicle-mounted projection lens as described in embodiment 1, embodiment 2, or embodiment 3.

[0073] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A vehicle-mounted projection lens, characterized in that: The lens comprises, in order from the object side to the image side along the optical axis: a first lens (1), a second lens (2), an aperture (7), a third lens (3), a fourth lens (4), a fifth lens (5), and a sixth lens (6); The first lens (1) has negative refractive power, and its object side surface is convex and its image side surface is concave; The second lens (2) has positive refractive power, its object side surface is concave, and its image side surface is convex; The third lens (3) has positive refractive power, and its object side surface is convex, and its image side surface is convex; The fourth lens (4) has positive refractive power, its object side surface is concave, and its image side surface is convex; The fifth lens (5) has negative refractive power, and its object side surface is concave, and its image side surface is concave; The sixth lens (6) has positive refractive power, and its object side surface is convex, and its image side surface is convex; The third lens (3) is a spherical lens; The first lens (1), the second lens (2), the fourth lens (4), the fifth lens (5) and the sixth lens (6) are all aspherical lenses; The vehicle-mounted projection lens meets the following conditions: 300 <D<3500。 2. The vehicle-mounted projection lens according to claim 1, characterized in that: There is a gap between any two adjacent lenses of the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5) and the sixth lens (6).

3. The vehicle-mounted projection lens according to claim 1, characterized in that: The refractive index of at least one of the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5) and the sixth lens (6) satisfies: 1.45 <Nd<1.7。 4. The vehicle-mounted projection lens according to claim 1, wherein: The third lens (3) is made of glass.

5. The vehicle-mounted projection lens according to claim 1, characterized in that: The distance T14 between the sixth lens (6) and the image plane on the optical axis satisfies: T14>1.

6. The vehicle-mounted projection lens according to claim 1, characterized in that: The maximum field of view angle FOV of the vehicle-mounted projection lens meets the following requirements: 50 <FOV<120。 7. The vehicle-mounted projection lens according to claim 1, characterized in that: The vehicle-mounted projection lens satisfies: ImgH≥1.3, where ImgH is half of the diagonal length of the effective pixel area on the imaging surface.

8. The vehicle-mounted projection lens according to claim 3, characterized in that: The refractive indices of the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5) and the sixth lens (6) all satisfy: 1.45 <Nd<1.7。 9. A vehicle, characterized in that: The invention comprises a vehicle-mounted projection lens according to any one of claims 1 to 8.

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