Long-focus receiving lens and laser radar

Abstract

The embodiment of the utility model discloses a long-focus receiving lens and a laser radar, in the long-focus receiving lens provided by the embodiment of the invention, a first lens and a second lens have positive focal power and adopt convex-concave surface types, a third lens has positive focal power and adopts a biconvex surface type, a fourth lens has negative focal power and adopts a biconcave surface type, and a fifth lens has positive focal power and adopts a biconvex surface type. The fifth lens has negative focal power and adopts a concave-convex surface type, and the sixth lens has negative focal power and adopts a double-concave surface type. According to the technical scheme, the shapes of the mirror surfaces of the lenses of the telephoto receiving lens are reasonably matched, so that the lens has a shorter optical total length, the size of the receiving lens is effectively controlled, and the telephoto receiving lens can adapt to a larger image surface size through setting the shapes of the mirror surfaces of the lenses, so that the image quality of the telephoto receiving lens is improved. High resolution and low distortion are achieved, and the imaging effect is not affected by shortening the total optical length.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of vehicle radar technology, and in particular to a telephoto receiving lens and a laser radar. Background Art

[0002] In advanced driver assistance, the application of LiDAR is becoming more and more common. LiDAR calculates the distance between the target and the vehicle by emitting and receiving laser beams and calculating the flight time, thereby calculating the distance between the target and the vehicle, and realizing the recognition and detection of the target. Compared with the detection characteristics of solid-state blind spot radar with a large field of view at a short distance, forward LiDAR usually requires a longer detection distance and higher angular resolution, so it needs to be matched with a telephoto lens to achieve high resolution. At the same time, for the beauty of the vehicle, the volume of the forward LiDAR is limited. For forward radars that realize the field of view angle through a one-dimensional or two-dimensional mechanical scanning module, in order to reserve space for the scanning module, the lens size requirements are more stringent. At present, for the existing telephoto lens, the mechanical size is too large to be used in the transmitting module of the LiDAR, and the glued parts contained in the ordinary lens cannot meet the vehicle regulations of the vehicle-mounted LiDAR. In addition, with the development of chip processing technology, the chip integration has increased and the size has increased, making it possible to have a LiDAR with higher resolution, but at the same time, it has also further increased the design difficulty of the telephoto lens. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art or related technology.

[0004] To this end, a first aspect of the present invention provides a telephoto receiving lens.

[0005] A second aspect of the utility model provides a laser radar.

[0006] In view of this, according to a first aspect of an embodiment of the present application, a telephoto receiving lens is provided, comprising: a first lens, the first lens having positive optical power, a first side surface of the first lens being a convex surface, and a second side surface of the first lens being a concave surface;

[0007] a second lens, wherein the second lens has positive power, a first side surface of the second lens is a convex surface, a second side surface is a concave surface, and the second lens is disposed on one side of the concave surface of the first lens;

[0008] a third lens, the third lens having positive optical power, a first side surface of the third lens being a convex surface, a second side surface of the third lens being a convex surface, and the third lens being disposed on one side of the convex surface of the second lens;

[0009] a fourth lens having negative optical power, a first side surface of the fourth lens being a concave surface, a second side surface of the fourth lens being a concave surface, and the fourth lens being disposed on a side of the third lens away from the second lens;

[0010] a fifth lens having negative optical power, a first side surface of the fifth lens being a concave surface, and a second side surface of the fifth lens being a convex surface, and the fifth lens being disposed on a side of the fourth lens away from the third lens;

[0011] The sixth lens has negative optical power, a first side surface of the sixth lens is a concave surface, a second side surface of the sixth lens is a concave surface, and the sixth lens is arranged on one side of the convex surface of the fifth lens.

[0012] In a feasible implementation, it also includes:

[0013] A filter, wherein the filter is disposed on one side of the second side surface of the sixth lens;

[0014] An image plane is arranged on a side of the filter away from the sixth lens.

[0015] In a feasible implementation manner, the total optical length and the effective focal length of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens after being combined satisfy 0.25≤TTL / f≤0.3; wherein TTL is the total optical length, and f is the effective focal length.

[0016] In a feasible implementation manner, the design wavelength range of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 905nm<λ<925nm.

[0017] In a feasible implementation manner, the effective focal length f of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 208mm<f<340mm.

[0018] In a feasible implementation manner, the total optical length TTL of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined satisfies TTL≤150 mm.

[0019] In a feasible implementation manner, the F number of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined satisfies 7.0≤F≤8.0.

[0020] In a feasible implementation manner, the maximum aperture of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 40 mm.

[0021] In a feasible implementation, the maximum field of view FOV of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined satisfies HFOV=1.6°VFOV=0.2°.

[0022] In a feasible implementation, it also includes:

[0023] An aperture is disposed between the fourth lens and the fifth lens.

[0024] According to a second aspect of an embodiment of the present application, a laser radar is proposed, comprising: a laser radar body; and a telephoto receiving lens as described in any one of the above.

[0025] Compared with the prior art, the utility model includes at least the following beneficial effects: the telephoto receiving lens provided in the embodiment of the present application, wherein the first lens and the second lens have positive optical focal length and both adopt a convex-concave surface type, the third lens has positive optical focal length and adopts a biconvex surface type, the fourth lens has negative optical focal length and adopts a biconcave surface type, the fifth lens has negative optical focal length and adopts a concave-convex surface type, and the sixth lens has negative optical focal length and adopts a biconcave surface type.

[0026] This technical solution rationally matches the mirror shapes of each lens of the telephoto receiving lens so that the lens has a shorter total optical length, thereby effectively controlling the size of the receiving lens and reserving installation space for the scanning module. This solves the technical problem that with the development of chip processing technology, the chip integration increases, the size increases, and the difficulty of telephoto lens design increases.

[0027] Moreover, by setting the mirror shapes of each lens, the telephoto receiving lens can simultaneously adapt to a larger image size, high resolution and low distortion, and does not affect the imaging effect due to shortening the total optical length, further improving the ease of use of the telephoto receiving lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0029] Figure 1 A structural block diagram of a telephoto receiving lens according to an embodiment of the present application;

[0030] Figure 2 A full-field point diagram of a telephoto receiving lens according to an embodiment of the present application;

[0031] Figure 3An MTF curve diagram of a telephoto receiving lens according to an embodiment of the present application;

[0032] Figure 4 An F-Tan distortion curve diagram of a telephoto receiving lens according to an embodiment of the present application;

[0033] Figure 5 A relative illumination diagram of a telephoto receiving lens according to an embodiment of the present application.

[0034] in, Figure 1 The corresponding relationship between the reference numerals and the component names is as follows:

[0035] 110, first lens; 120, second lens; 130, third lens; 140, fourth lens; 150, fifth lens; 160, sixth lens; 170, aperture; 180, filter; 190, image plane. DETAILED DESCRIPTION

[0036] In order to better understand the above-mentioned technical scheme, the technical scheme of the embodiments of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the embodiments of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0037] like Figure 1As shown, according to a first aspect of an embodiment of the present application, a telephoto receiving lens is provided, comprising: a first lens 110, wherein the first lens 110 has positive focal power, a first side surface of the first lens 110 is a convex surface, and a second side surface is a concave surface; a second lens 120, wherein the second lens 120 has positive focal power, a first side surface of the second lens 120 is a convex surface, and a second side surface is a concave surface, and the second lens 120 is arranged on one side of the concave surface of the first lens 110; and a third lens 130, wherein the third lens 130 has positive focal power, a first side surface of the third lens 130 is a convex surface, and a second side surface is a convex surface, and the third lens 130 is arranged on one side of the convex surface of the second lens 120 a fourth lens 140, wherein the fourth lens 140 has negative optical power, a first side surface of the fourth lens 140 is a concave surface, and a second side surface is a concave surface, and the fourth lens 140 is arranged on a side of the third lens 130 away from the second lens 120; a fifth lens 150, wherein the fifth lens 150 has negative optical power, a first side surface of the fifth lens 150 is a concave surface, and a second side surface is a convex surface, and the fifth lens 150 is arranged on a side of the fourth lens 140 away from the third lens 130; and a sixth lens 160, wherein the first side surface of the sixth lens 160 is a concave surface, and the second side surface is a concave surface, and the sixth lens 160 is arranged on a side of the convex surface of the fifth lens 150.

[0038] The telephoto receiving lens provided in the embodiment of the present application, wherein the first lens 110 and the second lens 120 have positive optical power and are both convex-concave, the third lens 130 has positive optical power and is biconvex, the fourth lens 140 has negative optical power and is biconcave, the fifth lens 150 has negative optical power and is concave-convex, and the sixth lens 160 has negative optical power and is biconcave.

[0039] This technical solution rationally matches the mirror shapes of each lens of the telephoto receiving lens so that the lens has a shorter total optical length, thereby effectively controlling the size of the receiving lens and reserving installation space for the scanning module. This solves the technical problem that with the development of chip processing technology, the chip integration increases, the size increases, and the difficulty of telephoto lens design increases.

[0040] Moreover, by setting the mirror shapes of each lens, the telephoto receiving lens can simultaneously adapt to a larger image size, high resolution and low distortion, and does not affect the imaging effect due to shortening the total optical length, further improving the ease of use of the telephoto receiving lens.

[0041] It is understandable that the telephoto receiving lens of the present application is used in conjunction with the scanning module to realize the forward laser radar field of view in actual use, and the relevant lens parameters can be adjusted according to actual needs. The telephoto receiving lens of the present application is limited to the receiving part of the laser radar.

[0042] like Figure 1 As shown, the telephoto receiving lens also includes: a filter 180, which is arranged on one side of the second side surface of the sixth lens 160; and an image plane 190, which is arranged on a side of the filter away from the sixth lens.

[0043] The total optical length and effective focal length of the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 after being combined satisfy 0.25≤TTL / f≤0.3.

[0044] In this technical solution, the total optical length TTL is the distance from the first side surface of the first lens 110 to the optical lens image plane 190. The lens has a small TTL / f value, which effectively shortens the total optical length while achieving telephoto, achieving the technical effect of reducing the lens volume, thereby ensuring the miniaturization of the overall volume of the laser radar.

[0045] After the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined, the design wavelength range of the optical system satisfies 905nm<λ<925nm.

[0046] After the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined, the effective focal length f of the optical system satisfies 280mm<f<340mm.

[0047] In this technical solution, the effective focal length f of the optical system is between 280 mm and 340 mm. The telephoto receiving lens in this effective focal length range is applied to the laser radar and can meet the requirements of the laser radar for receiving laser beams.

[0048] The total optical length TTL of the optical system after the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined satisfies TTL≤150 mm.

[0049] In this technical solution, the total optical length after the lens combination does not exceed 150 mm. Under this setting, the laser radar's requirements for lens size can be met.

[0050] The F number of the optical system after the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined satisfies 7.0≤F≤8.0.

[0051] The maximum aperture of the optical system after the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined is 40 mm.

[0052] After the first lens 110, the second lens 120, the third lens 130, the fourth lens 140, the fifth lens 150, the sixth lens 160, the filter 180 and the image plane 190 are combined, the maximum field of view FOV of the optical system satisfies HFOV=1.6°VFOV=0.2°.

[0053] like Figure 1 As shown, it also includes: an aperture 170, and the aperture 170 is arranged between the fourth lens 140 and the fifth lens 150.

[0054] In this technical solution, the aperture 107 can control the amount of light beam passing through, and is used to adjust the intensity of the light beam passing through the telephoto receiving lens. This technical solution improves the adaptability of the telephoto receiving lens in different light environments.

[0055] like Figure 1 As shown, according to the second aspect of an embodiment of the present application, a laser radar is proposed, comprising: a laser radar body; and a telephoto receiving lens as described in any one of the above.

[0056] In this technical solution, the high-resolution telephoto lens design for the forward laser radar receiving end described in this application realizes the improvement of imaging quality as much as possible within a limited total optical length, achieving higher resolution, and realizing better detection performance of the laser radar.

[0057] Embodiment 1:

[0058]

[0059]

[0060] Table 1

[0061] As shown in Table 1, Table 1 is related parameters of each lens in an embodiment, wherein the first side surface S1 of the first lens 110 has a curvature radius of 32.143 and a thickness of 8.587 mm.

[0062] The second side surface S2 of the first lens 110 has a curvature radius of 257.143 and a thickness of 6.496 mm.

[0063] The refractive index of the first lens 110 is 1.59.

[0064] The first side surface S3 of the second lens 120 has a curvature radius of 33.515 and a thickness of 4.564 mm.

[0065] The second side surface S4 of the second lens 120 has a curvature radius of 102.804 mm and a thickness of 0.472 mm.

[0066] The refractive index of the second lens 120 is 1.74.

[0067] The first side surface S5 of the third lens 130 has a curvature radius of 125.828 and a thickness of 3.351 mm.

[0068] The second side surface S6 of the third lens 130 has a curvature radius of -786.947 and a thickness of 1.183 mm.

[0069] The refractive index of the third lens 130 is 1.52.

[0070] The first side surface S7 of the fourth lens 140 has a curvature radius of -177.898 and a thickness of 1.48 mm.

[0071] The second side surface S8 of the fourth lens 140 has a curvature radius of 49.671 and a thickness of 2.444 mm.

[0072] The refractive index of the fourth lens 140 is 1.95.

[0073] The first side surface S9 of the fifth lens 150 has a curvature radius of -75.245 and a thickness of 4.077 mm.

[0074] The first side surface S10 of the fifth lens 150 has a curvature radius of -158.24 and a thickness of 21.628 mm.

[0075] The refractive index of the fifth lens 150 is 1.73.

[0076] The first side surface S11 of the sixth lens 160 has a curvature radius of -15.487 and a thickness of 2.21 mm.

[0077] The second side surface S12 of the sixth lens 160 has a curvature radius of 12.137 and a thickness of 31.25 mm.

[0078] The refractive index of the sixth lens 160 is 1.73.

[0079] Among them, STO is the aperture 170, and the thickness of the aperture 170 is 1.688 mm.

[0080] Wherein, S13 is the thickness of the filter 180 on the side close to the sixth lens 180, which is 0.8 mm.

[0081] S14 is the thickness of the filter 180 on the side close to the image plane 190, which is 2.564 mm.

[0082] Among them, IMA is image plane 190.

[0083] By designing the telephoto receiving lens according to the parameters in the chart, the technical solution can meet the above numerical requirements for the receiving lens. In this embodiment, the technical solution can achieve telephoto while having a shorter total optical length, adapting to a larger image plane 190 size, and having the advantages of high resolution, low distortion, and a shorter total optical length, and can achieve high-resolution detection in the laser radar while occupying less space.

[0084] At the same time, the following verifications were carried out through the optical lens of the embodiment with the above parameters, and the feasibility and preference of the technical solution were proved in the actual application process:

[0085] like Figure 2 As shown, Figure 2 This is a full-field point diagram of the technical solution in actual application. It can be seen that 0F:RMS<6.3um, 0.63F:RMS<6.5um, 1F:RMS<10um. Among them, 0F represents 0 field of view, 0.63F represents 0.63 times the maximum field of view, and 1F represents the maximum field of view. The RMS value is always controlled below 10um, which shows that the imaging quality of the telephoto receiving lens proposed by the utility model is very high.

[0086] like Figure 3 As shown, Figure 3 The MTF curve diagram of the present technical solution shows that the OTF coefficient of the lens is greater than 0.3 when the spatial frequency is 30 cycles / mm, which shows that the telephoto receiving lens proposed by the present invention has a high resolution.

[0087] like Figure 4 As shown, Figure 4 : is the F-Tan distortion curve diagram, it can be seen that the distortion is within 1%, it can be seen that the distortion degree of the telephoto receiving lens proposed by the utility model is low, and the imaging effect is better.

[0088] like Figure 5 As shown, Figure 5 is a relative illumination diagram. To match the light intensity distribution at the transmitting end, the relative illumination of the edge field of view is required to be 0.97. It can be seen from the figure that this embodiment meets the use requirements.

[0089] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0090] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as "up", "down", "left", "right", "front" and "back" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0091] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0092] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A telephoto receiving lens, characterized in that: include: A first lens, wherein the first lens has positive optical power, a first side surface of the first lens is a convex surface, and a second side surface of the first lens is a concave surface; a second lens, wherein the second lens has positive power, a first side surface of the second lens is a convex surface, a second side surface is a concave surface, and the second lens is disposed on one side of the concave surface of the first lens; a third lens, the third lens having positive optical power, a first side surface of the third lens being a convex surface, a second side surface of the third lens being a convex surface, and the third lens being disposed on one side of the concave surface of the second lens; a fourth lens having negative optical power, a first side surface of the fourth lens being a concave surface, a second side surface of the fourth lens being a concave surface, and the fourth lens being disposed on a side of the third lens away from the second lens; a fifth lens having negative optical power, a first side surface of the fifth lens being a concave surface, and a second side surface of the fifth lens being a convex surface, and the fifth lens being disposed on a side of the fourth lens away from the third lens; The sixth lens has negative optical power, a first side surface of the sixth lens is a concave surface, a second side surface of the sixth lens is a concave surface, and the sixth lens is arranged on one side of the convex surface of the fifth lens.

2. The telephoto receiving lens according to claim 1, characterized in that: Also includes: A filter, wherein the filter is disposed on one side of the second side surface of the sixth lens; An image plane is arranged on a side of the filter away from the sixth lens.

3. The telephoto receiving lens according to claim 2, characterized in that: The total optical length and effective focal length of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens after being combined satisfy 0.25≤TTL / f≤0.3; Where, TTL is the total optical length and f is the effective focal length.

4. The telephoto receiving lens according to claim 2, characterized in that: The design wavelength range of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 905nm<λ<925nm.

5. The telephoto receiving lens according to claim 2, characterized in that: The effective focal length f of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 208mm<f<340mm.

6. The telephoto receiving lens according to claim 2, characterized in that: The total optical length TTL of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined satisfies TTL≤150mm.

7. The telephoto receiving lens according to claim 2, characterized in that: The F number of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined satisfies 7.0≤F≤8.

0.

8. The telephoto receiving lens according to claim 2, characterized in that: The maximum aperture of the optical system after the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined is 40 mm; After the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the filter and the image plane are combined, the maximum field of view FOV of the optical system satisfies HFOV=1.6° VFOV=0.2°.

9. The telephoto receiving lens according to claim 1, characterized in that: Also includes: An aperture is disposed between the fourth lens and the fifth lens.

10. A laser radar, characterized in that: include: LiDAR body; A telephoto receiving lens as claimed in any one of claims 1 to 9.

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