Optical imaging lens comprising liquid lens

Abstract

The invention relates to an optical imaging lens comprising a liquid lens. The optical imaging lens comprises a first lens to a fifth lens, the liquid lens and a sixth lens to a ninth lens, the first lens has a positive refractive index, and the object side surface is a convex surface. The second lens has a negative refractive index, an object side surface is a convex surface, and an image side surface is a concave surface; the third lens has a negative refractive index, the object side surface is a concave surface, and the image side surface is a concave surface; the fourth lens has a positive refractive index, the object side surface is a concave surface, and the image side surface is a convex surface; the fifth lens has a positive refractive index, and the object side surface is a convex surface; the sixth lens has a positive refractive index, and the image side surface is a convex surface; the seventh lens has a negative refractive index, and the object side surface is a concave surface; the eighth lens has a positive refractive index, and the image side surface is a convex surface; the ninth lens has a positive refractive index, and the object side surface is a convex surface; the sixth lens and the seventh lens are glued to each other. The optical imaging lens can realize a rapid focusing function and is long in service life.

Description

Technical Field

[0001] The present invention relates to the technical field of optical lenses, and in particular to an optical imaging lens comprising a liquid lens. Background Art

[0002] In the field of machine vision, the field of view and working distance are changing, and the focus also needs to change, otherwise the image quality will be seriously affected. Lens focusing has always been a difficult problem to solve. In the past, the solution of moving the lens to change the focus has been used, which will change both the field of view and the focus.

[0003] Conventional imaging lenses struggle to capture sharp, accurate images in high-speed or precision applications that require rapid refocusing. Liquid lenses overcome these limitations by enabling rapid focus adjustment to accommodate objects at different working distances or at different heights. Liquid lenses are small components containing an optical-grade liquid that changes shape when an electric current or voltage is applied. This change occurs within milliseconds and causes the optical power of the lens to change, changing the focal length and working distance. Integrating liquid lenses into imaging systems is an ideal solution for applications that require fast focus, high throughput, and adaptability to depth of field and working distance.

[0004] In recent years, autofocus technology using curvature-variable liquid lenses has enhanced the capabilities of a single camera, avoiding complex mechanical structures, and changing numerous industries and other applications, making it instantly adaptable to different distances and types of objects. Liquid lenses are far superior to any other method in terms of speed and ease of use.

[0005] Liquid lenses are also much smaller and lighter than mechanical lenses of the same size. They do not require focusing mechanics or the need to move the lens to change focus, which reduces the size and weight of the camera. Liquid lens cameras can be used in production lines and package handling applications where space constraints prevent the installation of traditional cameras.

[0006] However, in the past two years, optical lenses equipped with liquid lenses have begun to appear on the market, but there are still some shortcomings, such as low resolution, poor imaging quality, etc. Therefore, it is still necessary to improve the optical design of optical lenses equipped with liquid lenses in the prior art. Summary of the invention

[0007] The main purpose of the present invention is to provide an optical imaging lens including a liquid lens, so as to solve the problem of poor imaging quality of the optical imaging lens in the prior art.

[0008] To achieve the above-mentioned object, a first aspect of the present invention provides an optical imaging lens including a liquid lens, which includes, from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a liquid lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens; the first lens to the ninth lens respectively include an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing the imaging light to pass through;

[0009] The first lens has a positive refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface, a convex surface or a plane surface;

[0010] The second lens has a negative refractive power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

[0011] The third lens has a negative refractive power, the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a concave surface;

[0012] The fourth lens has a positive refractive power, the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface;

[0013] The fifth lens has a positive refractive power, the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface, a convex surface or a plane surface;

[0014] The sixth lens has a positive refractive power, the object side surface of the sixth lens is a concave surface, a convex surface or a plane surface, and the image side surface of the sixth lens is a convex surface;

[0015] The seventh lens has a negative refractive power, the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface, a convex surface or a plane surface;

[0016] The eighth lens has a positive refractive power, the object side surface of the eighth lens is a concave surface, a convex surface or a plane surface, and the image side surface of the eighth lens is a convex surface;

[0017] The ninth lens has a positive refractive power, the object side surface of the ninth lens is a convex surface, and the image side surface of the ninth lens is a concave surface, a convex surface or a plane surface;

[0018] The sixth lens and the seventh lens are cemented to each other.

[0019] Preferably, the image side surface of the first lens is a concave surface;

[0020] The image side surface of the fifth lens is a concave surface;

[0021] The object side surface of the sixth lens is a plane;

[0022] The image side surface of the seventh lens is a concave surface;

[0023] The image side surface of the ninth lens is a convex surface.

[0024] Further preferably, the object-side surface of the eighth lens is a concave surface close to a plane or a convex surface close to a plane;

[0025] Furthermore, it also includes an aperture, which is arranged on the liquid lens.

[0026] Furthermore, in the direction from the object side to the image side, the liquid lens sequentially includes a first transparent surface layer, a first liquid area, an elastic membrane layer, a second liquid area and a second transparent surface layer, and the aperture is arranged on the image side surface of the first transparent surface layer, the object side surface of the first transparent surface layer, the image side surface of the second transparent surface layer or the object side surface of the second transparent surface layer.

[0027] Furthermore, the object distance varies in association with physical parameters of the liquid lens, and the physical parameters of the liquid lens include a radius of curvature of the elastic membrane layer, a central thickness of the first liquid area, and a central thickness of the second liquid area.

[0028] Further, when the object distance is 700 mm, the radius of curvature of the elastic membrane layer is 54.97 mm, the center thickness of the first liquid area is 0.542 mm, and the center thickness of the second liquid area is 1.928 mm;

[0029] When the object distance is 250 mm, the elastic membrane layer is a plane, the center thickness of the first liquid area is 0.578 mm, and the center thickness of the second liquid area is 1.892 mm;

[0030] When the object distance is 150 mm, the radius of curvature of the elastic membrane layer is -59.32 mm, the center thickness of the first liquid area is 0.612 mm, and the center thickness of the second liquid area is 1.858 mm.

[0031] Furthermore, the aperture is an ink layer.

[0032] Furthermore, the optical imaging lens meets the following requirements:

[0033] nd1>1.65, where nd1 is the refractive index of the first lens;

[0034] nd2>1.6, where nd2 is the refractive index of the second lens;

[0035] nd3>1.65, where nd3 is the refractive index of the third lens;

[0036] nd4>1.65, where nd4 is the refractive index of the fourth lens;

[0037] nd5>1.68, where nd5 is the refractive index of the fifth lens;

[0038] nd6<1.75, where nd6 is the refractive index of the sixth lens;

[0039] nd7>1.7, where nd7 is the refractive index of the seventh lens;

[0040] nd8>1.65, where nd8 is the refractive index of the eighth lens;

[0041] nd9>1.65, where nd9 is the refractive index of the ninth lens.

[0042] Furthermore, the optical imaging lens also satisfies:

[0043] Vd1<45, where Vd1 is the dispersion coefficient of the first lens;

[0044] Vd2>45, where Vd2 is the dispersion coefficient of the second lens;

[0045] Vd3<35, where Vd3 is the dispersion coefficient of the third lens;

[0046] Vd4>35, where Vd4 is the dispersion coefficient of the fourth lens;

[0047] Vd5<32, where Vd5 is the dispersion coefficient of the fifth lens;

[0048] Vd6>45, where Vd6 is the dispersion coefficient of the sixth lens;

[0049] Vd7<35, where Vd7 is the dispersion coefficient of the seventh lens;

[0050] Vd9<35, where Vd9 is the dispersion coefficient of the ninth lens.

[0051] Furthermore, the optical imaging lens also satisfies: 0.18≤BFL / TTL≤0.25; wherein BFL is the distance from the image side surface of the ninth lens to the imaging surface on the optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis.

[0052] Furthermore, the optical imaging lens also satisfies: 1≤f 后组 / f≤1.5; where f 后组 is the combined focal length of the sixth lens to the ninth lens, and f is the focal length of the optical imaging lens.

[0053] The optical imaging lens of the present invention can quickly adjust the focal length by integrating a liquid lens to adapt to objects with different working distances and depths of field requirements, especially in high-speed or precision imaging applications, and can significantly improve the accuracy and speed of imaging; and through the refractive powers, surface curvatures and arrangement order of the first to ninth lenses mentioned above, the transmission path of light and the imaging quality are optimized, aberrations and distortions are reduced, thereby improving the resolution and imaging clarity of the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a schematic structural diagram of an optical imaging lens in one embodiment;

[0055] Figure 2 is a schematic structural diagram of a liquid lens in one embodiment;

[0056] Figure 3 is a diagram of the light spot focusing points of the optical imaging lens when the object distance is 150 mm in one embodiment;

[0057] Figure 4 is a diagram of the light spot focusing points of the optical imaging lens when the object distance is 250 mm in one embodiment;

[0058] Figure 5 is a diagram of the light spot focusing points of the optical imaging lens when the object distance is 700 mm in one embodiment;

[0059] Figure 6 1 is a graph showing (a) astigmatism and (b) distortion of an optical imaging lens when the object distance is 150 mm in one embodiment;

[0060] Figure 7 1 is a graph showing (a) astigmatism and (b) distortion of an optical imaging lens when the object distance is 250 mm in one embodiment;

[0061] Figure 8 1 and 10 are (a) astigmatism and (b) distortion curves of an optical imaging lens when the object distance is 700 mm in one embodiment.

[0062] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0064] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0065] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0066] The lens mentioned in the embodiments of the present invention, if it has a positive refractive power (or negative refractive power), means that the paraxial refractive power calculated according to Gaussian optical theory is positive (or negative). The object side (or image side) of the lens specifically refers to the specific area on the lens surface where the imaging light penetrates. The concave and convex judgment of the lens surface shape follows the conventional judgment method of the general knowledge in this field, that is, it is judged based on the positive and negative signs of the radius of curvature (abbreviated as R value). R value is widely used in optical design software, such as Zemax or CodeV, and is commonly seen in lens data sheets.

[0067] Specifically, for the object side surface, when the R value is positive, the object side surface is determined to be convex; when the R value is negative, the object side surface is determined to be concave. Correspondingly, for the image side surface, when the R value is positive, the image side surface is determined to be concave; when the R value is negative, the image side surface is determined to be convex.

[0068] Reference Figure 1 An embodiment of the present invention discloses an optical imaging lens including a liquid lens, which includes, from the object side to the image side, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a liquid lens 10, a sixth lens 6, a seventh lens 7, an eighth lens 8 and a ninth lens 9; the first lens 1 to the ninth lens 9 respectively include an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing the imaging light to pass through;

[0069] The first lens 1 has a positive refractive power, the object side surface 11 of the first lens is a convex surface, and the image side surface 12 of the first lens is a concave surface, a convex surface or a plane surface;

[0070] The second lens 2 has a negative refractive power, the object side surface 21 of the second lens is a convex surface, and the image side surface 22 of the second lens is a concave surface;

[0071] The third lens 3 has a negative refractive power, the object side surface 31 of the third lens is a concave surface, and the image side surface 32 of the third lens is a concave surface;

[0072] The fourth lens 4 has a positive refractive power, the object side surface 41 of the fourth lens is a concave surface, and the image side surface 42 of the fourth lens is a convex surface;

[0073] The fifth lens 5 has a positive refractive power, the object side surface 51 of the fifth lens is a convex surface, and the image side surface 52 of the fifth lens is a concave surface, a convex surface or a plane surface;

[0074] The sixth lens 6 has a positive refractive power, the object side surface 61 of the sixth lens is a concave surface, a convex surface or a plane surface, and the image side surface 62 of the sixth lens is a convex surface;

[0075] The seventh lens 7 has a negative refractive power, the object side surface 71 of the seventh lens is a concave surface, and the image side surface 72 of the seventh lens is a concave surface, a convex surface or a plane surface;

[0076] The eighth lens 8 has a positive refractive power, the object side surface 81 of the eighth lens is a concave surface, a convex surface or a plane surface, and the image side surface 82 of the eighth lens is a convex surface;

[0077] The ninth lens 9 has a positive refractive power, the object side surface 91 of the ninth lens is a convex surface, and the image side surface 92 of the ninth lens is a concave surface, a convex surface or a plane surface;

[0078] The sixth lens 6 and the seventh lens 7 are glued to each other.

[0079] The above-mentioned optical imaging lens further includes a filter 01 and an image sensor 02 which are arranged on the image side of the ninth lens.

[0080] The optical lens of the present invention can quickly adjust the focal length by integrating the liquid lens 10 to adapt to objects with different working distances and depth of field requirements, especially in high-speed or precision imaging applications, and can significantly improve the accuracy and speed of imaging. And through the refractive power, surface curvature and arrangement order of the first to ninth lenses mentioned above, the transmission path of light and the imaging quality are optimized, and the aberration and distortion are reduced, thereby improving the resolution and imaging clarity of the lens.

[0081] The present invention uses a liquid lens for focusing without changing the optical back focus and mechanical back focus of the lens. For objects at different distances, the voltage is used to drive the curvature radius of the liquid lens to change, and the image can be refocused onto the optical sensitive surface of the camera detector. Since there is no mechanical structure, the fast focusing function can be achieved, and the service life is long, which can reach hundreds of millions of times.

[0082] As a preferred embodiment of the present invention, the image side surface 12 of the first lens is a concave surface; the image side surface 52 of the fifth lens is a concave surface; the object side surface 61 of the sixth lens is a plane; the image side surface 72 of the seventh lens is a concave surface; the object side surface 81 of the eighth lens is a concave surface close to a plane or a convex surface close to a plane; the image side surface 92 of the ninth lens is a convex surface.

[0083] Reference Figure 2 In a specific embodiment, it also includes an aperture 101, and the aperture 101 is arranged on the liquid lens 10. The liquid lens 10 is located between the fifth lens 5 and the sixth lens 6, that is, in the middle of the entire optical lens. The aperture 101 is arranged on the liquid lens 10 to achieve the centering of the aperture, which can maximize the use of the liquid lens aperture, increase the light transmission effect of the optical lens, ensure its compact structure, and reduce the total length. The liquid lens 10 used in the present invention can be obtained by selecting parameters from the liquid lens in the prior art. Its principle adopts the voltage control principle of a general liquid lens, which will not be elaborated in the present invention.

[0084] In a specific embodiment, in the direction from the object side to the image side, the liquid lens 10 includes a first transparent surface layer 102, a first liquid area 103, an elastic film layer 104, a second liquid area 105 and a second transparent surface layer 106 in sequence, and the aperture 101 is arranged on the image side of the first transparent surface layer 102, the object side of the first transparent surface layer 102, the image side of the second transparent surface layer 106 or the object side of the second transparent surface layer. As a more preferred embodiment, the aperture 101 is arranged on the object side of the first transparent surface layer 102 or the image side of the second transparent surface layer 106, so as to reduce the caliber of the liquid area, that is, to improve the liquid utilization rate of the first liquid area 103 and the second liquid area 105. The first surface layer 102 and the second transparent surface layer 106 are preferably made of glass, and the liquids of the first liquid area 103 and the second liquid area 105 are selected from oily solutions and aqueous solutions respectively. The elastic film layer 104 is made of a material with high elasticity and high transparency, such as silicone rubber or a specially made polymer film.

[0085] In a specific embodiment, the object distance varies in association with physical parameters of the liquid lens, and the physical parameters of the liquid lens include a radius of curvature of the elastic membrane layer, a central thickness of the first liquid area, and a central thickness of the second liquid area.

[0086] In a specific embodiment, the selected liquid lens has the following characteristics:

[0087] When the object distance is 700 mm, the radius of curvature of the elastic membrane layer is 54.97 mm, the center thickness of the first liquid area is 0.542 mm, and the center thickness of the second liquid area is 1.928 mm;

[0088] When the object distance is 250 mm, the elastic membrane layer is a plane, the center thickness of the first liquid area is 0.578 mm, and the center thickness of the second liquid area is 1.892 mm;

[0089] When the object distance is 150 mm, the radius of curvature of the elastic membrane layer is -59.32 mm, the center thickness of the first liquid area is 0.612 mm, and the center thickness of the second liquid area is 1.858 mm.

[0090] In a specific embodiment, the aperture is an ink layer.

[0091] The ink layer diaphragm design simplifies the structure of the optical imaging lens, reduces the mechanical parts and assembly process required for the traditional diaphragm, and reduces the manufacturing cost and complexity of the lens. In addition, the ink layer diaphragm has higher manufacturing precision, which can achieve more precise diaphragm pattern and opening size control, thereby improving the imaging quality and performance of the lens.

[0092] In a specific embodiment, the optical imaging lens satisfies:

[0093] nd1>1.65, where nd1 is the refractive index of the first lens;

[0094] nd2>1.6, where nd2 is the refractive index of the second lens;

[0095] nd3>1.65, where nd3 is the refractive index of the third lens;

[0096] nd4>1.65, where nd4 is the refractive index of the fourth lens;

[0097] nd5>1.68, where nd5 is the refractive index of the fifth lens;

[0098] nd6<1.75, where nd6 is the refractive index of the sixth lens;

[0099] nd7>1.7, where nd7 is the refractive index of the seventh lens;

[0100] nd8>1.65, where nd8 is the refractive index of the eighth lens;

[0101] nd9>1.65, where nd9 is the refractive index of the ninth lens.

[0102] In a specific embodiment, the optical imaging lens further satisfies:

[0103] Vd1<45, where Vd1 is the dispersion coefficient of the first lens;

[0104] Vd2>45, where Vd2 is the dispersion coefficient of the second lens;

[0105] Vd3<35, where Vd3 is the dispersion coefficient of the third lens;

[0106] Vd4>35, where Vd4 is the dispersion coefficient of the fourth lens;

[0107] Vd5<32, where Vd5 is the dispersion coefficient of the fifth lens;

[0108] Vd6>45, where Vd6 is the dispersion coefficient of the sixth lens;

[0109] Vd7<35, where Vd7 is the dispersion coefficient of the seventh lens;

[0110] Vd9<35, where Vd9 is the dispersion coefficient of the ninth lens.

[0111] In a specific embodiment, the optical imaging lens further satisfies: 0.18≤BFL / TTL≤0.25; wherein BFL is the distance from the image side surface of the ninth lens to the imaging surface on the optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis.

[0112] In the present invention, the optical imaging lens within the above ratio range can maintain good aberration correction capability, ensure the clarity and contrast of the imaging, and reduce the volume as much as possible while ensuring the imaging quality.

[0113] In a specific embodiment, the optical imaging lens further satisfies: 1≤f 后组 / f≤1.5; where f 后组 is the combined focal length of the sixth lens to the ninth lens, and f is the focal length of the optical imaging lens.

[0114] By controlling the focal length of the rear lens group within the above range, it helps to reduce aberrations, especially field curvature and distortion, so that the lens can maintain good imaging quality at a wider field of view. At the same time, within the above ratio range, the focal length of the rear lens group will not be too large, resulting in a lens that is too long, nor too small, making it difficult to correct aberrations, which helps to achieve a compact design of the optical lens.

[0115] The optical imaging lens including the liquid lens of the present invention is described in detail below with reference to specific embodiments.

[0116] Embodiment 1

[0117] like Figure 1 As shown, an optical imaging lens including a liquid lens comprises, from the object side to the image side of the optical imaging lens, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a liquid lens 10, a sixth lens 6, a seventh lens 7, an eighth lens 8 and a ninth lens 9; the first lens 1 to the ninth lens 9 respectively comprise an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing the imaging light to pass through;

[0118] The first lens 1 has a positive refractive power, the object side surface 11 of the first lens is a convex surface, and the image side surface 12 of the first lens is a concave surface;

[0119] The second lens 2 has a negative refractive power, the object side surface 21 of the second lens is a convex surface, and the image side surface 22 of the second lens is a concave surface;

[0120] The third lens 3 has a negative refractive power, the object side surface 31 of the third lens is a concave surface, and the image side surface 32 of the third lens is a concave surface;

[0121] The fourth lens 4 has a positive refractive power, the object side surface 41 of the fourth lens is a concave surface, and the image side surface 42 of the fourth lens is a convex surface;

[0122] The fifth lens 5 has a positive refractive power, the object side surface 51 of the fifth lens is a convex surface, and the image side surface 52 of the fifth lens is a concave surface;

[0123] The sixth lens 6 has a positive refractive power, the object side surface 61 of the sixth lens is a plane, and the image side surface 62 of the sixth lens is a convex surface;

[0124] The seventh lens element 7 has a negative refractive power, the object side surface 71 of the seventh lens element is a concave surface, and the image side surface 72 of the seventh lens element is a concave surface;

[0125] The eighth lens 8 has a positive refractive power, the object side surface 81 of the eighth lens is a concave surface, and the image side surface 82 of the eighth lens is a convex surface;

[0126] The ninth lens element 9 has a positive refractive power, an object side surface 91 of the ninth lens element is a convex surface, and an image side surface 92 of the ninth lens element is a convex surface;

[0127] The sixth lens 6 and the seventh lens 7 are glued to each other.

[0128] The detailed optical data of this embodiment 1 is shown in Table 1.

[0129] Table 1 Optical data list of Example 1

[0130]

[0131]

[0132] The values ​​of D1 and D2 of the liquid lens 10 are shown in Table 2.

[0133] Table 2 Liquid lens parameters corresponding to different object distances

[0134]

[0135] The focus spot sizes of different working object distances (150mm, 250mm, 700mm) in this specific embodiment are detailed in Figure 3-Figure 5 , it can be seen that the focused spot size is small and the imaging clarity of the optical imaging lens is high.

[0136] For details of astigmatism and distortion curves at different working object distances (150mm, 250mm, 700mm), please see Figure 6-Figure 8 It can be seen that the astigmatism and distortion of the optical imaging lens of this embodiment are small, and the distortion amount is less than 1.4%.

[0137] In this specific embodiment, the BFL / TTL of the optical imaging lens is 0.22, f 后组 / f=1.29.

[0138] Obviously, the embodiments described above are only some embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are given in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific embodiments, or to perform equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of the present invention, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. An optical imaging lens including a liquid lens, characterized in that: The optical imaging lens includes, from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a liquid lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens; the first lens to the ninth lens respectively include an object-side surface facing the object side and allowing imaging light to pass through, and an image-side surface facing the image side and allowing the imaging light to pass through; The first lens has a positive refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface, a convex surface or a plane surface; The second lens has a negative refractive power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; The third lens has a negative refractive power, the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a concave surface; The fourth lens has a positive refractive power, the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; The fifth lens has a positive refractive power, the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface, a convex surface or a plane surface; The sixth lens has a positive refractive power, the object side surface of the sixth lens is a concave surface, a convex surface or a plane surface, and the image side surface of the sixth lens is a convex surface; The seventh lens has a negative refractive power, the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface, a convex surface or a plane surface; The eighth lens has a positive refractive power, the object side surface of the eighth lens is a concave surface, a convex surface or a plane surface, and the image side surface of the eighth lens is a convex surface; The ninth lens has a positive refractive power, the object side surface of the ninth lens is a convex surface, and the image side surface of the ninth lens is a concave surface, a convex surface or a plane surface; The sixth lens and the seventh lens are cemented to each other.

2. The optical imaging lens comprising a liquid lens as claimed in claim 1, wherein: It also includes an aperture, which is arranged on the liquid lens.

3. The optical imaging lens including a liquid lens as claimed in claim 2, wherein: In the direction from the object side to the image side, the liquid lens includes a first transparent surface layer, a first liquid area, an elastic membrane layer, a second liquid area and a second transparent surface layer in sequence, and the aperture is arranged on the image side surface of the first transparent surface layer, the object side surface of the first transparent surface layer, the image side surface of the second transparent surface layer or the object side surface of the second transparent surface layer.

4. The optical imaging lens including a liquid lens as claimed in claim 3, characterized in that: The object distance varies in association with physical parameters of the liquid lens, and the physical parameters of the liquid lens include a radius of curvature of the elastic membrane layer, a central thickness of the first liquid area, and a central thickness of the second liquid area.

5. The optical imaging lens including a liquid lens as claimed in claim 4, characterized in that: When the object distance is 700 mm, the radius of curvature of the elastic membrane layer is 54.97 mm, the center thickness of the first liquid area is 0.542 mm, and the center thickness of the second liquid area is 1.928 mm; When the object distance is 250 mm, the elastic membrane layer is a plane, the center thickness of the first liquid area is 0.578 mm, and the center thickness of the second liquid area is 1.892 mm; When the object distance is 150 mm, the radius of curvature of the elastic membrane layer is -59.32 mm, the center thickness of the first liquid area is 0.612 mm, and the center thickness of the second liquid area is 1.858 mm.

6. The optical imaging lens including a liquid lens as claimed in claim 2, wherein: The aperture is an ink layer.

7. The optical imaging lens including a liquid lens as claimed in claim 1, wherein: The optical imaging lens meets the following requirements: nd1>1.65, where nd1 is the refractive index of the first lens; nd2>1.6, where nd2 is the refractive index of the second lens; nd3>1.65, where nd3 is the refractive index of the third lens; nd4>1.65, where nd4 is the refractive index of the fourth lens; nd5>1.68, where nd5 is the refractive index of the fifth lens; nd6<1.75, where nd6 is the refractive index of the sixth lens; nd7>1.7, where nd7 is the refractive index of the seventh lens; nd8>1.65, where nd8 is the refractive index of the eighth lens; nd9>1.65, where nd9 is the refractive index of the ninth lens.

8. The optical imaging lens including a liquid lens as claimed in claim 7, wherein: The optical imaging lens also meets the following requirements: Vd1<45, where Vd1 is the dispersion coefficient of the first lens; Vd2>45, where Vd2 is the dispersion coefficient of the second lens; Vd3<35, where Vd3 is the dispersion coefficient of the third lens; Vd4>35, where Vd4 is the dispersion coefficient of the fourth lens; Vd5<32, where Vd5 is the dispersion coefficient of the fifth lens; Vd6>45, where Vd6 is the dispersion coefficient of the sixth lens; Vd7<35, where Vd7 is the dispersion coefficient of the seventh lens; Vd9<35, where Vd9 is the dispersion coefficient of the ninth lens.

9. The optical imaging lens including a liquid lens as claimed in claim 1, wherein: The optical imaging lens further satisfies: 0.18≤BFL / TTL≤0.25; wherein BFL is the distance from the image side surface of the ninth lens to the imaging surface on the optical axis, and TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis.

10. The optical imaging lens including a liquid lens as claimed in claim 1, wherein: The optical imaging lens also satisfies: 1≤f 后组 / f≤1.5; where f 后组 is the combined focal length of the sixth lens to the ninth lens, and f is the focal length of the optical imaging lens.

Images