Imaging lens

Abstract

An imaging lens includes first, second, third and fourth lenses. The first lens is a meniscus lens with positive refractive power. The second lens has negative refractive power. The third lens has positive refractive power. The fourth lens is a meniscus lens. The first, second, third and fourth lenses are arranged in order from an object side to an image side along an optical axis. The imaging lens satisfies at least one of the following conditions: -0.1≤R11 / R42≤0.53; 2≤TTL / SD4≤7; 0.1≤SD1 / f≤0.6; wherein R11 is a curvature radius of an object side surface of the first lens, R42 is a curvature radius of an image side surface of the fourth lens, TTL is a distance along the optical axis from the object side surface of the first lens to an imaging surface, SD4 is an optical effective diameter of the fourth lens, SD1 is an optical effective diameter of the first lens, and f is an effective focal length of the imaging lens.

Description

Technical Field

[0001] This invention relates to an imaging lens. Background Technology

[0002] The current trend in imaging lens development is towards higher resolution. As the number of lenses used in imaging lenses increases, the overall length of the lenses becomes longer and longer, which can no longer meet the requirements for miniaturization. Therefore, a new imaging lens architecture is needed to simultaneously meet the requirements of high resolution and miniaturization. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an imaging lens that has a shorter total length, higher resolution, and still good optical performance, in view of the above-mentioned defects of the prior art.

[0004] The technical solution adopted by this invention to solve its technical problem is to provide an imaging lens, including a first lens, a second lens, a third lens, and a fourth lens. The first lens has positive refractive power; this first lens is a meniscus lens and includes a convex surface facing the object side and a concave surface facing the image side. The second lens has negative refractive power. The third lens has positive refractive power. The fourth lens has refractive power; this fourth lens is a meniscus lens. The first, second, third, and fourth lenses are arranged sequentially along the optical axis from the object side to the image side. The imaging lens satisfies at least one of the following conditions: -0.1≤R11 / R42≤0.53; 2≤TTL / SD4≤7; 0.1≤SD1 / f≤0.6; where R11 is the radius of curvature of the object side surface of the first lens, R42 is the radius of curvature of the image side surface of the fourth lens, TTL is the distance along the optical axis from the object side surface of the first lens to the imaging plane, SD4 is the optically effective diameter of the fourth lens, SD1 is the optically effective diameter of the first lens, and f is the effective focal length of the imaging lens. When the imaging lens of the present invention meets the above-mentioned features and conditions and no other additional features or conditions are required, the basic function of the imaging lens of the present invention can be achieved.

[0005] The second lens includes a concave surface facing the image side, and the third lens is a biconvex lens, including a convex surface facing the object side and another convex surface facing the image side.

[0006] The fourth lens has positive refractive power.

[0007] The fourth lens has negative refractive power.

[0008] The second lens includes a concave surface facing the object side, and the fourth lens includes a convex surface facing the object side and a concave surface facing the image side.

[0009] The second lens includes a convex surface facing the object side, and the fourth lens includes a concave surface facing the object side and a convex surface facing the image side.

[0010] When the second lens includes a convex surface facing the object side, the fourth lens includes a concave surface facing the object side and a convex surface facing the image side; when the second lens includes a concave surface facing the object side, the fourth lens includes a convex surface facing the object side and a concave surface facing the image side.

[0011] The imaging lens of the present invention may further include an aperture disposed between the first lens and the second lens.

[0012] The imaging lens of the present invention may further include an aperture disposed between the first lens and the second lens, wherein the imaging lens satisfies at least one of the following conditions: 0≤SD4 / TTL≤0.5; 0.05≤SL1 / TTL≤0.5; 0.1≤SD4 / SL2≤0.8; wherein TTL is the distance between the object side surface of the first lens and the imaging surface along the optical axis, SD4 is the optically effective diameter of the fourth lens, SL1 is the distance between the object side surface of the first lens and the aperture along the optical axis, and SL2 is the distance between the aperture and the imaging surface along the optical axis.

[0013] The imaging lens satisfies at least one of the following conditions: -10≤f4 / BFL≤-3; 19≤|f4 / BFL|≤52; where f4 is the effective focal length of the fourth lens, and BFL is the distance along the optical axis from the image side of the fourth lens to the imaging plane.

[0014] The imaging lens implementing the present invention has the following advantages: its total length is relatively short and its resolution is relatively high, but it still has good optical performance. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the lens configuration and optical path according to a first embodiment of the imaging lens of the present invention.

[0016] Figure 2A , 2B 2C are field curvature, distortion, and modulation transfer function diagrams according to the first embodiment of the imaging lens of the present invention.

[0017] Figure 3 This is a schematic diagram of the lens configuration and optical path according to a second embodiment of the imaging lens of the present invention.

[0018] Figure 4A , 4B 4C are the field curvature diagram, distortion diagram, and modulation conversion function diagram of the imaging lens according to the second embodiment of the present invention.

[0019] Figure 5This is a schematic diagram of the lens configuration and optical path according to a third embodiment of the imaging lens of the present invention.

[0020] Figure 6A , 6B 6C are field curvature diagrams, distortion diagrams, and modulation conversion function diagrams according to a third embodiment of the imaging lens of the present invention.

[0021] Figure 7 This is a schematic diagram of the lens configuration and optical path according to the fourth embodiment of the imaging lens of the present invention.

[0022] Figure 8A , 8B 8C are field curvature diagrams, distortion diagrams, and modulation conversion function diagrams according to the fourth embodiment of the imaging lens of the present invention.

[0023] Figure 9 This is a schematic diagram of the lens configuration and optical path according to the fifth embodiment of the imaging lens of the present invention.

[0024] Figure 10 This is a schematic diagram of the lens configuration and optical path according to the sixth embodiment of the imaging lens of the present invention.

[0025] Figure 11 This is a schematic diagram of the lens configuration and optical path of the imaging lens according to the seventh embodiment of the present invention. Detailed Implementation

[0026] This invention provides an imaging lens, comprising: a first lens having positive refractive power, wherein the first lens is a meniscus lens and includes a convex surface facing the object side and a concave surface facing the image side; a second lens having negative refractive power; a third lens having positive refractive power; and a fourth lens having refractive power, wherein the fourth lens is a meniscus lens; wherein the first lens, the second lens, the third lens, and the fourth lens are arranged sequentially along the optical axis from the object side to the image side; wherein the imaging lens satisfies at least one of the following conditions: -0.1≤R11 / R42≤0.53; 2≤TTL / SD4≤7; 0.1≤SD1 / f≤0.6; wherein R11 is the radius of curvature of the object side surface of the first lens, R42 is the radius of curvature of the image side surface of the fourth lens, TTL is the distance from the object side surface of the first lens to the imaging surface along the optical axis, SD4 is the optically effective diameter of the fourth lens, SD1 is the optically effective diameter of the first lens, and f is the effective focal length of the imaging lens.

[0027] Please refer to Tables 1, 2, 4, 5, 7, 8, 10, 11, 13, 14, 16, 17, 19, and 20 below. Tables 1, 4, 7, 10, 13, 16, and 19 are the relevant parameter tables for each lens in the first to seventh embodiments of the imaging lens according to the present invention. Tables 2, 5, 8, 11, 14, 17, and 20 are the relevant parameter tables for the aspherical surfaces of the aspherical lenses in Tables 1, 4, 7, 10, 13, 16, and 19, respectively.

[0028] Figure 1 , 3 Figures 5, 7, 9, 10, and 11 are schematic diagrams of lens configuration and optical path in the first, second, third, fourth, fifth, sixth, and seventh embodiments of the imaging lens of the present invention. Among them, the first lenses L11, L21, L31, L41, L51, L61, and L71 are meniscus lenses with positive refractive power, made of glass, and their object-side surfaces S11, S21, S31, S41, S51, S61, and S71 are convex surfaces, while their image-side surfaces S12, S22, S32, S42, S52, S62, and S72 are concave surfaces, and all are aspherical surfaces.

[0029] The second lenses L12, L22, L32, L42, L52, L62, and L72 have negative refractive power and are made of plastic. Their image-side surfaces S15, S25, S35, S45, S55, S65, and S75 are concave, while their object-side surfaces S14, S24, S34, S44, S54, S64, and S74, as well as their image-side surfaces S15, S25, S35, S45, S55, S65, and S75, are all aspherical surfaces.

[0030] The third lenses L13, L23, L33, L43, L53, L63, and L73 are biconvex lenses, which help to lengthen the back focal distance and have positive refractive power. They are made of plastic, and their object side surfaces S16, S26, S36, S46, S56, S66, and S76 are convex, while their image side surfaces S17, S27, S37, S47, S57, S67, and S77 are convex. All of them are aspherical surfaces.

[0031] The fourth lenses L14, L24, L34, L44, L54, L64, and L74 are meniscus lenses with refractive power. They are made of plastic, and their object-side surfaces S18, S28, S38, S48, S58, S68, and S78, as well as their image-side surfaces S19, S29, S39, S49, S59, S69, and S79, are all aspherical surfaces.

[0032] The above positive-negative-positive refractive architecture helps to improve resolution, correct aberrations, and correct chromatic aberration. In addition, imaging lenses 1, 2, 3, 4, 5, 6, and 7 satisfy at least one of the following conditions (1) to (8):

[0033] -0.1≤R11 / R42≤0.53; (1)

[0034] 2≤TTL / SD4≤7; (2)

[0035] -10≤f4 / BFL≤-3; (3)

[0036] 0≤SD4 / TTL≤0.5; (4)

[0037] 0.05≤SL1 / TTL≤0.5; (5)

[0038] 0.1≤SD4 / SL2≤0.8; (6)

[0039] 0.1≤SD1 / f≤0.6; (7)

[0040] 19≤|f4 / BFL|≤52; (8)

[0041] Among them, R 11 In the first to seventh embodiments, the radii of curvature R of the object-side surfaces S11, S21, S31, S41, S51, S61, and S71 of the first lenses L11, L21, L31, L41, L51, L61, and L71 are respectively. 42In the first to seventh embodiments, the image-side surfaces S19, S29, S39, S49, S59, S69, and S79 of the fourth lenses L14, L24, L34, L44, L54, L64, and L74 are radii of curvature. TTL represents the object-side surfaces S11, S21, S31, S41, S51, S61, and S71 of the first lenses L11, L21, L31, L41, L51, L61, and L71, respectively, extending along the optical axes OA1, OA2, OA3, IMA4, IMA5, IMA6, and IMA7 to the imaging planes IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, and IMA7 in the first to seventh embodiments. 3. The spacing between OA4, OA5, OA6, and OA7; BFL represents the spacing between the image-side surfaces S19, S29, S39, S49, S59, S69, and S79 of the fourth lenses L14, L24, L34, L44, L54, L64, and L74 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, and OA7 from the imaging surfaces IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, and IMA7 in the first to seventh embodiments; f represents the effective focal length of the imaging lenses 1, 2, 3, 4, 5, 6, and 7 in the first to seventh embodiments; f4 represents the effective focal length of the imaging lenses 1, 2, 3, 4, 5, 6, and 7. In the first to seventh embodiments, SD1 represents the effective focal length of the fourth lenses L14, L24, L34, L44, L54, L64, and L74; SD4 represents the effective optical diameter of the first lenses L11, L21, L31, L41, L51, L61, and L71; SD4 represents the effective optical diameter of the fourth lenses L14, L24, L34, L44, L54, L64, and L74; and SL1 represents the object-side surface of the first lenses L11, L21, L31, L41, L51, L61, and L71 in the first to seventh embodiments. S11, S21, S31, S41, S51, S61, and S71 represent the distances from apertures ST1, ST2, ST3, ST4, ST5, ST6, and ST7 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, and OA7, respectively. SL2 represents the distances from apertures ST1, ST2, ST3, ST4, ST5, ST6, and ST7 to imaging planes IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, and IMA7 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, and OA7, respectively, in the first to seventh embodiments. This allows imaging lenses 1, 2, 3, 4, 5, 6, and 7 to effectively reduce the overall lens length, effectively improve resolution, effectively correct aberrations, and effectively correct chromatic aberration.

[0042] When condition (1) is met: -0.1≤R11 / R42≤0.53, the manufacturability of the first lens side surface can be effectively controlled, enabling the system to effectively distribute bending forces and reduce system sensitivity. When condition (2) is met: 2≤TTL / SD4≤7, the total length of the imaging lens can be effectively controlled. When condition (3) is met: -10≤f4 / BFL≤-3, the back focal length of the imaging lens can be effectively controlled. When condition (4) is met: 0≤SD4 / TTL≤0.5, the total length of the imaging lens can be effectively controlled. When condition (5) is met: 0.05≤SL1 / TTL≤0.5, the focal length of the imaging lens can be effectively controlled. When condition (6) is met: 0.1≤SD4 / SL2≤0.8, the outer diameter of the imaging lens can be effectively controlled. When condition (7) is met: 0.1≤SD1 / f≤0.6, the focal length of the imaging lens can be effectively controlled. When condition (8) is met: 19≤|f4 / BFL|≤52, the back focal length of the imaging lens can be effectively controlled.

[0043] The first embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 1 The imaging lens 1 includes a first lens L11, an aperture ST1, a second lens L12, a third lens L13, a fourth lens L14, and a filter OF1. The first lens L11, aperture ST1, second lens L12, third lens L13, fourth lens L14, and filter OF1 are arranged sequentially along the optical axis OA1 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA1. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0044] The second lens L12 is a biconcave lens with its object side S14 being concave; the fourth lens L14 is a meniscus lens with negative refractive power, with its object side S18 being convex and its image side S19 being concave; the filter OF1 has its object side S110 and image side S111 both being planar; the combined focal length of the second lens L12, the third lens L13 and the fourth lens L14 is -12.7753mm; by utilizing the above-mentioned lens, aperture ST1 and the design that satisfies at least one of the conditions (1) to (7), the imaging lens 1 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0045] Table 1 is... Figure 1 The relevant parameter table of each lens in the imaging lens 1. When the refractive power, surface shape and conditions (1) to (7) of each lens in Table 1 are met, it is a preferred embodiment of the present invention.

[0046] Table 1

[0047]

[0048] The aspherical surface concavity z of the aspherical lens in Table 1 is obtained by the following formula: z = ch 2 / {1+[1-(k+1)c 2 h 2 ] 1 / 2}+Ah 3 +Bh 4 +Ch 5 +Dh 6 +Eh 7 +Fh 8 +Gh 9 +Hh 10 +Ih 12 +Jh 14 +Kh 16 +Lh 18 +Mh 20 Where: c: curvature; h: perpendicular distance from any point on the lens surface to the optical axis; k: conic constant; A~M: aspherical coefficients. Table 2 is a table of relevant parameters for the aspherical surface of the aspherical lens in Table 1, where k is the conic constant and A~M are the aspherical coefficients.

[0049] Table 2

[0050]

[0051] Table 3 shows the relevant parameter values ​​of the imaging lens 1 in the first embodiment and the calculated values ​​of the corresponding conditions (1) to (7). As can be seen from Table 3, the imaging lens 1 in the first embodiment can meet the requirements of conditions (1) to (7).

[0052] Table 3

[0053] BFL 9.788mm SD1 5.000mm SD4 3.280mm SL1 1.870mm SL2 13.668mm R11 / R42 0.298 TTL / SD4 4.738 f4 / BFL -6.375 SD4 / TTL 0.211 SL1 / TTL 0.120 SD4 / SL2 0.240 SD1 / f 0.301

[0054] Furthermore, the optical performance of the imaging lens 1 in the first embodiment also meets the requirements. Figure 2A It can be seen that the field curvature of the imaging lens 1 in the first embodiment is between -0.10mm and 0.3mm. Figure 2B It can be seen that the distortion of the imaging lens 1 in the first embodiment is between 0% and 1%. Figure 2C It can be seen that the modulation transfer function value of the imaging lens 1 in the first embodiment is between 0.44 and 1.0. Clearly, the field curvature and distortion of the imaging lens 1 in the first embodiment can be effectively corrected, and the lens resolution can meet the requirements, thus achieving better optical performance.

[0055] The second embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 3Imaging lens 2 includes a first lens L21, an aperture ST2, a second lens L22, a third lens L23, a fourth lens L24, and a filter OF2. The first lens L21, aperture ST2, second lens L22, third lens L23, fourth lens L24, and filter OF2 are arranged sequentially along the optical axis OA2 from the object side to the image side. During imaging, light rays from the object side are finally imaged onto the imaging plane IMA2. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0056] The second lens L22 is a biconcave lens with its object side S24 being concave; the fourth lens L24 is a meniscus lens with negative refractive power, with its object side S28 being convex and its image side S29 being concave; the filter OF2 has its object side S210 and image side S211 both being planar; the combined focal length of the second lens L22, the third lens L23 and the fourth lens L24 is -12.7753mm; by using the above lens, aperture ST2 and the design that satisfies at least one of the conditions (1) to (7), the imaging lens 2 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0057] Table 4 is... Figure 3 The relevant parameters of each lens in the imaging lens 2 are shown in Table 4. When the refractive power, surface shape and conditions (1) to (7) of each lens are met, it is a preferred embodiment of the present invention.

[0058] Table 4

[0059]

[0060]

[0061] The definition of the aspherical surface concavity z of the aspherical lens in Table 4 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 5 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 4, where k is the conic constant and A to M are the aspherical coefficients.

[0062] Table 5

[0063]

[0064] Table 6 shows the relevant parameter values ​​of the imaging lens 2 in the second embodiment and the calculated values ​​of the corresponding conditions (1) to (7). As can be seen from Table 6, the imaging lens 2 in the second embodiment can meet the requirements of conditions (1) to (7).

[0065] Table 6

[0066] BFL 9.796mm SD1 5.000mm SD4 3.184mm SL1 1.870mm SL2 13.861mm R11 / R42 0.436 TTL / SD4 4.941 f4 / BFL -6.370 SD4 / TTL 0.202 SL1 / TTL 0.119 SD4 / SL2 0.230 SD1 / f 0.301

[0067] Furthermore, the optical performance of the imaging lens 2 in the second embodiment also meets the requirements. Figure 4A It can be seen that the field curvature of the imaging lens 2 in the second embodiment is between 0mm and 0.2mm. Figure 4B It can be seen that the distortion of the imaging lens 2 in the second embodiment is between 0% and 0.2%. Figure 4C It can be seen that the modulation transfer function value of the imaging lens 2 in the second embodiment is between 0.50 and 1.0. Clearly, the field curvature and distortion of the imaging lens 2 in the second embodiment can be effectively corrected, and the lens resolution can meet the requirements, thus achieving better optical performance.

[0068] The third embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 5 The imaging lens 3 includes a first lens L31, an aperture ST3, a second lens L32, a third lens L33, a fourth lens L34, and a filter OF3. The first lens L31, aperture ST3, second lens L32, third lens L33, fourth lens L34, and filter OF3 are arranged sequentially along the optical axis OA3 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA3. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0069] The second lens L32 is a biconcave lens with its object side S34 being concave; the fourth lens L34 is a meniscus lens with negative refractive power, with its object side S38 being convex and its image side S39 being concave; the filter OF3 has its object side S310 and image side S311 both being planar; the combined focal length of the second lens L32, the third lens L33 and the fourth lens L34 is -13.9197mm; by utilizing the above-mentioned lens, aperture ST3 and the design that satisfies at least one of the conditions (1) to (7), the imaging lens 3 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0070] Table 7 is... Figure 5 The relevant parameter table of each lens in the imaging lens 3. When the refractive power, surface shape and conditions (1) to (7) of each lens in Table 7 are met, it is a preferred embodiment of the present invention.

[0071] Table 7

[0072]

[0073]

[0074] The definition of the aspherical surface concavity z of the aspherical lens in Table 7 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 8 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 7, where k is the conic constant and A to M are the aspherical coefficients.

[0075] Table 8

[0076]

[0077] Table 9 shows the relevant parameter values ​​of the imaging lens 3 in the third embodiment and the calculated values ​​of the corresponding conditions (1) to (7). As can be seen from Table 9, the imaging lens 3 in the third embodiment can meet the requirements of conditions (1) to (7).

[0078] Table 9

[0079] BFL 9.807mm SD1 5.000mm SD4 3.294mm SL1 1.870mm SL2 13.704mm R11 / R42 0.297 TTL / SD4 4.728 f4 / BFL -9.089 SD4 / TTL 0.212 SL1 / TTL 0.120 SD4 / SL2 0.240 SD1 / f 0.301

[0080] Furthermore, the optical performance of the imaging lens 3 in the third embodiment also meets the requirements. Figure 6A It can be seen that the field curvature of the imaging lens 3 in the third embodiment is between -0.2mm and 0.2mm. Figure 6B It can be seen that the distortion of the imaging lens 3 in the third embodiment is between -0.1% and 0.6%. Figure 6C It can be seen that the modulation transfer function value of the imaging lens 3 in the third embodiment is between 0.47 and 1.0. Clearly, the field curvature and distortion of the imaging lens 3 in the third embodiment can be effectively corrected, and the lens resolution can meet the requirements, thus achieving better optical performance.

[0081] The fourth embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 7 The imaging lens 4 includes a first lens L41, an aperture ST4, a second lens L42, a third lens L43, a fourth lens L44, and a filter OF4. The first lens L41, aperture ST4, second lens L42, third lens L43, fourth lens L44, and filter OF4 are arranged sequentially along the optical axis OA4 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA4. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0082] The second lens L42 is a biconcave lens with its object side S44 being concave; the fourth lens L44 is a meniscus lens with negative refractive power, with its object side S48 being convex and its image side S49 being concave; the filter OF4 has its object side S410 and image side S411 both being planar; by utilizing the above-mentioned lens, aperture ST4 and the design of satisfying at least one of conditions (1) to (2) and conditions (4) to (8), the imaging lens 4 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberration.

[0083] Table 10 is... Figure 7 The relevant parameter table of each lens of the imaging lens 4. When the refractive power and surface shape of each lens in Table 10 are met, and conditions (1) to (2) and (4) to (8) are satisfied, it is a preferred embodiment of the present invention.

[0084] Table 10

[0085]

[0086]

[0087] The definition of the aspherical surface concavity z of the aspherical lens in Table 10 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 11 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 10, where k is the conic constant and A to M are the aspherical coefficients.

[0088] Table 11

[0089]

[0090]

[0091] Table 12 shows the relevant parameter values ​​of the imaging lens 4 in the fourth embodiment and the calculated values ​​of the corresponding conditions (1) to (2) and conditions (4) to (8). As can be seen from Table 12, the imaging lens 4 in the fourth embodiment can meet the requirements of conditions (1) to (2) and conditions (4) to (8).

[0092] Table 12

[0093] BFL 11.330mm SD1 5.480mm SD4 4.023mm SL1 2.539mm SL2 15.874mm R11 / R42 0.530 TTL / SD4 4.577 |f4 / BFL| 51.925 SD4 / TTL 0.219 SL1 / TTL 0.138 SD4 / SL2 0.253 SD1 / f 0.288

[0094] Furthermore, the optical performance of the imaging lens 4 in the fourth embodiment also meets the requirements. Figure 8A It can be seen that the field curvature of the imaging lens 4 in the fourth embodiment is between -0.06mm and 0.1mm. Figure 8BIt can be seen that the distortion of the imaging lens 4 in the fourth embodiment is between 0% and 0.4%. Figure 8C It can be seen that the modulation conversion function value of the imaging lens 4 in the fourth embodiment is between 0.59 and 1.0. Clearly, the field curvature and distortion of the imaging lens 4 in the fourth embodiment can be effectively corrected, and the lens resolution can meet the requirements, thus achieving better optical performance.

[0095] The fifth embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 9 The imaging lens 5 includes a first lens L51, an aperture ST5, a second lens L52, a third lens L53, a fourth lens L54, and a filter OF5. The first lens L51, aperture ST5, second lens L52, third lens L53, fourth lens L54, and filter OF5 are arranged sequentially along the optical axis OA5 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA5. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0096] The second lens L52 is a biconcave lens with its object side S54 being concave; the fourth lens L54 is a meniscus lens with negative refractive power, with its object side S58 being convex and its image side S59 being concave; the filter OF5 has its object side S510 and image side S511 both being planar; by utilizing the above-mentioned lens, aperture ST5 and the design of satisfying at least one of conditions (1) to (2) and conditions (4) to (8), the imaging lens 5 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0097] Table 13 is... Figure 9 The relevant parameter table of each lens of the imaging lens 5. When the refractive power and surface shape of each lens in Table 13 are met, and conditions (1) to (2) and (4) to (8) are satisfied, it is a preferred embodiment of the present invention.

[0098] Table Thirteen

[0099]

[0100] The definition of the aspherical surface concavity z of the aspherical lens in Table 13 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 14 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 13, where k is the conic constant and A to M are the aspherical coefficients.

[0101] Table 14

[0102]

[0103]

[0104] Table 15 shows the relevant parameter values ​​of the imaging lens 5 in the fifth embodiment and the calculated values ​​of the corresponding conditions (1) to (2) and conditions (4) to (8). As can be seen from Table 15, the imaging lens 5 in the fifth embodiment meets the requirements of conditions (1) to (2) and conditions (4) to (8).

[0105] Table 15

[0106] BFL 10.767mm SD1 5.449mm SD4 4.180mm SL1 3.448mm SL2 14.571mm R11 / R42 0.229 TTL / SD4 4.310 |f4 / BFL| 19.925 SD4 / TTL 0.232 SL1 / TTL 0.191 SD4 / SL2 0.287 SD1 / f 0.287

[0107] In addition, the field curvature (illustration omitted) and distortion (illustration omitted) of the imaging lens 5 in the fifth embodiment can also be effectively corrected, and the image resolution can meet the requirements, thereby obtaining better optical performance.

[0108] The sixth embodiment of the imaging lens of the present invention will now be described in detail. Please refer to [link / reference]. Figure 10 The imaging lens 6 includes a first lens L61, an aperture ST6, a second lens L62, a third lens L63, a fourth lens L64, and a filter OF6. The first lens L61, aperture ST6, second lens L62, third lens L63, fourth lens L64, and filter OF6 are arranged sequentially along the optical axis OA6 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA6. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0109] The second lens L62 is a biconcave lens with its object side S64 being concave; the fourth lens L64 is a meniscus lens with positive refractive power, with its object side S68 being convex and its image side S69 being concave; the filter OF6 has its object side S610 and image side S611 both being planar; by utilizing the above-mentioned lens, aperture ST6 and the design of satisfying at least one of conditions (1) to (2) and conditions (4) to (8), the imaging lens 6 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0110] Table 16 is... Figure 10 The relevant parameter table of each lens of the imaging lens 6. When the refractive power and surface shape of each lens in Table 16 are met, and conditions (1) to (2) and conditions (4) to (8) are satisfied, it is a preferred embodiment of the present invention.

[0111] Table 16

[0112]

[0113] The definition of the aspherical surface concavity z of the aspherical lens in Table 16 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 17 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 16, where k is the conic constant and A to M are the aspherical coefficients.

[0114] Table 17

[0115]

[0116]

[0117] Table 18 shows the relevant parameter values ​​of the imaging lens 6 in the sixth embodiment and the calculated values ​​of the corresponding conditions (1) to (2) and conditions (4) to (8). As can be seen from Table 18, the imaging lens 6 in the sixth embodiment meets the requirements of conditions (1) to (2) and conditions (4) to (8).

[0118] Table 18

[0119] BFL 11.402mm SD1 5.420mm SD4 4.000mm SL1 2.428mm SL2 16.290mm R11 / R42 0.116 TTL / SD4 4.680 |f4 / BFL| 20.599 SD4 / TTL 0.214 SL1 / TTL 0.130 SD4 / SL2 0.246 SD1 / f 0.285

[0120] In addition, the field curvature (illustration omitted) and distortion (illustration omitted) of the imaging lens 6 in the sixth embodiment can also be effectively corrected, and the image resolution can meet the requirements, thereby obtaining better optical performance.

[0121] The seventh embodiment of the imaging lens of the present invention will now be described in detail. Please refer to... Figure 11 The imaging lens 7 includes a first lens L71, an aperture ST7, a second lens L72, a third lens L73, a fourth lens L74, and a filter OF7. The first lens L71, aperture ST7, second lens L72, third lens L73, fourth lens L74, and filter OF7 are arranged sequentially along the optical axis OA7 from the object side to the image side. During imaging, the light rays from the object side are finally imaged onto the imaging plane IMA7. According to paragraphs one to six of the [Detailed Embodiments], wherein:

[0122] The second lens L72 is a meniscus lens with a convex object side S74; the fourth lens L74 is a meniscus lens with negative refractive power, with a concave object side S78 and a convex image side S79; the filter OF7 has a flat object side S710 and an image side S711; by using the above-mentioned lens, aperture ST7 and the design that satisfies at least one of the conditions (1) to (7), the imaging lens 7 can effectively reduce the total length of the lens, effectively improve the resolution, effectively correct aberrations, and effectively correct chromatic aberrations.

[0123] Table 19 is... Figure 11The relevant parameter table of each lens in the imaging lens 7. When the refractive power, surface shape and conditions (1) to (8) of each lens in Table 19 are met, it is a preferred embodiment of the present invention.

[0124] Table 19

[0125]

[0126] The definition of the aspherical surface concavity z of the aspherical lens in Table 19 is the same as that in Table 1 of the first embodiment, and will not be repeated here. Table 20 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 19, where k is the conic constant and A to M are the aspherical coefficients.

[0127] Table 20

[0128]

[0129]

[0130] Table 21 shows the relevant parameter values ​​of the imaging lens 7 in the seventh embodiment and the calculated values ​​of the corresponding conditions (1) to (7). As can be seen from Table 21, the imaging lens 7 in the seventh embodiment can meet the requirements of conditions (1) to (7).

[0131] Table 21

[0132] BFL 9.988mm SD1 9.340mm SD4 8.426mm SL1 3.300mm SL2 14.190mm R11 / R42 -0.010 TTL / SD4 2.076 f4 / BFL -3.565 SD4 / TTL 0.482 SL1 / TTL 0.189 SD4 / SL2 0.594 SD1 / f 0.491

[0133] In addition, the field curvature (illustration omitted) and distortion (illustration omitted) of the imaging lens 7 in the seventh embodiment can also be effectively corrected, and the image resolution can also meet the requirements, thereby obtaining better optical performance.

[0134] The above embodiments, which use a glass lens and three plastic lenses, help to achieve thinness, maintain high resolution, and facilitate manufacturing processes.

[0135] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. An imaging lens, characterized in that, include: The first lens has positive refractive power. The first lens is a meniscus lens and includes a convex surface facing the object side and a concave surface facing the image side. The second lens has negative refractive power; The third lens has positive refractive power; and The fourth lens has refractive power; this fourth lens is a meniscus lens. The first lens, the second lens, the third lens, and the fourth lens are arranged sequentially along the optical axis from the object side to the image side; The imaging lens satisfies at least one of the following conditions: 0.1 ≤ SD1 / f ≤ 0.6; 19 ≤ |f4 / BFL| ≤ 52; Wherein, SD1 is the optically effective diameter of the first lens, f is the effective focal length of the imaging lens; wherein, f4 is the effective focal length of the fourth lens, and BFL is the distance from the image side of the fourth lens to the imaging surface along the optical axis.

2. The imaging lens as described in claim 1, characterized in that, The second lens includes a concave surface facing the image side, and the third lens is a biconvex lens, including a convex surface facing the object side and another convex surface facing the image side.

3. The imaging lens as described in claim 1, characterized in that, The fourth lens has positive refractive power.

4. The imaging lens as described in claim 1, characterized in that, The fourth lens has negative refractive power.

5. The imaging lens as described in any one of claims 1 to 4, characterized in that, The second lens includes a concave surface facing the object side, and the fourth lens includes a convex surface facing the object side and a concave surface facing the image side.

6. The imaging lens as described in claim 4, characterized in that, The second lens includes a convex surface facing the object side, and the fourth lens includes a concave surface facing the object side and a convex surface facing the image side.

7. The imaging lens as described in claim 1, characterized in that, When the second lens includes a convex surface facing the object side, the fourth lens includes a concave surface facing the object side and a convex surface facing the image side; when the second lens includes a concave surface facing the object side, the fourth lens includes a convex surface facing the object side and a concave surface facing the image side.

8. The imaging lens as described in claim 1, characterized in that, It also includes an aperture positioned between the first lens and the second lens.

9. The imaging lens as described in any one of claims 1-4 and 6-8, characterized in that, It further includes an aperture positioned between the first lens and the second lens, wherein the imaging lens satisfies at least one of the following conditions: 0 ≤ SD4 / TTL ≤ 0.5; 0.05 ≤ SL1 / TTL ≤ 0.5; 0.1 ≤ SD4 / SL2 ≤ 0.8; Wherein, TTL is the distance from the object side of the first lens to the imaging surface along the optical axis, SD4 is the optically effective diameter of the fourth lens, SL1 is the distance from the object side of the first lens to the aperture along the optical axis, and SL2 is the distance from the aperture to the imaging surface along the optical axis.

10. The imaging lens as described in any one of claims 1-4 and 6-8, characterized in that, The imaging lens meets at least one of the following conditions: -0.1 ≤ R11 / R42 ≤ 0.53; -10 ≤ f4 / BFL ≤ -3; 2 ≤ TTL / SD4 ≤ 7; Wherein, R11 is the radius of curvature of the object side of the first lens, R42 is the radius of curvature of the image side of the fourth lens; f4 is the effective focal length of the fourth lens, BFL is the distance from the image side of the fourth lens to the imaging surface along the optical axis; TTL is the distance from the object side of the first lens to the imaging surface along the optical axis, and SD4 is the optically effective diameter of the fourth lens.

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