TWI850786B - Imaging lens - Google Patents

Abstract

An imaging lens including a first lens group, a second lens group and an aperture is provided. The second lens group is disposed between the first lens group and the image minified side of the imaging lens. The second lens group essentially only includes three lens elements, and the diopter values of the three lens elements are positive, negative, and positive in sequence. The aperture is arranged between the first lens group and the second lens group, wherein the imaging lens includes a total of five or six lens elements with diopter, the lens elements include at least four aspherical lens elements and a spherical lens element, and the spherical lens elements are arranged on the second lens group. The field of view of the imaging lens is between 100 degrees and 165 degrees, and the lens surface closest to the image minified side of the imaging lens does not have an inflection point.

Description

Imaging lens

The present invention relates to an optical element, and in particular to an imaging lens.

With the advancement of modern video technology, imaging devices such as digital video cameras (DVC) and digital cameras (DC) have been widely used and applied in various fields. One of the core components of these imaging devices is the lens, which is used to clearly image the image on the screen or charge coupled device (CCD). In addition, in recent years, smart home surveillance cameras have been developing more and more vigorously, and people have higher and higher requirements for thinness and optical performance. To meet such requirements, the lens generally needs to have the characteristics of wide field of view, miniaturization, thinness, high resolution, large aperture, low distortion, day and night confocality, etc.

However, in general lenses, to achieve day and night confocality, a filter switching device must be used, or the number of lenses in the lens must be increased to achieve day and night confocality. However, no matter which method is used, the manufacturing cost will increase. In addition, in general lenses, multiple plastic lenses are used to reduce costs, but the use of multiple plastic lenses will have a larger thermal drift phenomenon, resulting in a decrease in optical quality. Therefore, how to make a lens with the above characteristics and provide good optical quality is one of the important topics for technicians in this field.

The present invention relates to an imaging lens having day-night confocal and good thermal drift performance.

The present invention provides an imaging lens, comprising a first lens group, a second lens group and an aperture. The second lens group is arranged between the first lens group and the image reduction side of the imaging lens. The second lens group substantially only includes three lenses, and the diopter values of the three lenses are positive, negative and positive in sequence. The aperture is arranged between the first lens group and the second lens group, wherein the imaging lens includes a total of five or six lenses with diopter, the lenses include at least four aspherical lenses and one spherical lens, and the spherical lens is arranged in the second lens group. The field of view of the imaging lens is between 100 degrees and 165 degrees, and the lens surface closest to the image reduction side of the imaging lens does not have an inflection point.

The present invention also provides an imaging lens, comprising a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens arranged in sequence, wherein the first lens is an aspherical lens with negative diopter. The second lens is an aspherical lens with diopter. The diopter values of the third lens, the fourth lens and the fifth lens are positive, negative and positive in sequence, and one of the lenses is a spherical lens, and the surface of the fifth lens facing the image reduction side of the imaging lens does not have an inflection point. The field of view angle of the imaging lens is between 100 degrees and 165 degrees.

Based on the above, in the embodiment of the present invention, the design of the lens meets the preset condition standards, so the lens of the embodiment of the present invention can achieve a wide field of view, miniaturization, day and night confocality and low thermal drift, and provide good optical imaging quality.

In order to make the above features and advantages of the present invention more clearly understood, embodiments are specifically cited below and described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a lens of an embodiment of the present invention. Referring to FIG. 1 , the lens 100 of the present embodiment includes a first lens group 110 and a second lens group 120. The first lens group 110 is located between the image magnification side OS and the image reduction side IS. The second lens group 120 is located between the first lens group 110 and the image reduction side IS. The first lens group 110 and the second lens group 120 are arranged along the optical axis A of the lens 100.

The lens 100 includes six or less lenses, and at least four of the six or less lenses are aspherical lenses. In this embodiment, the lens 100 includes six lenses, and five of them are aspherical lenses. In this way, phenomena such as spherical aberration, coma aberration, astigmatism, curvature of field, and distortion can be reduced, and the effect of high resolution can be achieved. In this embodiment, the first lens group 110 has a negative refractive power, and the second lens group 120 has a positive refractive power. In addition, in this embodiment, the lens 100 includes at least four plastic lenses and does not have a glue lens, and the second lens group 120 has at least one spherical lens.

In this embodiment, the first lens group 110 includes a first lens 112, a second lens 114, and a third lens 116 arranged in sequence from the image magnification side OS to the image reduction side IS, and the second lens group 120 includes a fourth lens 122, a fifth lens 124, and a sixth lens 126 arranged in sequence from the image magnification side OS to the image reduction side IS. Among them, the first lens 112, the second lens 114, the third lens 116, the fourth lens 122, and the fifth lens 124 are aspherical lenses. In this embodiment, the refractive powers of the first lens 112 to the sixth lens 126 are negative, negative, positive, positive, negative, and positive, respectively.

In this embodiment, the first lens 112 is a biconcave lens, the second lens 114 is a negative meniscus lens having a concave surface facing the image magnifying side OS, the third lens 116 is a positive meniscus lens having a convex surface facing the image magnifying side OS, the fourth lens 122 is a biconvex lens, the fifth lens 124 is a biconcave lens, and the sixth lens 126 is a biconvex lens.

In addition, in this embodiment, the lens 100 further includes an aperture stop S, a filter element 130, and a glass cover 140. The aperture stop S is disposed between the third lens 116 of the first lens group 110 and the fourth lens 122 of the second lens group 120. The filter element 130 is disposed between the sixth lens 126 of the second lens group 120 and the image reduction side IS. The glass cover 140 is disposed between the filter element 130 and the imaging surface 150 located at the image reduction side IS.

In this embodiment, the lens 100 meets the condition of 100 degrees ≦ FOV ≦ 165 degrees, where FOV is the field of view (FOV) of the lens 100, for example, the field of view in the diagonal direction of the imaging surface 150. In this way, the lens 100 that meets the above conditions can ensure its optical imaging quality and have good optical characteristics.

The following Table 1 lists the specific data of each lens in the lens 100 shown in FIG. 1. (Table 1) Surface number Radius of curvature (mm) Pitch (mm) Refractive Index Abbe number Mark S1 -20.4 1.1 1.53 55.4 112 S2 2.8 2.2 S3 -3.0 0.5 1.53 55.4 114 S4 -48.6 0.2 S5 5.7 2.3 1.66 20.4 116 S6 86.4 0.2 S7 Infinity 0.9 S S8 5.2 1.6 1.53 55.4 122 S9 -2.4 0.1 S10 -4.5 0.5 1.66 20.4 124 S11 10.0 0.2 S12 7.1 1.7 1.70 55.5 126 S13 -5.6 0.6 S14 Infinity 0.2 1.52 64.1 130 S15 Infinity 3.2 S16 Infinity 0.4 1.52 64.1 140 S17 Infinity 0.1 S18 Infinity 0.0 150

In Table 1, the spacing refers to the straight line distance between two adjacent surfaces along the optical axis A of the lens 100. For example, the spacing of surface S1 is the straight line distance between surface S1 and surface S2 and along the optical axis A. The thickness, refractive index and Abbe number corresponding to each lens in the annotation column must refer to the corresponding values of the spacing, refractive index and Abbe number in the same column. In addition, in Table 1, surface S1 and surface S2 are two surfaces of the first lens 112. Surface S3 and surface S4 are two surfaces of the second lens 114... and so on. Surface S7 is the aperture light bar S. Surface S14 and surface S15 are two surfaces of the filter element 130. Surface S16 and surface S17 are two surfaces of the glass cover 140. The surface S18 is the imaging surface 150 .

In the present embodiment, surfaces S1, S2, S3, S4, S5, S6, S8, S9, S10 and S11 of the lens 100 are aspherical surfaces and can be expressed by the following equation (1): (1)

In the equation, Z is the offset (sag) in the direction of the optical axis A, and c is the reciprocal of the radius of an osculating sphere, that is, the reciprocal of the radius of curvature close to the optical axis A (for example, the radius of curvature of surfaces S1, S2, S3, S4, S5, S6, S8, S9, S10 and S11 in Table 1). K is a cone coefficient (conic), r is an aspheric height, and A ₂ to A ₁₆ are aspheric coefficients. In this embodiment, coefficients K and A ₂ are both zero. The following Table 2 lists the aspheric parameter values of surfaces S1, S2, S3, S4, S5, S6, S8, S9, S10 and S11. (Table 2) A _{4 A6 A8} A ₁₀ A ₁₂ S1 4.2E-03 -1.8E-04 4.9E-06 -7.4E-08 5.0E-10 S2 -2.4E-03 -4.6E-05 2.0E-04 -2.9E-05 -1.2E-06 S3 4.3E-02 -8.3E-03 1.3E-03 -1.1E-04 4.7E-06 S4 6.6E-02 -1.8E-02 5.0E-03 -2.8E-05 -1.8E-04 S5 1.4E-02 -1.2E-02 6.3E-03 -1.2E-03 7.0E-06 S6 -2.3E-04 2.1E-03 0.0E+00 0.0E+00 0.0E+00 S8 -6.6E-03 2.0E-04 0.0E+00 0.0E+00 0.0E+00 S9 9.4E-03 3.0E-03 -1.1E-03 1.9E-04 0.0E+00 S10 1.1E-02 1.2E-03 -1.2E-03 1.6E-04 0.0E+00 S11 1.3E-02 -1.2E-03 -1.2E-04 2.4E-05 -3.2E-07

In the lens 100 of this embodiment, the total track length (TTL, the distance between S1 and S18 on the optical axis) of the lens is 15.9 mm. The effective focal length (EFL) is 2.00 mm. The aperture value (F-Number, Fno) is 2.0. The field of view FOV is 140 degrees.

FIG. 2 to FIG. 6 are imaging optical simulation data diagrams of the lens of FIG. 1. Please refer to FIG. 2 to FIG. 6, where FIG. 2 is a modulation transfer function (MTF) curve diagram of the lens 100 during the day, wherein the horizontal axis is the spatial frequency in cycles per millimeter (mm), and the vertical axis is the modulus of the optical transfer function (MTF). In this embodiment, the optical transfer function curve displayed by the lens 100 during the day is within the standard range, as shown in FIG. 2.

FIG3 is an optical transfer function curve of the lens 100 at night within an image height of 3.088 mm, wherein the horizontal axis is the spatial frequency and the vertical axis is the modulus of the optical transfer function. In this embodiment, the optical transfer function curve displayed by the lens 100 at night is within the standard range, as shown in FIG3. It can be verified that in this embodiment, the lens 100 can use fewer lenses and does not require additional actions to switch infrared filters, and does not require the use of glass-cemented optical elements to achieve day and night confocality and has good optical imaging quality during the day and at night.

FIG4 , FIG5 , and FIG6 are optical transfer function curves of the lens 100 at different image heights at temperatures of 20 degrees Celsius, -20 degrees Celsius, and 80 degrees Celsius, respectively. The horizontal axis represents the spatial frequency, and the vertical axis represents the modulus of the optical transfer function. T represents the curve in the meridional direction, S represents the curve in the sagittal direction, and the value after "TS" represents the image height. The curve in the meridional direction coincides with the curve in the sagittal direction when the image height is 0.0000 mm. In this embodiment, the modulus of the optical transfer function of the lens 100 is greater than 60% when the temperature is 20 degrees, the spatial frequency is 63 lp/mm, and the image height is 3.088 mm, the modulus of the optical transfer function is greater than 60% when the temperature is -20 degrees, the spatial frequency is 63 lp/mm, and the image height is 3.088 mm, and the modulus of the optical transfer function is greater than 60% when the temperature is -20 degrees, the spatial frequency is 63 lp/mm, and the image height is 3.088 mm, as shown in Figures 4 to 6. The lens 100 has good optical performance from -20 degrees to 80 degrees at a spatial frequency of 63 lp/mm. In other words, the lens 100 of the present embodiment has low thermal drift and good optical imaging quality when the temperature changes from -20 degrees Celsius to 80 degrees Celsius.

FIG7 is a schematic diagram of a lens of another embodiment of the present invention. Referring to FIG7 , the lens 200 of the present embodiment is similar to the lens 100 in FIG1 , and the difference between the two is that in the present embodiment, the second lens group 220 in the lens 200 includes a lens with an Abbe number greater than 70. Specifically, the Abbe number of the lens (i.e., the fourth lens 122) closest to the first lens group 210 in the second lens group 220 is greater than 70. In this way, the chromatic aberration of light from visible light to infrared light wavelengths can be effectively reduced and good optical properties can be obtained, and the lens 200 can achieve the effect that the focus position of infrared light and the focus position of visible light are substantially the same at the same time.

Specifically, the difference from the lens 100 in FIG. 1 is that in this embodiment, the first lens 212 is a negative meniscus lens having a convex surface facing the image magnifying side OS, the second lens 214 is a biconcave lens, and the third lens 216 is a biconvex lens. The first lens 212, the second lens 214, the third lens 216, the fifth lens 124, and the sixth lens 126 are aspherical lenses.

The following Table 3 lists the specific data of each lens in the lens 200 shown in FIG. 7. (Table 3) Surface number Radius of curvature (mm) Pitch (mm) Refractive Index Abbe number Mark S1 8.2 1.3 1.54 56.1 212 S2 1.4 2.7 S3 -4.6 0.5 1.54 56.1 214 S4 55.7 0.1 S5 8.3 2.4 1.66 20.4 216 S6 -6.0 0.3 S7 Infinity 0.3 S S8 6.6 1.3 1.44 95.1 122 S9 -2.8 0.1 S10 -9.3 0.5 1.66 20.4 124 S11 3.3 0.2 S12 3.6 2.2 1.54 56.1 126 S13 -3.2 0.9 S14 Infinity 0.2 1.52 64.1 130 S15 Infinity 2.7 S16 Infinity 0.4 1.52 64.1 140 S17 Infinity 0.1 S18 Infinity 0.0 150

The meanings of surfaces S1 to S18 recorded in the annotation column of Table 3, as well as the reference method of the distances, refractive indices and Abbe numbers recorded therein and the corresponding distances, refractive indices and Abbe numbers in the same column are the same as the reference method of Table 1 and will not be repeated here.

In this embodiment, surfaces S1, S2, S3, S4, S5, S6, S10, S11, S12, and S13 of the lens 200 are aspherical surfaces and can be expressed by the above equation (1). In this embodiment, coefficients _A2 and _A12 are zero. The following Table 4 lists the aspherical parameter values of surfaces S1, S2, S3, S4, S5, S6, S10, S11, S12, and S13. (Table 4) K A _{4 A6 A8} A ₁₀ S1 -3.7E+01 1.6E-04 4.4E-06 5.4E-09 0.0E+00 S2 -9.5E-01 -2.8E-03 2.5E-03 -2.3E-04 -1.4E-06 S3 -1.1E+01 -2.1E-02 5.9E-03 -6.0E-04 2.2E-05 S4 0.0E+00 -1.7E-02 1.2E-02 -2.0E-03 2.8E-04 S5 -8.3E+01 0.0E+00 0.0E+00 0.0E+00 0.0E+00 S6 -1.3E+00 0.0E+00 0.0E+00 0.0E+00 0.0E+00 S10 1.8E+01 -1.7E-02 3.0E-03 -5.6E-04 0.0E+00 S11 1.7E-01 -3.8E-02 1.0E-02 -1.8E-03 1.2E-04 S12 -3.0E-01 -2.8E-02 5.4E-03 -6.4E-04 3.0E-05 S13 -7.5E-01 -5.8E-05 -5.1E-04 3.3E-05 0.0E+00

In the lens 200 of this embodiment, the total length of the lens is 16.1 mm, the effective focal length is 1.85 mm, the aperture value is 2.0, and the field of view is 140 degrees.

FIG8 is a schematic diagram of a lens according to another embodiment of the present invention. Referring to FIG8 , the lens 300 of this embodiment is similar to the lens 200 of FIG7 , and the difference between the two is that the number of lenses in the first lens group 310 of the lens 300 is two, and the number of lenses in the second lens group 320 is three. Specifically, in this embodiment, the lens 300 includes five lenses.

Specifically, the difference from the lens 200 in FIG. 2 is that, in this embodiment, the first lens group 310 includes a first lens 212 and a second lens 314 arranged in sequence from the image magnification side OS to the image reduction side IS, and the second lens group 320 includes a third lens 322, a fourth lens 324 and a fifth lens 326 arranged in sequence from the image magnification side OS to the image reduction side IS.

In detail, in this embodiment, the second lens 314 is a positive meniscus lens having a concave surface facing the image magnifying side OS, the third lens 322 is a biconvex lens, the fourth lens 324 is a negative meniscus lens having a convex surface facing the image magnifying side OS, and the fifth lens 326 is a biconvex lens. Among them, the first lens 212, the second lens 314, the fourth lens 324 and the fifth lens 326 are aspherical lenses. In this embodiment, the refractive powers of the first lens 212 to the fifth lens 326 are negative, positive, positive, negative, and positive, respectively.

The following Table 5 lists the specific data of each lens in the lens 300 shown in FIG8. (Table 5) Surface number Radius of curvature (mm) Pitch (mm) Refractive Index Abbe number Mark S1 79.1 1.1 1.53 55.4 212 S2 1.6 2.2 S3 -10.5 2.7 1.66 20.4 314 S4 -4.6 1.2 S5 Infinity 0.7 S S6 5.6 1.5 1.44 95.1 322 S7 -3.3 0.1 S8 15.0 0.5 1.66 20.4 324 S9 2.5 0.3 S10 3.5 2.1 1.53 55.4 326 S11 -4.5 0.3 S12 Infinity 0.2 1.52 64.1 130 S13 Infinity 2.8 S14 Infinity 0.4 1.52 64.1 140 S15 Infinity 0.1 S16 Infinity 0.0 150

In Table 5, surface S5 is the aperture beam S. The meanings of surfaces S1 to S16 in the annotation column of Table 5, as well as the reference method of the distances, refractive indices and Abbe numbers recorded therein and the corresponding distances, refractive indices and Abbe numbers in the same column are the same as those in Table 1, and will not be repeated here.

In this embodiment, surfaces S1, S2, S3, S4, S8, S9, S10 and S11 of the lens 300 are aspherical surfaces and can be expressed by the above equation (1). In this embodiment, the coefficient _A2 is zero. The following Table 6 lists the aspherical parameter values of surfaces S1, S2, S3, S4, S8, S9, S10 and S11. (Table 6) K A _{4 A6} S1 4.1E+01 4.3E-04 2.5E-06 S2 -2.9E+00 6.2E-02 -1.3E-02 S3 -5.9E+00 -1.2E-02 1.4E-03 S4 1.8E+00 7.8E-04 1.1E-03 S8 0.0E+00 -3.1E-02 4.3E-03 S9 -1.5E-01 -4.7E-02 8.9E-03 S10 -1.2E+00 -1.5E-02 2.3E-03 S11 -6.8E-01 5.2E-04 -3.0E-04 _A8 A ₁₀ A ₁₂ S1 -6.0E-07 2.2E-08 -2.3E-10 S2 2.6E-03 -2.0E-04 0.0E+00 S3 -6.1E-04 1.3E-04 -8.9E-06 S4 -1.6E-04 2.3E-05 1.8E-06 S8 -4.7E-04 -1.7E-05 0.0E+00 S9 -1.6E-03 1.5E-04 -9.5E-06 S10 -2.1E-04 7.3E-06 1.4E-07 S11 1.2E-04 -2.5E-05 2.1E-06

In the lens 300 of the present embodiment, the total length of the lens is 16.1 mm. The effective focal length is 1.92 mm. The aperture value is 2.0. The field of view is 140 degrees. The lenses 200 and 300 are similar to the lens 100 in FIG. 1 , and can achieve good optical imaging quality during the day and night by using fewer lenses and without additional actions to switch infrared filters, and without using glass-cemented optical elements, that is, the lenses 200 and 300 can achieve day and night confocal. In addition, the lenses 200 and 300 also have low thermal drift and good optical imaging quality.

FIG9 is a flow chart of a method for manufacturing a lens according to an embodiment of the present invention. Referring to FIG9 , in this embodiment, the method for manufacturing a lens can be applied to at least the lens 100 of FIG1 , the lens 200 of FIG7 , or the lens 300 of FIG8 . The following description will be based on the lens 100 of FIG1 , but the present invention is not limited thereto. In the method for manufacturing a lens according to this embodiment, in step S900, a lens barrel is provided. In step S910, a first lens group 110 is placed and fixed in the lens barrel. In step S920, a second lens group 120 is placed and fixed in the lens barrel to complete the manufacture of the lens 100.

In summary, in the exemplary embodiments of the present invention, the design of the lens meets the preset condition standards, so the lens of the embodiment of the present invention can achieve a wide field of view, miniaturization, day and night confocality, and low thermal drift, and provide good optical imaging quality.

Although the present invention has been disclosed as above by the embodiments, they are not intended to limit the present invention. Any person with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be defined by the scope of the attached patent application.

100, 200, 300: lens 110, 210, 310: first lens group 112, 212: first lens 114, 214, 314: second lens 116, 216, 322: third lens 120, 220, 320: second lens group 122, 324: fourth lens 124, 326: fifth lens 126: sixth lens 130: filter element 140: glass cover 150: imaging surface A: optical axis OS: image magnification side IS: image reduction side S: aperture throttle S1~S18: surface

FIG. 1 is a schematic diagram of a lens of an embodiment of the present invention. FIG. 2 to FIG. 6 are imaging optical simulation data diagrams of the lens of FIG. 1. FIG. 7 is a schematic diagram of a lens of another embodiment of the present invention. FIG. 8 is a schematic diagram of a lens of another embodiment of the present invention. FIG. 9 is a flow chart of a method for manufacturing a lens of an embodiment of the present invention.

100: Lens

110: First lens group

112: First lens

114: Second lens

116: The third lens

120: Second lens group

122: The fourth lens

124: The fifth lens

126: The Sixth Lens

130: Filter element

140: Glass cover

150: Imaging surface

A: Optical axis

OS: Image magnification side

IS: Image zoom side

S: aperture aperture

S1~S18: Surface

Claims (11)

An imaging lens comprises: a first lens group; a second lens group disposed between the first lens group and the image reduction side of the imaging lens, the second lens group substantially only comprising three lenses, and the diopter values of the three lenses are positive, negative, and positive in sequence; and an aperture disposed between the first lens group and the second lens group, wherein the The imaging lens includes five or six lenses with refractive power in total, and the lenses include at least four aspherical lenses and one spherical lens, and the spherical lens is arranged in the second lens group, and the field of view angle of the imaging lens is between 100 degrees and 165 degrees, and the lens surface closest to the image reduction side of the imaging lens does not have an inflection point. The imaging lens as described in claim 1, wherein the first lens group includes a first lens, a second lens, and a third lens arranged in sequence from the image magnification side of the imaging lens to the image reduction side of the imaging lens, the second lens group includes a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the image magnification side of the imaging lens to the image reduction side of the imaging lens, and the fifth lens is an aspherical lens. The imaging lens as described in claim 2, wherein the imaging lens further satisfies one of the following conditions: (1) the refractive powers of the first lens to the sixth lens are negative, negative, positive, positive, negative, positive, respectively; (2) the first lens, the second lens, and the third lens are aspherical lenses. The imaging lens as described in claim 1, wherein the first lens group includes a first lens and a second lens, the second lens group includes a third lens, a fourth lens and a fifth lens arranged in sequence from the image magnification side of the imaging lens to the image reduction side of the imaging lens, wherein the fourth lens and the fifth lens are aspherical lenses. The imaging lens as described in claim 4, wherein the imaging lens further satisfies one of the following conditions: (1) the refractive powers of the first lens to the fifth lens are negative, positive, positive, negative, and positive, respectively; (2) the first lens and the second lens are aspherical lenses. An imaging lens comprises a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens arranged in sequence, wherein the first lens is an aspherical lens with negative diopter; the second lens is an aspherical lens with diopter; the diopter values of the third lens, the fourth lens and the fifth lens are positive, negative and positive in sequence, and one of the lenses is a spherical lens, and the surface of the fifth lens facing the image reduction side of the imaging lens does not have an inflection point; and the field of view angle of the imaging lens is between 100 degrees and 165 degrees. As in claim 6, the first lens and the second lens belong to a first lens group, and the third lens, the fourth lens and the fifth lens belong to a second lens group. An imaging lens as described in claim 1 or claim 7, wherein the first lens group has a negative refractive power and the second lens group has a positive refractive power. An imaging lens as described in any one of claim 1, claim 6 and claim 7, wherein the field of view of the imaging lens is between 140 degrees and 165 degrees. An imaging lens as described in any one of claim 1 and claim 7, wherein the imaging lens further satisfies one of the following conditions: (1) comprising at least four plastic lenses, and the imaging lens does not contain a glued lens; (2) the Abbe number of the lens in the second lens group closest to the first lens group is greater than 70. An imaging lens as described in any one of claim 1 and claim 7, wherein the imaging lens further comprises a filter element disposed between the second lens group and the image reduction side of the imaging lens.

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