Imaging lens and camera device

Abstract

The problem is to achieve weight reduction and cost reduction by including resin lenses, and to suppress the change in the field of view angle associated with changes in ambient temperature. The solution is to provide an imaging lens composed of n lenses, the n lenses including a first lens (L1) with a concave image side surface and a second lens (L2) with a concave object side surface, arranged in order from the object side, and an nth lens arranged closest to the image side, where 5≤n≤10, and when the object side of the aperture stop S is defined as the first group and the image side as the second group, the second group includes a lens Gp having a refractive index N corresponding to the d-line of N<1.68 and an Abbe number V corresponding to the d-line of 16<V<31, the lens arranged adjacent to the lens Gp is ​​a resin lens Lp, and the imaging lens satisfies the specified conditions. In addition, an imaging device equipped with the imaging lens is provided.

Description

Technical Field

[0001] The invention relates to an imaging lens and a camera device. Background Art

[0002] In recent years, various small imaging devices, such as digital cameras, that use solid-state imaging elements have become increasingly popular. The imaging optical systems of these small imaging devices are also being demanded to be further miniaturized, lightweight, and cost-effective. To achieve these reductions and lower costs, lenses for vehicles and drones (small drones, unmanned aerial vehicles), for example, are partially constructed using resin lenses.

[0003] For example, Example 3 of Patent Document 1 proposes an imaging lens that is composed of six resin lenses including negative, positive, negative, positive, and positive lenses in order from the object side and has a field angle of 100°.

[0004] Furthermore, Example 22 of Patent Document 2 proposes an imaging lens composed of six resin lenses, including negative, positive, positive, negative, positive, and positive lenses, in order from the object side, with a field of view of 98°. These imaging lenses achieve a wide field of view while maintaining high optical performance at room temperature.

[0005] Prior art literature

[0006] Patent Literature

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2018-136583

[0008] [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-65954 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] However, compared to room temperature (20°C), the imaging lens disclosed in Patent Document 1 exhibits a field of view fluctuation of -0.383° at 125°C and 0.158° at -20°, at an incident angle of 80°. Furthermore, the imaging lens disclosed in Patent Document 2 exhibits a field of view fluctuation of -0.390° at 125°C and 0.157° at -20°, at 80° at an incident angle of 80°. Thus, in these imaging lenses, field of view fluctuations associated with temperature changes are not sufficiently suppressed.

[0011] Therefore, an object of the present invention is to provide an imaging lens and an imaging device that can achieve weight reduction and cost reduction by including a resin lens and can suppress fluctuations in the angle of view associated with changes in ambient temperature.

[0012] Means for solving problems

[0013] To solve the above-mentioned problems, the imaging lens according to the present invention is characterized in that it is composed of n lenses, the n lenses including a first lens having a concave image-side surface and a second lens having a concave object-side surface, which are arranged in order from the object side, and an nth lens having positive refractive power and arranged closest to the image side, 6≤n≤10, an aperture stop is arranged between the first lens and the nth lens, and when the object side of the aperture is defined as the first group and the image side of the aperture is defined as the second group, the second group includes a lens Gp having a refractive index N corresponding to the d-line of N<1.68 and an Abbe number V corresponding to the d-line of 16<V<31, and a lens Lp arranged adjacent to the lens Gp is ​​a resin lens, and the imaging lens satisfies the following conditions:

[0014] -0.59<f / fp<-0.01·····(1)

[0015] in,

[0016] f: focal length of the imaging lens

[0017] fp: the combined focal length of the lens Gp and the lens Lp.

[0018] To solve the above-mentioned problems, the imaging lens according to the present invention is characterized in that it is composed of n lenses, the n lenses including a first lens having a concave image-side surface and a second lens having a concave object-side surface, arranged in order from the object side, and an n-th lens arranged closest to the image side, where n = 5; an aperture is arranged between the first lens and the n-th lens, and the lens group is defined as the first lens group, with the lens group closer to the object side than the aperture being the first lens group and the lens group closer to the image side than the aperture being the second lens group; the second lens group includes a lens Gp having a refractive index N corresponding to the d-line of N < 1.68 and an Abbe number V corresponding to the d-line of 16 < V < 31; the lens arranged adjacent to the lens Gp is ​​a resin lens Lp, and the imaging lens satisfies the following conditions:

[0019] -0.59<f / fp<-0.01·····(1)

[0020] in,

[0021] f: focal length of the imaging lens

[0022] fp: the combined focal length of the lens Gp and the lens Lp.

[0023] Furthermore, in order to solve the above-mentioned problems, an imaging device according to the present invention is characterized by including the above-mentioned imaging lens and an imaging element that converts an optical image formed by the imaging lens into an electrical signal.

[0024] Effects of the Invention

[0025] According to the present invention, by including a resin lens, weight reduction and cost reduction can be achieved, and fluctuations in the viewing angle due to changes in the ambient temperature can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a cross-sectional view of the imaging lens of Example 1.

[0027] Figure 2 These are aberration diagrams of the imaging lens of Example 1 in the infinity focus state.

[0028] Figure 3 This is a cross-sectional view of the imaging lens of Example 2.

[0029] Figure 4 These are aberration diagrams of the imaging lens of Example 2 in the infinity focus state.

[0030] Figure 5 This is a cross-sectional view of the imaging lens of Example 3.

[0031] Figure 6 These are aberration diagrams of the imaging lens of Example 3 in the infinity focus state.

[0032] Figure 7 is a cross-sectional view of an imaging lens of a reference example.

[0033] Figure 8 These are aberration diagrams of the reference imaging lens at infinity focus.

[0034] Figure 9 This is a cross-sectional view of the imaging lens of Example 5.

[0035] Figure 10 These are aberration diagrams of the imaging lens of Example 5 in the infinity focus state.

[0036] Figure 11 This is a cross-sectional view of the imaging lens of Example 6.

[0037] Figure 12 These are aberration diagrams of the imaging lens of Example 6 in the infinity focus state.

[0038] Figure 13 This is a cross-sectional view of the imaging lens of Example 7.

[0039] Figure 14 These are aberration diagrams of the imaging lens of Example 7 in the infinity focus state.

[0040] Figure 15 This is a cross-sectional view of the imaging lens of Example 8.

[0041] Figure 16These are aberration diagrams of the imaging lens of Example 8 in the infinity focus state.

[0042] Description of Reference Numerals

[0043] L1···First lens

[0044] L2···2nd lens

[0045] L3···The third lens

[0046] L4···4th lens

[0047] L5···5th lens

[0048] L6···6th lens

[0049] L7···7th lens

[0050] L8···8th lens

[0051] L9···9th lens

[0052] L10···10th lens

[0053] CG···Protective glass

[0054] IMG···Image surface

[0055] IRCF···Infrared Cut Filter DETAILED DESCRIPTION

[0056] The following describes an embodiment of an imaging lens and an imaging device according to the present invention. However, the imaging lens and imaging device described below represent one embodiment of the imaging lens and imaging device according to the present invention, and the imaging lens and imaging device according to the present invention are not limited to the following embodiment.

[0057] 1. Imaging lens

[0058] 1-1. Optical structure

[0059] The optical structure of this imaging lens will be described. This imaging lens is essentially composed of n lenses, including a first lens with a concave image-side surface and a second lens with a concave object-side surface, arranged in order from the object side, and an nth lens positioned closest to the image side, where 5≤n≤10. Here, "essentially composed of..." means that the optical elements that essentially constitute this imaging lens are the n lenses, namely the first through nth lenses, but additional optical elements other than lenses, such as lenses without substantial optical power, or apertures and cover glasses, are permitted. Furthermore, this imaging lens includes an aperture between the first and nth lenses. If the lens closer to the object side than the aperture is defined as the first group and the lens closer to the image side than the aperture is defined as the second group, the first group includes the first and second lenses, and the second group includes lenses Gp and Lp, described later, as well as the nth lens.

[0060] 1-1-1. Lens Structure

[0061] (1) First lens and second lens

[0062] By arranging a first lens with a concave image-side surface and a second lens with a concave object-side surface in this order on the object side of the imaging lens, a wide angle of view can be achieved while reducing the front lens diameter relative to the field of view. Here, "angular resolution" is defined as the number of pixels on the imaging element per 1-degree of the imaging field of view. By arranging the first and second lenses with the above-described surface shapes on the object side of the imaging lens, an imaging lens with higher angular resolution near the optical axis than at the periphery can be easily obtained. By improving the angular resolution near the optical axis compared to the periphery, objects near the optical axis can be imaged with high resolution, allowing for imaging of a wider range of the periphery. Therefore, if this imaging lens is used primarily as a sensor camera, such as for in-vehicle cameras or drone cameras, it can detect distant objects ahead of a moving object such as a vehicle or drone with high precision, and can identify objects surrounding the moving object (such as obstacles, traffic lights, and road signs) over a wide range. Furthermore, "near the optical axis" refers to the range within approximately 20% of the image height including the center of the optical axis, while "periphery" refers to the range outside approximately 70% of the image height including the center of the optical axis.

[0063] Furthermore, in lenses with a wide angle of view, the incident height (the distance from the optical axis) of the principal ray at the peripheral image height (e.g., image height 10°, image height 7°, etc.) is greatest in the first lens. Therefore, by making the image side of the first lens concave and increasing its curvature as described above, coma can be effectively corrected from near the center of the optical axis to the periphery, while also keeping distortion within an appropriate range at the periphery.

[0064] To achieve these functions and effects, the first lens preferably has a concave-convex configuration with the concave surface facing the image side. Furthermore, the second lens preferably has a concave-convex configuration with the concave surface facing the object side. Furthermore, it is preferable for the first lens to have negative refractive power in order to achieve a pre-negative optical configuration. Furthermore, when the first lens group consists of two lenses, the first and second lenses, the second lens preferably has positive refractive power.

[0065] (2) Lens Gp and Lens Lp

[0066] In this imaging lens, lens Gp is ​​a lens constituting the second group, whose refractive index N corresponding to the d-line satisfies N<1.68 and whose Abbe number V corresponding to the d-line satisfies 16<V<31.

[0067] Currently, the lens material that meets the above conditions is resin. In other words, lens Gp is ​​essentially a resin lens. Resin materials have a greater thermal expansion coefficient than glass materials. Therefore, if a resin lens is used to construct an imaging lens, the refractive index changes with changes in ambient temperature. In addition, the surface shape and lens thickness also change, resulting in fluctuations in the field of view angle and the focal position. However, in this imaging lens, by setting the surface shapes of the first and second lenses as described above and arranging lens Gp in the second group on the image side relative to the aperture, it is possible to suppress fluctuations in the incident height of the principal ray from lens Gp to the peripheral image height due to changes in ambient temperature. Therefore, the fluctuations in the incident height of the principal ray from lens Gp to the peripheral image height are small. Therefore, even if the refractive index, surface shape, etc. of lens Gp change due to ambient temperature, the impact of fluctuations in the field of view angle can be reduced, and fluctuations in the focal position can be suppressed.

[0068] In this imaging lens, the lens arranged adjacent to the lens Gp is ​​a resin lens Lp. As long as the lens Lp is a resin lens, it can be arranged on the object side of the lens Gp, on the image side of the lens Gp, or on both sides thereof. By arranging the lens Lp adjacent to the lens Gp and satisfying the conditional formula (1) described below, it is possible to suppress the change in the field angle over a wide temperature range. For example, vehicle-mounted lenses or drone lenses are mostly used outdoors, and in many cases are used from below freezing to high temperatures. By arranging the lens Lp adjacent to the lens Gp, for example, by appropriately adjusting the sign of the optical power of the two lenses, the surface shape, etc., it is easy to linearly offset the change in the field angle and the change in the focus position caused by the change in the ambient temperature. Therefore, it is possible to set at least two of the lenses constituting the imaging lens to be resin lenses (lens Gp, lens Lp), and realize an imaging lens in which the field angle change is small even if the ambient temperature changes. In terms of obtaining these effects, the lens Lp is more preferably arranged on the object side of the lens Gp.

[0069] By configuring lens Gp and lens Lp with optical powers of different signs, it is easier to linearly offset fluctuations in the field angle and focal position caused by changes in ambient temperature, which is also advantageous for correcting chromatic aberration. In this case, it is preferable for lens Gp to have negative optical power and lens Lp to have positive optical power, which effectively corrects chromatic aberration. Furthermore, it is more preferable for lens Gp to be a biconcave lens and lens Lp to be a biconvex lens. By configuring lens Gp and lens Lp as biconcave and biconvex lenses, respectively, it is possible to configure each lens with strong optical power while preventing excessive curvature of the lens surface, effectively correcting chromatic aberration and suppressing the occurrence of other aberrations.

[0070] Furthermore, the air gap between lens Gp and lens Lp is preferably smaller than the center thickness of lens Gp or lens Lp. Reducing the air gap between lens Gp and lens Lp can effectively shorten the total optical length of the imaging lens. Furthermore, a smaller air gap between lens Gp and lens Lp more effectively offsets field angle fluctuations and various aberrations. Therefore, by reducing this air gap, field angle fluctuations associated with changes in ambient temperature can be more effectively offset by appropriately configuring lens Gp and lens Lp with appropriate optical power, surface shape, and other factors.

[0071] Furthermore, lens Gp and lens Lp preferably abut against each other at the periphery (edge). By abutting lens Gp and lens Lp at the periphery, in addition to reducing the aforementioned air gap, the decentering error that is easily generated when shortening the total optical length can also be reduced compared to the case where the two lenses are arranged apart from each other. In addition, when the two lenses are arranged apart, if the air gap between the two lenses is made even smaller, it will be difficult to set the air gap with high precision when installing the lenses. On the other hand, if the two lenses are abutted at the periphery, decentering error or air gap error can be suppressed, reducing various manufacturing errors. Therefore, lenses with good optical performance can be manufactured with a high yield.

[0072] (3) nth lens

[0073] The nth lens is the lens positioned closest to the image side of the imaging lens. When n = 5, the positive or negative power of the nth lens is not particularly limited, but is preferably negative. On the other hand, when 6 ≤ n, the nth lens is configured to have positive power. When 6 ≤ n, configuring the nth lens with positive power can suppress vignetting, which is common when achieving a wide angle of view, and minimize the reduction in peripheral illumination.

[0074] The shape of the lens surface of the nth lens is not particularly limited. However, for example, by providing the image side of the nth lens with a curvature, when light incident on the imaging lens is reflected from the image plane and incident on the image side of the nth lens, the re-reflected light can be prevented from entering the image plane. In other words, by directing the re-reflected light to enter the outer side of the image plane, the occurrence of ghosting can be suppressed.

[0075] (4) Other lenses

[0076] When the imaging lens comprises five lenses (n=5), it is preferably composed of, in order from the object side, a first lens, a second lens, an aperture, a lens Lp, a lens Gp, and an nth lens. The order of the lenses Gp and Lp may be reversed.

[0077] When 6≤n≤10, the number of lenses other than the five lenses (the first lens, the second lens, the lens Lp, the lens Gp, and the nth lens) is not particularly limited, but it is preferred that at least one glass lens having substantial optical power be disposed on the object side and image side of each of the adjacent lenses Lp and Gp (or the lens Gp and the lens Lp). By disposing at least one glass lens on the object side of the resin lens Lp (or the resin lens Gp), the effects of heat or ultraviolet light on the resin lens from the object side can be suppressed. Furthermore, by disposing at least one glass lens on the image side of the resin lens Gp (or the resin lens Lp), the effects of heat (e.g., heat from an image sensor, etc.) or ultraviolet light (e.g., light reflected from the image plane) on the image side can be suppressed.

[0078] (5) Lenses before and after the aperture

[0079] The diaphragm here refers to the aperture stop that defines the beam diameter of the lens, that is, the aperture stop that defines the Fno of the lens. In this imaging lens, the object side of the diaphragm is the first group, and the image side of the diaphragm is the second group. The lens closest to the image side of the first group and the lens closest to the object side of the second group preferably have positive refractive power. By placing the diaphragm between the positive lenses, the distance between the lenses before and after the diaphragm can be minimized, shortening the total optical length. Furthermore, by placing the diaphragm between the positive lenses, the effective diameters of the lenses before and after the diaphragm can be reduced, effectively correcting aberrations that occur between the first and second groups.

[0080] 1-1-2. Group composition

[0081] The lens configuration of this imaging lens is as described above. The first lens group, the second lens group, and the aperture will be described in more detail below.

[0082] (1) Group 1

[0083] a) Constructing a lens

[0084] The first group preferably includes the first lens and the second lens, and is substantially composed of three or fewer lenses. By composing the first group of three or fewer lenses, the imaging lens can be easily miniaturized and lightweight.

[0085] b) Optical power

[0086] The first lens group preferably has negative refractive power as a whole. Providing negative refractive power to the first lens group allows for a pre-negative optical structure, making it easier to achieve a wide angle of view and reducing the front lens diameter relative to the angle of view.

[0087] c) Positive lens

[0088] When the first lens group has negative refractive power, it is preferable that the first lens group include at least one lens having positive refractive power. By configuring the first lens group, which generally has negative refractive power, to include a lens having positive refractive power, it is possible to effectively correct for curvature of field and chromatic aberration, thereby facilitating the realization of an imaging lens with high optical performance.

[0089] The lens closest to the image side in the first group preferably has positive refractive power. For example, if the first group consists of two lenses, the second lens preferably has positive refractive power. Furthermore, if the first group consists of three lenses, the third lens, positioned third from the object side, preferably has positive refractive power. Placing a lens with positive refractive power closest to the image side in the first group, i.e., adjacent to the object side of the aperture, effectively corrects distortion and astigmatism that may occur in the first lens, which is beneficial for achieving high resolution and wide angles at peripheral image heights.

[0090] When the lens positioned most image-side in the first group has positive refractive power, the Abbe number of this lens at the d-line is preferably less than 65. Furthermore, the Abbe number of this lens at the d-line is preferably greater than 23, and more preferably greater than 44. By placing a lens having such dispersion characteristics at the most image-side position in the first group, i.e., on the object side of the aperture stop, lateral chromatic aberration can be adequately corrected.

[0091] Furthermore, the image side of the lens disposed closest to the image side in the first group is preferably convex. This lens is disposed immediately before the aperture stop, so by making the image side of this lens convex, it is possible to control the angles of the axial light rays with the optical axis, as well as the angles of the peripheral light rays with the optical axis, thereby reducing these angles of light rays after passing through the lens immediately after the aperture stop. Consequently, the angles of these light rays incident on the resin lens disposed in the second group are also reduced, thereby suppressing changes in the field of view angle due to temperature changes. In this case, by disposing a lens having positive optical power closest to the object side in the second group and disposing lens Gp closer to the image side than this lens having positive optical power, it is possible to further reduce these angles of light rays relative to lens Gp and lens Lp, thereby suppressing changes in the field of view angle due to temperature changes.

[0092] d) Negative lens

[0093] When the first lens group has negative power, the first lens group includes at least one lens with negative power. Therefore, either the first lens or the second lens group preferably has negative power. In particular, by configuring the first lens group, which is positioned closest to the object side of the imaging lens, with negative power, it is easier to achieve a wide field of view, as described above, while also reducing the front lens diameter relative to the field of view. In this case, by including two lenses with negative power in the first lens group, the negative power configured for the first lens group can be distributed across the two lenses, making it easier to suppress spherical and chromatic aberrations that occur in the first lens group, thereby achieving an imaging lens with high optical performance.

[0094] It is preferable for at least one lens having negative power in the first group to have an Abbe number at the d-line greater than 38 in order to correct chromatic aberration. When the first group includes two lenses having negative power, the Abbe numbers at the d-line of these two lenses are preferably greater than 38, and more preferably greater than 44. Furthermore, when the first group includes two lenses having negative power, the Abbe number at the d-line of one of the lenses is more preferably greater than 50.

[0095] e) Aspheric lens

[0096] The diameter of the lenses making up the first group is larger than that of the lenses making up the second group. In wide-angle lenses, field curvature correction is often insufficient. Therefore, by also using an aspherical lens on the object side of the first group, and also using an aspherical lens on the image side of the first group, field curvature correction can be more effectively achieved.

[0097] (2) Group 2

[0098] a) Constructing a lens

[0099] The second group includes the aforementioned lens Gp and the nth lens. Lens Lp, positioned adjacent to lens Gp, may also be positioned in the first group, but is preferably positioned together with lens Gp in the second group. Furthermore, as mentioned above, it is preferred that lenses Gp and Lp, positioned adjacent to each other, each include at least one glass lens on their object and image sides. These glass lenses are also preferably positioned in the second group.

[0100] The object-side surface of the lens group closest to the object can be either convex or concave. A convex surface in the second group closest to the object can increase distortion at low image heights while minimizing the difference in angular resolution from the periphery. Conversely, a concave surface in the second group closest to the object can minimize distortion at low image heights while maintaining high angular resolution at the center of the image.

[0101] b) Optical power

[0102] The second lens group preferably has positive power overall. By configuring the first lens group with negative power and the second lens group with positive power, astigmatism occurring in the first lens group can be effectively corrected by the second lens group, achieving a wider field of view and a high-performance imaging lens.

[0103] c) Positive lens

[0104] If the second lens group has positive refractive power, it is preferable that the second lens group include at least two lenses with positive refractive power. This allows the second lens group to be configured with strong positive refractive power, effectively correcting astigmatism and other issues, while also suppressing excessive curvature of each lens surface. Furthermore, by including at least two lenses with positive refractive power, it is also possible to effectively correct curvature of field.

[0105] The lens closest to the object side in the second group, i.e., the lens immediately behind the aperture stop, preferably has positive refractive power. Placing a lens with strong positive refractive power closest to the object side in the second group achieves negative distortion, maintains high angular resolution near the optical axis, and achieves a wide field of view. In this case, by having a convex surface on the image side as the lens closest to the image side in the first group, fluctuations in the field of view and focus position can be effectively suppressed even when the ambient temperature changes, as described above.

[0106] Furthermore, in the lens positioned closest to the object in the second group, the difference between the angle of incidence of off-axis light and the angle of incidence of axial light is small. Therefore, in the lens positioned closest to the object in the second group, axial chromatic aberration can be corrected more effectively than off-axis chromatic aberration. Therefore, the positive-power lenses included in the second group are preferably low-dispersion. To effectively correct chromatic aberration, their Abbe numbers at the d-line are preferably greater than 53, and more preferably greater than 63.

[0107] Furthermore, as described above, when the n-th lens disposed most toward the image side in the second group satisfies 6≤n, the n-th lens has positive refractive power. Furthermore, it is preferable that lens Lp also has positive refractive power.

[0108] d) Negative lens

[0109] When the second lens group has positive refractive power, the second lens group preferably includes at least one lens with negative refractive power. By arranging at least one lens with negative refractive power in the second lens group having positive refractive power, chromatic aberration can be corrected well.

[0110] Furthermore, positioning the entrance pupil as close to the object side as possible is preferred for achieving radial miniaturization of the imaging lens. In the second group, by placing at least one lens with negative refractive power on the object side of a lens with positive refractive power, positioning the entrance pupil closer to the object side facilitates radial miniaturization.

[0111] Furthermore, if a lens having negative refractive power is arranged on the image side of a lens having positive refractive power in the second group, axial and near-axial chromatic aberrations can be corrected well.

[0112] In group 2, the refractive index of the lens having negative power at the d-line is preferably greater than 1.60, more preferably greater than 1.65. A larger refractive index of the lens having negative power is more preferable in order to achieve miniaturization of the imaging lens.

[0113] e) Resin lens

[0114] The second group includes lens Gp and lens Lp. Of the n lenses that comprise this imaging lens, all resin lenses are preferably arranged in the second group. By placing all resin lenses on the image side of the aperture stop, fluctuations in the field angle associated with changes in ambient temperature can be significantly suppressed, compared to placing resin lenses on the object side of the aperture stop. This also significantly reduces fluctuations in the focus position.

[0115] This imaging lens may also include resin lenses in addition to lens Gp and lens Lp, but it is more preferable that the two resin lenses among the n lenses comprising the imaging lens be lens Gp and lens Lp. By using only these two resin lenses, the number of optical elements that significantly affect fluctuations in the field of view angle and focus position when the ambient temperature changes does not increase significantly, making it easier to control these fluctuations. Furthermore, fluctuations in the field of view angle and focus position are more easily suppressed not only at temperatures significantly different from room temperature, such as 125°C or -20°C, but also within a temperature range of approximately ±20°C between room temperature and view angle. Furthermore, by using only these two resin lenses, fluctuations in the field of view angle, focus position, and various aberrations generated by the two lenses can be easily linearly offset by appropriately adjusting the optical power and surface shape of each lens. Furthermore, resin lenses yellow due to the effects of ultraviolet light and heat, reducing the transmittance of blue wavelength light, their complementary color. Yellowing is also caused by the effects of heat during molding, ultraviolet rays, aging, etc. To combat these aging effects, using two resin lenses can better correct chromatic aberration than using a single resin lens.

[0116] 1-2.Conditional expression

[0117] The imaging lens preferably adopts the above-mentioned configuration and satisfies at least one of the conditional expressions described below.

[0118] 1-2-1.Conditional expression (1)

[0119] -0.59<f / fp<-0.01·····(1)

[0120] in,

[0121] f: focal length of the imaging lens

[0122] fp: The combined focal length of lens Gp and lens Lp

[0123] Conditional formula (1) is a formula that specifies the ratio of the focal length of the imaging lens to the combined focal length of lens Gp and lens Lp. By satisfying conditional formula (1), the combined optical power of the resin lens is within an appropriate range, and the field angle change and focus position change caused by lens Lp can be used to offset the field angle change and focus position change caused by lens Gp, thereby reducing the field angle change and focus position change of the imaging lens associated with changes in ambient temperature. In addition, when conditional formula (1) is satisfied, the combined optical power of lens Gp and lens Lp shows a negative value. If the ambient temperature changes, field angle change and focus position change may occur not only due to the resin lens, but also due to the glass lens. At this time, by satisfying conditional expression (1), the field angle fluctuation and focus position fluctuation caused by the glass lens have opposite signs to those caused by the resin lens. Therefore, by canceling out these fluctuations, the field angle fluctuation, focus position fluctuation, and back focus fluctuation of the imaging lens associated with changes in ambient temperature can be suppressed. Furthermore, as described above, lens Gp is ​​preferably a biconcave lens, and lens Lp is preferably a biconvex lens. In this case, the curvature of the lens surface can be prevented from being excessively large, and a synthetic optical power within the range specified by conditional expression (1) can be obtained. Therefore, the field angle fluctuation, focus position fluctuation, and back focus fluctuation associated with changes in ambient temperature can be further reduced.

[0124] On the other hand, if the value of conditional expression (1) is greater than or equal to the upper limit, the fluctuation of the field angle, the fluctuation of the focus position, and the fluctuation of the back focus caused by the glass lens when the ambient temperature changes can be suppressed. On the other hand, if the value of conditional expression (1) is less than or equal to the lower limit, the combined optical power of lens Gp and lens Lp is too strong, and the fluctuation of the field angle and the fluctuation of the focus position caused by the resin lens when the ambient temperature changes becomes large. It is difficult to fully suppress the fluctuation of the field angle and the fluctuation of the focus position of the imaging lens accompanying the change of the ambient temperature, and therefore it is not preferable.

[0125] In terms of obtaining the above-mentioned effect, the lower limit value of conditional formula (1) is more preferably -0.55, further preferably -0.4, further preferably -0.3, and further preferably -0.25. In addition, the upper limit value of conditional formula (1) is more preferably -0.03, further preferably -0.05, and further preferably -0.07. In addition, when adopting these preferred lower limit values ​​or upper limit values, the inequality sign (≤) with the equal sign in conditional formula (1) can also be replaced with an inequality sign (<). The same principle applies to other conditional formulas.

[0126] 1-2-2.Conditional expression (2)

[0127] 0.1<ctGA / f<1.2·····(2)

[0128] in,

[0129] ctGA: The sum of the center thickness of lens Gp and the center thickness of lens Lp

[0130] Conditional equation (2) specifies the ratio of the sum of the center thickness of lens Gp and the center thickness of lens Lp to the focal length of the imaging lens. By satisfying conditional equation (2), the sum of the center thicknesses of lens Gp and lens Lp does not become excessively large, and when these lenses yellow due to ultraviolet light, heat, or the like, a decrease in the transmittance of blue light, their complementary color, can be suppressed.

[0131] In this case, it is preferred that the above-mentioned conditional expression (2) is satisfied, and that the center thickness of lens Gp is ​​thinner than the center thickness of lens Lp. As described above, lens Gp is ​​made of a resin material whose refractive index N and Abbe number V satisfy the prescribed conditions. The material of lens Gp is ​​more susceptible to yellowing. If yellowing occurs, a thin center thickness of lens Gp can further reduce the impact on transmittance and spectral characteristics, thereby maintaining good resolution performance over a long period of time.

[0132] On the other hand, if the value of conditional expression (2) is above the upper limit, the sum of the center thicknesses of lens Gp and lens Lp becomes too large, and the blue light transmittance decreases when these lenses are yellowed, making it difficult to correct chromatic aberration. On the other hand, if the value of conditional expression (2) is below the lower limit, the sum of the center thicknesses of lens Gp and lens Lp becomes too small, making it difficult to mold both lenses with high precision and obtaining the desired surface shape.

[0133] In order to obtain the above-mentioned effects, the lower limit of conditional expression (2) is preferably 0.30, more preferably 0.50, and still more preferably 0.55. The upper limit of conditional expression (2) is preferably 1.00, and more preferably 0.90.

[0134] 1-2-3.Conditional expression (3)

[0135] 0.9<fs / f<4.5·····(3)

[0136] in,

[0137] fs: Focal length of the lens adjacent to the image side of the aperture

[0138] The above-mentioned conditional equation (3) is an equation that specifies the ratio of the focal length of the lens arranged adjacent to the image side of the aperture to the focal length of the imaging lens. When conditional equation (3) is satisfied, the lens arranged adjacent to the image side of the aperture has a positive optical focal length of an appropriate size, which can reduce the angle of incidence of light on the lens Gp arranged adjacent to the image side of the aperture. Therefore, when the ambient temperature changes, the change in the angle of incidence of light on lens Gp is ​​small, which can suppress the change in the field of view angle. In addition, by satisfying conditional equation (3), negative distortion can be increased, thereby achieving a wide field of view angle while maintaining a high angular resolution near the optical axis.

[0139] On the other hand, if the value of conditional expression (3) is above the upper limit, the focal length of the lens adjacent to the image side of the aperture is too strong, the negative distortion is too large to exceed the appropriate range, and the imaging performance at the periphery is reduced. On the other hand, if the value of conditional expression (3) is below the lower limit, the focal length of the lens adjacent to the image side of the aperture is too small, and the effect of reducing the angle of incidence of light on lens Gp cannot be achieved, and the effect of suppressing the change in the field of view angle associated with changes in the ambient temperature is reduced.

[0140] In order to obtain the above-mentioned effects, the lower limit of conditional expression (3) is preferably 1.50, more preferably 1.80. The upper limit of conditional expression (3) is preferably 4.20, more preferably 4.00, further preferably 3.80, and further preferably 3.60.

[0141] 1-2-4.Conditional expression (4)

[0142] 1.8<f×tan(θ) / Yh<3.2·····(4)

[0143] in,

[0144] Yh: Maximum image height of the imaging lens

[0145] θ: half field of view angle of the imaging lens

[0146] Conditional equation (4) specifies the ratio of the ideal image height (f × tan(θ)) of the imaging lens to its maximum image height. Satisfying conditional equation (4) increases negative distortion, maintaining high angular resolution near the optical axis while achieving a wide field of view. In other words, the focal length of the imaging lens can be lengthened relative to the maximum image height.

[0147] In contrast, when the value of conditional expression (4) is above the upper limit, negative distortion is excessively large, making it difficult to maintain imaging performance in the periphery. On the other hand, when the value of conditional expression (4) is below the lower limit, it is difficult to maintain high angular resolution near the optical axis, making it difficult to achieve a focal length long enough to meet the maximum image height.

[0148] In order to obtain the above-mentioned effects, the lower limit of the conditional expression (4) is preferably 2.00, more preferably 2.10. The upper limit of the conditional expression (4) is preferably 3.00, more preferably 2.90, and even more preferably 2.80.

[0149] 1-2-4.Conditional expression (5)

[0150] 1.8<Ng1<2.0·····(5)

[0151] in,

[0152] Ng1: Refractive index of the first lens corresponding to the d-line

[0153] Conditional expression (5) specifies the refractive index of the first lens corresponding to the d-line. Satisfying conditional expression (5) allows the first lens, made of a high-refractive-index glass material, to be positioned closest to the object side of the imaging lens, thereby facilitating Petzval sum correction and achieving a wider angle of view.

[0154] In order to obtain the above-mentioned effect, the lower limit value of the conditional expression (5) is preferably 1.82, more preferably 1.84. The upper limit value of the conditional expression (5) is preferably 1.95, more preferably 1.90, and further preferably 1.88.

[0155] 1-2-6.Conditional expression (6)

[0156] 1.55<Ng2<1.89·····(6)

[0157] in,

[0158] Ng2: Refractive index of the second lens corresponding to the d-line

[0159] Conditional equation (6) specifies the refractive index of the second lens corresponding to the d-line. By satisfying conditional equation (6), the second lens, which is located second from the object side in the imaging lens, is made of low-refractive-index glass, making it easier to correct the Petzval sum.

[0160] In order to obtain the above-mentioned effect, the lower limit value of the conditional expression (6) is preferably 1.58, more preferably 1.60. The upper limit value of the conditional expression (6) is preferably 1.85, more preferably 1.80, and further preferably 1.79.

[0161] Furthermore, it is preferred that Ng1>Ng2, that is, the first lens is made of glass with a higher refractive index than the second lens. In this case, by providing the first lens with negative refractive power, the amount of high-refractive-index glass material used, which is more expensive than low-refractive-index glass material, can be reduced, thereby reducing the cost of the imaging lens and improving image quality.

[0162] 1-2-7.Conditional expression (7)

[0163] 0.01<Dpp / f<0.40·····(7)

[0164] in,

[0165] Dpp: The distance between lens Gp and lens Lp on the optical axis

[0166] The above-mentioned conditional expression (7) is an expression for specifying the ratio of the distance between lens Gp and lens Lp on the optical axis to the focal length of the imaging lens. In addition, the value of Dpp is always set to a positive value regardless of the arrangement order of lens Gp and lens Lp. By satisfying conditional expression (7), the incident height of the principal light in adjacent lenses Gp and lens Lp to each image height becomes lower. Even if the decentering sensitivity of the lens surfaces of the two lenses is different in size, since they are resin lenses, their balance is similar. Therefore, it is easy to linearly offset the field angle changes in the two lenses caused by changes in the ambient temperature, which can suppress the field angle changes of the imaging lens. In addition, by satisfying conditional expression (7), the distance between lens Gp and lens Lp can be properly maintained, so that the manufacturing error when assembling the lenses is within the tolerance range, and lenses with good optical performance can be manufactured with a high yield.

[0167] On the other hand, if the value of conditional expression (7) is above the upper limit, the spacing between lens Gp and lens Lp on the optical axis becomes larger, the incident height of the principal ray at each image height becomes higher, and the incident position of the principal ray is easily changed due to changes in the ambient temperature, making it difficult to fully suppress the fluctuation of the field angle of view of the imaging lens. On the other hand, if the value of conditional expression (7) is below the lower limit, the spacing between lens Gp and lens Lp on the optical axis is too small, and there is a possibility that the lens surfaces will collide with each other due to manufacturing tolerances of each lens, making it difficult to manufacture the imaging lens with a high yield.

[0168] In order to obtain the above-mentioned effects, the lower limit of conditional expression (7) is preferably 0.015, more preferably 0.020, and further preferably 0.025. The upper limit of conditional expression (7) is preferably 0.18, more preferably 0.16, further preferably 0.13, and further preferably 0.11.

[0169] 1-2-8.Conditional expression (8)

[0170] -0.3<Pair×f<0.3·····(8)

[0171] in,

[0172] Pair: The sum of the focal lengths of the object side and image side of the air lens formed between lens Gp and lens Lp, expressed as (1-n1) / r1-(1-n2) / r2

[0173] Here,

[0174] n1: The refractive index of the lens arranged on the object side among lens Gp and lens Lp corresponding to the d-line

[0175] n2: The refractive index of the lens arranged on the image side among lens Gp and lens Lp corresponding to the d-line

[0176] r1: The radius of curvature of the object side of the above-mentioned air lens

[0177] r2: The curvature radius of the image side of the air lens

[0178] Conditional equation (8) specifies the focal power of the air lens between lens Gp and lens Lp. If conditional equation (8) is satisfied, the focal power of the air lens decreases, the incident height of the principal rays of adjacent lenses Gp and Lp at each image height decreases, the principal rays have similar values, and the surface shape effects of the two lenses are set to the same degree. Therefore, fluctuations in the field of view angle of the two lenses caused by changes in ambient temperature are easily offset, and fluctuations in the field of view angle of the imaging lens can be suppressed.

[0179] In order to obtain the above-mentioned effects, the lower limit of conditional expression (8) is preferably -0.25, more preferably -0.20, and even more preferably -0.15. The upper limit of conditional expression (8) is preferably 0.25, more preferably 0.20, even more preferably 0.15, and even more preferably 0.10.

[0180] 1-2-9.Conditional expression (9)

[0181] -9.0<f1G / f<0.0·····(9)

[0182] in,

[0183] f1G: focal length of the first group

[0184] Conditional equation (9) specifies the ratio of the focal length of the first group to the focal length of the imaging lens. When conditional equation (9) is satisfied, the first group has negative refractive power. By configuring the first group with negative refractive power, large negative distortion is easily generated, maintaining high angular resolution near the optical axis and achieving a wide field of view.

[0185] On the other hand, if the value of conditional expression (9) is above the upper limit, it is difficult to generate large negative distortion, making it difficult to achieve a wide angle of view. On the other hand, if the value of conditional expression (9) is below the lower limit, the negative distortion is so large that it exceeds the appropriate range, making it difficult to obtain an imaging lens with high optical performance.

[0186] In order to achieve the above-mentioned effects, the lower limit of conditional expression (9) is preferably -8.50, more preferably -8.00, further preferably -7.50, further preferably -7.00, further preferably -6.00, further preferably -5.00, and most preferably -4.50. Furthermore, the upper limit of conditional expression (9) is preferably -0.50, more preferably -1.00, further preferably -1.50, and further preferably -2.00.

[0187] 1-2-10.Conditional expression (10)

[0188] 0.40<DD / LL<0.95·····(10)

[0189] in,

[0190] DD: The sum of the center thicknesses of the first to nth lenses

[0191] LL: The distance on the optical axis from the object side of the first lens to the image side of the nth lens

[0192] Conditional formula (10) is the ratio of the sum of the center thicknesses of the n lenses constituting the imaging lens to the distance on the optical axis from the object side of the first lens to the image side of the nth lens. The n lenses are held by a lens frame (lens barrel) or the like. If the ambient temperature changes significantly, the thickness of the lens or the like sometimes changes. In order to suppress the change in the field of view angle associated with the change in ambient temperature, it is necessary to keep each lens from tilting by the lens frame regardless of the ambient temperature. In order to suppress the tilting of the lens, there are methods of increasing the thickness of each lens and methods of pressing hard on the imaging lens from the most object side and the most image side. By satisfying the above-mentioned conditional formula (10), the center thickness of each lens and the force of pressing from both sides of the imaging lens can be set to a moderate range, and even if the ambient temperature changes, each lens is kept from tilting by the lens frame.

[0193] In order to obtain the above-mentioned effects, the lower limit of conditional expression (10) is preferably 0.45, more preferably 0.50, and even more preferably 0.52. Furthermore, the upper limit of conditional expression (10) is preferably 0.90, more preferably 0.85, even more preferably 0.82, even more preferably 0.75, even more preferably 0.70, even more preferably 0.68, and most preferably 0.60.

[0194] 1-2-11.Conditional expression (11)

[0195] 6.0<L / Yh<10.0·····(11)

[0196] in,

[0197] L: The total optical length of the imaging lens (the distance on the optical axis from the object-side lens surface of the first lens to the image surface)

[0198] Yh: Maximum image height of the imaging lens

[0199] Conditional equation (11) specifies the ratio of the total optical length of the imaging lens to the maximum image height. Satisfying conditional equation (11) allows for the configuration of appropriate optical power for the first lens group, generates negative distortion, maintains high angular resolution near the optical axis, and achieves a wide field of view.

[0200] In contrast, if the value of conditional expression (11) is below the lower limit, the optical power of the first group is too weak, making it difficult to generate negative distortion, and it is difficult to obtain an imaging lens with a wide field of view relative to the focal length. On the other hand, if the value of conditional expression (11) is above the upper limit, the optical power of the first group is too strong, and the imaging performance in the peripheral area is reduced. In addition, the diameter of the lenses constituting the first group increases, which is not preferable in terms of achieving miniaturization, weight reduction, and cost reduction of the imaging lens.

[0201] In order to obtain the above-mentioned effects, the lower limit of the conditional expression (11) is preferably 6.50, more preferably 7.00. The upper limit of the conditional expression (11) is preferably 9.00, more preferably 8.50, further preferably 8.20, and further preferably 8.05.

[0202] 1-2-12.Conditional expression (12)

[0203] -5.0<fL / f<4.0·····(12)

[0204] in,

[0205] fL: focal length of the nth lens

[0206] Conditional equation (12) specifies the ratio of the focal length of the nth lens disposed closest to the image side of the imaging lens to the focal length of the imaging lens. Satisfying conditional equation (12) suppresses the increase in the angle of incidence of light on the image plane, thereby appropriately maintaining the amount of peripheral light.

[0207] On the other hand, if the value of conditional expression (12) is above the upper limit, the back focus becomes too long, and the total optical length becomes longer, which is not preferable. On the other hand, if the value of conditional expression (12) is below the lower limit, the angle of incidence of light on the image plane becomes larger, so-called vignetting occurs, and the amount of peripheral light decreases, which is not preferable.

[0208] In order to obtain the above-mentioned effects, the lower limit of conditional expression (12) is preferably -4.70, more preferably -4.40, further preferably -4.20, further preferably -3.00, further preferably -2.00, and further preferably 0.00. Furthermore, the upper limit of conditional expression (12) is preferably 3.50, more preferably 3.00, further preferably 2.85, and further preferably 2.75.

[0209] The imaging lens described above achieves weight reduction and cost reduction by incorporating resin lenses, while suppressing fluctuations in the field of view angle and focus position associated with changes in ambient temperature. Furthermore, it generates negative distortion, maintains high angular resolution near the optical axis, and achieves an imaging lens with a wide field of view relative to its focal length.

[0210] 2. Camera

[0211] Next, the imaging device according to the present invention will be described. The imaging device according to the present invention is characterized by comprising the imaging lens according to the present invention described above, and an imaging element disposed on the image plane side of the imaging lens and configured to convert an optical image formed by the imaging lens into an electrical signal.

[0212] Here, the imaging element is not particularly limited; solid-state imaging elements such as CCD (Charge Coupled Device) sensors and CMOS (Complementary Metal Oxide Semiconductor) sensors can also be used. The imaging device of the present invention is suitable as an imaging device using a solid-state imaging element. Furthermore, the imaging device can obviously be a fixed-lens imaging device in which the lens is fixed to the housing, or an interchangeable-lens imaging device such as a single-lens reflex camera or a mirrorless single-lens camera.

[0213] The imaging device of the present invention preferably includes an image processing unit that electrically processes image data acquired by the imaging element to change the shape of the captured image, and an image correction data storage unit that stores image correction data, an image correction program, and the like used to process the captured image data in the image processing unit. When miniaturizing the lens, distortion or lateral chromatic aberration is more likely to occur. In this case, it is preferable that the image correction data storage unit pre-store data for correcting distortion or lateral chromatic aberration, and the image processing unit use this data to correct distortion or lateral chromatic aberration. With such an imaging device, further miniaturization of the lens can be achieved, resulting in beautiful captured images and a more compact imaging device.

[0214] In the above-mentioned imaging lens, the angular resolution near the optical axis is high, and a wide field of view compared to the focal length can be achieved. Therefore, by applying this camera device to vehicle-mounted lenses, drone lenses, etc., especially sensor cameras, it is possible to detect distant objects in front of the direction of travel of mobile bodies such as vehicles and drones with high precision, and to identify objects around the mobile body (obstacles, traffic lights, road traffic signs, etc.) over a wide range.

[0215] Next, the present invention will be described in detail with reference to Examples. However, the present invention is not limited to the following Examples.

[0216] [Example 1]

[0217] (1) Optical structure

[0218] Figure 1 This is a cross-sectional view of the imaging lens of Example 1 according to the present invention, when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative refractive power, a second lens L2 with positive refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, and a sixth lens L6 with positive refractive power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is arranged on the image side of the second lens L2.

[0219] In this imaging lens, the first lens group is composed of the first lens L1 and the second lens L2, and the second lens group is composed of the third lens L3 through the sixth lens L6. The first lens L1 is a negative meniscus lens with its concave surface facing the image side, the second lens L2 is a positive meniscus lens with its concave surface facing the object side, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconvex lens, the fifth lens L5 is a biconcave lens, and the sixth lens L6 is a biconvex lens. The fifth lens L5 is referred to as lens Gp in the present invention, and the fourth lens L4 is referred to as lens Lp in the present invention. The nth lens is the sixth lens L6. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0220] also, Figure 1 The term "IMG" shown here represents the image plane, specifically the imaging plane of a solid-state imaging element such as a CCD sensor or CMOS sensor, or the film surface of a silver halide film. Furthermore, a parallel flat plate having no substantial optical power, such as a cover glass CG, is provided on the object side of the imaging plane IMG. These points are the same as those in the lens cross-sectional views shown in other embodiments, and therefore their explanation is omitted below.

[0221] (2) Numerical Example

[0222] Next, we will describe numerical examples applying specific numerical values ​​to this lens. The following sections list "Lens Data," "Various Specification Values," "Variable Intervals," "Aspheric Coefficients," and "Focal Lengths of Each Lens." The values ​​for each conditional expression (Table 1) and the values ​​used in each conditional expression (Table 2) are summarized after Example 8. The field angle variation range for this example is also summarized after Example 8.

[0223] In the lens data, "Surface Number" indicates the lens surface number, counted from the object side. "r" indicates the radius of curvature of the lens surface. "d" indicates the distance between the lens surfaces on the optical axis. "Nd" indicates the refractive index corresponding to the d-line (wavelength λ = 587.6nm). "vd" indicates the Abbe number corresponding to the d-line. In addition, the "*" displayed in the column after "Surface Number" indicates that the lens surface is aspherical, and "S" indicates the aperture stop. In addition, the unit of length in each table is "mm", and the unit of field of view is "°". In addition, "INF" for the radius of curvature indicates a flat surface.

[0224] In various specification values, "f" represents the focal length of the lens, "Fno" represents the F value, and "θ" represents the half field of view angle.

[0225] The aspheric coefficient is a value when the aspheric shape is defined by the following formula.

[0226] (Y)=CY 2 / [1+{1-(1+k)·C 2 Y 2} 1 / 2 ]+A4·Y 4 +A6·Y 6 +A8·Y 8 +A10·Y 10 +A12·Y 12 +A14·Y 14

[0227] Among them, “E±XX” performance index mark means “×10 ±XX In the above formula, “C” is the curvature at the vertex of the surface, “Y” is the height relative to the optical axis in the direction perpendicular to the optical axis, “k” is the cone coefficient, and “An” is the n-th order aspheric coefficient.

[0228] The focal length of each lens indicates the focal length of each lens from the first lens to the nth lens (the sixth lens in this embodiment) constituting the imaging lens.

[0229] The items in the above-mentioned tables are the same as those in the tables shown in other embodiments, and therefore their description is omitted below.

[0230] (Lens data)

[0231] Face number r d Nd vd 1* 29.432 1.300 1.85135 40.10 2* 4.370 2.502 3 -9.778 5.300 1.74400 44.90 4 -9.322 0.200 5S 0.000 1.748 6* 11.422 6.300 1.49700 81.61 7* -8.167 3.000 8* 10.066 2.354 1.54472 55.86 9* -10.163 0.200 10* -15.768 0.933 1.63980 23.27 11* 5.024 1.680 12 8.000 3.536 1.49700 81.61 13 -17.589 0.400 14 0.000 0.400 1.51680 64.20 15 0.000 0.700 16 0.000 0.500 1.51680 64.20 17 0.000 1.440

[0232] (various specifications)

[0233] f 5.001 Fno 1.640 θ 66.000

[0234] (Aspheric coefficient)

[0235]

[0236]

[0237] (Focal length of each lens)

[0238] focal length First lens -6.175 Second lens 45.090 The third lens 10.727 The fourth lens 9.681 5th lens -5.853 6th lens 11.596

[0239] In addition, Figure 2 The longitudinal aberration diagram of the imaging lens when focusing on an object at infinity is shown in the figure. The longitudinal aberration diagrams shown in each figure are spherical aberration (mm), astigmatism (mm), and distortion (%), starting from the left side of the figure. In the diagram showing spherical aberration, the vertical axis is the ratio to the open F value, the horizontal axis is defocus, the solid line shows the spherical aberration at the d-line (wavelength λ = 587.6nm), the dashed line shows the spherical aberration at the g-line (wavelength λ = 435.8nm), and the dotted line shows the spherical aberration at the C-line (wavelength λ = 656.3nm). In the diagram showing astigmatism, the vertical axis is the half field angle (θ), the horizontal axis is defocus, the solid line shows the sagittal image plane (X) corresponding to the d-line, and the dotted line shows the meridional image plane (Y) corresponding to the d-line. In the diagram showing distortion aberration, the vertical axis is the half field angle (θ), and the horizontal axis is %, showing distortion aberration. Matters related to these longitudinal aberration diagrams are the same as those in the longitudinal aberration diagrams shown in other embodiments, so the description is omitted below.

[0240] [Example 2]

[0241] (1) Optical structure

[0242] Figure 3 This is a cross-sectional view of the imaging lens of Example 2 of the present invention, when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with positive optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with negative optical power, and a sixth lens L6 with positive optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is positioned on the image side of the second lens L2. Furthermore, an infrared cut filter IRCF is positioned on the image side of the sixth lens L6.

[0243] In this imaging lens, the first lens group is composed of the first lens L1 and the second lens L2, and the second lens group is composed of the third lens L3 through the sixth lens L6. The first lens L1 is a negative meniscus lens with its concave surface facing the image side, the second lens L2 is a positive meniscus lens with its concave surface facing the object side, and the third lens L3 is a positive meniscus lens with its concave surface facing the object side. The fourth lens L4 is a biconvex lens, the fifth lens L5 is a biconcave lens, and the sixth lens L6 is a biconvex lens. The fifth lens L5 is referred to as lens Gp in the present invention, and the fourth lens L4 is referred to as lens Lp in the present invention. The nth lens is the sixth lens L6. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0244] (2) Numerical Example

[0245] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 4 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0246] (Lens data)

[0247]

[0248]

[0249] (various specifications)

[0250] F 4.405 Fno 1.605 θ 66.000

[0251] (Aspheric coefficient)

[0252]

[0253]

[0254] (Focal length of each lens)

[0255]

[0256]

[0257] [Example 3]

[0258] (1) Optical structure

[0259] Figure 5This is a cross-sectional view of the imaging lens of Example 3 of the present invention, when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with positive optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with negative optical power, and a sixth lens L6 with positive optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is positioned on the image side of the second lens L2. Furthermore, an infrared cut filter IRCF is positioned on the image side of the sixth lens L6.

[0260] In this imaging lens, the first lens group is composed of the first lens L1 and the second lens L2, and the second lens group is composed of the third lens L3 through the sixth lens L6. The first lens L1 is a negative meniscus lens with its concave surface facing the image side, the second lens L2 is a positive meniscus lens with its concave surface facing the object side, and the third lens L3 is a positive meniscus lens with its concave surface facing the object side. The fourth lens L4 is a biconvex lens, the fifth lens L5 is a biconcave lens, and the sixth lens L6 is a biconvex lens. The fifth lens L5 is referred to as lens Gp in the present invention, and the fourth lens L4 is referred to as lens Lp in the present invention. The nth lens is the sixth lens L6. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0261] (2) Numerical Example

[0262] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 6 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0263] (Lens data)

[0264]

[0265]

[0266] (various specifications)

[0267] F 5.025 Fno 1.460 θ 66.000

[0268] (Aspheric coefficient)

[0269]

[0270]

[0271]

[0272] (Focal length of each lens)

[0273] focal length First lens -10.574 Second lens 51.497 The third lens 13.273 The fourth lens 7.558 5th lens -5.300 6th lens 12.462

[0274] [Reference example]

[0275] (1) Optical structure

[0276] Figure 7 This is a cross-sectional view of the imaging lens of a reference example according to the present invention, when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with positive optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, and a fifth lens L5 with negative optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is positioned on the image side of the second lens L2. Furthermore, an infrared cut filter IRCF is positioned on the image side of the fifth lens L5.

[0277] In this imaging lens, the first lens group is composed of the first lens L1 and the second lens L2, while the second lens group is composed of the third lens L3 through the fifth lens L5. The first lens L1 is a negative meniscus lens with its concave surface facing the image side, the second lens L2 is a positive meniscus lens with its concave surface facing the object side, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconvex lens, and the fifth lens L5 is a biconcave lens. The fifth lens L5 is referred to as lens Gp in the present invention, and the fourth lens L4 is referred to as lens Lp in the present invention. Furthermore, the nth lens is the fifth lens L5. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0278] (2) Numerical Example

[0279] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 8 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0280] (Lens data)

[0281]

[0282]

[0283] (various specifications)

[0284] F 5.000 Fno 1.640 θ 61.500

[0285] (Aspheric coefficient)

[0286]

[0287]

[0288]

[0289] (Focal length of each lens)

[0290] focal length First lens -11.294 Second lens 39.426 The third lens 10.392 The fourth lens 8.687 5th lens -5.877

[0291] [Example 5]

[0292] (1) Optical structure

[0293] Figure 9 This is a cross-sectional view of the imaging lens of Example 5 of the present invention when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with positive optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with positive optical power, a sixth lens L6 with negative optical power, and a seventh lens L7 with positive optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is positioned on the image side of the second lens L2. Furthermore, an infrared cut filter IRCF is positioned on the image side of the seventh lens L7.

[0294] In this imaging lens, the first lens group consists of the first lens L1 and the second lens L2, while the second lens group consists of the third lens L3 through the seventh lens L7. The first lens L1 is a negative meniscus lens with its concave surface facing the image side. The second lens L2 is a positive meniscus lens with its concave surface facing the object side. The third lens L3 is a biconvex lens. The fourth lens L4 is a positive meniscus lens with its concave surface facing the object side. The fifth lens L5 is a biconvex lens. The sixth lens L6 is a biconcave lens. The seventh lens L7 is a biconvex lens. The sixth lens L6 is referred to as lens Gp in the present invention, and the fifth lens L5 is referred to as lens Lp in the present invention. The nth lens is the seventh lens L7. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0295] (2) Numerical Example

[0296] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 10 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0297] (Lens data)

[0298] Face number r d Nd vd 1* 22.732 1.300 1.85945 40.10 2* 4.749 2.520 3 -7.495 5.169 1.75035 44.72 4 -9.458 0.200 5S 0.000 0.803 6* 9.911 6.071 1.58687 59.46 7* -14.786 0.200 8 -17.201 3.404 1.49932 81.61 9 -10.737 0.518 10* 9.813 2.627 1.54845 55.86 11* -7.847 0.200 12* -11.487 1.000 1.65011 23.27 13* 5.050 1.576 14 6.982 4.812 1.55310 75.52 15 -134.681 0.400 16 0.000 0.400 1.51986 64.20 17 0.000 0.900 18 0.000 0.500 1.51986 64.20 19 0.000 0.300

[0299] (various specifications)

[0300] F 5.000 Fno 1.640 θ 63.00

[0301] (Aspheric coefficient)

[0302]

[0303]

[0304]

[0305] (Focal length of each lens)

[0306] focal length First lens -7.226 Second lens 372.616 The third lens 11.122 The fourth lens 48.700 5th lens 8.392 6th lens -5.270 7th lens 12.148

[0307] [Example 6]

[0308] (1) Optical structure

[0309] Figure 11 This is a cross-sectional view of the imaging lens of Example 6 of the present invention when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with positive optical power, a sixth lens L6 with positive optical power, a seventh lens L7 with negative optical power, and an eighth lens L8 with positive optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is arranged on the image side of the third lens L3. Furthermore, an infrared cut filter IRCF is arranged on the image side of the eighth lens L8.

[0310] In this imaging lens, the first group consists of lenses L1 through L3, while the second group consists of lenses L4 through L8. Lens L1 is a negative meniscus lens with its concave surface facing the image side. Lens L2 is a biconcave lens. Lens L3 is a positive meniscus lens with its concave surface facing the object side. Lens L4 is a biconvex lens. Lens L5 is a positive meniscus lens with its concave surface facing the object side. Lens L6 is a biconvex lens. Lens L7 is a biconcave lens. Lens L8 is a biconvex lens. Lens L7 is a Gp lens, and Lens L6 is Lp. Lens L8 is the nth lens. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0311] (2) Numerical Example

[0312] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 12 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0313] (Lens data)

[0314] Face number r d Nd vd 1* 19.986 1.300 1.85945 40.10 2* 5.919 2.478 3 -8.778 0.600 1.62708 58.12 4 105.358 0.804 5 -17.786 5.172 1.74906 49.22 6 -9.714 0.200 7S 0.000 0.358 8* 9.205 3.018 1.55626 71.70 9* -37.707 2.049 10 -46.628 4.500 1.62172 63.39 11 -15.055 0.200 12* 8.276 2.492 1.54845 55.86 13* -7.997 0.263 14* -8.514 0.936 1.65011 23.27 15* 5.786 1.525 16 7.452 0.900 1.62172 63.39 17 -100.000 0.400 18 0.000 0.400 1.51986 64.20 19 0.000 0.700 20 0.000 0.500 1.51986 64.20 21 0.000 1.015

[0315] (various specifications)

[0316] F 5.000 Fno 1.640 θ 63.000

[0317] (Aspheric coefficient)

[0318]

[0319]

[0320] (Focal length of each lens)

[0321]

[0322]

[0323] [Example 7]

[0324] (1) Optical structure

[0325] Figure 13 This is a cross-sectional view of the imaging lens of Example 7 of the present invention when focusing at infinity. This imaging lens consists of, arranged in order from the object side, a first lens L1 with negative optical power, a second lens L2 with negative optical power, a third lens L3 with positive optical power, a fourth lens L4 with positive optical power, a fifth lens L5 with negative optical power, a sixth lens L6 with positive optical power, a seventh lens L7 with positive optical power, an eighth lens L8 with negative optical power, and a ninth lens L9 with positive optical power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is positioned on the image side of the third lens L3. Furthermore, an infrared cut filter IRCF is positioned on the image side of the ninth lens L9.

[0326] In this imaging lens, the first group consists of the first lens L1 through the third lens L3, and the second group consists of the fourth lens L4 through the ninth lens L9. The first lens L1 is a negative meniscus lens with its concave surface facing the image side. The second lens L2 is a biconcave lens, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconvex lens, and the fifth lens L5 is a negative meniscus lens with its concave surface facing the image side. The sixth lens L6 is a biconvex lens, the seventh lens L7 is a biconvex lens, the eighth lens L8 is a biconcave lens, and the ninth lens L9 is a biconvex lens. The eighth lens L8 is referred to as lens Gp in the present invention, and the seventh lens L7 is referred to as lens Lp in the present invention. The nth lens is the ninth lens L9. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0327] (2) Numerical Example

[0328] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 14 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0329] (Lens data)

[0330]

[0331]

[0332] (various specifications)

[0333] F 5.001 Fno 1.640 θ 63.000

[0334] (Aspheric coefficient)

[0335]

[0336] Face number A12 A14 1 9.36771E-09 -1.01629E-10 2 -6.18819E-07 2.17766E-08 8 5.28288E-08 -1.08234E-09 9 1.03609E-08 -1.99251E-10 14 -3.48786E-08 6.64742E-10 15 1.41934E-07 -1.66528E-09 16 1.13727E-07 -1.56079E-09 17 -9.57011E-08 1.33647E-09

[0337] (Focal length of each lens)

[0338] focal length First lens -10.633 Second lens -7.127 The third lens 9.897 The fourth lens 11.082 5th lens -12.736 6th lens 16.744 7th lens 10.162 8th lens -6.977 9th lens 11.249

[0339] [Example 8]

[0340] (1) Optical structure

[0341] Figure 15This is a cross-sectional view of the imaging lens of Example 8 according to the present invention, when focusing at infinity. This imaging lens comprises, arranged in order from the object side, a first lens L1 with negative refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, a sixth lens L6 with positive refractive power, a seventh lens L7 with positive refractive power, an eighth lens L8 with negative refractive power, a ninth lens L9 with positive refractive power, and a tenth lens L10 with negative refractive power. When focusing from an object at infinity to an object at close range, all lenses move along the optical axis toward the object side. An aperture stop S is arranged on the image side of the third lens L3. Furthermore, an infrared cut filter IRCF is arranged on the image side of the tenth lens L10.

[0342] In this imaging lens, the first group consists of the first lens L1 to the third lens L3, and the second group consists of the fourth lens L4 to the tenth lens L10. The first lens L1 is a negative meniscus lens with its concave surface facing the image side. The second lens L2 is a biconcave lens, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconvex lens, the fifth lens L5 is a biconcave lens, the sixth lens L6 is a biconvex lens, the seventh lens L7 is a biconvex lens, the eighth lens L8 is a biconcave lens, the ninth lens L9 is a biconvex lens, and the tenth lens L10 is a negative meniscus lens with its concave surface facing the object side. The eighth lens L8 is referred to as lens Gp in the present invention, and the seventh lens L7 is referred to as lens Lp in the present invention. The nth lens is the tenth lens L10. Lenses Gp and Lp are made of resin, while the others are made of glass.

[0343] (2) Numerical Example

[0344] Next, as numerical examples in which specific numerical values ​​are applied to the imaging lens, "lens data," "various specification values," "aspheric coefficients," and "focal lengths of each lens" are shown. Figure 16 The longitudinal aberration diagram of the imaging lens when focusing at infinity is shown in FIG.

[0345] (Lens data)

[0346]

[0347]

[0348] (various specifications)

[0349] F 5.000 Fno 1.640 θ 63.000

[0350] (Aspheric coefficient)

[0351] Face number k A4 A6 A8 A10 1 -6.0439 -4.69873E-04 -5.24473E-07 4.64210E-06 -3.24567E-07 2 -0.0551 2.41911E-04 1.28585E-04 -2.77407E-05 6.91451E-06 8 0.0000 -4.87395E-05 -2.88226E-05 9.53005E-06 -1.00318E-06 9 0.0000 -2.80812E-04 2.86822E-05 1.86585E-06 -1.90598E-07 14 0.0000 -9.42254E-04 -8.24074E-06 -4.78607E-06 6.67993E-07 15 0.0000 3.82515E-03 -7.89553E-04 7.88805E-05 -4.67713E-06 16 0.0000 -3.39389E-04 -1.94959E-04 3.81290E-05 -3.12302E-06 17 0.0000 -6.01218E-03 6.63009E-04 -5.37122E-05 2.95568E-06

[0352] Face number A12 A14 1 9.36771E-09 -1.01629E-10 2 -6.18819E-07 2.17766E-08 8 5.28288E-08 -1.08234E-09 9 1.03609E-08 -1.99251E-10 14 -3.48786E-08 6.64742E-10 15 1.41934E-07 -1.66528E-09 16 1.13727E-07 -1.56079E-09 17 -9.57011E-08 1.33647E-09

[0353] (Focal length of each lens)

[0354]

[0355]

[0356] [Table 1]

[0357] Example 1 Example 2 Example 3 Reference Example (1) f / f2p -0.212 -0.105 -0.111 -0.102 (2) ctGA / f 0.657 0.794 0.778 0.846 (3) fs / f 2.136 2.707 2.653 2.078 (4) f×tan(θ) / Yh 2.368 2.421 2.695 2.272 (5) Ng1 1.851 1.859 1.856 1.851 (6) Ng2 1.744 1.764 1.776 1.620 (7) Dpp / f 0.040 0.030 0.059 0.106 (8) Pair×f 0.065 0.076 -0.077 -0.111 (9) f1G / f -2.163 -2.686 -4.196 -6.478 (10) DD / LL 0.679 0.668 0.579 0.663 (11) L / Yh 7.841 7.341 7.930 8.020 (12) fL / f 2.319 2.694 2.490 -1.175 Example 5 Example 6 Example 7 Example 8 (1) f / f2p -0.102 -0.146 -0.106 -0.098 (2) ctGA / f 0.846 0.686 0.607 0.677 (3) fs / f 2.078 2.737 2.216 3.454 (4) f×tan(θ) / Yh 2.272 2.367 2.367 2.367 (5) Ng1 1.859 1.859 1.851 1.859 (6) Ng2 1.750 1.627 1.623 1.627 (7) Dpp / f 0.106 0.053 0.064 0.070 (8) Pair×f 0.066 -0.035 -0.018 -0.033 (9) f1G / f -6.478 -2.384 -4.230 -7.396 (10) DD / LL 0.802 0.564 0.558 0.569 (11) L / Yh 8.020 7.839 7.839 7.839 (12) fL / f -1.175 2.273 2.249 -4.059

[0358] [Table 2]

[0359]

[0360]

[0361] For the imaging lenses of Examples 1 to 3, the following results were obtained when the field of view (FOV) fluctuations at room temperature, at an ambient temperature of 125°C, and at an ambient temperature of -20°C (at 80-degree incidence) were determined. The FOV fluctuation at 125°C was less than ±0.200°, and the FOV fluctuation at -20°C was less than ±0.100°. The same range of FOV fluctuations at various temperatures was also observed for the imaging lenses of the Reference Example and Examples 5 to 10. Therefore, it was confirmed that imaging lenses with minimal FOV fluctuations were obtained even under large changes in ambient temperature. In particular, the imaging lenses of each example exhibited minimal FOV fluctuations even in an extremely high temperature environment of 125°C, enabling excellent imaging performance even in harsh environments.

[0362] [Example 1]: Viewing angle at room temperature: 126 degrees

[0363] Field of view change at 125°C: +0.185°

[0364] Field of view change at -20°C: -0.094°

[0365] [Example 2]: Viewing angle at room temperature: 132 degrees

[0366] Field of view change at 125°C: -0.013°

[0367] Field of view change at -20°C: -0.020°

[0368] [Example 3]: Viewing angle at room temperature: 132 degrees

[0369] Field of view change at 125°C: -0.067°

[0370] Field of view change at -20°C: -0.020°

[0371] Industrial Applicability

[0372] The imaging lens according to the present invention includes a resin lens, thereby achieving weight reduction and cost reduction, and can suppress fluctuations in the angle of view associated with changes in ambient temperature.

Claims

1. An imaging lens, characterized in that: The imaging lens is composed of n lenses, the n lenses including a first lens with a concave surface on the image side and a second lens with a concave surface on the object side, which are arranged in order from the object side, and an nth lens with positive optical power arranged closest to the image side, 6≤n≤10, When an aperture is arranged between the first lens and the nth lens, the object side of the aperture is defined as the first lens group, and the image side of the aperture is defined as the second lens group, The lens disposed most toward the image side in the first group has positive refractive power, the first lens has negative refractive power, and the first group as a whole has negative refractive power. The second group includes a lens Gp having a refractive index N corresponding to the d-line of N<1.68 and an Abbe number V corresponding to the d-line of 16<V<31. The lens arranged adjacent to the lens Gp is ​​a resin lens Lp. The imaging lens meets the following conditions: -0.59<f / fp<-0.01·····(1) -9.0<f1G / f<-2.00·····(9) in, f: focal length of the imaging lens fp: the combined focal length of the lens Gp and the lens Lp f1G: Focal length of the first group.

2. An imaging lens, characterized in that: The imaging lens is composed of n lenses, the n lenses including a first lens with a concave surface on the image side and a second lens with a concave surface on the object side, which are arranged in order from the object side, and an nth lens with positive optical power arranged closest to the image side, 6≤n≤10, When an aperture is arranged between the first lens and the nth lens, the object side of the aperture is defined as the first lens group, and the image side of the aperture is defined as the second lens group, The first group is composed of three or less lenses including the first lens and the second lens, the first lens having negative refractive power, and the first group as a whole having negative refractive power, and the second group includes a lens Gp having a refractive index N corresponding to the d-line of N<1.68 and an Abbe number V corresponding to the d-line of 16<V<31. The lens arranged adjacent to the lens Gp is ​​a resin lens Lp. For the mutually adjacent lenses Gp and Lp, at least one glass lens having substantial optical power is disposed on the object side and image side thereof, respectively. The imaging lens meets the following conditions: -0.59<f / fp<-0.01·····(1) in, f: focal length of the imaging lens fp: the combined focal length of the lens Gp and the lens Lp.

3. An imaging lens, characterized in that: The imaging lens is composed of n lenses, the n lenses including a first lens with a concave surface on the image side and a second lens with a concave surface on the object side, which are arranged in order from the object side, and an nth lens with positive optical power arranged closest to the image side, 6≤n≤10, When an aperture is arranged between the first lens and the nth lens, the object side of the aperture is defined as the first lens group, and the image side of the aperture is defined as the second lens group, The first lens has negative refractive power, the first group as a whole has negative refractive power, and the second group includes a lens Gp having a refractive index N corresponding to the d-line of N<1.68 and an Abbe number V corresponding to the d-line of 16<V<31. The lens arranged adjacent to the lens Gp is ​​a resin lens Lp. The imaging lens meets the following conditions: -0.59<f / fp<-0.01·····(1) 2.078<fs / f<4.5·····(3) 1.60<Ng2<1.89·····(6) in, f: focal length of the imaging lens fp: the combined focal length of the lens Gp and the lens Lp fs: Focal length of the lens adjacent to the image side of the aperture Ng2: the refractive index of the second lens corresponding to the d-line.

4. The imaging lens according to any one of claims 1 to 3, The following conditions are met: 0.1<ctGA / f<1.2·····(2) in, ctGA: the sum of the center thickness of the lens Gp and the center thickness of the lens Lp.

5. The imaging lens according to any one of claims 1 to 3, A lens having a convex image side is disposed adjacent to the object side of the diaphragm, and a lens having positive refractive power is disposed adjacent to the image side of the diaphragm.

6. The imaging lens according to any one of claims 1 to 3, The following conditions are met: 1.8<f×tan(θ) / Yh<3.2·····(4) in, Yh: Maximum image height of the imaging lens θ: half field of view angle of the imaging lens.

7. The imaging lens according to any one of claims 1 to 3, The following conditions are met: 1.8<Ng1<2.0·····(5) in, Ng1: the refractive index of the first lens corresponding to the d-line.

8. The imaging lens according to any one of claims 1 to 3, The following conditions are met: 0.01<Dpp / f<0.40·····(7) in, Dpp: The distance between the lens Gp and the lens Lp on the optical axis.

9. The imaging lens according to any one of claims 1 to 3, The following conditions are met: -0.3<Pair×f<0.3·····(8) in, Pair: The sum of the focal lengths of the object side and image side of the air lens formed between the lens Gp and the lens Lp, expressed as (1-n1) / r1-(1-n2) / r2 Here, n1: The refractive index of the lens arranged on the object side among the lens Gp and the lens Lp corresponding to the d-line n2: the refractive index of the lens arranged on the image side among the lens Gp and the lens Lp corresponding to the d-line r1: The radius of curvature of the object side of the air lens r2: the radius of curvature of the image side of the air lens.

10. The imaging lens according to any one of claims 1 to 3, The lens Gp is ​​a biconcave lens, and the lens Lp is a biconvex lens.

11. The imaging lens according to any one of claims 1 to 3, The following conditions are met: 0.40<DD / LL<0.95·····(10) DD: The sum of the center thicknesses of the first lens to the nth lens LL: The distance on the optical axis from the object-side surface of the first lens to the image-side surface of the n-th lens.

12. A camera device, characterized in that: have: The imaging lens according to any one of claims 1 to 11; and The imaging element converts the optical image formed by the imaging lens on the image side of the imaging lens into an electrical signal.

Images