Camera optical system and camera device

Abstract

This invention proposes a camera optical system and camera device. The camera optical system comprises, from the object side to the image side, a front group, an aperture, and a rear group. The front group, from the object side to the image side, comprises, in sequence, a first group with negative optical power and a second group with positive optical power. The second group comprises, a third lens, and a fourth lens located adjacent to the third lens on the image side and positioned closest to the image side. When the Abbe number of the third lens is set to ν21, the Abbe number of the fourth lens is set to ν22, the focal length of the third lens is set to f3, and the focal length of the fourth lens is set to f4, the following conditional expression is satisfied:

Description

Technical Field

[0001] This invention relates to a camera optical system and a camera device. Background Technology

[0002] A camera optical system for vehicle-mounted cameras or surveillance cameras is described in Patent Document 1. The camera optical system of Patent Document 1 comprises an aperture stop, a first lens group disposed on the object side of the aperture stop, and a second lens group disposed on the image side of the aperture stop. The first lens group, from the object side, includes, in sequence, a first lens, a second lens, a third lens, and a fourth lens. The second lens group, from the object side, includes, in sequence, a fifth lens, a sixth lens, and a seventh lens. The sixth and seventh lenses constitute a conjoined lens. The conjoined lens is disposed on the image side closest to the image and corrects chromatic aberration.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-107425 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In camera optics systems used in vehicle cameras or surveillance cameras, good correction of chromatic aberration is further required to obtain clear images.

[0008] In view of the above problems, the objective of the present invention is to provide a camera optical system capable of effectively correcting chromatic aberration, and a camera device equipped with the camera optical system.

[0009] Technical solutions adopted to solve technical problems

[0010] To address the aforementioned issues, in one embodiment of the imaging optical system of the present invention, a front group, an aperture, and a rear group are provided sequentially from the object side toward the image side.

[0011] The front group, arranged sequentially from the object side toward the image side, includes: a first group with negative optical power and a second group with positive optical power.

[0012] The second group includes: a second group of first lenses, and a second group of second lenses adjacent to the second group of first lenses on the image side and disposed on the image side closest to the image side.

[0013] When the Abbe number of the first lens in the second group is set to ν21, the Abbe number of the second lens in the second group is set to ν22, the focal length of the first lens in the second group is set to f3, and the focal length of the second lens in the second group is set to f4, the following condition is satisfied:

[0014] ν21 < 30.000

[0015] 44.000 < ν22

[0016] 0.000 < |f3 / f4| < 0.500.

[0017] In one embodiment of the camera device of the present invention, it includes: a camera optical system; and a camera element disposed on the image side of the camera optical system. Attached Figure Description

[0018] Figure 1 This is an explanatory diagram of the camera device according to Embodiment 1.

[0019] Figure 2 This is a diagram showing the data of the camera optical system in Embodiment 1.

[0020] Figure 3 It means Figure 1 The diagram shows the spherical aberration of the camera optical system.

[0021] Figure 4 It means Figure 1 The diagram shows the magnification chromatic aberration of the camera optical system.

[0022] Figure 5 It means Figure 1 The diagram shows the astigmatism and distortion of the camera optical system.

[0023] Figure 6 It means Figure 1 The diagram shows the lateral aberrations of the camera optical system.

[0024] Figure 7 This is an explanatory diagram of the camera device according to Embodiment 2.

[0025] Figure 8 This is a diagram showing the data of the camera optical system in Embodiment 2.

[0026] Figure 9 It means Figure 7 The diagram shows the spherical aberration of the camera optical system.

[0027] Figure 10 It means Figure 7 The diagram shows the magnification chromatic aberration of the camera optical system.

[0028] Figure 11 It means Figure 7 The diagram shows the astigmatism and distortion of the camera optical system.

[0029] Figure 12 It means Figure 7The diagram shows the lateral aberrations of the camera optical system.

[0030] Figure 13 This is an explanatory diagram of the camera device according to Embodiment 3.

[0031] Figure 14 This is a diagram showing the data of the camera optical system in Embodiment 3.

[0032] Figure 15 It means Figure 13 The diagram shows the spherical aberration of the camera optical system.

[0033] Figure 16 It means Figure 13 The diagram shows the magnification chromatic aberration of the camera optical system.

[0034] Figure 17 It means Figure 13 The diagram shows the astigmatism and distortion of the camera optical system.

[0035] Figure 18 It means Figure 13 The diagram shows the lateral aberrations of the camera optical system.

[0036] Figure 19 This is an explanatory diagram of the camera device in Embodiment 4.

[0037] Figure 20 This is a diagram showing the data of the camera optical system in Embodiment 4.

[0038] Figure 21 It means Figure 19 The diagram shows the spherical aberration of the camera optical system.

[0039] Figure 22 It means Figure 19 The diagram shows the magnification chromatic aberration of the camera optical system.

[0040] Figure 23 It means Figure 19 The diagram shows the astigmatism and distortion of the camera optical system.

[0041] Figure 24 It means Figure 19 The diagram shows the lateral aberrations of the camera optical system.

[0042] Figure 25 This is an explanatory diagram of the camera device in Embodiment 5.

[0043] Figure 26 This is a diagram showing the data of the camera optical system in Embodiment 5.

[0044] Figure 27 It means Figure 25The diagram shows the spherical aberration of the camera optical system.

[0045] Figure 28 It means Figure 25 The diagram shows the magnification chromatic aberration of the camera optical system.

[0046] Figure 29 It means Figure 25 The diagram shows the astigmatism and distortion of the camera optical system.

[0047] Figure 30 It means Figure 25 The diagram shows the lateral aberrations of the camera optical system.

[0048] Figure 31 This is an explanatory diagram of the camera device according to Embodiment 6.

[0049] Figure 32 This is a diagram showing the data of the camera optical system in Embodiment 6.

[0050] Figure 33 It means Figure 31 The diagram shows the spherical aberration of the camera optical system.

[0051] Figure 34 It means Figure 31 The diagram shows the magnification chromatic aberration of the camera optical system.

[0052] Figure 35 It means Figure 31 The diagram shows the astigmatism and distortion of the camera optical system.

[0053] Figure 36 It means Figure 31 The diagram shows the lateral aberrations of the camera optical system.

[0054] Figure 37 This is an explanatory diagram of the camera device according to Embodiment 7.

[0055] Figure 38 This is a diagram showing the data of the camera optical system in Embodiment 7.

[0056] Figure 39 It means Figure 37 The diagram shows the spherical aberration of the camera optical system.

[0057] Figure 40 It means Figure 37 The diagram shows the magnification chromatic aberration of the camera optical system.

[0058] Figure 41 It means Figure 37 The diagram shows the astigmatism and distortion of the camera optical system.

[0059] Figure 42 It means Figure 37 The diagram shows the lateral aberrations of the camera optical system.

[0060] Explanation of icon numbers

[0061] 10…First lens, 20…Second lens, 30…Third lens, 40…Fourth lens, 50…Fifth lens, 60…Sixth lens, 70…Seventh lens, 75…Joint lens, 80…Infrared cutoff filter, 90…Mask, 100…Camera optical system, 110…Front group, 111…First group, 112…Second group, 120…Rear group, 140…Camera element, 200…Camera device, L…Optical axis, La…Object side, Lb…Image side. Detailed Implementation

[0062] Hereinafter, embodiments of a camera device 200 equipped with the camera optical system 100 of the present invention will be described. The camera device 200 is used for vehicle-mounted cameras or surveillance cameras. In particular, the camera optical system 100 is suitable for surveillance cameras used for in-vehicle monitoring.

[0063] (Implementation Method 1)

[0064] Figure 1 This is an explanatory diagram of the camera device 200 according to Embodiment 1. (As shown...) Figure 1 As shown, the imaging device 200 of this embodiment includes an imaging optical system 100 and an imaging element 140. The imaging optical system 100, from the object side La towards the image side Lb, includes a front group 110, an aperture 130, a rear group 120, and an infrared cutoff filter 80. On the image side Lb of the infrared cutoff filter 80, a light-transmitting cover 90 and the imaging element 140 are arranged sequentially from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0065] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0066] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. Regarding the third lens 30, its lens surface 31 on the object side La has a convex shape near the optical axis L and a concave shape at its periphery, while its lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The fourth lens 40 has a concave shape on its lens surface 41 on the object side La and a convex shape on its lens surface 42 on the image side Lb. The fourth lens 40 has aspherical shapes on both surfaces.

[0067] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0068] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0069] Figure 2 This is a diagram showing data of the camera optical system 100 according to Embodiment 1. Furthermore, Figure 2 The values ​​shown have been rounded to the nearest integer.

[0070] exist Figure 2 The following data are shown. Here, in these data, the overall length of the lens system is the distance along the optical axis L from the lens surface 11 on the object side La of the first lens 10 to the image surface of the imaging element 140. The overall length between the first lens and the seventh lens is the distance along the optical axis L from the lens surface 11 on the object side La of the first lens 10 to the lens surface 72 on the image side Lb of the seventh lens.

[0071] The overall focal length of the lens system (Effective Focal Length: f0)

[0072] Total length of the lens system (Total Track: d0)

[0073] The overall F-number (Fno) of the lens system

[0074] Maximum half field of view (ω)

[0075] Pupil Diameter

[0076] The total length between the first and seventh lenses (L1R1-L7R2 Track)

[0077] In addition, Figure 2 The following shows the lens data for each lens. In the lens data, the surface number contains... The surface is aspherical. R is the radius of curvature. d is the interplanar spacing. N is the refractive index. ν is the Abbe number. f is the focal length. sd is the effective radius. Sag is the subtraction. The units for radius of curvature, interplanar spacing, focal length, effective radius, and subtraction are mm (millimeters). Additionally, in... Figure 2 The aspherical coefficients representing the shape of the aspherical surface are shown in the face numbering.

[0078] Regarding the camera optical system 100, when the Abbe number of the third lens 30 (the first lens of the second group) is set to ν21, the Abbe number of the fourth lens 40 (the second lens of the second group) is set to ν22, the focal length of the third lens 30 (the first lens of the second group) is set to f3, and the focal length of the fourth lens 40 (the second lens of the second group) is set to f4, the following conditional expression is satisfied:

[0079] ν21 < 30.000 (1)

[0080] 44.000 < ν22(2)

[0081] 0.000 < |f3 / f4| < 0.500(3).

[0082] More preferably, condition (1) satisfies the following condition:

[0083] 21.000 < ν21 < 30.000 (1A).

[0084] More preferably, condition (2) satisfies the following condition:

[0085] 50.000 < ν22 (2A).

[0086] In this embodiment,

[0087] ν21=21.621

[0088] ν22=56.131

[0089] f3 = 4.689

[0090] f4 = -76.624.

[0091] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.061, satisfying condition (3).

[0092] Regarding the imaging optical system 100, when the Abbe number of the third lens 30 (the first lens of the second group) is set to ν21, the Abbe number of the fourth lens 40 (the second lens of the second group) is set to ν22, the depression of the object-side lens surface 71 of the seventh lens 70 (the image-side lens) is set to Sag71, and the effective radius of the object-side lens surface 71 of the seventh lens 70 (the image-side lens) is set to sd71, the following conditional expression is satisfied:

[0093] ν21 < 30.000 (1)

[0094] 44.000 < ν22(2)

[0095] 0.200 < |Sag71 / sd71| < 0.750 (4).

[0096] More preferably, condition (1) satisfies the following condition:

[0097] 21.000 < ν21 < 30.000 (1A).

[0098] More preferably, condition (2) satisfies the following condition:

[0099] 50.000 < ν22 (2A).

[0100] More preferably, condition (4) satisfies the following condition:

[0101] 0.300 < |Sag71 / sd71| < 0.600 (4A).

[0102] In this embodiment,

[0103] ν21=21.621

[0104] ν22=56.131

[0105] Sag71 = 1.081

[0106] sd71 = 1.968.

[0107] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.550, satisfying condition (4) (4A).

[0108] Regarding the imaging optical system 100, when the depression of the object-side lens surface 31 of the third lens 30 (the first lens of the second group) is set to Sag31, and the effective radius of the object-side lens surface 31 of the third lens 30 (the first lens of the second group) is set to sd31, the following conditional expression is satisfied:

[0109] 0.000 < |Sag31 / sd31| < 0.250(5).

[0110] In this embodiment,

[0111] Sag31 = -0.010

[0112] sd31 = 1.781.

[0113] Therefore, |Sag31 / sd31|=0.005, which satisfies condition (5).

[0114] Regarding the camera optical system 100, when the focal length of the entire lens system is set to f0 and the focal length of the second group 112 is set to f34, the following condition is satisfied:

[0115] 2.000 < f34 / f0 < 6.000 (6).

[0116] In this embodiment,

[0117] f0 = 1.334

[0118] f34 = 5.828.

[0119] Therefore, f34 / f0 = 4.369, which satisfies condition (6).

[0120] Regarding the imaging optical system 100, when the focal length of the entire lens system is set to f0, the radius of curvature of the object-side lens surface 61 of the sixth lens 60 (object-side lens) is set to R61, and the radius of curvature of the object-side lens surface 71 of the seventh lens 70 (image-side lens) is set to R71, the following conditional expression is satisfied:

[0121] -10.000 < R61 / f0 < -2.000 (7)

[0122] 1.000 < R71 / f0 < 2.000(8).

[0123] In this embodiment,

[0124] f0 = 1.334

[0125] R61 = -6.507

[0126] R71 = 1.750.

[0127] Therefore, R61 / f0 = -4.878, satisfying condition (7). R71 / f0 = 1.312, satisfying condition (8).

[0128] Regarding the imaging optical system 100, when the radius of curvature of the object-side lens surface 61 of the sixth lens 60 (object-side lens) is set to R61, and the radius of curvature of the image-side lens surface 62 of the sixth lens 60 (object-side lens) is set to R62, the following conditional expression is satisfied:

[0129] 0.000 < (R61+R62) / (R61-R62) < 1.000 (9).

[0130] In this embodiment,

[0131] R61 = -6.507

[0132] R62 = 1.750.

[0133] Therefore, (R61+R62) / (R61-R62) = 0.576, which satisfies condition (9).

[0134] Regarding the camera optical system 100, when the focal length of the entire lens system is set to f0 and the total length of the entire lens system is set to d0, the following conditional expression is satisfied:

[0135] 10.000 < d0 / f0 < 15.000 (10).

[0136] In this embodiment,

[0137] f0 = 1.334

[0138] d0 = 16.770.

[0139] Therefore, d0 / f0 = 12.572, which satisfies condition (10).

[0140] Regarding the imaging optical system 100, when the radius of curvature of the object-side lens surface 51 of the fifth lens 50 is set to R51, and the radius of curvature of the image-side lens surface 52 of the fifth lens 50 is set to R52, the following conditional expression is satisfied:

[0141] |R52| < |R51|(11).

[0142] In this embodiment,

[0143] R51 = 4.990

[0144] R52 = -3.750.

[0145] Therefore, condition (11) is satisfied.

[0146] Regarding the camera optical system 100, when the Abbe number of the sixth lens 60 is set to ν6 and the Abbe number of the seventh lens 70 is set to ν7, the following conditional expression is satisfied:

[0147] ν6 < 30.000 (12)

[0148] 50.000 < ν7 (13).

[0149] In this embodiment,

[0150] ν6=21.621

[0151] ν7 = 56.131.

[0152] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.131, satisfying condition (13).

[0153] For the camera optical system 100, when the maximum field of view is set to ω, the following condition is satisfied:

[0154] 90 < ω < 120…(14).

[0155] In this embodiment,

[0156] ω = 106.

[0157] Therefore, condition (14) is satisfied.

[0158] Regarding the camera optical system 100, when the thickness of the first lens 10 is set to T1 and the focal length of the entire lens system is set to f0, the following conditional expression is satisfied:

[0159] 0.700 < T1 / f0 < 0.900 (15).

[0160] In this embodiment,

[0161] T1 = 1.000

[0162] f0 = 1.334.

[0163] Therefore, T1 / f0 = 0.750, which satisfies condition (15).

[0164] Regarding the imaging optical system 100, when the focal length of the entire lens system is set to f0, and the radius of curvature of the lens surface 31 on the object side of the third lens 30 (the first lens of the second group) is set to R31, the following conditional expression is satisfied:

[0165] 8.000 < |R31 / f0|(16)

[0166] In this embodiment,

[0167] f0 = 1.334

[0168] R31 = 15.080.

[0169] Therefore, |R31 / f0|=11.305, which satisfies condition (16).

[0170] Regarding the camera optical system 100, when the focal length of the entire lens system is set to f0 and the focal length of the joint lens 75 is set to f67, the following condition is satisfied:

[0171] 2.000 < f67 / f0 < 7.000 (17).

[0172] In this embodiment,

[0173] f0 = 1.334

[0174] f67 = 6.701.

[0175] Therefore, f67 / f0 = 5.024, which satisfies condition (17).

[0176] (Effects)

[0177] The imaging optical system 100 of this embodiment satisfies conditions (1)(1A)(2)(2A)(3), and therefore, chromatic aberration can be well corrected in the third lens 30 and the fourth lens 40. When conditions (1)(1A)(2)(2A) are satisfied, if the value of condition (3) exceeds the upper limit, it is difficult to properly correct chromatic aberration because the lens focal length of the fourth lens 40 is too large. Here, if the value of condition (1A) is below the lower limit, chromatic aberration can be well corrected, but the cost of the glass material of the third lens 30 increases.

[0178] The imaging optical system 100 of this embodiment satisfies conditions (1)(1A)(2)(2A)(4), and therefore, chromatic aberration can be well corrected in the joint lens 75. When conditions (1)(1A)(2)(2A) are satisfied, if the value of condition (4) is below the lower limit, it is difficult to well correct chromatic aberration in the joint lens 75 because the joint surfaces of the joint lens 75, namely lens surface 62 and lens surface 71, are close to planar shapes. If the value of condition (4) exceeds the upper limit, chromatic aberration can be well corrected in the joint lens 75, but the amount of depression of lens surface 62 and lens surface 71 is too large relative to the effective radius. Therefore, the productivity of the sixth lens 60 and the seventh lens 70 is reduced, and the cost is increased. Especially when the lens surface 71 on the object side La of the seventh lens 70 is convex, if the depression is too large relative to the effective radius, the lens surface 71 protrudes significantly. Therefore, when molding the seventh lens, the time it takes for the resin flowing in from the gate located on the side of the flange of the seventh lens 70 to fill to the top of the lens surface 71 becomes longer. As a result, the productivity of the seventh lens 70 is easily and significantly reduced.

[0179] The imaging optical system 100 of this embodiment satisfies condition (5), therefore, it can effectively correct various aberrations and suppress the generation of ghosting in the lens surface 31 on the object side of the third lens 30. When the value of condition (5) is below the lower limit, it is difficult to effectively correct various aberrations because the lens surface 31 becomes flat. When the value of condition (5) exceeds the upper limit, ghosting is easily generated in the lens surface 31.

[0180] The camera optical system 100 of this embodiment satisfies condition (6), and therefore can effectively correct various aberrations.

[0181] The imaging optical system 100 of this embodiment satisfies conditions (7) and (8), and therefore, it can effectively correct various aberrations. When the value of condition (7) is below the lower limit, it is difficult to effectively correct various aberrations because the radius of curvature of the lens surface 61 on the object side of the sixth lens 60 is too small. When the value of condition (7) exceeds the upper limit, the productivity of the sixth lens 60 decreases and the cost increases because the radius of curvature of the lens surface 61 on the object side of the sixth lens 60 is too large. When the value of condition (8) is below the lower limit, the productivity of the seventh lens 70 decreases and the cost increases because the radius of curvature of the lens surface 71 on the object side of the seventh lens 70 is too large. When the value of condition (8) exceeds the upper limit, it is difficult to effectively correct various aberrations because the radius of curvature of the lens surface 71 on the object side of the seventh lens 70 is too small.

[0182] The camera optical system 100 of this embodiment satisfies condition (9), and therefore can effectively correct various aberrations.

[0183] The imaging optical system 100 of this embodiment satisfies condition (10), thus it can suppress the overall increase in the length of the lens system and can effectively correct various aberrations. When the value of condition (10) is lower than the lower limit, it is difficult to effectively correct various aberrations. When the value of condition (10) exceeds the upper limit, each lens system tends to increase in size, and the overall length of the lens system tends to increase.

[0184] The fifth lens 50 is made of glass. The imaging optical system 100 of this embodiment satisfies condition (11), so even if the fifth lens 50, which is adjacent to the aperture 130 on the image side Lb, is subjected to temperature changes, the reduction in the optical properties of the fifth lens 50 can be suppressed.

[0185] The imaging optical system 100 of this embodiment satisfies conditions (12) and (13), therefore, the combined lens 75 can effectively correct chromatic aberration.

[0186] The camera optical system 100 of this embodiment satisfies condition (14). Therefore, the camera device 200 using the camera optical system 100 can capture a wide range of images and can suppress the significant reduction in the amount of light in the periphery relative to the amount of light in the center.

[0187] The imaging optical system 100 of this embodiment satisfies condition (15), thus ensuring the strength of the first lens 10 and suppressing the overall length of the lens system from increasing. When the value of condition (15) is below the lower limit, the strength of the first lens 10 decreases because the thickness of the first lens 10 is too thin. When the value of condition (15) exceeds the upper limit, the strength of the first lens 10 can be ensured, but the overall length of the lens system tends to increase.

[0188] The imaging optical system 100 of this embodiment satisfies condition (16), thus suppressing the production cost of the third lens 30. When the value of condition (16) is below the lower limit, the productivity of the third lens 30 decreases and the cost increases because the radius of curvature of the lens surface 31 on the object side of the third lens 30 is too large.

[0189] The imaging optical system 100 of this embodiment satisfies condition (17), thus it can suppress the overall increase in the length of the lens system and can effectively correct various aberrations. When the value of condition (17) is below the lower limit, it is difficult to effectively correct chromatic aberration and distortion aberration in the joint lens 75. When the value of condition (17) exceeds the upper limit, the overall length of the lens system tends to increase.

[0190] The third lens 30 has positive optical power. The lens surface 31 on the object side La of the third lens 30 has a convex shape near the optical axis L and a concave shape at the periphery. The lens surface 32 on the image side Lb of the third lens 30 has a convex shape. As a result, astigmatism and distortion can be effectively corrected.

[0191] Figure 3 It means Figure 1 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 4 It means Figure 1 The diagram of magnification chromatic aberration of the camera optical system 100 shown illustrates the magnification chromatic aberration at the maximum half field of view. Figure 5 It means Figure 1 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 6 It means Figure 1 The diagram of the lateral aberrations of the imaging optical system 100 shown illustrates the lateral aberrations in the tangential direction (Y direction) and the radial direction (X direction).

[0192] In addition, Figures 3-6 In the diagram, aberrations at wavelengths of 486nm, 546nm, and 656nm are labeled B, G, and R. Regarding... Figure 5 The astigmatism shown is labeled S for the radial direction and T for the tangential direction.

[0193] like Figures 3-6 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), and lateral aberration are corrected to appropriate levels.

[0194] (Implementation Method 2)

[0195] Figure 7 This is an explanatory diagram of the camera device 200 according to Embodiment 2. (As shown...) Figure 7 As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0196] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0197] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. Regarding the third lens 30, its lens surface 31 on the object side La has a convex shape near the optical axis L and a concave shape around the periphery; its lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The fourth lens 40 has a concave shape on its lens surface 41 on the object side La and a convex shape on its lens surface 42 on the image side Lb. The fourth lens 40 has aspherical shapes on both surfaces.

[0198] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0199] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0200] (Lens structure)

[0201] Figure 8This is a diagram showing the data of the camera optical system 100 in Embodiment 2. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (17) described in Embodiment 1.

[0202] In this embodiment,

[0203] ν21=21.621

[0204] ν22=56.131

[0205] f3 = 4.847

[0206] f4 = -48.763.

[0207] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.099, satisfying condition (3).

[0208] In this embodiment,

[0209] ν21=21.621

[0210] ν22=56.131

[0211] Sag71 = 1.063

[0212] sd71 = 1.963.

[0213] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.542, satisfying condition (4) (4A).

[0214] In this embodiment,

[0215] Sag31 = -0.012

[0216] sd31 = 1.772.

[0217] Therefore, |Sag31 / sd31|=0.007, which satisfies condition (5).

[0218] In this embodiment,

[0219] f0 = 1.332

[0220] f34 = 6.268.

[0221] Therefore, f34 / f0 = 4.707, which satisfies condition (6).

[0222] In this embodiment,

[0223] f0 = 1.332

[0224] R61 = -6.281

[0225] R71 = 1.915.

[0226] Therefore, R61 / f0 = -4.717, satisfying condition (7). R71 / f0 = 1.438, satisfying condition (8).

[0227] In this embodiment,

[0228] R61 = -6.281

[0229] R62 = 1.915.

[0230] Therefore, (R61+R62) / (R61-R62) = 0.533, which satisfies condition (9).

[0231] In this embodiment,

[0232] f0 = 1.332

[0233] d0 = 16.725.

[0234] Therefore, d0 / f0 = 12.559, which satisfies condition (10).

[0235] In this embodiment,

[0236] R51 = 4.380

[0237] R52 = -3.640.

[0238] Therefore, condition (11) is satisfied.

[0239] In this embodiment,

[0240] ν6=21.621

[0241] ν7 = 56.131.

[0242] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.131, satisfying condition (13).

[0243] In this embodiment,

[0244] ω = 106.

[0245] Therefore, condition (14) is satisfied.

[0246] In this embodiment,

[0247] T1 = 1.000

[0248] f0 = 1.332.

[0249] Therefore, T1 / f0 = 0.751, which satisfies condition (15).

[0250] In this embodiment,

[0251] f0 = 1.332

[0252] R31 = 15.460.

[0253] Therefore, |R31 / f0|=11.610, which satisfies condition (16).

[0254] In this embodiment,

[0255] f0 = 1.332

[0256] f67 = 6.607.

[0257] Therefore, f67 / f0 = 4.961, which satisfies condition (17).

[0258] (Effects)

[0259] The camera optical system 100 of Embodiment 2 satisfies the same conditions (1) to (17) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0260] Figure 9 It means Figure 7 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 10 It means Figure 7 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 11 It means Figure 7 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 12 It means Figure 7 A diagram showing the lateral aberrations of the camera optical system 100.

[0261] like Figures 9-12 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0262] (Implementation Method 3)

[0263] Figure 13 This is an explanatory diagram of the camera device 200 according to Embodiment 3. Figure 13As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0264] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0265] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. Regarding the third lens 30, its lens surface 31 on the object side La has a convex shape near the optical axis L and a concave shape at its periphery, while its lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The fourth lens 40 has a concave shape on its lens surface 41 on the object side La and a convex shape on its lens surface 42 on the image side Lb. The fourth lens 40 has aspherical shapes on both surfaces.

[0266] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0267] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0268] (Lens structure)

[0269] Figure 14 This is a diagram showing the data of the camera optical system 100 in Embodiment 3. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (17) described in Embodiment 1.

[0270] In this embodiment,

[0271] ν21=21.621

[0272] ν22=56.131

[0273] f3 = 5.438

[0274] f4 = -52.794.

[0275] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.103, satisfying condition (3).

[0276] In this embodiment,

[0277] ν21=21.621

[0278] ν22=56.131

[0279] Sag71 = 1.065

[0280] sd71 = 1.989.

[0281] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.536, satisfying condition (4) (4A).

[0282] In this embodiment,

[0283] Sag31 = -0.081

[0284] sd31 = 1.736.

[0285] Therefore, |Sag31 / sd31|=0.047, which satisfies condition (5).

[0286] In this embodiment,

[0287] f0 = 1.333

[0288] f34 = 7.105.

[0289] Therefore, f34 / f0 = 5.332, which satisfies condition (6).

[0290] In this embodiment,

[0291] f0 = 1.333

[0292] R61 = -6.320

[0293] R71 = 1.963.

[0294] Therefore, R61 / f0 = -4.743, satisfying condition (7). R71 / f0 = 1.473, satisfying condition (8).

[0295] In this embodiment,

[0296] R61 = -6.320

[0297] R62 = 1.963.

[0298] Therefore, (R61+R62) / (R61-R62) = 0.526, which satisfies condition (9).

[0299] In this embodiment,

[0300] f0 = 1.333

[0301] d0 = 16.660.

[0302] Therefore, d0 / f0 = 12.502, which satisfies condition (10).

[0303] In this embodiment,

[0304] R51 = 4.313

[0305] R52 = -3.691.

[0306] Therefore, condition (11) is satisfied.

[0307] In this embodiment,

[0308] ν6=21.621

[0309] ν7 = 56.131.

[0310] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.131, satisfying condition (13).

[0311] In this embodiment,

[0312] ω = 106.

[0313] Therefore, condition (14) is satisfied.

[0314] In this embodiment,

[0315] T1 = 1.000

[0316] f0 = 1.333.

[0317] Therefore, T1 / f0 = 0.750, which satisfies condition (15).

[0318] In this embodiment,

[0319] f0 = 1.333

[0320] R31 = 72.116.

[0321] Therefore, |R31 / f0|=54.116, which satisfies condition (16).

[0322] In this embodiment,

[0323] f0 = 1.333

[0324] f67 = 6.430.

[0325] Therefore, f67 / f0 = 4.825, which satisfies condition (17).

[0326] (Effects)

[0327] The camera optical system 100 of Embodiment 3 satisfies the same conditions (1) to (17) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0328] Figure 15 It means Figure 13 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 16 It means Figure 13 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 17 It means Figure 13 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 18It means Figure 13 A diagram showing the lateral aberrations of the camera optical system 100.

[0329] like Figures 15-18 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0330] (Implementation Method 4)

[0331] Figure 19 This is an explanatory diagram of the camera device 200 according to Embodiment 4. Figure 19 As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0332] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0333] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. Regarding the third lens 30, its lens surface 31 on the object side La has a convex shape near the optical axis L and a concave shape at its periphery, while its lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The fourth lens 40 has a concave shape on its lens surface 41 on the object side La and a convex shape on its lens surface 42 on the image side Lb. The fourth lens 40 has aspherical shapes on both surfaces.

[0334] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0335] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0336] (Lens structure)

[0337] Figure 20 This is a diagram showing the data of the camera optical system 100 in Embodiment 4. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (17) described in Embodiment 1.

[0338] In this embodiment,

[0339] ν21=21.621

[0340] ν22=56.131

[0341] f3 = 5.632

[0342] f4 = -71.657.

[0343] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.079, satisfying condition (3).

[0344] In this embodiment,

[0345] ν21=21.621

[0346] ν22=56.131

[0347] Sag71 = 1.090

[0348] sd71 = 2.023.

[0349] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.539, satisfying condition (4) (4A).

[0350] In this embodiment,

[0351] Sag31 = 0.011

[0352] sd31 = 1.729.

[0353] Therefore, |Sag31 / sd31|=0.006, which satisfies condition (5).

[0354] In this embodiment,

[0355] f0 = 1.314

[0356] f34 = 7.237.

[0357] Therefore, f34 / f0 = 5.507, which satisfies condition (6).

[0358] In this embodiment,

[0359] f0 = 1.314

[0360] R61 = -7.335

[0361] R71 = 1.851.

[0362] Therefore, R61 / f0 = -5.582, satisfying condition (7). R71 / f0 = 1.408, satisfying condition (8).

[0363] In this embodiment,

[0364] R61 = -7.335

[0365] R62 = 1.851.

[0366] Therefore, (R61+R62) / (R61-R62) = 0.597, which satisfies condition (9).

[0367] In this embodiment,

[0368] f0 = 1.314

[0369] d0 = 16.786.

[0370] Therefore, d0 / f0 = 12.773, which satisfies condition (10).

[0371] In this embodiment,

[0372] R51 = 4.505

[0373] R52 = -3.634.

[0374] Therefore, condition (11) is satisfied.

[0375] In this embodiment,

[0376] ν6=21.621

[0377] ν7 = 56.131.

[0378] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.131, satisfying condition (13).

[0379] In this embodiment,

[0380] ω = 106.

[0381] Therefore, condition (14) is satisfied.

[0382] In this embodiment,

[0383] T1 = 1.000

[0384] f0 = 1.314.

[0385] Therefore, T1 / f0 = 0.761, which satisfies condition (15).

[0386] In this embodiment,

[0387] f0 = 1.314

[0388] R31 = 15.447.

[0389] Therefore, |R31 / f0|=11.755, which satisfies condition (16).

[0390] In this embodiment,

[0391] f0 = 1.314

[0392] f67 = 5.267.

[0393] Therefore, f67 / f0 = 4.008, which satisfies condition (17).

[0394] (Effects)

[0395] The camera optical system 100 of Embodiment 4 satisfies the same conditions (1) to (17) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0396] Figure 21 It means Figure 19 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 22 It means Figure 19 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 23 It means Figure 19 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 24 It means Figure 19 A diagram showing the lateral aberrations of the camera optical system 100.

[0397] like Figures 21-24 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0398] (Implementation Method 5)

[0399] Figure 25 This is an explanatory diagram of the camera device 200 according to Embodiment 5. Figure 25 As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0400] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0401] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. The lens surface 31 of the third lens 30 on the object side La has a concave shape, and the lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The lens surface 41 of the fourth lens 40 on the object side La has a concave shape, and the lens surface 42 on the image side Lb has a convex shape. The fourth lens 40 has aspherical shapes on both surfaces.

[0402] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0403] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0404] (Lens structure)

[0405] Figure 26This is a diagram showing the data of the camera optical system 100 in Embodiment 5. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (16) described in Embodiment 1.

[0406] In this embodiment,

[0407] ν21=21.621

[0408] ν22=56.131

[0409] f3 = 5.509

[0410] f4 = 61.760.

[0411] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.089, satisfying condition (3).

[0412] In this embodiment,

[0413] ν21=21.621

[0414] ν22=56.131

[0415] Sag71 = 1.020

[0416] sd71 = 1.992.

[0417] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.512, satisfying condition (4) (4A).

[0418] In this embodiment,

[0419] Sag31 = -0.186

[0420] sd31 = 1.796.

[0421] Therefore, |Sag31 / sd31|=0.104, which satisfies condition (5).

[0422] In this embodiment,

[0423] f0 = 1.417

[0424] f34 = 6.261.

[0425] Therefore, f34 / f0 = 4.419, which satisfies condition (6).

[0426] In this embodiment,

[0427] f0 = 1.417

[0428] R61 = -6.743

[0429] R71 = 2.023.

[0430] Therefore, R61 / f0 = -4.759, satisfying condition (7). R71 / f0 = 1.428, satisfying condition (8).

[0431] In this embodiment,

[0432] R61 = -6.743

[0433] R62 = 2.023.

[0434] Therefore, (R61+R62) / (R61-R62) = 0.538, which satisfies condition (9).

[0435] In this embodiment,

[0436] f0 = 1.417

[0437] d0 = 16.939.

[0438] Therefore, d0 / f0 = 11.957, which satisfies condition (10).

[0439] In this embodiment,

[0440] R51 = 4.343

[0441] R52 = -3.884.

[0442] Therefore, condition (11) is satisfied.

[0443] In this embodiment,

[0444] ν6=21.621

[0445] ν7 = 56.219.

[0446] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.219, satisfying condition (13).

[0447] In this embodiment,

[0448] ω = 108.

[0449] Therefore, condition (14) is satisfied.

[0450] In this embodiment,

[0451] T1 = 1.000

[0452] f0 = 1.417.

[0453] Therefore, T1 / f0 = 0.706, which satisfies condition (15).

[0454] In this embodiment,

[0455] f0 = 1.417

[0456] R31 = -46.001.

[0457] Therefore, |R31 / f0|=32.470, which satisfies condition (16).

[0458] (Effects)

[0459] The camera optical system 100 of Embodiment 5 satisfies the same conditions (1) to (16) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0460] Figure 27 It means Figure 25 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 28 It means Figure 25 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 29 It means Figure 25 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 30 It means Figure 25 A diagram showing the lateral aberrations of the camera optical system 100.

[0461] like Figures 27-30 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0462] (Implementation Method 6)

[0463] Figure 31 This is an explanatory diagram of the camera device 200 according to Embodiment 6. Figure 31As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0464] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0465] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. The lens surface 31 of the third lens 30 on the object side La has a concave shape, and the lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The lens surface 41 of the fourth lens 40 on the object side La has a concave shape, and the lens surface 42 on the image side Lb has a convex shape. The fourth lens 40 has aspherical shapes on both surfaces.

[0466] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0467] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0468] (Lens structure)

[0469] Figure 32 This is a diagram showing the data of the camera optical system 100 in Embodiment 6. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (16) described in Embodiment 1.

[0470] In this embodiment,

[0471] ν21=21.621

[0472] ν22=56.131

[0473] f3 = 5.502

[0474] f4 = 63.653.

[0475] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |f3 / f4| = 0.086, satisfying condition (3).

[0476] In this embodiment,

[0477] ν21=21.621

[0478] ν22=56.131

[0479] Sag71 = 1.002

[0480] sd71 = 1.979.

[0481] Therefore, ν21 = 21.621, satisfying condition (1) (1A). ν22 = 56.131, satisfying condition (2) (2A). |Sag71 / sd71| = 0.506, satisfying condition (4) (4A).

[0482] In this embodiment,

[0483] Sag31 = -0.181

[0484] sd31 = 1.790.

[0485] Therefore, |Sag31 / sd31|=0.101, which satisfies condition (5).

[0486] In this embodiment,

[0487] f0 = 1.412

[0488] f34 = 6.258.

[0489] Therefore, f34 / f0 = 4.432, which satisfies condition (6).

[0490] In this embodiment,

[0491] f0 = 1.412

[0492] R61 = -6.753

[0493] R71 = 2.030.

[0494] Therefore, R61 / f0 = -4.782, satisfying condition (7). R71 / f0 = 1.437, satisfying condition (8).

[0495] In this embodiment,

[0496] R61 = -6.753

[0497] R62 = 2.030.

[0498] Therefore, (R61+R62) / (R61-R62) = 0.538, which satisfies condition (9).

[0499] In this embodiment,

[0500] f0 = 1.412

[0501] d0 = 16.903.

[0502] Therefore, d0 / f0 = 11.970, which satisfies condition (10).

[0503] In this embodiment,

[0504] R51 = 4.342

[0505] R52 = -3.882.

[0506] Therefore, condition (11) is satisfied.

[0507] In this embodiment,

[0508] ν6=21.621

[0509] ν7 = 56.219.

[0510] Therefore, ν6 = 21.621, satisfying condition (12). ν7 = 56.219, satisfying condition (13).

[0511] In this embodiment,

[0512] ω = 108.

[0513] Therefore, condition (14) is satisfied.

[0514] In this embodiment,

[0515] T1 = 1.000

[0516] f0 = 1.412.

[0517] Therefore, T1 / f0 = 0.708, which satisfies condition (15).

[0518] In this embodiment,

[0519] f0 = 1.412

[0520] R31 = -47.186.

[0521] Therefore, |R31 / f0|=33.415, which satisfies condition (16).

[0522] (Effects)

[0523] The camera optical system 100 of Embodiment 6 satisfies the same conditions (1) to (16) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0524] Figure 33 It means Figure 31 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 34 It means Figure 31 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 35 It means Figure 31 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 36 It means Figure 31 A diagram showing the lateral aberrations of the camera optical system 100.

[0525] like Figures 33-36 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0526] (Implementation Method 7)

[0527] Figure 37 This is an explanatory diagram of the camera device 200 according to Embodiment 7. (As shown...) Figure 37 As shown, the imaging device 200 of this embodiment, like that of Embodiment 1, includes an imaging optical system 100 and an imaging element 140. The front group 110 is composed of a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 sequentially from the object side La towards the image side Lb. The rear group 120 is composed of a fifth lens 50, a sixth lens 60, and a seventh lens 70 sequentially from the object side La towards the image side Lb. The sixth lens 60 and the seventh lens 70 are joined lenses 75 using an adhesive. On the image side Lb of the seventh lens 70, a flat infrared cutoff filter 80, a light-transmitting cover 90, and the imaging element 140 are sequentially arranged from the object side La towards the image side Lb. The imaging element 140 is disposed on the imaging surface of the imaging optical system 100 on the image side Lb.

[0528] The front group 110, from the object side La towards the image side Lb, comprises: a first group 111 with negative optical power and a second group 112 with positive optical power. The first group 111, from the object side La towards the image side Lb, consists of a first lens 10 and a second lens 20. The first lens 10 is made of glass. The first lens 10 has negative optical power. The lens surface 11 of the first lens 10 on the object side La has a convex shape, and the lens surface 12 on the image side Lb has a concave shape. The second lens 20 is made of resin. The second lens 20 has negative optical power. The lens surface 21 of the second lens 20 on the object side La has a convex shape, and the lens surface 22 on the image side Lb has a concave shape. The second lens 20 has aspherical shapes on both surfaces.

[0529] The second group 112, from the object side La towards the image side Lb, consists of a third lens 30 (the first lens of the second group) and a fourth lens 40 (the second lens of the second group). The third lens 30 is made of resin. The third lens 30 has positive optical power. The lens surface 31 of the third lens 30 on the object side La has a concave shape, and the lens surface 32 on the image side Lb has a convex shape. The third lens 30 has aspherical shapes on both surfaces. The fourth lens 40 is made of resin. The fourth lens 40 has negative optical power. The lens surface 41 of the fourth lens 40 on the object side La has a concave shape, and the lens surface 42 on the image side Lb has a convex shape. The fourth lens 40 has aspherical shapes on both surfaces.

[0530] The rear group 120, from the object side La towards the image side Lb, consists of a fifth lens 50 and a joining lens 75. The joining lens 75, from the object side La towards the image side Lb, consists of a sixth lens 60 (object side lens) and a seventh lens 70 (image side lens). The sixth lens 60 and the seventh lens 70 are joined together using an adhesive.

[0531] The fifth lens 50 is made of glass. The fifth lens 50 has positive optical power. The lens surface 51 on the object side La of the fifth lens 50 has a convex shape, and the lens surface 52 on the image side Lb has a convex shape. The sixth lens 60 is made of resin. The sixth lens 60 has negative optical power. The lens surface 61 on the object side La of the sixth lens 60 has a concave shape, and the lens surface 62 on the image side Lb has a concave shape. The sixth lens 60 has aspherical shapes on both surfaces. The seventh lens 70 is made of resin. The seventh lens 70 has positive optical power. The lens surface 71 on the object side La of the seventh lens 70 has a convex shape, and the lens surface 72 on the image side Lb has a convex shape. The seventh lens 70 has aspherical shapes on both surfaces.

[0532] (Lens structure)

[0533] Figure 38 This is a diagram showing the data of the camera optical system 100 in Embodiment 7. The camera optical system 100 of this embodiment satisfies the conditional expressions (1) to (15) described in Embodiment 1.

[0534] In this embodiment,

[0535] ν21=23.261

[0536] ν22=56.219

[0537] f3 = 6.807

[0538] f4 = 45.666.

[0539] Therefore, ν21 = 23.261, satisfying condition (1) (1A). ν22 = 56.219, satisfying condition (2) (2A). |f3 / f4| = 0.149, satisfying condition (3).

[0540] In this embodiment,

[0541] ν21=23.261

[0542] ν22=56.219

[0543] Sag71=1.571

[0544] sd71 = 2.166.

[0545] Therefore, ν21 = 23.261, satisfying condition (1) (1A). ν22 = 56.219, satisfying condition (2) (2A). |Sag71 / sd71| = 0.726, satisfying condition (4).

[0546] In this embodiment,

[0547] Sag31 = -0.439

[0548] sd31 = 1.904.

[0549] Therefore, |Sag31 / sd31|=0.231, which satisfies condition (5).

[0550] In this embodiment,

[0551] f0 = 1.518

[0552] f34 = 6.958.

[0553] Therefore, f34 / f0 = 4.583, which satisfies condition (6).

[0554] In this embodiment,

[0555] f0 = 1.518

[0556] R61 = -12.209

[0557] R71 = 1.601.

[0558] Therefore, R61 / f0 = -8.042, satisfying condition (7). R71 / f0 = 1.054, satisfying condition (8).

[0559] In this embodiment,

[0560] R61 = -12.209

[0561] R62 = 1.601.

[0562] Therefore, (R61+R62) / (R61-R62) = 0.768, which satisfies condition (9).

[0563] In this embodiment,

[0564] f0 = 1.518

[0565] d0 = 18.000.

[0566] Therefore, d0 / f0 = 11.856, which satisfies condition (10).

[0567] In this embodiment,

[0568] R51 = 5.956

[0569] R52 = -4.656.

[0570] Therefore, condition (11) is satisfied.

[0571] In this embodiment,

[0572] ν6=23.261

[0573] ν7 = 56.219.

[0574] Therefore, ν6 = 23.261, satisfying condition (12). ν7 = 56.219, satisfying condition (13).

[0575] In this embodiment,

[0576] ω = 106.

[0577] Therefore, condition (14) is satisfied.

[0578] In this embodiment,

[0579] T1 = 1.000

[0580] f0 = 1.518.

[0581] Therefore, T1 / f0 = 0.659, which satisfies condition (15).

[0582] (Effects)

[0583] The camera optical system 100 of Embodiment 7 satisfies the same conditions (1) to (15) as Embodiment 1, and therefore can achieve the same effect as Embodiment 1.

[0584] Figure 39 It means Figure 37 A diagram of the spherical aberration of the camera optical system 100 shown. Figure 40 It means Figure 37 A diagram showing the magnification chromatic aberration of the camera optical system 100. Figure 41 It means Figure 37 A diagram showing astigmatism and distortion of the camera optical system 100. Figure 42 It means Figure 37 A diagram showing the lateral aberrations of the camera optical system 100.

[0585] like Figures 39-42 As shown, in the camera optical system 100 of this embodiment, spherical aberration, magnification chromatic aberration, astigmatism (distortion), lateral aberration, and resolution are corrected to an appropriate level.

[0586] Furthermore, this technology can adopt the following structure.

[0587] (Note 1)

[0588] A camera optical system, wherein,

[0589] From the object side towards the image side, it consists of the front group, aperture, and rear group in sequence.

[0590] The front group, arranged sequentially from the object side toward the image side, includes: a first group with negative optical power and a second group with positive optical power.

[0591] The second group includes a second group of first lenses and a second group of second lenses that are adjacent to the second group of first lenses on the image side and are disposed closest to the image side.

[0592] When the Abbe number of the first lens in the second group is set to ν21, the Abbe number of the second lens in the second group is set to ν22, the focal length of the first lens in the second group is set to f3, and the focal length of the second lens in the second group is set to f4, the following condition is satisfied:

[0593] ν21 < 30.000

[0594] 44.000 < ν22

[0595] 0.000 < |f3 / f4| < 0.500.

[0596] (Note 2)

[0597] According to the camera optical system described in Appendix 1, wherein,

[0598] When the depression of the object-side lens surface of the second group of first lenses is set to Sag31, and the effective radius of the object-side lens surface of the second group of first lenses is set to sd31, the following condition is satisfied:

[0599] 0.000 < |Sag31 / sd31| < 0.250.

[0600] (Note 3)

[0601] According to the camera optical system described in Appendix 1 or 2, wherein,

[0602] When the focal length of the entire lens system is set to f0, and the focal length of the second group is set to f34, the following condition is satisfied:

[0603] 2.000 < f34 / f0 < 6.000.

[0604] (Note 4)

[0605] The camera optical system according to any one of Appendices 1 to 3, wherein,

[0606] When the focal length of the entire lens system is set to f0, and the radius of curvature of the lens surface on the object side of the first lens in the second group is set to R31, the following condition is satisfied:

[0607] 8.000 < |R31 / f0|.

[0608] (Note 5)

[0609] The camera optical system according to any one of Appendices 1 to 4, wherein,

[0610] The second group of first lenses has positive optical power.

[0611] The object-side lens surface of the second group of first lenses has a convex shape near the optical axis and a concave shape around the periphery.

[0612] The lens surface on the image side of the first lens in the second group has a convex shape.

[0613] (Note 6)

[0614] The camera optical system according to any one of Appendices 1 to 5, wherein,

[0615] The first lens of the second group and the second lens of the second group are made of resin.

[0616] (Note 7)

[0617] The camera optical system according to any one of Appendices 1 to 6, wherein,

[0618] When the focal length of the entire lens system is set to f0 and the total length of the entire lens system is set to d0, the following condition is satisfied:

[0619] 10.000 < d0 / f0 < 15.000.

[0620] (Postscript 8)

[0621] The camera optical system according to any one of Appendices 1 to 7, wherein,

[0622] The first group consists of a first lens and a second lens, arranged sequentially from the object side towards the image side.

[0623] The second group consists of a third lens (which serves as the first lens of the second group) and a fourth lens (which serves as the second lens of the second group) arranged sequentially from the object side towards the image side.

[0624] The rear group consists of a fifth lens, a sixth lens, and a seventh lens, arranged sequentially from the object side toward the image side.

[0625] (Note 9)

[0626] According to the camera optical system described in Appendix 8, wherein,

[0627] The fifth lens is made of glass.

[0628] When the radius of curvature of the object-side lens surface of the fifth lens is set to R51, and the radius of curvature of the image-side lens surface of the fifth lens is set to R52, the following condition is satisfied:

[0629] |R52| < |R51|.

[0630] (Postscript 10)

[0631] According to the camera optical system described in Appendix 8 or 9, wherein,

[0632] When the Abbe number of the sixth lens is set to ν6 and the Abbe number of the seventh lens is set to ν7, the following condition is satisfied:

[0633] ν6 < 30.000

[0634] 50,000 < ν7.

[0635] (Postscript 11)

[0636] A camera device, comprising:

[0637] The camera optical system described in any one of Appendices 1 to 10; and

[0638] The camera element is disposed on the image side of the camera optical system.

Claims

1. A camera optical system, characterized in that, From the object side towards the image side, it consists of the front group, aperture, and rear group in sequence. The front group, arranged sequentially from the object side toward the image side, comprises: a first group having negative optical power and a second group having positive optical power. The second group includes: a second group of first lenses, and a second group of second lenses adjacent to the second group of first lenses on the image side and disposed closest to the image side. When the Abbe number of the first lens in the second group is set to ν21, the Abbe number of the second lens in the second group is set to ν22, the focal length of the first lens in the second group is set to f3, and the focal length of the second lens in the second group is set to f4, the following condition is satisfied: ν21 < 30.000 44.000 < ν22 0.000 < |f3 / f4| < 0.

500.

2. The camera optical system according to claim 1, characterized in that, When the depression of the object-side lens surface of the second group of first lenses is set to Sag31, and the effective radius of the object-side lens surface of the second group of first lenses is set to sd31, the following condition is satisfied: 0.000 < |Sag31 / sd31| < 0.

250.

3. The camera optical system according to claim 1 or 2, characterized in that, When the focal length of the entire lens system is set to f0, and the focal length of the second group is set to f34, the following condition is satisfied: 2.000 < f34 / f0 < 6.

000.

4. The camera optical system according to claim 1, characterized in that, When the focal length of the entire lens system is set to f0, and the radius of curvature of the lens surface on the object side of the second group of first lenses is set to R31, the following condition is satisfied: 8.000 < |R31 / f0|.

5. The camera optical system according to claim 1, characterized in that, The second group of first lenses has positive optical power. The lens surface on the object side of the second group of first lenses has a convex shape near the optical axis and a concave shape around the periphery. The lens surface on the image side of the first lens in the second group has a convex shape.

6. The camera optical system according to claim 1, characterized in that, The first lens of the second group and the second lens of the second group are made of resin.

7. The camera optical system according to claim 1, characterized in that, When the focal length of the entire lens system is set to f0 and the total length of the entire lens system is set to d0, the following condition is satisfied: 10.000 < d0 / f0 < 15.

000.

8. The camera optical system according to claim 1, characterized in that, The first group consists of a first lens and a second lens sequentially from the object side toward the image side. The second group, moving from the object side towards the image side, consists of a third lens (serving as the first lens of the second group) and a fourth lens (serving as the second lens of the second group). The rear group consists of a fifth lens, a sixth lens, and a seventh lens, arranged sequentially from the object side toward the image side.

9. The camera optical system according to claim 8, characterized in that, The fifth lens is made of glass. When the radius of curvature of the object-side lens surface of the fifth lens is set to R51, and the radius of curvature of the image-side lens surface of the fifth lens is set to R52, the following condition is satisfied: |R52| < |R51|.

10. The camera optical system according to claim 8 or 9, characterized in that, When the Abbe number of the sixth lens is set to ν6 and the Abbe number of the seventh lens is set to ν7, the following condition is satisfied: ν6 < 30.000 50,000 < ν7.

11. A camera device, characterized in that, include: The camera optical system as described in claim 1; as well as A camera element is disposed on the image side of the camera optical system.

Images