Variable magnification imaging optical system

Abstract

According to the present application, there is provided a variable magnification imaging optical system which increases a variable magnification ratio while suppressing a center of gravity shift caused by zooming, achieves miniaturization and light weight, and has good optical performance from infinity to a close range in the entire zoom range. The variable magnification imaging optical system is characterized by including, in order from an object side, a first front lens group having positive refractive power, a second front lens group having negative refractive power, an intermediate group, and a subsequent group, the first front lens group has a first lens group at a position closest to the object side, an aperture stop is disposed at a position closer to an image side than the second front lens group, the second front lens group has a lens group having the strongest negative refractive power among the lens groups disposed at a position closer to the object side than the aperture stop, and a specific conditional expression is satisfied.

Description

Technical Field

[0001] This invention relates to a zoom imaging optical system, which is used in digital cameras, video cameras and other imaging devices, and is suitable for imaging optical systems. Background Technology

[0002] In recent years, mirrorless cameras and camcorders have continued to develop, and high-performance cameras have been integrated into smartphones and mobile data terminals. In order to differentiate digital cameras and camcorders from these mobile devices, the demand for zoom lenses in the super telephoto range has been increasing.

[0003] Furthermore, the increasing pixel count of image sensors in digital cameras and camcorders in recent years has further increased the demand for high-performance and compact, lightweight imaging optical systems.

[0004] Patent documents 1 to 3 describe examples of zoom imaging optical systems with a half field of view of approximately 3 degrees or less at the far end.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-167749

[0006] Patent Document 2: Japanese Patent 7570685

[0007] Patent Document 3: Japanese Patent Application Publication No. 2019-020450

[0008] In super telephoto zoom lenses with narrow field of view at the telephoto end, to improve ease of use as a zoom lens, it is necessary to balance three points: achieving the largest possible zoom ratio, miniaturization for improved portability, and imaging performance. Furthermore, with super telephoto zoom lenses having a large diameter lens mounted on the object side, the center of gravity tends to be located on the object side. Therefore, if the heavy lens group is moved significantly, the shift in the center of gravity tends to increase, leading to many adverse effects in applications such as dynamic image photography using gimbals.

[0009] The optical system described in Patent Document 1 is an example of a super telephoto zoom lens with a fixed total length. Although it suppresses various aberrations throughout the zoom area and has high imaging performance, the zoom ratio of the embodiment with a half field of view of about 3 degrees is also small, less than 2. From the viewpoint of miniaturization, this is insufficient if the zoom ratio and the field of view at the telephoto end are taken into account.

[0010] The optical system described in Patent Document 2 is an example of a super telephoto zoom where the total length of the first lens group extending toward the object side is variable when zooming toward the telephoto side. It has a large zoom ratio and a short total optical length at the wide-angle end, achieving miniaturization. However, the zoom movement of the first lens group is about 100mm, which increases the shift in the center of gravity, which is a disadvantage.

[0011] The optical system described in Patent Document 3 includes an embodiment of a super telephoto zoom lens with a fixed total length, but from the viewpoint of miniaturization, there is room for improvement if the zoom ratio and the field of view at the telephoto end are taken into account. Summary of the Invention

[0012] The present invention was made in view of this problem, and its purpose is to provide a zoom imaging optical system that increases the zoom ratio while suppressing the center of gravity shift caused by zooming, achieving miniaturization and weight reduction, and having good optical performance throughout the zoom range from infinity to near.

[0013] To address the aforementioned issues, a zoom imaging optical system is provided, comprising a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 comprises one or two lens groups and has positive refractive power overall. The second front lens group GF2 comprises one or more lens groups and has negative refractive power overall. The intermediate group GM comprises one or more lens groups. The first front lens group GF1 has a first lens group G1 located closest to the object side. An aperture stop S is positioned closer to the image side than the second front lens group GF2. The second front lens group GF2 has the lens group with the strongest negative refractive power among the lens groups positioned closer to the object side than the aperture stop S. The spacing between adjacent lens groups changes during zooming or focusing. When zooming from the wide-angle end to the telephoto end, when focusing on an object at infinity, the lens group with the strongest negative refractive power in the lens group constituting the second front lens group GF2 moves towards the image side, satisfying the following condition.

[0014] (1) 2.50 < fT / fF1 < 11.00

[0015] (2) 0.15 < LiT / fT < 0.70

[0016] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0017] fF1: Focal length of the first front lens group GF1 at infinity.

[0018] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0019] Invention Effects

[0020] According to the present invention, a zoom imaging optical system is provided, which increases the zoom ratio while suppressing the center of gravity shift caused by zooming, thereby achieving miniaturization and weight reduction, and possessing good optical performance throughout the entire zoom range from infinity to near. Attached Figure Description

[0021] Figure 1This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 1 of the zoom imaging optical system of the present invention.

[0022] Figure 2 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 1 of the zoom imaging optical system of the present invention.

[0023] Figure 3 This is a longitudinal aberration diagram of the intermediate focal length at infinity when focusing, according to Embodiment 1 of the zoom imaging optical system of the present invention.

[0024] Figure 4 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 1 of the zoom imaging optical system of the present invention.

[0025] Figure 5 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 1 of the zoom imaging optical system of the present invention.

[0026] Figure 6 This is a lateral aberration diagram of the intermediate focal length at infinity when focusing, according to Embodiment 1 of the zoom imaging optical system of the present invention.

[0027] Figure 7 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 1 of the zoom imaging optical system of the present invention.

[0028] Figure 8 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention when focusing at a distance of 4.0m from the object.

[0029] Figure 9 This is a lateral aberration diagram of an object at a distance of 4.0m at the intermediate focal length, as described in Embodiment 1 of the zoom imaging optical system of the present invention.

[0030] Figure 10 This is a lateral aberration diagram of the telescope at a distance of 4.0m when focusing, according to Embodiment 1 of the zoom imaging optical system of the present invention.

[0031] Figure 11 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 1 of the zoom imaging optical system of the present invention.

[0032] Figure 12 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0033] Figure 13This is a lateral aberration diagram of the zoom imaging optical system of the present invention, when focusing at infinity at the telescope end relative to a shake angle of 0.3 degrees, with vibration stabilization.

[0034] Figure 14 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 2 of the zoom imaging optical system of the present invention.

[0035] Figure 15 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0036] Figure 16 This is a longitudinal aberration diagram of the intermediate focal length at infinity when focusing, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0037] Figure 17 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0038] Figure 18 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0039] Figure 19 This is a lateral aberration diagram of the intermediate focal length at infinity when focusing, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0040] Figure 20 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0041] Figure 21 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 4.5m when focusing.

[0042] Figure 22 This is a lateral aberration diagram of an object at a distance of 4.5m at the intermediate focal length, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0043] Figure 23 This is a lateral aberration diagram of the telescope at a distance of 4.5m when focusing, according to Embodiment 2 of the zoom imaging optical system of the present invention.

[0044] Figure 24 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 2 of the zoom imaging optical system of the present invention.

[0045] Figure 25This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0046] Figure 26 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 2 of the zoom imaging optical system of the present invention.

[0047] Figure 27 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 3 of the zoom imaging optical system of the present invention.

[0048] Figure 28 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0049] Figure 29 This is a longitudinal aberration diagram of the intermediate focal length at infinity when focusing, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0050] Figure 30 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0051] Figure 31 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0052] Figure 32 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0053] Figure 33 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0054] Figure 34 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 6.0m when focusing.

[0055] Figure 35 This is a lateral aberration diagram of an object at a distance of 6.0m at the intermediate focal length, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0056] Figure 36 This is a lateral aberration diagram of the telescope at a distance of 6.0m from the object being focused, according to Embodiment 3 of the zoom imaging optical system of the present invention.

[0057] Figure 37This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 3 of the zoom imaging optical system of the present invention.

[0058] Figure 38 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0059] Figure 39 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 3 of the zoom imaging optical system of the present invention.

[0060] Figure 40 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 4 of the zoom imaging optical system of the present invention.

[0061] Figure 41 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0062] Figure 42 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0063] Figure 43 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 4 of the zoom imaging optical system of the present invention.

[0064] Figure 44 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0065] Figure 45 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0066] Figure 46 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0067] Figure 47 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention when focusing at a distance of 5.0m from the object.

[0068] Figure 48 This is a lateral aberration diagram of an object at a distance of 5.0m at the intermediate focal length, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0069] Figure 49This is a lateral aberration diagram of the object at the telescope at a distance of 5.0m, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0070] Figure 50 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 4 of the zoom imaging optical system of the present invention.

[0071] Figure 51 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees.

[0072] Figure 52 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 4 of the zoom imaging optical system of the present invention.

[0073] Figure 53 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 5 of the zoom imaging optical system of the present invention.

[0074] Figure 54 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0075] Figure 55 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0076] Figure 56 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 5 of the zoom imaging optical system of the present invention.

[0077] Figure 57 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0078] Figure 58 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0079] Figure 59 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0080] Figure 60 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 4.0m when focusing.

[0081] Figure 61This is a lateral aberration diagram of an object at a distance of 4.0m at the intermediate focal length, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0082] Figure 62 This is a lateral aberration diagram of the telescope at a distance of 4.0m when focusing, according to Embodiment 5 of the zoom imaging optical system of the present invention.

[0083] Figure 63 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 5 of the zoom imaging optical system of the present invention.

[0084] Figure 64 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees during vibration stabilization.

[0085] Figure 65 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 5 of the zoom imaging optical system of the present invention.

[0086] Figure 66 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 6 of the zoom imaging optical system of the present invention.

[0087] Figure 67 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0088] Figure 68 This is a longitudinal aberration diagram of infinity focusing at the intermediate focal length, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0089] Figure 69 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 6 of the zoom imaging optical system of the present invention.

[0090] Figure 70 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0091] Figure 71 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0092] Figure 72 This is a lateral aberration diagram of the telescope at infinity focusing, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0093] Figure 73This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 4.3m when focusing.

[0094] Figure 74 This is a lateral aberration diagram of an object at a distance of 4.3m at the intermediate focal length, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0095] Figure 75 This is a lateral aberration diagram of the object at the telescope at a distance of 4.3m, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0096] Figure 76 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 6 of the zoom imaging optical system of the present invention.

[0097] Figure 77 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0098] Figure 78 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a jitter angle of 0.3 degrees, according to Embodiment 6 of the zoom imaging optical system of the present invention.

[0099] Figure 79 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 7 of the zoom imaging optical system of the present invention.

[0100] Figure 80 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0101] Figure 81 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0102] Figure 82 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 7 of the zoom imaging optical system of the present invention.

[0103] Figure 83 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0104] Figure 84 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0105] Figure 85This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 7 of the zoom imaging optical system of the present invention.

[0106] Figure 86 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 4.2m when focusing.

[0107] Figure 87 This is a lateral aberration diagram of an object at a distance of 4.2m at the intermediate focal length, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0108] Figure 88 This is a lateral aberration diagram of the telescope at a distance of 4.2m from the object being focused, according to Embodiment 7 of the zoom imaging optical system of the present invention.

[0109] Figure 89 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 7 of the zoom imaging optical system of the present invention.

[0110] Figure 90 This is a lateral aberration diagram of the zoom imaging optical system of the present invention during infinity focusing at the intermediate focal length relative to a shake angle of 0.3 degrees, as described in Embodiment 7 of the present invention.

[0111] Figure 91 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 7 of the zoom imaging optical system of the present invention.

[0112] Figure 92 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 8 of the zoom imaging optical system of the present invention.

[0113] Figure 93 This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0114] Figure 94 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0115] Figure 95 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 8 of the zoom imaging optical system of the present invention.

[0116] Figure 96 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0117] Figure 97This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0118] Figure 98 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 8 of the zoom imaging optical system of the present invention.

[0119] Figure 99 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention when focusing at a distance of 3.5m from the object.

[0120] Figure 100 This is a lateral aberration diagram of an object at a distance of 3.5m at the intermediate focal length, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0121] Figure 101 This is a lateral aberration diagram of the telescope at a distance of 3.5m when focusing, according to Embodiment 8 of the zoom imaging optical system of the present invention.

[0122] Figure 102 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 8 of the zoom imaging optical system of the present invention.

[0123] Figure 103 This is a lateral aberration diagram of the zoom imaging optical system of the present invention during infinity focusing at the intermediate focal length relative to a shake angle of 0.3 degrees, as described in Embodiment 8 of the present invention.

[0124] Figure 104 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 8 of the zoom imaging optical system of the present invention.

[0125] Figure 105 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 9 of the zoom imaging optical system of the present invention.

[0126] Figure 106 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0127] Figure 107 This is a longitudinal aberration diagram of infinity focusing at the intermediate focal length, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0128] Figure 108 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 9 of the zoom imaging optical system of the present invention.

[0129] Figure 109This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0130] Figure 110 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0131] Figure 111 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 9 of the zoom imaging optical system of the present invention.

[0132] Figure 112 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 2.6m when focusing.

[0133] Figure 113 This is a lateral aberration diagram of an object at a distance of 2.6m at the intermediate focal length, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0134] Figure 114 This is a lateral aberration diagram of the telescope at a distance of 2.6m when focusing, according to Embodiment 9 of the zoom imaging optical system of the present invention.

[0135] Figure 115 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 9 of the zoom imaging optical system of the present invention.

[0136] Figure 116 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0137] Figure 117 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 9 of the zoom imaging optical system of the present invention.

[0138] Figure 118 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0139] Figure 119 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0140] Figure 120 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 10 of the zoom imaging optical system of the present invention.

[0141] Figure 121This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0142] Figure 122 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 10 of the zoom imaging optical system of the present invention.

[0143] Figure 123 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 10 of the zoom imaging optical system of the present invention.

[0144] Figure 124 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0145] Figure 125 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.5m when focusing.

[0146] Figure 126 This is a lateral aberration diagram of an object at a distance of 3.5m at the intermediate focal length, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0147] Figure 127 This is a lateral aberration diagram of the telescope at a distance of 3.5m when focusing, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0148] Figure 128 This is a lateral aberration diagram of the wide-angle end when focusing at infinity relative to a shake angle of 0.3 degrees, as described in Embodiment 10 of the zoom imaging optical system of the present invention.

[0149] Figure 129 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0150] Figure 130 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 10 of the zoom imaging optical system of the present invention.

[0151] Figure 131 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 11 of the zoom imaging optical system of the present invention.

[0152] Figure 132 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 11 of the zoom imaging optical system of the present invention.

[0153] Figure 133This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 11 of the zoom imaging optical system of the present invention.

[0154] Figure 134 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 11 of the zoom imaging optical system of the present invention.

[0155] Figure 135 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 11 of the zoom imaging optical system of the present invention.

[0156] Figure 136 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 11 of the zoom imaging optical system of the present invention.

[0157] Figure 137 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 11 of the zoom imaging optical system of the present invention.

[0158] Figure 138 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.2m when focusing.

[0159] Figure 139 This is a lateral aberration diagram of an object at a distance of 3.2m at the intermediate focal length, according to Embodiment 11 of the zoom imaging optical system of the present invention.

[0160] Figure 140 This is a lateral aberration diagram of the telescope at a distance of 3.2m from the object being focused, according to Embodiment 11 of the zoom imaging optical system of the present invention.

[0161] Figure 141 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 11 of the zoom imaging optical system of the present invention.

[0162] Figure 142 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0163] Figure 143 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the telescope end with vibration stabilization relative to a jitter angle of 0.3 degrees, according to Embodiment 11 of the present invention.

[0164] Figure 144 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 12 of the zoom imaging optical system of the present invention.

[0165] Figure 145This is a longitudinal aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0166] Figure 146 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0167] Figure 147 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 12 of the zoom imaging optical system of the present invention.

[0168] Figure 148 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0169] Figure 149 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0170] Figure 150 This is a lateral aberration diagram of the telescope at infinity focusing, according to Embodiment 12 of the zoom imaging optical system of the present invention.

[0171] Figure 151 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention when focusing at a distance of 2.8m from the object.

[0172] Figure 152 This is a lateral aberration diagram of an object at a distance of 2.8m at the intermediate focal length, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0173] Figure 153 This is a lateral aberration diagram of the telescope at a distance of 2.8m when focusing, according to Embodiment 12 of the zoom imaging optical system of the present invention.

[0174] Figure 154 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 12 of the zoom imaging optical system of the present invention.

[0175] Figure 155 This is a lateral aberration diagram of the zoom imaging optical system of the present invention during infinity focusing at the intermediate focal length relative to a shake angle of 0.3 degrees, as described in Embodiment 12 of the present invention.

[0176] Figure 156 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 12 of the zoom imaging optical system of the present invention.

[0177] Figure 157This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 13 of the zoom imaging optical system of the present invention.

[0178] Figure 158 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0179] Figure 159 This is a longitudinal aberration diagram of infinity focusing at the intermediate focal length, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0180] Figure 160 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 13 of the zoom imaging optical system of the present invention.

[0181] Figure 161 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0182] Figure 162 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0183] Figure 163 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 13 of the zoom imaging optical system of the present invention.

[0184] Figure 164 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention when focusing at a distance of 3.5m from the object.

[0185] Figure 165 This is a lateral aberration diagram of an object at a distance of 3.5m at the intermediate focal length, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0186] Figure 166 This is a lateral aberration diagram of the telescope at a distance of 3.5m when focusing, according to Embodiment 13 of the zoom imaging optical system of the present invention.

[0187] Figure 167 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 13 of the zoom imaging optical system of the present invention.

[0188] Figure 168 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length with vibration stabilization relative to a shake angle of 0.3 degrees, according to Embodiment 13 of the present invention.

[0189] Figure 169This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 13 of the zoom imaging optical system of the present invention.

[0190] Figure 170 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 14 of the zoom imaging optical system of the present invention.

[0191] Figure 171 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0192] Figure 172 This is a longitudinal aberration diagram of the intermediate focal length at infinity when focusing, according to Embodiment 14 of the zoom imaging optical system of the present invention.

[0193] Figure 173 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 14 of the zoom imaging optical system of the present invention.

[0194] Figure 174 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0195] Figure 175 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0196] Figure 176 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 14 of the zoom imaging optical system of the present invention.

[0197] Figure 177 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.1m when focusing.

[0198] Figure 178 This is a lateral aberration diagram of an object at a distance of 3.1m at the intermediate focal length, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0199] Figure 179 This is a lateral aberration diagram of the object at the telescope at a distance of 3.1m, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0200] Figure 180 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 14 of the zoom imaging optical system of the present invention.

[0201] Figure 181This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length with a shake angle of 0.3 degrees.

[0202] Figure 182 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 14 of the zoom imaging optical system of the present invention.

[0203] Figure 183 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0204] Figure 184 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 15 of the zoom imaging optical system of the present invention.

[0205] Figure 185 This is a longitudinal aberration diagram of infinity focusing at the intermediate focal length, as described in Embodiment 15 of the zoom imaging optical system of the present invention.

[0206] Figure 186 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0207] Figure 187 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 15 of the zoom imaging optical system of the present invention.

[0208] Figure 188 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 15 of the zoom imaging optical system of the present invention.

[0209] Figure 189 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0210] Figure 190 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.2m when focusing.

[0211] Figure 191 This is a lateral aberration diagram of an object at a distance of 3.2m at the intermediate focal length, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0212] Figure 192 This is a lateral aberration diagram of the telescope at a distance of 3.2m when focusing, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0213] Figure 193This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 15 of the zoom imaging optical system of the present invention.

[0214] Figure 194 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0215] Figure 195 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 15 of the zoom imaging optical system of the present invention.

[0216] Figure 196 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 16 of the zoom imaging optical system of the present invention.

[0217] Figure 197 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0218] Figure 198 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0219] Figure 199 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 16 of the zoom imaging optical system of the present invention.

[0220] Figure 200 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0221] Figure 201 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0222] Figure 202 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 16 of the zoom imaging optical system of the present invention.

[0223] Figure 203 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.3m when focusing.

[0224] Figure 204 This is a lateral aberration diagram of an object at a distance of 3.3m at the intermediate focal length, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0225] Figure 205This is a lateral aberration diagram of the telescope at a distance of 3.3m when focusing, according to Embodiment 16 of the zoom imaging optical system of the present invention.

[0226] Figure 206 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 16 of the zoom imaging optical system of the present invention.

[0227] Figure 207 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0228] Figure 208 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 16 of the zoom imaging optical system of the present invention.

[0229] Figure 209 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 17 of the zoom imaging optical system of the present invention.

[0230] Figure 210 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0231] Figure 211 This is a longitudinal aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0232] Figure 212 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 17 of the zoom imaging optical system of the present invention.

[0233] Figure 213 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0234] Figure 214 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0235] Figure 215 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 17 of the zoom imaging optical system of the present invention.

[0236] Figure 216 This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.2m when focusing.

[0237] Figure 217This is a lateral aberration diagram of an object at a distance of 3.2m at the intermediate focal length, according to Embodiment 17 of the zoom imaging optical system of the present invention.

[0238] Figure 218 This is a lateral aberration diagram of the object at the telescope at a distance of 3.2m, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0239] Figure 219 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 17 of the zoom imaging optical system of the present invention.

[0240] Figure 220 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0241] Figure 221 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 17 of the zoom imaging optical system of the present invention.

[0242] Figure 222 This is a lens structure diagram of the wide-angle end when focusing at infinity, according to Embodiment 18 of the zoom imaging optical system of the present invention.

[0243] Figure 223 This is a longitudinal aberration diagram of infinity focusing at the wide-angle end, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0244] Figure 224 This is a longitudinal aberration diagram of infinity focusing at the intermediate focal length, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0245] Figure 225 This is a longitudinal aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 18 of the zoom imaging optical system of the present invention.

[0246] Figure 226 This is a lateral aberration diagram of the wide-angle end at infinity focusing, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0247] Figure 227 This is a lateral aberration diagram of the intermediate focal length at infinity focusing, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0248] Figure 228 This is a lateral aberration diagram of the telephoto end when focusing at infinity, according to Embodiment 18 of the zoom imaging optical system of the present invention.

[0249] Figure 229This is a lateral aberration diagram of the wide-angle end of the zoom imaging optical system of the present invention at a distance of 3.3m when focusing.

[0250] Figure 230 This is a lateral aberration diagram of an object at a distance of 3.3m at the intermediate focal length, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0251] Figure 231 This is a lateral aberration diagram of the telescope at a distance of 3.3m from the object being focused, according to Embodiment 18 of the zoom imaging optical system of the present invention.

[0252] Figure 232 This is a lateral aberration diagram of the wide-angle infinity focusing relative to a shake angle of 0.3 degrees, as described in Embodiment 18 of the zoom imaging optical system of the present invention.

[0253] Figure 233 This is a lateral aberration diagram of the zoom imaging optical system of the present invention, which is used for focusing at infinity at the intermediate focal length relative to a shake angle of 0.3 degrees when the system is shaken.

[0254] Figure 234 This is a lateral aberration diagram of the telephoto end when focusing at infinity relative to a shake angle of 0.3 degrees, according to Embodiment 18 of the zoom imaging optical system of the present invention. Detailed Implementation

[0255] The following describes a zoom imaging optical system according to an embodiment of the present invention. Furthermore, the following description of an example of the optical system of the present invention provides an illustration. The present invention is not limited to this embodiment without departing from its spirit, and modifications can be made within the scope of the spirit. For example, modifications can be made such as making the surface formed by a sphere or plane aspherical, using a crystalline material other than optical glass or a plastic, or applying an anti-reflective coating or a functional film / structure with hydrophobic or oleophobic properties to the lens surface. The description will be conducted with the object side as the front side and the image side as the rear side.

[0256] In this invention, when counting the number of lenses, unless otherwise specified, a single lens is counted as one piece. In the case of a bonded lens, each single lens constituting the bonded lens is counted as one piece. For example, if it is a bonded lens including a convex lens and a concave lens, it is counted as two pieces. Regarding lenses that have an aberration correction effect due to resin or the like on a lens that serves as a substrate such as a composite aspherical surface, the substrate and the attached shape or structure are considered as one unit and counted as one lens. The bonding resin layer of a bonded lens is not counted as a lens. Even if the bonding resin of the bonded lens has an aberration correction effect, it is considered as a structure attached to any of the bonded lenses, and this resin portion is not counted as one lens. Parallel planar plates such as filters that do not have refractive power are also not counted as lenses.

[0257] Furthermore, in this invention, a meniscus lens shape is defined as a lens whose object-side and image-side surfaces are composed of curved surfaces with radii of curvature having the same sign. For example, a concave meniscus lens with the convex surface facing the object side is a lens in which the radii of curvature of both the object-side and image-side surfaces are positive, and the radius of curvature of the image-side surface is smaller. Additionally, in the case of aspherical lenses, the lens shape is determined based on the paraxial radius of curvature.

[0258] In this application, the distinction between lens groups is defined by using the surfaces whose spacing on the optical axis changes due to zooming or focusing as the distinction between each lens group. Therefore, when the aperture stop S moves independently due to zooming or focusing, the aperture stop S is considered as a lens group.

[0259] In the following description of the embodiments, the refractive indices of the materials relative to the g-line (wavelength 435.8 nm), F-line (486.1 nm), d-line (587.6 nm), and C-line (656.3 nm) are respectively denoted as Ng, NF, Nd, and NC. Furthermore, the Abbe number νd, partial dispersion ratio PgF, and anomalous dispersion ΔPgF are expressed as...

[0260] νd = (Nd-1) / (NF-NC)

[0261] PgF = (Ng - NF) / (NF - NC)

[0262] ΔPgF = PgF-0.64833+0.00180×νd.

[0263] Furthermore, unless otherwise specified in this document, the term "refractive index" refers to the refractive index of the d-line.

[0264] In the description of embodiments of the present invention, although the heights of the on-axis edge rays and off-axis principal rays are described, they essentially represent the distance from the optical axis, thus avoiding the concept of positive or negative. The optical axis is set to 0, and the direction of separation from that point is treated as positive. The height of the ray is expressed by the magnitude of the distance from the optical axis. Furthermore, in the conditional expressions of the present invention, unless otherwise specified, the on-axis edge ray is defined as the ray contained in the on-axis beam when the aperture stop is open, which passes through the aperture stop S from the optical axis at its maximum height. Similarly, regarding the off-axis principal rays, the ray that passes through the center of the aperture stop S among the off-axis rays reaching the maximum image height is defined as the off-axis principal ray.

[0265] In super telephoto zoom lenses like those of the present invention, achieving a shorter overall length without reducing the zoom ratio or optical performance is an indispensable element for achieving miniaturization and lightweight design. Reducing the weight of the heavy first lens group G1, suppressing movement, and minimizing changes in the center of gravity caused by zooming are also important.

[0266] Furthermore, suppressing chromatic aberration is an indispensable element for achieving high performance in super telephoto zoom lenses such as those of the present invention. There are two types of chromatic aberration: on-axis chromatic aberration and magnification chromatic aberration. To suppress these two types of chromatic aberration throughout the zoom range, the selection of appropriate glass materials corresponding to changes in optical power configuration is crucial.

[0267] Typically, the magnification chromatic aberration of an optical system composed of thin-walled lenses is given as the sum of the individual lenses by the following formula (refer to Formula 1), which can be considered as follows.

[0268] If a lens with positive refractive power is positioned closer to the object than the aperture stop, the peripheral light beam passing through the lens passes through a quadrant opposite to the imaging position. In the case of conventional optical glass, due to the characteristics of dispersion, the longer the wavelength, the lower the image height, and the C-line is observed as an under-direction chromatic aberration. Similarly, if a lens with negative refractive power is positioned closer to the object than the aperture stop, the opposite phenomenon occurs. Furthermore, if a lens is positioned closer to the image side than the aperture stop, the peripheral light beam passing through the lens and the imaging position pass through the same quadrant, thus exhibiting the opposite phenomenon to the case where the lens is positioned closer to the object than the aperture stop.

[0269] (Reference Formula 1) Σ(h•hb•φ / ν)

[0270] h: Height of the ray at the upper edge of the axis

[0271] hb: Off-axis principal ray height

[0272] φ: Refractive power

[0273] ν: Abbe number

[0274] Additionally, an on-axis edge ray is defined as a ray that passes through the aperture stop at its maximum height from the optical axis among the rays included in the on-axis beam, while a principal ray is defined as a ray that passes through the center of the aperture stop.

[0275] Similarly, the on-axis chromatic aberration of an optical system composed of thin-walled lenses is given as the sum of the individual lenses below (refer to Equation 2), and can be considered as follows.

[0276] (Reference Formula 2) Σ(h•h•φ / ν)

[0277] h: Height of the ray at the upper edge of the axis

[0278] φ: Refractive power

[0279] ν: Abbe number

[0280] Additionally, on-axis edge rays are defined as rays that pass through the aperture stop at maximum height from the optical axis within the rays included in an on-axis beam.

[0281] Regarding Equation 2, if we consider the height of the on-axis edge ray, the higher the position of the on-axis edge ray relative to the effective diameter of the lens, the greater the amount of on-axis chromatic aberration. Conversely, if the lens passes at a lower position of the on-axis edge ray height, the amount of on-axis chromatic aberration decreases. Therefore, in order to suppress on-axis chromatic aberration and magnification chromatic aberration throughout the zoom range, it is necessary to appropriately select the glass material based on the changes in the ray height of the on-axis edge ray and the off-axis principal ray during zooming.

[0282] In the case of a lens where the first lens group G1 is fixed or has a small amount of movement during zooming, as in the present invention, in order to increase the total optical length relative to the focal length on the wide-angle side, it becomes an inverse focal type with an asymmetrical refractive power configuration relative to the aperture stop. On the other hand, in order to shorten the total optical length relative to the focal length on the telephoto side, it becomes an asymmetrical refractive power configuration relative to the telephoto aperture stop. As a result, over-direction chromatic aberration occurs in the C-line on the wide-angle side, and under-direction chromatic aberration occurs in the C-line on the telephoto side. Therefore, in order to reduce chromatic aberration across the entire wavelength, a converging method such as collecting the g-line and C-line is often used. In this case, when the difference in imaging magnification between the g-line and C-line and other wavelengths is large, a secondary spectrum with colors such as purplish-red appears on the outline of the subject, which is not preferable. Therefore, it is effective to use a glass material with anomalous dispersion in the correction of the secondary spectrum.

[0283] As can be seen from the numerical embodiments or the structural diagrams of various embodiments, the zoom imaging optical system involved in the present invention includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes one or two lens groups and has positive refractive power as a whole. The second front lens group GF2 includes one or more lens groups and has negative refractive power as a whole. The intermediate group GM includes one or more lens groups.

[0284] The first anterior lens group GF1 has positive refractive power and a converging effect on light rays. Therefore, increasing the refractive power of the first anterior lens group GF1 allows light rays to converge over a shorter distance, contributing to a shorter overall length. On the other hand, excessive refractive power increases aberrations generated in the first anterior lens group GF1, leading to a decrease in optical performance. By appropriately setting the refractive power of the first anterior lens group GF1 and correcting the aberrations generated in the first anterior lens group GF1 in the optical system from the second anterior lens group GF2 onwards, a balance can be struck between shortening the overall length and maintaining good optical performance.

[0285] The first front lens group GF1 can be composed of a single lens group, but by composing it into two lens groups and moving the image-side lens group towards the object side when zooming from the wide-angle end to the telephoto end, the refractive power of the first front lens group GF1 can be weakened on the telephoto side, which helps to improve the zoom effect. In the case of a super telephoto zoom lens with a fixed overall length, the zoom ratio is not easily increased because the amount of movement of the group (zoom unit) that has the main zoom effect is limited. However, by composing the first front lens group GF1 into two lens groups and sharing the zoom effect, the zoom ratio can be increased.

[0286] The second front lens group GF2 has negative refractive power as a whole and is composed of more than one lens group. The lens group with the strongest negative refractive power undertakes the main magnification effect by moving towards the image side when zooming from the wide-angle end to the telephoto end. Furthermore, since the second front lens group GF2 is composed of multiple lens groups, it can suppress aberration changes during zooming by moving along different trajectories, especially suppressing changes in image plane curvature.

[0287] The intermediate group GM, which includes one or more lens groups, has the function of correcting image plane variations along with zoom. If the zoom ratio is increased, the aberration variation in the zoom intermediate region becomes larger, but it can be effectively corrected by moving multiple lens groups along different trajectories during zoom.

[0288] The subsequent GR group compensates for the image plane of the light rays passing through the intermediate GM group, ensuring they are imaged at a specified image height. From the viewpoint of miniaturization of the optical system, the subsequent GR group preferably has negative refractive power. This is because it has the effect of further shifting the principal point position on the object side towards the object side, thus reducing the telephoto ratio (the ratio of focal length to total optical length). In the subsequent GR group, a glass material with positive anomalous dispersion is used in the concave lens, and a glass material with negative anomalous dispersion is used in the convex lens, thereby producing an effect of correcting the g-line in the overdirection, which can correct chromatic aberration on the telephoto side. Furthermore, in the subsequent GR group, the on-axis marginal rays pass through at a lower ray height relative to the off-axis principal rays, thus minimizing the variation in on-axis chromatic aberration while the chromatic aberration correction effect increases at higher image heights.

[0289] In the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, the following conditions (1) and (2) are preferably satisfied.

[0290] (1) 2.50 < fT / fF1 < 11.00

[0291] (2) 0.15 < LiT / fT < 0.70

[0292] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0293] fF1: Focal length of the first front lens group GF1 at infinity.

[0294] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0295] Condition (1) specifies the ratio of the focal length of the entire system to the focal length of the first front lens group GF1 when looking at the far end at infinity. If the refractive power of the first front lens group GF1 is stronger, the light rays converge over a shorter distance, which helps to shorten the overall length of the optical system. If the overall length is the same, it leads to a reduction in the diameter of the optical system after the first front lens group GF1, thus also contributing to weight reduction. In addition, when the first front lens group GF1 includes a lens group, the first lens group G1 and the first front lens group GF1 become the same lens group.

[0296] If the upper limit of condition (1) is exceeded and the ratio of the focal length of the entire system to the focal length of the first front lens group GF1 when looking at the far end at infinity becomes larger, then the focal length of the first front lens group GF1 becomes shorter relative to the focal length of the entire system when looking at the far end at infinity, the refractive power becomes too strong, it is difficult to correct spherical aberration or coma, the optical performance decreases, and therefore it is not preferred.

[0297] If the lower limit of condition (1) is exceeded and the ratio of the focal length of the entire system to the focal length of the first front lens group GF1 when looking at the far end at infinity becomes smaller, then the focal length of the first front lens group GF1 becomes longer relative to the focal length of the entire system when looking at the far end at infinity, the refractive power becomes too weak, resulting in insufficient shortening of the total optical length, and therefore it is not preferred.

[0298] Furthermore, regarding conditional expression (1), it is preferable to set the lower limit value to 2.85 and the upper limit value to 10.00, more preferably to set the lower limit value to 3.15 and the upper limit value to 9.00, even more preferably to set the lower limit value to 3.23 and the upper limit value to 8.80, even more preferably to set the lower limit value to 3.27 and the upper limit value to 8.70, and even more preferably to set the lower limit value to 3.30 and the upper limit value to 8.50, thereby more reliably obtaining the aforementioned effects.

[0299] Condition (2) specifies the ratio (telephoto ratio) of the optical axis length (total optical length) from the object side to the image plane when viewing at infinity to the focal length of the entire system when viewing at infinity. It serves as an indicator of the degree to which the total optical length is shortened relative to the focal length of the optical system. Furthermore, the parallel plane plate positioned between the lens with refractive power on the image side and the image plane is not considered a lens. In calculating LiT, it is calculated using the air equivalent length if the parallel plane plate were replaced with air.

[0300] If the upper limit of condition (2) is exceeded and the ratio of the length of the optical axis from the side closest to the object to the image plane when viewing from infinity to the far end to the focal length of the entire system when viewing from infinity to the far end becomes larger, then the length of the optical axis from the side closest to the object to the image plane when viewing from infinity to the far end becomes too long relative to the focal length of the entire system when viewing from infinity to the far end, and the miniaturization is insufficient, so it is not preferred.

[0301] If the lower limit of condition (2) is exceeded and the ratio of the length of the optical axis from the side closest to the object to the image plane when looking at the far end at infinity to the focal length of the entire system when looking at the far end at infinity becomes smaller, then the length of the optical axis from the side closest to the object to the image plane when looking at the far end at infinity becomes too short relative to the focal length of the entire system when looking at the far end at infinity. Various aberrations such as spherical aberration or coma increase, and the performance of the optical system deteriorates. Therefore, it is not preferred.

[0302] In addition, regarding condition (2), it is preferable to set the lower limit value to 0.20 and the upper limit value to 0.60, more preferably to set the lower limit value to 0.22 and the upper limit value to 0.50, and even more preferably to set the lower limit value to 0.24 and the upper limit value to 0.48, thereby obtaining the aforementioned effect more reliably.

[0303] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, it is preferable to satisfy the following condition (3).

[0304] (3) 2.50 < fT / f1 < 11.00

[0305] fT: The focal length of the entire system when looking at the far end at infinity.

[0306] f1: Focal length of the first lens group G1

[0307] Condition (3) specifies the ratio of the focal length of the entire system at infinity to the focal length of the first lens group G1 at infinity. If the refractive power of the first lens group G1 is increased, the light rays converge over a shorter distance, which helps to shorten the overall length of the optical system. If the overall length is the same, it leads to a reduction in the diameter of the optical system after the first lens group G1, which also helps to reduce weight.

[0308] If the upper limit of condition (3) is exceeded and the ratio of the focal length of the entire system when looking at the far end at infinity to the focal length of the first lens group G1 when looking at the far end at infinity becomes larger, then the focal length of the first lens group G1 becomes shorter relative to the focal length of the entire system when looking at the far end at infinity, the refractive power becomes too strong, it is difficult to correct spherical aberration or coma, the optical performance decreases, and therefore it is not preferred.

[0309] If the lower limit of condition (3) is exceeded and the ratio of the focal length of the entire system when looking at the far end at infinity to the focal length of the first lens group G1 when looking at the far end at infinity becomes smaller, then the focal length of the first lens group G1 becomes longer relative to the focal length of the entire system when looking at the far end at infinity, the refractive power becomes too weak, and the reduction of the total optical length is insufficient, so it is not preferred.

[0310] Furthermore, regarding condition (3), it is preferable to set the lower limit value to 2.85 and the upper limit value to 10.00, more preferably to set the lower limit value to 3.15 and the upper limit value to 9.00, even more preferably to set the lower limit value to 3.23 and the upper limit value to 8.80, even more preferably to set the lower limit value to 3.27 and the upper limit value to 8.70, and even more preferably to set the lower limit value to 3.30 and the upper limit value to 8.50, thereby more reliably obtaining the aforementioned effects.

[0311] Furthermore, in the zoom imaging optical system involved in this invention, the following condition (4) is preferably satisfied.

[0312] (4) 1.2 < fT / fW < 7.0

[0313] fT: The focal length of the entire system when looking at the far end at infinity.

[0314] fW: Focal length of the entire system at infinity wide-angle end

[0315] Condition (4) specifies the ratio of the focal length of the entire system at the far end of the infinity telescope to the focal length of the entire system at the wide-angle end of the infinity telescope (magnification ratio).

[0316] If the upper limit of condition (4) is exceeded and the ratio of the focal length of the entire system at the far end of infinity to the focal length of the entire system at the wide-angle end of infinity becomes larger, then the aberration caused by magnification becomes too large, the optical performance decreases, and therefore it is not preferred.

[0317] If the lower limit of condition (4) is exceeded and the ratio of the focal length of the entire system at infinity to the focal length of the entire system at infinity wide-angle becomes smaller, then the change in field of view caused by magnification becomes smaller, and the usefulness of the zoom lens is impaired.

[0318] In addition, regarding condition (4), it is preferable to set the lower limit value to 1.5 and the upper limit value to 5.0, more preferably to set the lower limit value to 2.1 and the upper limit value to 4.7, and even more preferably to set the lower limit value to 2.4 and the upper limit value to 4.5, thereby more reliably obtaining the aforementioned effects.

[0319] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, it is preferable to satisfy the following condition (5).

[0320] (5) 60<LiT / (fT / fW)<250

[0321] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0322] fW: Focal length of the entire system at infinity wide-angle end

[0323] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0324] Condition (5) specifies the ratio of the length of the optical axis from the lens surface closest to the object to the image plane when viewing from infinity to the zoom ratio (the ratio of the focal length of the entire system at infinity to the focal length of the entire system at infinity wide-angle). Generally, increasing the zoom ratio tends to increase the size of the optical system, but this shows the extent to which the optical system can be miniaturized relative to the zoom ratio. Furthermore, the parallel plane plate positioned between the lens with refractive power closest to the image and the image plane is not considered a lens. In calculating LiT, the air equivalent length is used, replacing the parallel plane plate with air. The unit of the value calculated using this condition is mm.

[0325] If the upper limit of condition (5) is exceeded and the ratio of the length of the optical axis from the lens surface closest to the object to the image surface when looking at the far end at infinity to the zoom ratio becomes larger, then the length of the optical axis from the lens surface closest to the object to the image surface when looking at the far end at infinity becomes too long relative to the zoom ratio, making it difficult to miniaturize the optical system, and therefore it is not preferred.

[0326] If the lower limit of condition (5) is exceeded and the ratio of the length of the optical axis from the lens surface closest to the object to the image plane when looking at the far end at infinity to the magnification ratio becomes smaller, then the length of the optical axis from the lens surface closest to the object to the image plane when looking at the far end at infinity becomes too small, and various aberrations such as spherical aberration or coma aberration worsen, and the aberration variation caused by magnification also increases, so it is not preferred.

[0327] In addition, regarding condition (5), it is preferable to set the lower limit value to 80 and the upper limit value to 200, and more preferably to set the lower limit value to 85 and the upper limit value to 160, thereby obtaining the aforementioned effect more reliably.

[0328] Furthermore, in the zoom imaging optical system of the present invention, the first lens group G1, positioned closest to the object, is preferably fixed relative to the image plane when zooming from the wide-angle end to the telephoto end. In super telephoto zoom lenses as described in the present invention, the lens group positioned closest to the object has a large lens diameter and is also heavy. If this lens group moves during zooming, the center of gravity shifts significantly, altering the balance of the equipment during photography, which is therefore undesirable.

[0329] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, the first front lens group GF1 preferably satisfies the following condition (6).

[0330] (6) 1.5 < fF1 / ΦS1T < 5.0

[0331] fF1: Focal length of the first front lens group GF1 at infinity.

[0332] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[0333] Condition (6) specifies the ratio of the focal length of the first front lens group GF1 at infinity to the diameter of the ray on the upper edge of the surface closest to the object at infinity, which is equivalent to the apparent F-value of the first front lens group GF1 at infinity. If the ratio of the focal length of the first front lens group GF1 at infinity to the diameter of the ray on the upper edge of the surface closest to the object at infinity is small, it indicates that the light converges over a shorter distance, thus contributing to the miniaturization of the optical system.

[0334] If the upper limit of condition (6) is exceeded and the ratio of the focal length of the first front lens group GF1 at infinity to the diameter of the axial edge ray on the surface closest to the object at infinity increases, then the refractive power of the first front lens group GF1 decreases, the optical system becomes longer, and the light incident on the second front lens group GF2 will not converge sufficiently. Therefore, the lens diameter increases, making it difficult to achieve miniaturization and weight reduction, and thus it is not preferred.

[0335] If the lower limit of condition (6) is exceeded and the ratio of the focal length of the first front lens group GF1 at infinity to the diameter of the axial edge ray on the surface closest to the object at infinity becomes smaller, then the refractive power of the first front lens group GF1 becomes too strong, various aberrations such as spherical aberration or coma aberration worsen, and the optical performance deteriorates, so it is not preferred.

[0336] In addition, regarding condition (6), it is preferable to set the lower limit value to 1.6 and the upper limit value to 4.0, more preferably to set the lower limit value to 1.7 and the upper limit value to 3.3, and even more preferably to set the lower limit value to 1.8 and the upper limit value to 2.9, thereby obtaining the aforementioned effects more reliably.

[0337] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, the first front lens group GF1 preferably satisfies the following condition (7).

[0338] (7)0.40<ΦG1FrT / ΦS1T<0.87

[0339] ΦG1FrT: The diameter of the on-axis edge ray on the image-side plane of the first front lens group GF1 when viewing at infinity.

[0340] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[0341] Condition (7) specifies the ratio of the diameter of the axial edge ray on the surface closest to the image in the first front lens group GF1 when viewing from infinity to the diameter of the axial edge ray on the surface closest to the object when viewing from infinity, indicating the extent to which the height of the axial edge ray can be reduced when passing through the first front lens group GF1.

[0342] If the upper limit of condition (7) is exceeded and the ratio of the diameter of the on-axis edge ray on the surface closest to the image in the first front lens group GF1 when looking at the far end at infinity to the diameter of the diameter of the on-axis edge ray on the surface closest to the object in the far end at infinity increases, it indicates that the height of the on-axis edge ray in the first front lens group GF1 is not sufficiently reduced, and the lens diameter of the second front lens group GF2 increases, making it difficult to achieve miniaturization and weight reduction, and therefore it is not preferred.

[0343] If the lower limit of condition (7) is exceeded and the ratio of the diameter of the axial edge ray on the surface closest to the image side of the first front lens group GF1 when looking at the far end at infinity to the diameter of the axial edge ray on the surface closest to the object side when looking at the far end at infinity becomes smaller, then the refractive power of the first front lens group GF1 becomes too strong, and various aberrations such as spherical aberration or coma aberration worsen, resulting in a decrease in optical performance, and therefore it is not preferred.

[0344] In addition, regarding condition (7), it is preferable to set the lower limit value to 0.50 and the upper limit value to 0.85, more preferably to set the lower limit value to 0.55 and the upper limit value to 0.82, and even more preferably to set the lower limit value to 0.57 and the upper limit value to 0.80, thereby obtaining the aforementioned effect more reliably.

[0345] Furthermore, in the zoom imaging optical system involved in this invention, in order to ensure the zoom ratio and achieve high optical performance, the first front lens group GF1 preferably satisfies the following condition (8).

[0346] (8) 0.08 < LGF1 / LrT < 0.50

[0347] LGF1: The length of the optical axis of the first front lens group GF1 when viewing at infinity.

[0348] LrT: The length of the optical axis from the lens surface closest to the object to the lens surface closest to the image when viewed from infinity.

[0349] Condition (8) specifies the ratio of the length of the optical axis of the first front lens group GF1 when viewing from infinity to the length of the optical axis from the lens surface closest to the object to the lens surface closest to the image when viewing from infinity, indicating the proportion of the length of the lens portion of the optical system relative to the length of the first front lens group GF1 when viewing from infinity.

[0350] If the upper limit of condition (8) is exceeded and the ratio of the length of the optical axis of the first front lens group GF1 when looking at the far end at infinity to the length of the optical axis from the lens surface closest to the object side to the lens surface closest to the image side when looking at the far end at infinity increases, then the ratio of the length of the lens portion of the first front lens group GF1 to the length of the lens portion of the optical system when looking at the far end at infinity increases, which limits the amount of movement of the lens group that bears the magnification effect, which is located at a position closer to the image side than the first front lens group GF1. Therefore, it is not easy to increase the magnification ratio, so it is not preferred.

[0351] If the lower limit of condition (8) is exceeded and the ratio of the length of the optical axis of the first front lens group GF1 when looking at the far end at infinity to the length of the optical axis from the lens surface closest to the object to the lens surface closest to the image when looking at the far end at infinity becomes smaller, then the refractive power of the first front lens group GF1 becomes too strong, and various aberrations such as spherical aberration or coma aberration worsen, resulting in a decrease in optical performance, and therefore it is not preferred.

[0352] Furthermore, regarding conditional expression (8), it is preferable to set the lower limit value to 0.10 and the upper limit value to 0.30, more preferably to set the lower limit value to 0.11 and the upper limit value to 0.28, even more preferably to set the lower limit value to 0.12 and the upper limit value to 0.26, and even more preferably to set the lower limit value to 0.13 and the upper limit value to 0.25, thereby more reliably obtaining the aforementioned effects.

[0353] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, the first front lens group GF1 preferably satisfies the following condition (9).

[0354] (9)0.15<LairGF1 / LGF1<0.83

[0355] LairGF1: The largest air gap on the optical axis within the first front lens group GF1 when viewing at infinity.

[0356] LGF1: The length of the optical axis of the first front lens group GF1 when viewing at infinity.

[0357] Condition (9) specifies the ratio of the maximum air gap on the optical axis within the first front lens group GF1 at infinity to the length on the optical axis of the first front lens group GF1 at infinity. The first front lens group GF1 is divided into object-side lens units and image-side lens units, with the maximum air gap in the first front lens group GF1 at infinity as the boundary. If the air gap is increased, the lens diameter of the image-side lens units becomes smaller (here, "lens unit" refers to the lens group within the first front lens group GF1). Therefore, it helps to reduce the weight of the image-side lens units and contributes to the lightweighting of the first front lens group GF1. If the air gap accounts for a larger proportion of the length on the optical axis of the first front lens group GF1 at infinity, the lightweighting of the first front lens group GF1 is more effective.

[0358] If the upper limit of condition (9) is exceeded and the ratio of the largest air gap on the optical axis within the first front lens group GF1 at infinity to the length on the optical axis of the first front lens group GF1 at infinity increases, then the total length of the optical system increases and miniaturization becomes difficult (this holds true if the change from removing the portion of LairGF1 from LGF1 is much smaller than the change in LairGF1 itself. In short, if the thickness of the constructed lens remains constant, then increasing the air gap between them is the direction that increases the overall thickness of the lens group).

[0359] If the lower limit of condition (9) is exceeded and the ratio of the maximum air gap on the optical axis of the first front lens group GF1 when looking at the far end at infinity to the length on the optical axis of the first front lens group GF1 when looking at the far end at infinity becomes smaller, then the lens diameter of the image-side lens unit will not become smaller, so it is difficult to make the first front lens group GF1 lighter, and therefore it is not preferred.

[0360] In addition, regarding condition (9), it is preferable to set the lower limit value to 0.22 and the upper limit value to 0.70, and more preferably to set the lower limit value to 0.30 and the upper limit value to 0.60, thereby obtaining the aforementioned effect more reliably.

[0361] Furthermore, in the zoom imaging optical system of the present invention, the first front lens group GF1 preferably has a convex lens positioned closest to the object side and a concave lens positioned closest to the image side. The first front lens group GF1 has the function of suppressing chromatic aberration while converging light. Typically, to suppress chromatic aberration, a combination of a convex lens and a concave lens is required, and the placement of the concave lens is essential. If a concave lens is placed, it has the effect of diverging light, which inevitably leads to an increase in the diameter of the lens immediately placed on the image side. Therefore, by placing a convex lens at the position closest to the object side of the first front lens group GF1 and a concave lens at the position closest to the image side of the first front lens group GF1, the lens diameter of the first front lens group GF1 can be effectively suppressed.

[0362] Furthermore, in the zoom imaging optical system of the present invention, the first front lens group GF1 is preferably configured with a convex lens at the position closest to the object side, and satisfies the following condition (10).

[0363] (10)0.20<LairGF1 / LgGF1<3.50

[0364] LairGF1: The largest air gap on the optical axis within the first front lens group GF1 when viewing at infinity.

[0365] LgGF1: The total thickness along the optical axis of all lenses constituting the first front lens group GF1.

[0366] Condition (10) specifies the ratio of the maximum air gap on the optical axis within the first front lens group GF1 at infinity to the total thickness on the optical axis of all lenses constituting the first front lens group GF1. The first front lens group GF1 is divided into object-side lens units and image-side lens units, with the maximum air gap in the first front lens group GF1 at infinity as the boundary. If the air gap is increased, the lens diameter of the image-side lens units becomes smaller (here, "lens unit" refers to the lens group within the first front lens group GF1). Therefore, it helps to reduce the weight of the image-side lens units and contributes to the lightweighting of the first front lens group GF1.

[0367] If the upper limit of condition (10) is exceeded and the ratio of the maximum air gap on the optical axis in the first front lens group GF1 to the total thickness on the optical axis of all lenses constituting the first front lens group GF1 when looking at the far end indefinitely increases, the overall thickness on the optical axis of the first front lens group GF1 increases, making it difficult to achieve miniaturization of the optical system, and therefore not preferred.

[0368] If the lower limit of condition (10) is exceeded and the ratio of the maximum air gap on the optical axis in the first front lens group GF1 when looking at the far end at infinity to the total thickness on the optical axis of all lenses constituting the first front lens group GF1 becomes smaller, then the lens diameter of the image-side lens unit increases, resulting in an increase in the weight of the optical system, which is therefore not preferred.

[0369] Furthermore, regarding conditional expression (10), it is preferable to set the lower limit value to 0.50 and the upper limit value to 3.00, more preferably to set the lower limit value to 0.80 and the upper limit value to 2.80, even more preferably to set the lower limit value to 1.00 and the upper limit value to 2.70, and even more preferably to set the lower limit value to 1.03 and the upper limit value to 2.50, thereby more reliably obtaining the aforementioned effects.

[0370] Furthermore, in the zoom imaging optical system involved in this invention, in order to effectively correct the magnification chromatic aberration on the telescope side, the subsequent group GR preferably has one or more convex lenses that satisfy the following conditions (11) and (12).

[0371] (11)0.00<(-0.01176×vdpLgr-ndpLgr+2.2719) / (((-0.01176)^2+(2.2719)^2)^(1 / 2))

[0372] (12) ΔPgFpLgr<-0.0010

[0373] vdpLgr: The Abbe number of the convex lens possessed by the subsequent group GR.

[0374] ndpLgr: The refractive index of the convex lens possessed by the subsequent group GR.

[0375] ΔPgFpLgr: Anomalous dispersion of the convex lens possessed by the subsequent group GR

[0376] Condition (11) specifies the preferred Abbe number and refractive index of the convex lens in the subsequent group GR (when the horizontal axis is set to the Abbe number vd and the vertical axis to the refractive index nd, it represents the distance between the points nd and vd of the corresponding convex lens drawn by the straight lines passing through the points nd: 1.516798 vd: 64.2 and nd: 1.903658 vd: 31.31). The subsequent group GR plays the role of image plane compensation. If a high refractive index glass material is used in the concave lens and a low refractive index glass material is used in the convex lens, the Pesvalle of the entire system is reduced, which can ensure the flatness of the image plane.

[0377] If the lower limit of condition (11) is exceeded, then if the same Abbe number is considered, then the glass material with the upward direction of refractive index must be selected. The Petzval and the direction of aberration cannot be guaranteed to ensure the flatness of the image plane, so it is not preferred.

[0378] In addition, regarding condition (11), it is desirable to specify the lower limit value as 0.02, which would make the aforementioned effect more reliable.

[0379] Condition (12) specifies a preferred range for the anomalous dispersion of the convex lens in the subsequent group GR. In the subsequent group GR, by using a glass material with negative anomalous dispersion in the convex lens, the effect of correcting the g-line in the overdirection is produced, which can correct the magnification chromatic aberration on the telescope side.

[0380] If the upper limit of condition (12) is exceeded and the abnormal dispersion of the convex lens in the subsequent group GR increases, the effect of correcting the g line in the over-direction is insufficient, and it is difficult to correct the magnification chromatic aberration on the telescope side, so it is not preferred.

[0381] In addition, regarding condition (12), it is preferable to specify the upper limit value as -0.0020, more preferably as -0.0030, and even more preferably as -0.0040, thereby making the aforementioned effect more reliable.

[0382] Furthermore, in the zoom imaging optical system of the present invention, in order to effectively correct the magnification chromatic aberration on the telescope side, it is preferable to have one or more concave lenses that satisfy the following condition (13) at the image side position starting from lens Lb.

[0383] (13) ΔPgFnLbr>0.009

[0384] ΔPgFnLbr: Anomalous dispersion of a concave lens positioned on the image side, starting from lens Lb.

[0385] Lens Lb is defined as a lens that is positioned closer to the image side than the aperture stop S, and at infinity, the position of the lens surface on the object side where the off-axis principal ray is incident is higher than the position of the on-axis edge ray incident on that lens surface, and is positioned closest to the object side.

[0386] Condition (13) specifies a preferred range for the anomalous dispersion of at least one concave lens positioned further on the image side than lens Lb. The image-side lens from lens Lb becomes the lens at which the off-axis principal ray passes through a position higher than the on-axis edge ray when viewed from infinity. As can be seen from references 1 and 2, the lens further on the image side than Lb becomes more advantageous for correcting magnification chromatic aberration than correcting on-axis chromatic aberration. Therefore, by using a glass material with positive anomalous dispersion in the concave lens further on the image side than Lb, an effect of correcting the g-line in the overdirection is achieved, effectively correcting magnification chromatic aberration on the telescopic side.

[0387] If the lower limit of condition (13) is exceeded and the aberrant dispersion of the concave lens that is closer to the image side than Lb becomes smaller, then the effect of correcting the g line in the overdirection is insufficient, and it is difficult to correct the magnification chromatic aberration on the telescope side, so it is not preferred.

[0388] In addition, regarding condition (13), it is preferable to specify the lower limit value as 0.010, more preferably as 0.013, and even more preferably as 0.017, thereby making the aforementioned effect more reliable.

[0389] Furthermore, in the zoom imaging optical system of the present invention, it is preferable to have one or more concave lenses that satisfy the following condition (14) disposed at the image side position starting from lens Lb.

[0390] (14) vdnLbr×ΔPgFnLbr>0.8

[0391] vdnLbr: The Abbe number of a concave lens positioned on the image side, starting from lens Lb.

[0392] ΔPgFnLbr: Anomalous dispersion of a concave lens positioned on the image side, starting from lens Lb.

[0393] Condition (14) defines the preferred range by comparing the relationship between the Abbe number and anomalous dispersion of the concave lens that is closer to the image side than Lb. Using a glass material with positive anomalous dispersion in a concave lens that is closer to the image side than Lb produces the effect of correcting the g-line in the overdirection, thus correcting chromatic aberration on the telescope side. Furthermore, glass materials that satisfy condition (14) are mostly low-refractive-index, low-dispersion glass materials, making it easier to achieve both chromatic aberration correction and image plane compensation.

[0394] If the lower limit of condition (14) is exceeded and the aberrant dispersion of the concave lens that is closer to the image side than Lb becomes smaller, then the effect of correcting the g line in the overdirection is insufficient, and it is difficult to correct the magnification chromatic aberration on the telescope side, so it is not preferred.

[0395] In addition, regarding condition (14), it is preferable to specify the lower limit value as 0.9, and more preferably as 1.2, thereby making the aforementioned effect more reliable.

[0396] Furthermore, in the zoom imaging optical system of the present invention, the subsequent group GR preferably has one or more concave lenses that satisfy the following condition (15).

[0397] (15) vdnLgr×ΔPgFnLgr>0.8

[0398] vdnLgr: The Abbe number of the concave lens possessed by the subsequent group GR.

[0399] ΔPgFnLgr: Anomalous dispersion of the concave lens possessed by the subsequent group GR

[0400] Condition (15) specifies a preferred range for the relationship between the Abbe number and anomalous dispersion of the concave lens in the subsequent group GR. The subsequent group GR is the lens group located closest to the image side, and therefore it is necessarily a lens group that easily allows the off-axis principal ray to pass through at a position higher than the on-axis edge ray. Therefore, in order to effectively correct chromatic aberration at the telescope end, it is preferable to equip the subsequent group GR with a concave lens that satisfies condition (15).

[0401] If the lower limit of condition (15) is exceeded and the aberrant dispersion of the concave lens in the subsequent group GR decreases, the effect of correcting the g line in the overdirection is insufficient, and it is difficult to correct the magnification chromatic aberration on the telescope side, so it is not preferred.

[0402] In addition, regarding condition (15), it is preferable to specify the lower limit value as 0.9, and more preferably as 1.2, so that the aforementioned effect can be more reliable.

[0403] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization of the optical system, it is preferable to satisfy the following condition (16).

[0404] (16) 4.5 < fT / BFT < 130.0

[0405] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0406] BFT: The length of the optical axis from the lens surface closest to the image side to the image plane when looking at the farthest point at infinity.

[0407] Condition (16) specifies the ratio of the focal length of the entire system at infinity to the length of the optical axis from the lens surface closest to the image to the image plane at infinity. This indicates whether the back focal length can be shortened to reduce the optical system length, and whether miniaturization of the optical system can be achieved by satisfying condition (16). Furthermore, the parallel plane plate positioned between the lens with refractive power closest to the image and the image plane is not considered a lens. In calculating the BFT, the air equivalent length is used if the parallel plane plate is replaced with air.

[0408] If the upper limit of condition (16) is exceeded and the ratio of the focal length of the entire system when looking at the far end at infinity to the length of the optical axis from the lens surface closest to the image surface when looking at the far end at infinity becomes large, then the length of the optical axis from the lens surface closest to the image surface when looking at the far end at infinity becomes too small, causing inconvenience in connecting with the camera equipment, and therefore is not preferred.

[0409] If the lower limit of condition (16) is exceeded and the ratio of the focal length of the entire system when looking at the far end at infinity to the length of the optical axis from the lens surface closest to the image surface when looking at the far end at infinity becomes smaller, then the length of the optical axis from the lens surface closest to the image surface when looking at the far end at infinity becomes too large, the optical system increases in size, and therefore it is not preferred.

[0410] In addition, regarding condition (16), it is preferable to set the lower limit value to 6.5 and the upper limit value to 120.0, more preferably to set the lower limit value to 8.0 and the upper limit value to 110.0, and even more preferably to set the lower limit value to 10.0 and the upper limit value to 35.0, thereby obtaining the aforementioned effect more reliably.

[0411] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization of the optical system, it is preferable to satisfy the following condition (17).

[0412] (17) 4.0 < LiT / BFT < 35.0

[0413] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0414] BFT: The length of the optical axis from the lens surface closest to the image side to the image plane when looking at the farthest point at infinity.

[0415] Condition (17) specifies the ratio of the length (total optical length) of the optical axis from the lens surface closest to the object to the image plane when looking at the far end at infinity to the length of the optical axis from the lens surface closest to the image to the image plane. This indicates whether the back focal length can be shortened to shorten the optical system, and whether the optical system can be miniaturized by satisfying condition (17). In addition, the parallel plane plate placed between the lens with refractive power closest to the image and the image plane is not counted as a lens. When calculating LiT and BFT, the air equivalent length is calculated by replacing the parallel plane plate with air.

[0416] If the upper limit of condition (17) is exceeded and the ratio of the length of the optical axis from the lens surface closest to the object to the image surface when looking at the far end at infinity increases, then LiT increases, making it difficult to achieve miniaturization of the optical system, and therefore it is not preferred.

[0417] If the lower limit of condition (17) is exceeded and the ratio of the length of the optical axis from the lens surface closest to the object to the image surface when looking at the far end at infinity becomes smaller, then LiT needs to be reduced. It is difficult to correct various aberrations such as spherical aberration or image curvature while maintaining the magnification ratio, so it is not preferred.

[0418] In addition, regarding condition (17), it is preferable to set the lower limit value to 4.5 and the upper limit value to 30.0, and more preferably to set the lower limit value to 5.0 and the upper limit value to 27.0, thereby obtaining the aforementioned effect more reliably.

[0419] Furthermore, in the zoom imaging optical system of the present invention, all convex lenses constituting the first front lens group GF1 preferably satisfy the following condition (18).

[0420] (18) ΔPgFpGF1>0.000

[0421] ΔPgFpGF1: The anomalous dispersion of the convex lens possessed by the front lens group GF1.

[0422] Condition (18) specifies the anomalous dispersion that all convex lenses constituting the first front lens group GF1 must satisfy. In the telephoto super telephoto zoom lens of the present invention, by using a glass material with positive anomalous dispersion in the convex lens on the object side, on-axis chromatic aberration and magnification chromatic aberration on the telephoto side can be effectively corrected.

[0423] If the lower limit of condition (18) is exceeded and the abnormal dispersion that all convex lenses constituting the first front lens group GF1 should satisfy becomes smaller, then the correction of on-axis chromatic aberration and magnification chromatic aberration on the telescope side is insufficient, and therefore it is not preferred.

[0424] In addition, regarding condition (18), it is preferable to set the lower limit value to 0.002, more preferably to 0.005, and even more preferably to 0.007, thereby more reliably obtaining the aforementioned effect.

[0425] Furthermore, in the zoom imaging optical system of the present invention, all convex lenses constituting the first front lens group GF1 preferably satisfy the following condition (19).

[0426] (19) ndpGF1 < 1.68

[0427] ndpGF1: The refractive index of the convex lens possessed by the front lens group GF1.

[0428] Condition (19) specifies the refractive index that all convex lenses constituting the first front lens group GF1 should satisfy. Generally, the higher the refractive index of the glass material, the smaller the Abbe number and the higher the dispersion. If such a glass material is used in the convex lens on the object side, it is difficult to correct the on-axis chromatic aberration and magnification chromatic aberration on the telescope side, so it is not preferred.

[0429] If the upper limit of condition (19) is exceeded and the refractive index of all convex lenses constituting the first front lens group GF1 becomes higher, then the correction of on-axis chromatic aberration and magnification chromatic aberration on the telescope side is insufficient, and therefore it is not preferred.

[0430] In addition, regarding condition (19), the upper limit value is set to 1.65, more preferably 1.63, and even more preferably 1.60, thereby more reliably obtaining the aforementioned effect.

[0431] Furthermore, in the zoom imaging optical system involved in this invention, the following condition (20) is preferably satisfied.

[0432] (20) -75.0 < fT / fF2 < -5.0

[0433] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0434] fF2: Focal length of the second front lens group GF2 at infinity.

[0435] Condition (20) specifies the ratio of the focal length of the entire system to the focal length of the second front lens group GF2 when looking at the far end at infinity. The second front lens group GF2 is the group that bears the main zoom effect. By properly setting the refractive power of the second front lens group GF2, it is helpful to ensure the zoom ratio and the miniaturization of the optical system.

[0436] If the upper limit of conditional expression (20) is exceeded and the ratio of the focal length of the entire system to the focal length of the second front lens group GF2 when looking at the far end at infinity becomes larger, the negative refractive power of the second front lens group GF2 weakens, the amount of movement of the second front lens group GF2 used for magnification increases, and the total length of the optical system increases, which is not preferable. Furthermore, if it is desired to increase the magnification effect of a lens group positioned further on the image side than the second front lens group GF2, the total length of the optical system increases or the number of lenses increases, which is also not preferable.

[0437] If the lower limit of condition (20) is exceeded and the ratio of the focal length of the entire system to the focal length of the second front lens group GF2 when looking at the far end at infinity becomes smaller, then the negative refractive power of the second front lens group GF2 becomes too strong, resulting in various aberrations such as image plane curvature, and therefore it is not preferred.

[0438] In addition, regarding the condition (20), it is preferable to set the lower limit value to -60.0 and the upper limit value to -6.0, more preferably to set the lower limit value to -45.0 and the upper limit value to -7.0, and even more preferably to set the lower limit value to -30.0 and the upper limit value to -10.9, thereby obtaining the aforementioned effect more reliably.

[0439] Furthermore, in the zoom imaging optical system involved in this invention, the following condition (21) is preferably satisfied.

[0440] (21) -7.0 < fF1 / fF2 < -2.0

[0441] fF1: Focal length of the first front lens group GF1 at infinity.

[0442] fF2: Focal length of the second front lens group GF2 at infinity.

[0443] Condition (21) specifies the ratio of the focal lengths of the first front lens group GF1 to the second front lens group GF2 when viewing at infinity. By setting (21) appropriately, it is helpful to ensure the zoom ratio and the miniaturization of the optical system.

[0444] If the upper limit of condition (21) is exceeded and the ratio of the focal length of the first front lens group GF1 to the second front lens group GF2 when looking at the far end at infinity becomes larger, then the refractive power of the second front lens group GF1 becomes too strong, resulting in a deterioration of spherical aberration or image plane curvature, and therefore is not preferred.

[0445] If the lower limit of condition (21) is exceeded and the ratio of the focal length of the first front lens group GF1 to the second front lens group GF2 at infinity telephoto becomes smaller, then the refractive power of the first front lens group GF1 is insufficient relative to the focal length at the telephoto end, and the total length of the optical system becomes longer, which is therefore not preferred.

[0446] In addition, regarding condition (21), it is preferable to set the lower limit value to -6.0 and the upper limit value to -2.5, and more preferably to set the lower limit value to -5.5 and the upper limit value to -3.0, thereby obtaining the aforementioned effect more reliably.

[0447] Furthermore, in the zoom imaging optical system involved in this invention, in order to achieve miniaturization and weight reduction of the optical system, the first front lens group GF1 and the second front lens group GF2 preferably satisfy the following condition (22).

[0448] (22)0.20<ΦG2FfT / ΦS1T<0.60

[0449] ΦG2FfT: The diameter of the on-axis edge ray on the surface closest to the object in the second front lens group GF2 when viewing at infinity.

[0450] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[0451] Condition (22) specifies the ratio of the diameter of the axial edge ray on the surface closest to the object in the second front lens group GF2 when looking at the far end at infinity to the diameter of the axial edge ray on the surface closest to the object in the first front lens group GF1 when looking at the far end at infinity. Therefore, it indicates whether the height of the axial edge ray incident on the second front lens group GF2 can be reduced in the first front lens group GF1 to what extent.

[0452] If the upper limit of condition (22) is exceeded and the ratio of the diameter of the on-axis edge ray on the surface closest to the object in the second front lens group GF2 when looking at the far end at infinity to the diameter of the on-axis edge ray on the surface closest to the object in the first front lens group GF1 when looking at the far end at infinity increases, it indicates that the height of the on-axis edge ray in the first front lens group GF1 has not been sufficiently reduced, and the lens diameter of the second front lens group GF2 has increased, making it difficult to achieve miniaturization and weight reduction, and therefore it is not preferred.

[0453] If the lower limit of condition (22) is exceeded and the ratio of the diameter of the axial edge ray on the surface closest to the object in the second front lens group GF2 when looking at the far end at infinity to the diameter of the axial edge ray on the surface closest to the object in the first front lens group GF1 when looking at the far end at infinity becomes smaller, then the refractive power of the first front lens group GF1 becomes too strong, resulting in various aberrations such as spherical aberration or coma, and a decrease in optical performance, so it is not preferred.

[0454] In addition, regarding condition (22), it is preferable to set the lower limit value to 0.25 and the upper limit value to 0.55, more preferably to set the lower limit value to 0.30 and the upper limit value to 0.51, and even more preferably to set the lower limit value to 0.33 and the upper limit value to 0.45, thereby obtaining the aforementioned effect more reliably.

[0455] Furthermore, in the zoom imaging optical system of the present invention, when the first front lens group GF1 comprises two lens groups, the image-side lens group preferably moves toward the object side when zooming from the wide-angle end to the telephoto end.

[0456] When zooming from the wide-angle end to the telephoto end, if the image-side lens group in the first front lens group GF1 moves towards the image side, it means that the focal length of the first front lens group GF1 becomes smaller on the telephoto side. Since it acts in the direction that cancels the zoom effect after the second front lens group GF2, it has a disadvantage in ensuring the zoom ratio, and is therefore not preferred.

[0457] Furthermore, in the zoom imaging optical system of the present invention, when the first front lens group GF1 is composed of two lens groups, the distance between the image-side lens group and the first lens group G1 disposed on the object side is preferably reduced when zooming from the wide-angle end to the telephoto end, and the distance between the image-side lens group and the second front lens group GF2 disposed on the image side is increased.

[0458] When zooming from the wide-angle end to the telephoto end, if the distance between the first lens group G1 located on the object side increases and the distance between the second front lens group GF2 located on the image side decreases, it means that the focal length of the first front lens group GF1 becomes smaller on the telephoto side, and it acts in the direction that cancels the zoom effect after the second front lens group GF2. Therefore, it has a disadvantage in ensuring the zoom ratio and is not preferred.

[0459] Furthermore, in the zoom imaging optical system of the present invention, the focusing lens group is preferably a lens group with a small lens diameter, which has the advantage of enabling miniaturization of the actuator. Therefore, at least one lens group constituting the intermediate group GM is preferably moved along the optical axis when focusing from an object at infinity to a nearby object.

[0460] Furthermore, in the zoom imaging optical system of the present invention, diffractive optical elements are preferably not used. While diffractive optical elements can provide chromatic aberration correction or aspherical effects on the diffraction surface, they can lead to unwanted diffraction light caused by shape or halos or ghosting caused by light rays outside the field of view, and are therefore not preferred.

[0461] Furthermore, in the zoom imaging optical system involved in this invention, the second front lens group GF2, which has negative refractive power as a whole, undertakes the main zoom effect, and all lens groups constituting the second front lens group GF2 preferably move towards the image side when zooming from the wide-angle end to the telephoto end.

[0462] Furthermore, in the zoom imaging optical system involved in this invention, in order to prevent the mechanical mechanism from becoming complicated, the subsequent GR is preferably fixed relative to the image plane when zooming from the wide-angle end to the telephoto end.

[0463] Next, the lens structure of an embodiment of the imaging optical system of the present invention will be described. Furthermore, in the following description, the lens structure will be described in order from the object side to the image side.

[0464] In the [Surface Data], the surface number is the number of the lens surface or aperture stop S measured from the object side; r is the radius of curvature of each lens surface; d is the interval between each lens surface; nd is the refractive index relative to the d-line (wavelength 587.56 nm); vd is the Abbe number relative to the d-line; and ΔPgF is a value calculated using the formula PgF - 0.64833 + 0.00180 × vd. Furthermore, the corresponding glass materials, as examples of glasses corresponding to the refractive index, Abbe number, and ΔPgF recorded in the [Surface Data], include the glass material names of HOYACorporation, OHARA Inc., and HIKARI GLASS Co., Ltd.

[0465] Attached to the face number (The asterisk) indicates the distance from the lens surface to the aspherical surface. Furthermore, BF indicates the back focal length, and the distance to the object surface indicates the distance from the subject to the first surface of the lens.

[0466] The (aperture stop) attached to the surface number indicates that the aperture stop S is located at that position. ∞ (infinity) is marked on the radius of curvature relative to the plane or the aperture stop S.

[0467] In [Astrospherical Data], it shows how to assign the attached [Surface Data] to [Surface Data]. The values ​​of the coefficients for the aspherical shape of the lens surface. The aspherical shape is represented by the following formula. In the following formula, y represents the displacement from the optical axis in the direction orthogonal to the optical axis, z represents the displacement (vertical measure) from the intersection of the optical axis and the aspherical surface in the direction of the optical axis, r represents the radius of curvature of the reference sphere, and K represents the conic coefficient. Furthermore, the aspherical coefficients of the 4th, 6th, 8th, 10th, and 12th orders are represented by A4, A6, A8, A10, and A12, respectively.

[0468]

[0469] The [Various Data] section shows the focal length values ​​at various shooting distances under different focusing conditions.

[0470] The [Variable Interval Data] section shows the variable interval and BF value for various shooting distances and focus conditions.

[0471] The [Lens Group Data] section shows the object-side surface number that makes up each lens group and the combined focal length of the entire group.

[0472] Furthermore, in the aberration diagrams corresponding to each embodiment, d, g, and C represent the d-line, g-line, and C-line, respectively, and ΔS and ΔM represent the sagittal image plane and the meridional image plane, respectively.

[0473] In addition, in all the following specifications, unless otherwise stated, the focal length f, radius of curvature r, lens surface spacing d, and other lengths are in millimeters (mm), but the same optical performance can be obtained even in proportional magnification and proportional reduction in optical systems, and therefore are not limited thereto.

[0474] Furthermore, as lens names, the lens positioned closest to the object is called L1, the second lens positioned facing the image is called L2, and the third lens is called L3.

[0475] Furthermore, in the lens structure diagrams of each embodiment, the arrows indicate the trajectory of the lens group when zooming from the wide-angle end to the telephoto end, S represents the aperture stop, I represents the image plane, F represents the filter, and the single-dot dashed line passing through the center is the optical axis.

[0476] Next, the lens structure of an embodiment of the zoom imaging optical system of the present invention will be described.

[0477] Furthermore, in the following description, the lens structure is described in order from the object side to the image side.

[0478] [Example 1]

[0479] Figure 1 This is a diagram of the lens structure of the zoom imaging optical system described in Example 1 when focusing at infinity at the wide-angle end.

[0480] Figure 1 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power. The second front lens group GF2 includes a second lens group G2 with negative refractive power and a third lens group G3 with negative refractive power, and the whole has negative refractive power. The intermediate group GM includes a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power. The subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0481] Lens group G1 consists of a biconvex lens arranged sequentially from the object side, a convex meniscus lens with its convex surface facing the object side, and a combined lens of a biconvex lens and a biconcave lens. Lens group G2 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G3 consists of a combined lens of a convex meniscus lens with its convex surface facing the image side and a concave meniscus lens with its convex surface facing the image side. Lens group G4 consists of a convex meniscus lens with its convex surface facing the object side, a concave meniscus lens with its convex surface facing the object side, a biconvex lens, a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens of a convex meniscus lens with its convex surface facing the image side and a biconcave lens. Lens group G6 consists of a biconcave lens, a convex meniscus lens with its convex surface facing the image side, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 consists of a biconvex lens, a combined lens of a convex meniscus lens L20 with its convex surface facing the image side and a biconcave lens L21, a biconvex lens, a combined lens of a biconvex lens and a biconcave lens L24, a combined lens of a biconcave lens L25 and a biconvex lens L26, and a combined lens of a biconcave lens and a biconvex lens. Furthermore, it can function as a vibration damping group by moving L20 and L21 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L20 and L21 can also be used as vibration damping groups.

[0482] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 and the third lens group G3 move towards the image side, and the fourth lens group G4 to the sixth lens group G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 decreases, the interval between the fourth lens group G4 and the fifth lens group G5 increases and then decreases, and the interval becomes smaller at the telephoto end relative to the wide-angle end. The interval between the fifth lens group G5 and the sixth lens group G6 increases, the interval between the sixth lens group G6 and the seventh lens group G7 increases and then decreases, and the interval becomes larger at the telephoto end relative to the wide-angle end. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves along the optical axis towards the image side.

[0483] Lenses on the image side starting from L20 of the 7th lens group G7 become lenses where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 1, Lb becomes L20.

[0484] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0485] L25 becomes a lens that satisfies condition (13).

[0486] L25 becomes a lens that satisfies condition (14).

[0487] L25 becomes a lens that satisfies condition (15).

[0488] The following shows the specifications of the zoom imaging optical system involved in Example 1.

[0489] Numerical Example 1

[0490] Unit: mm

[0491] [Surface Data]

[0492]

[0493]

[0494]

[0495] [Various data]

[0496]

[0497] [Variable Interval Data]

[0498]

[0499]

[0500] [Lens Group Data]

[0501]

[0502] [Example 2]

[0503] Figure 14 This is a diagram of the lens structure of the zoom imaging optical system described in Example 2 when focusing at infinity at the wide-angle end.

[0504] Figure 14 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0505] Lens group G1 consists of a biconvex lens arranged sequentially from the object side, a convex meniscus lens with its convex surface facing the object side, and a combined lens of a biconvex lens and a biconcave lens. Lens group G2 consists of a biconcave lens, a combined lens of a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a convex meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a combined lens of a biconvex lens and a biconcave lens, and an aperture stop S. Lens group G5 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G6 consists of a combined lens of a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a combined lens consisting of a convex meniscus lens L18 (convex surface facing the object side), a biconvex lens L19, and a biconcave lens L20; a concave meniscus lens L21 (convex surface facing the object side), a biconvex lens, a biconcave lens, and a biconvex lens L24; a combined lens consisting of a biconcave lens L25 and a biconvex lens L26; and a combined lens consisting of a biconcave lens and a biconvex lens. Furthermore, it is possible to make L19 to L21 in the seventh lens group G7 function as a vibration damping group by moving them integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L19 to L21 can also be used as a vibration damping group.

[0506] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases and then decreases, and the interval becomes slightly smaller at the telephoto end relative to the wide-angle end. The interval between the fourth lens group G4 and the fifth lens group G5 decreases, the interval between the fifth lens group G5 and the sixth lens group G6 increases, and the interval between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves along the optical axis towards the image side.

[0507] Starting from L18 of the 7th lens group G7, the image-side lenses are those where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system described in Embodiment 2, Lb becomes L18.

[0508] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0509] L21 and L25 become lenses that satisfy condition (13).

[0510] L25 becomes a lens that satisfies condition (14).

[0511] L25 becomes a lens that satisfies condition (15).

[0512] The following shows the specifications of the zoom imaging optical system involved in Example 2.

[0513] Numerical Example 2

[0514] Unit: mm

[0515] [Surface Data]

[0516]

[0517]

[0518] [Various data]

[0519]

[0520] [Variable Interval Data]

[0521]

[0522]

[0523] [Lens Group Data]

[0524]

[0525] [Example 3]

[0526] Figure 27 This is a diagram of the lens structure of the zoom imaging optical system described in Example 3 when focusing at infinity at the wide-angle end.

[0527] Figure 27 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power and a second lens group G2 with negative refractive power, and has positive refractive power overall. The second front lens group GF2 includes a third lens group G3 with negative refractive power. The intermediate group GM includes a fourth lens group G4 with positive refractive power and a fifth lens group G5 with negative refractive power. The subsequent group GR includes a sixth lens group G6 with negative refractive power.

[0528] Lens group G1 consists of a convex meniscus lens with its convex surface facing the object side and a biconvex lens, arranged sequentially from the object side. Lens group G2 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G3 consists of a combined lens of a convex meniscus lens with its convex surface facing the image side and a biconcave lens, and a combined lens of a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G4 consists of a convex meniscus lens with its convex surface facing the object side, a combined lens of a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, an aperture stop S, a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side, a combined lens of a convex meniscus lens L15 with its convex surface facing the image side and a biconcave lens L16, and a biconvex lens. Furthermore, the fourth lens group G4 can also function as a vibration damping group by moving L15 and L16 together in a substantially perpendicular direction relative to the optical axis, but lenses other than L15 and L16 can also be used as vibration damping groups. The fifth lens group G5 consists of biconvex and biconcave lenses. The sixth lens group G6 consists of a combined lens of a biconcave lens L20 and a biconvex lens, a combined lens of a biconcave lens L22 and a biconvex lens L23, and a combined lens of a biconcave and a biconvex lens.

[0529] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the sixth lens group G6 are fixed relative to the image plane. The second lens group G2 moves towards the object side, the third lens group G3 moves towards the image side, and the fourth lens group G4 and the fifth lens group G5 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 decreases, the interval between the second lens group G2 and the third lens group G3 increases, the interval between the third lens group G3 and the fourth lens group G4 decreases, the interval between the fourth lens group G4 and the fifth lens group G5 decreases, and the interval between the fifth lens group G5 and the sixth lens group G6 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves along the optical axis towards the image side.

[0530] The image-side lenses starting from L20 of the sixth lens group G6 become lenses where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system described in Embodiment 3, Lb becomes L20.

[0531] L23 becomes a lens that satisfies conditions (11) and (12).

[0532] L22 becomes a lens that satisfies condition (13).

[0533] L22 becomes a lens that satisfies condition (14).

[0534] L22 becomes a lens that satisfies condition (15).

[0535] The following shows the specifications of the zoom imaging optical system involved in Example 3.

[0536] Numerical Example 3

[0537] Unit: mm

[0538] [Surface Data]

[0539]

[0540]

[0541]

[0542] [Various data]

[0543]

[0544] [Variable Interval Data]

[0545]

[0546]

[0547] [Lens Group Data]

[0548]

[0549] [Example 4]

[0550] Figure 40 This is a diagram of the lens structure of the zoom imaging optical system described in Example 4 when focusing at infinity at the wide-angle end.

[0551] Figure 40 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0552] Lens group G1 consists of a biconvex lens arranged sequentially from the object side, a convex meniscus lens with its convex surface facing the object side, and a combined lens of a biconvex lens and a biconcave lens. Lens group G2 consists of a concave meniscus lens with its convex surface facing the object side, a combined lens of a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a combined lens of a biconvex lens and a biconcave lens, and an aperture stop S. Lens group G5 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G6 consists of a combined lens of a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a biconvex lens, a combined lens of a biconvex lens L19 and a biconcave lens L20, a biconcave lens L21, a biconvex lens L22, a combined lens of a biconcave lens and a biconvex lens L24, a combined lens of a biconcave lens L25 and a biconvex lens L26, a combined lens of a biconcave lens and a biconvex lens, a combined lens of a concave meniscus lens with its convex surface facing the object side and a biconvex lens and a concave meniscus lens with its convex surface facing the image side, a combined lens of a biconcave lens and a convex meniscus lens with its convex surface facing the object side, a combined lens of a biconvex lens and a biconcave lens, and a convex meniscus lens L36 with its convex surface facing the image side. Furthermore, it is possible to make L19 to L21 in the seventh lens group G7 function as a vibration damping group by moving them integrally in a substantially perpendicular direction relative to the optical axis, but it is also possible to use lenses other than L19 to L21 as a vibration damping group.

[0553] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases and then decreases, and the interval becomes slightly smaller at the telephoto end relative to the wide-angle end. The interval between the fourth lens group G4 and the fifth lens group G5 decreases, the interval between the fifth lens group G5 and the sixth lens group G6 increases, and the interval between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves along the optical axis towards the image side.

[0554] The image-side lenses starting from L22 of the 7th lens group G7 are lenses in which, at infinity, the position where the off-axis principal ray enters the lens surface on the object side is higher than the position where the on-axis edge ray enters the lens surface. Therefore, in the zoom imaging optical system described in Embodiment 4, Lb becomes L22.

[0555] L24, L26 and L36 are lenses that satisfy conditions (11) and (12).

[0556] L25 becomes a lens that satisfies condition (13).

[0557] L25 becomes a lens that satisfies condition (14).

[0558] L25 becomes a lens that satisfies condition (15).

[0559] The following shows the specifications of the zoom imaging optical system involved in Example 4.

[0560] Numerical Example 4

[0561] Unit: mm

[0562] [Surface Data]

[0563]

[0564]

[0565]

[0566] [Various data]

[0567]

[0568] [Variable Interval Data]

[0569]

[0570]

[0571] [Lens Group Data]

[0572]

[0573] [Example 5]

[0574] Figure 53 This is a diagram of the lens structure of the zoom imaging optical system described in Example 5 when focusing at infinity at the wide-angle end.

[0575] Figure 53The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power and a second lens group G2 with negative refractive power, and the whole has positive refractive power. The second front lens group GF2 includes a third lens group G3 with negative refractive power. The intermediate group GM includes a fourth lens group G4 with positive refractive power, a fifth lens group G5 with positive refractive power, a sixth lens group G6 with negative refractive power, and a seventh lens group G7 with positive refractive power. The subsequent group GR includes an eighth lens group G8 with negative refractive power.

[0576] The first lens group G1 consists of a biconvex lens arranged sequentially from the object side and a convex meniscus lens with its convex surface facing the object side. The second lens group G2 consists of a combined lens of a biconvex lens and a biconcave lens. The third lens group G3 consists of a combined lens of a convex meniscus lens with its convex surface facing the object side, a biconcave lens, and a convex meniscus lens with its convex surface facing the object side, a concave meniscus lens L8 with its convex surface facing the object side, a biconcave lens L9, and a biconvex lens L10. Furthermore, the third lens group G3 can function as a vibration damping group by moving L8 to L10 integrally relative to the optical axis in a substantially perpendicular direction; however, lenses other than L8 to L10 can also be used as vibration damping groups. Lens group G4 consists of a combined lens of a concave meniscus lens with its convex surface facing the object side and a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a combined lens of a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, an aperture stop S, and a combined lens of a biconvex lens and a biconcave lens. Lens group G5 consists of a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side. Lens group G6 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G7 consists of a combined lens of a biconvex lens L22 and a concave meniscus lens L23 with its convex surface facing the image side, and a combined lens of a biconcave lens L24 and a convex meniscus lens with its convex surface facing the object side. Lens group G8 consists of a combined lens of a biconvex lens L26 and a biconcave lens, and a combined lens of a biconvex lens and a concave meniscus lens L29 with its convex surface facing the image side.

[0577] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the eighth lens group G8 are fixed relative to the image plane. The second lens group G2 moves towards the object side, the third lens group G3 moves towards the image side, and the fourth to seventh lens groups G4 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 decreases, the interval between the second lens group G2 and the third lens group G3 increases, the interval between the third lens group G3 and the fourth lens group G4 decreases, the interval between the fourth lens group G4 and the fifth lens group G5 decreases, and the interval between the fifth lens group G5 and the sixth lens group G6 decreases and then increases. The interval becomes smaller relative to the wide-angle end at the telephoto end. The interval between the sixth lens group G6 and the seventh lens group G7 increases, and the interval between the seventh lens group G7 and the eighth lens group G8 increases. When focusing from an object at infinity to a closer object, the sixth lens group G6 moves along the optical axis towards the image side.

[0578] The image-side lenses starting from L22 of the 7th lens group G7 are lenses in which, at infinity, the position where the off-axis principal ray enters the lens surface on the object side is higher than the position where the on-axis edge ray enters the lens surface. Therefore, in the zoom imaging optical system according to Embodiment 5, Lb becomes L22.

[0579] L26 becomes a lens that satisfies conditions (11) and (12).

[0580] L23, L24 and L29 are lenses that satisfy condition (13).

[0581] L24 and L29 become lenses that satisfy condition (14).

[0582] L29 becomes a lens that satisfies condition (15).

[0583] The following shows the specifications of the zoom imaging optical system involved in Example 5.

[0584] Numerical Example 5

[0585] Unit: mm

[0586] [Surface Data]

[0587]

[0588]

[0589]

[0590] [Various data]

[0591]

[0592] [Variable Interval Data]

[0593]

[0594]

[0595] [Lens Group Data]

[0596]

[0597] [Example 6]

[0598] Figure 66 This is a diagram of the lens structure of the zoom imaging optical system described in Example 6 when focusing at infinity at the wide-angle end.

[0599] Figure 66 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with negative refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0600] Lens group G1 consists of a biconvex lens arranged sequentially from the object side, a convex meniscus lens with its convex surface facing the object side, and a combined lens of a biconvex lens and a biconcave lens. Lens group G2 consists of a biconcave lens, a combined lens of a biconcave lens and a biconvex lens. Lens group G3 consists of a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens of a biconvex lens and a biconcave lens. Lens group G6 consists of a concave meniscus lens with its convex surface facing the object side, a biconvex lens, and a combined lens of a convex meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a combined lens of biconvex lens L18, biconvex lens L19 and biconcave lens L20, a biconcave lens L21, a biconvex lens, a combined lens of biconcave lens and biconvex lens L24, a combined lens of biconcave lens L25 and biconvex lens L26, and a combined lens of biconcave lens and biconvex lens. Furthermore, it can function as a vibration damping group by moving L19 to L21 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L19 to L21 can also be used as vibration damping groups.

[0601] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases and then decreases, and the interval becomes slightly smaller at the telephoto end relative to the wide-angle end. The interval between the fourth lens group G4 and the fifth lens group G5 decreases, the interval between the fifth lens group G5 and the sixth lens group G6 increases, and the interval between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves along the optical axis towards the image side.

[0602] Starting from L18 of the 7th lens group G7, the image-side lenses are those where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system described in Embodiment 6, Lb becomes L18.

[0603] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0604] L21 and L25 become lenses that satisfy condition (13).

[0605] L21 and L25 become lenses that satisfy condition (14).

[0606] L21 and L25 become lenses that satisfy condition (15).

[0607] Numerical Example 6

[0608] Unit: mm

[0609] [Surface Data]

[0610]

[0611]

[0612]

[0613] [Various data]

[0614]

[0615] [Variable Interval Data]

[0616]

[0617]

[0618] [Lens Group Data]

[0619]

[0620] [Example 7]

[0621] Figure 79 This is a diagram of the lens structure of the zoom imaging optical system described in Example 7 when focusing at infinity at the wide-angle end.

[0622] Figure 79 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power. The second front lens group GF2 includes a second lens group G2 with positive refractive power and a third lens group G3 with negative refractive power, and the whole has negative refractive power. The intermediate group GM includes a fourth lens group G4 with positive refractive power. The subsequent group GR includes a fifth lens group G5 with negative refractive power.

[0623] Lens group G1 consists of a biconvex lens arranged sequentially from the object side, a convex meniscus lens with its convex surface facing the object side, and a combined lens of the biconvex and biconcave lenses. Lens group G2 consists of a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side. Lens group G3 consists of a biconcave lens, a biconcave lens, and a combined lens of a convex meniscus lens with its convex surface facing the object side. Lens group G4 consists of a convex meniscus lens with its convex surface facing the object side, a biconvex lens, a biconvex lens, a concave meniscus lens with its convex surface facing the image side, an aperture stop S, and a combined lens of the biconvex and biconcave lenses. The fifth lens group G5 consists of a combined lens of a concave meniscus lens with its convex surface facing the object side and a convex meniscus lens with its convex surface facing the object side, a combined lens of a convex meniscus lens L18 with its convex surface facing the object side, a combined lens of a biconvex lens L19 and a biconcave lens L20, a biconcave lens L21, a biconvex lens, a combined lens of a biconcave lens and a biconvex lens L24, a combined lens of a biconcave lens L25 and a biconvex lens L26, and a combined lens of a biconcave lens and a biconvex lens. Furthermore, it is possible to make L19 to L21 in the fifth lens group G5 function as a vibration damping group by moving them integrally relative to the optical axis in a substantially perpendicular direction, but it is also possible to use lenses other than L19 to L21 as a vibration damping group.

[0624] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed relative to the image plane, the second lens group G2 and the third lens group G3 move towards the image side along different trajectories, the fourth lens group G4 moves towards the object side, the interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 increases and then decreases, the interval becomes smaller relative to the wide-angle end at the telephoto end, the interval between the third lens group G3 and the fourth lens group G4 decreases, the interval between the fourth lens group G4 and the fifth lens group G5 increases, and when focusing from an object at infinity to a closer object, the second lens group G2 moves towards the object side.

[0625] Starting from L18 of the fifth lens group G5, the image-side lenses are such that, at infinity, the position where the off-axis principal ray strikes the object-side lens surface is higher than the position where the on-axis edge ray strikes that lens surface. Therefore, in the zoom imaging optical system described in Embodiment 7, Lb becomes L18.

[0626] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0627] L25 becomes a lens that satisfies condition (13).

[0628] L25 becomes a lens that satisfies condition (14).

[0629] L25 becomes a lens that satisfies condition (15).

[0630] The following shows the specifications of the zoom imaging optical system involved in Example 7.

[0631] Numerical Example 7

[0632] Unit: mm

[0633] [Surface Data]

[0634]

[0635]

[0636]

[0637] [Various data]

[0638]

[0639] [Variable Interval Data]

[0640]

[0641]

[0642] [Lens Group Data]

[0643]

[0644] [Example 8]

[0645] Figure 92 This is a diagram of the lens structure of the zoom imaging optical system described in Example 8 when focusing at infinity at the wide-angle end.

[0646] Figure 92 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0647] Lens group G1 consists of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a convex meniscus lens with its convex surface facing the image side and a biconcave lens, and a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G6 consists of a biconcave lens, a convex meniscus lens with its convex surface facing the image side, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a combined lens of a biconvex lens L19, a biconvex lens L20, and a biconcave lens L21; a biconcave lens L22; a biconvex lens; a combined lens of a biconcave lens and a biconvex lens L25; a combined lens of a biconcave lens L26 and a biconvex lens L27; and a combined lens of a biconcave lens and a biconvex lens. Furthermore, it is possible to make the lenses in the seventh lens group G7 function as a vibration damping group by moving L20 to L22 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L20 to L22 can also be used as a vibration damping group.

[0648] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, the distance between the third lens group G3 and the fourth lens group G4 increases and then decreases, the distance between the first and sixth lens groups G4 increases relative to the wide-angle end at the telephoto end, the distance between the fourth lens group G4 and the fifth lens group G5 decreases, the distance between the fifth lens group G5 and the sixth lens group G6 increases, and the distance between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0649] Starting from L19 of the 7th lens group G7, the image-side lenses are those where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 8, Lb becomes L19.

[0650] L25 and L27 become lenses that satisfy conditions (11) and (12).

[0651] L19 and L26 become lenses that satisfy condition (13).

[0652] L19 and L26 become lenses that satisfy condition (14).

[0653] L19 and L26 become lenses that satisfy condition (15).

[0654] The following shows the specifications of the zoom imaging optical system involved in Example 8.

[0655] Numerical Example 8

[0656] Unit: mm

[0657] [Surface Data]

[0658]

[0659]

[0660]

[0661] [Various data]

[0662]

[0663] [Variable Interval Data]

[0664]

[0665]

[0666] [Lens Group Data]

[0667]

[0668] [Example 9]

[0669] Figure 105 This is a diagram of the lens structure of the zoom imaging optical system described in Example 9 when focusing at infinity at the wide-angle end.

[0670] Figure 105 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 is composed of a first lens group G1 with positive refractive power, the second front lens group GF2 is composed of a second lens group G2 with negative refractive power, the intermediate group GM is composed of a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR is composed of a seventh lens group G7 with negative refractive power.

[0671] Lens group G1 consists of a combined lens comprising a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a biconvex lens, a biconcave lens, a biconcave lens, and a convex meniscus lens with its convex surface facing the object side. Lens group G3 consists of a combined lens comprising a biconvex lens and a concave meniscus lens with its convex surface facing the image side. Lens group G4 consists of a combined lens comprising a concave meniscus lens with its convex surface facing the object side and a biconvex lens, a combined lens comprising a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens comprising a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G6 consists of a combined lens comprising a concave meniscus lens L17 with its convex surface facing the object side, a biconvex lens, and a concave meniscus lens L19 with its convex surface facing the image side. The seventh lens group G7 is composed of a combined lens consisting of a biconvex lens, a convex meniscus lens L21 with its convex surface facing the object side and a concave meniscus lens L22 with its convex surface facing the object side, a concave meniscus lens L23 with its convex surface facing the object side, a combined lens consisting of a biconvex lens and a biconcave lens and a convex meniscus lens L26 with its convex surface facing the object side, a concave meniscus lens L27 with its convex surface facing the object side and a biconvex lens, and a combined lens consisting of a biconcave lens and a biconvex lens. Furthermore, it is possible to make the seventh lens group G7 function as a vibration damping group by moving L21 to L23 integrally relative to the optical axis in a substantially perpendicular direction, but it is also possible to use lenses other than L21 to L23 as a vibration damping group.

[0672] When zooming from the wide-angle end to the telephoto end, the first lens group G1, the third lens group G3, and the seventh lens group G7 are fixed relative to the image plane. The second lens group G2 moves towards the image side. The fourth lens group G4 and the fifth lens group G5 move towards the object side along different trajectories. The sixth lens group G6 moves towards the object side and then towards the image side. The distance between the first lens group G1 and the second lens group G2 increases. The distance between the second lens group G2 and the third lens group G3 decreases. The distance between the third lens group G3 and the fourth lens group G4 decreases. The distance between the fourth lens group G4 and the fifth lens group G5 decreases and then increases. The distance between the wide-angle end and the telephoto end decreases relative to the wide-angle end. The distance between the fifth lens group G5 and the sixth lens group G6 increases. The distance between the sixth lens group G6 and the seventh lens group G7 increases and then decreases. The distance between the wide-angle end and the telephoto end becomes equal. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0673] The image-side lenses starting from L17 of the sixth lens group G6 are lenses in which, at infinity, the position where the off-axis principal ray enters the object-side lens surface is higher than the position where the on-axis edge ray enters the lens surface. Therefore, in the zoom imaging optical system according to Embodiment 9, Lb becomes L17.

[0674] L26 becomes a lens that satisfies conditions (11) and (12).

[0675] L17, L19 and L27 are lenses that satisfy condition (13).

[0676] L19 and L27 become lenses that satisfy condition (14).

[0677] L27 becomes a lens that satisfies condition (15).

[0678] The following shows the specifications of the zoom imaging optical system involved in Example 9.

[0679] Numerical Example 9

[0680] Unit: mm

[0681] [Surface Data]

[0682]

[0683]

[0684]

[0685] [Various data]

[0686]

[0687] [Variable Interval Data]

[0688]

[0689]

[0690] [Lens Group Data]

[0691]

[0692] [Example 10]

[0693] Figure 118 This is a diagram of the lens structure of the zoom imaging optical system described in Example 10 when focusing at infinity at the wide-angle end.

[0694] Figure 118 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0695] The first lens group G1 consists of a combined lens arranged sequentially from the object side, comprising a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens. The second lens group G2 consists of a combined lens comprising a convex meniscus lens with its convex surface facing the object side, a concave meniscus lens with its convex surface facing the object side, and a convex meniscus lens with its convex surface facing the object side, as well as a combined lens comprising a concave meniscus lens L8 with its convex surface facing the object side, a biconcave lens L9, and a biconvex lens L10. Furthermore, the second lens group G2 can function as a vibration damping group by moving L8 to L10 integrally relative to the optical axis in a substantially perpendicular direction; however, lenses other than L8 to L10 can also be used as a vibration damping group. Lens group G3 consists of a concave meniscus lens with its convex surface facing the object side, a combined lens of biconvex lenses, a convex meniscus lens with its convex surface facing the object side, a combined lens of a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, an aperture stop S, and a combined lens of biconvex and biconcave lenses. Lens group G4 consists of a combined lens of biconvex lenses and concave meniscus lenses with their convex surfaces facing the image side. Lens group G5 consists of a combined lens of biconvex lenses and biconcave lenses. Lens group G6 consists of a combined lens of biconvex lenses and concave meniscus lenses with their convex surfaces facing the image side, and a biconcave lens. Lens group G7 consists of a combined lens of biconvex lens L25 and biconcave lenses, a combined lens of concave meniscus lenses L27 and biconvex lenses L28 with their convex surfaces facing the object side.

[0696] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases, the interval between the fourth lens group G4 and the fifth lens group G5 decreases, and the interval between the fifth lens group G5 and the sixth lens group G6 increases and then decreases. The interval becomes larger relative to the wide-angle end at the telephoto end, and the interval between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0697] The image-side lenses starting from L25 of the 7th lens group G7 are lenses in which, at infinity, the position where the off-axis principal ray enters the object-side lens surface is higher than the position where the on-axis edge ray enters the lens surface. Therefore, in the zoom imaging optical system according to Embodiment 10, Lb becomes L25.

[0698] L25 and L28 become lenses that satisfy conditions (11) and (12).

[0699] L27 becomes a lens that satisfies condition (13).

[0700] L27 becomes a lens that satisfies condition (14).

[0701] L27 becomes a lens that satisfies condition (15).

[0702] The following shows the specifications of the zoom imaging optical system involved in Example 10.

[0703] Numerical Example 10

[0704] Unit: mm

[0705] [Surface Data]

[0706]

[0707]

[0708]

[0709] [Various data]

[0710]

[0711] [Variable Interval Data]

[0712]

[0713]

[0714] [Lens Group Data]

[0715]

[0716] [Example 11]

[0717] Figure 131 This is a diagram of the lens structure of the zoom imaging optical system described in Example 11 when focusing at infinity at the wide-angle end.

[0718] Figure 131 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, and a fifth lens group G5 with negative refractive power, and the subsequent group GR includes a sixth lens group G6 with negative refractive power.

[0719] Lens group G1 consists of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a plano-concave lens with its plane facing the object side, a biconcave lens, and a convex meniscus lens with its convex surface facing the object side. Lens group G3 consists of a biconvex lens and a plano-concave lens with its plane facing the image side. Lens group G4 consists of an aperture stop S, a biconvex lens, a combined lens of a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, a combined lens of a biconvex lens and a concave meniscus lens with its convex surface facing the image side, a combined lens of a convex meniscus lens L15 with its convex surface facing the image side and a biconcave lens L16, and a biconvex lens. Furthermore, the fourth lens group G4 can also function as a vibration damping group by moving L15 to L16 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L15 to L16 can also be used as vibration damping groups. The fifth lens group G5 is composed of a combined lens of a biconvex lens and a biconcave lens. The sixth lens group G6 is composed of a combined lens of a biconcave lens L20 and a biconvex lens, a combined lens of a biconcave lens L22 and a biconvex lens L23, and a combined lens of a biconcave lens and a biconvex lens.

[0720] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the sixth lens group G6 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third lens group G3 to the fifth lens group G5 move towards the object side along different trajectories. The distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, the distance between the third lens group G3 and the fourth lens group G4 decreases, the distance between the fourth lens group G4 and the fifth lens group G5 decreases, and the distance between the fifth lens group G5 and the sixth lens group G6 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0721] The image-side lenses starting from L20 of the sixth lens group G6 are lenses in which, at infinity, the position where the off-axis principal ray enters the object-side lens surface is higher than the position where the on-axis edge ray enters the lens surface. Therefore, in the zoom imaging optical system according to Embodiment 11, Lb becomes L20.

[0722] L23 becomes a lens that satisfies conditions (11) and (12).

[0723] L22 becomes a lens that satisfies condition (13).

[0724] L22 becomes a lens that satisfies condition (14).

[0725] L22 becomes a lens that satisfies condition (15).

[0726] The following shows the specifications of the zoom imaging optical system involved in Example 11.

[0727] Numerical Example 11

[0728] Unit: mm

[0729] [Surface Data]

[0730]

[0731]

[0732] [Various data]

[0733]

[0734] [Variable Interval Data]

[0735]

[0736]

[0737] [Lens Group Data]

[0738]

[0739] [Example 12]

[0740] Figure 144 This is a diagram of the lens structure of the zoom imaging optical system described in Example 12 when focusing at infinity at the wide-angle end.

[0741] Figure 144 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with negative refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0742] Lens group G1 consists of a combined lens comprising a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a biconvex lens, a biconcave lens, a biconcave lens, and a combined lens comprising a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the image side. Lens group G4 consists of a biconvex lens, a combined lens comprising a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens comprising a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G6 consists of a combined lens comprising a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a combined lens consisting of a convex meniscus lens L19 with its convex surface facing the object side, a biconvex lens L20 and a biconcave lens L21, a concave meniscus lens L22 with its convex surface facing the object side, a biconvex lens, a combined lens consisting of a biconcave lens and a biconvex lens, a combined lens consisting of a biconcave lens L26 and a biconvex lens L27, and a combined lens consisting of a concave meniscus lens with its convex surface facing the object side and a convex meniscus lens with its convex surface facing the object side. Furthermore, it is possible to make L20 to L22 in the seventh lens group G7 function as a vibration damping group by moving them integrally relative to the optical axis in a substantially perpendicular direction, but it is also possible to use lenses other than L20 to L22 as a vibration damping group.

[0743] When zooming from the wide-angle end to the telephoto end, the first lens group G1, the third lens G3, and the seventh lens group G7 are fixed relative to the image plane. The second lens group G2 moves towards the image side, and the fourth to sixth lens groups G4 move towards the object side along different trajectories. The distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, the distance between the third lens group G3 and the fourth lens group G4 decreases, the distance between the fourth lens group G4 and the fifth lens group G5 decreases, the distance between the fifth lens group G5 and the sixth lens group G6 increases, and the distance between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0744] Starting from L19 of the 7th lens group G7, the image-side lenses are such that, at infinity, the position where the off-axis principal ray strikes the object-side lens surface is higher than the position where the on-axis edge ray strikes that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 12, Lb becomes L19.

[0745] L27 becomes a lens that satisfies conditions (11) and (12).

[0746] L26 becomes a lens that satisfies condition (13).

[0747] L26 becomes a lens that satisfies condition (14).

[0748] L26 becomes a lens that satisfies condition (15).

[0749] The following shows the specifications of the zoom imaging optical system involved in Example 12.

[0750] Numerical Example 12

[0751] Unit: mm

[0752] [Surface Data]

[0753]

[0754]

[0755] [Various data]

[0756]

[0757] [Variable Interval Data]

[0758]

[0759]

[0760] [Lens Group Data]

[0761]

[0762] [Example 13]

[0763] Figure 157 This is a diagram of the lens structure of the zoom imaging optical system described in Example 13 when focusing at infinity at the wide-angle end.

[0764] Figure 157 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with negative refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0765] Lens group G1 consists of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a biconvex lens and a biconcave lens, and a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G6 consists of a concave meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens. The seventh lens group G7 is composed of a biconvex lens L19, a combined lens consisting of a convex meniscus lens L20 with its convex surface facing the image side and a biconcave lens L21, a combined lens consisting of a biconvex lens and a biconcave lens, a combined lens consisting of a biconvex lens L24, a biconcave lens L25, and a biconvex lens L26, and a combined lens consisting of a biconcave lens and a biconvex lens. Furthermore, it is possible to make the seventh lens group G7 function as an anti-vibration group by moving L20 to L21 integrally relative to the optical axis in a substantially perpendicular direction, but it is also possible to use lenses other than L20 to L21 as an anti-vibration group.

[0766] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third to sixth lens groups G6 move towards the object side along different trajectories. The interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases and then decreases, and the interval becomes smaller relative to the wide-angle end at the telephoto end. The interval between the fourth lens group G4 and the fifth lens group G5 decreases, the interval between the fifth lens group G5 and the sixth lens group G6 increases, and the interval between the sixth lens group G6 and the seventh lens group G7 increases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0767] Starting from L19 of the 7th lens group G7, the image-side lenses are those where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 13, Lb becomes L19.

[0768] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0769] L25 becomes a lens that satisfies condition (13).

[0770] L25 becomes a lens that satisfies condition (14).

[0771] L25 becomes a lens that satisfies condition (15).

[0772] The following shows the specifications of the zoom imaging optical system involved in Example 13.

[0773] Numerical Example 13

[0774] Unit: mm

[0775] [Surface Data]

[0776]

[0777]

[0778] [Aspherical Data]

[0779]

[0780] [Various data]

[0781]

[0782] [Variable Interval Data]

[0783]

[0784]

[0785] [Lens Group Data]

[0786]

[0787] [Example 14]

[0788] Figure 170 This is a diagram of the lens structure of the zoom imaging optical system described in Example 14 when focusing at infinity at the wide-angle end.

[0789] Figure 170 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, a sixth lens group G6 with positive refractive power, and a seventh lens group G7 with positive refractive power, and the subsequent group GR includes an eighth lens group G8 with negative refractive power.

[0790] Lens group G1 consists of a combined lens consisting of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a convex meniscus lens with its convex surface facing the object side, and a concave meniscus lens with its convex surface facing the object side, arranged sequentially from the object side, and a convex meniscus lens with its convex surface facing the object side. Lens group G2 consists of a combined lens consisting of a biconvex lens and a biconcave lens, and a combined lens consisting of a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a combined lens consisting of a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens consisting of a biconvex lens and a biconcave lens. Lens group G6 consists of a combined lens consisting of a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. Lens group G7 consists of a biconvex lens L20. The eighth lens group G8 is composed of a combined lens of a biconvex lens L21 and a biconcave lens L22, a biconcave lens L23, a combined lens of a biconvex lens and a biconcave lens, a combined lens of a biconvex lens L26, a biconcave lens L27 and a biconvex lens L28, and a combined lens of a biconcave lens and a biconvex lens. Furthermore, it can function as a vibration damping group by moving L21 to L23 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L21 to L23 can also be used as a vibration damping group.

[0791] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the eighth lens group G8 are fixed relative to the image plane. The second lens group moves towards the image side. The third to sixth lens groups G3 move towards the object side along different trajectories. The seventh lens group G7 moves towards the image side. The distance between the first lens group G1 and the second lens group G2 increases. The distance between the second lens group G2 and the third lens group G3 decreases. The distance between the third lens group G3 and the fourth lens group G4 increases. The distance between the fourth lens group G4 and the fifth lens group G5 decreases. The distance between the fifth lens group G5 and the sixth lens group G6 increases. The distance between the sixth lens group G6 and the seventh lens group G7 increases. The distance between the seventh lens group G7 and the eighth lens group G8 decreases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side, and the seventh lens group G7 moves towards the object side.

[0792] Lenses on the image side starting from L20 of the 7th lens group G7 become lenses where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 14, Lb becomes L20.

[0793] L26 and L28 become lenses that satisfy conditions (11) and (12).

[0794] L27 becomes a lens that satisfies condition (13).

[0795] L27 becomes a lens that satisfies condition (14).

[0796] L27 becomes a lens that satisfies condition (15).

[0797] The following shows the specifications of the zoom imaging optical system involved in Example 14.

[0798] Numerical Example 14

[0799] Unit: mm

[0800] [Surface Data]

[0801]

[0802]

[0803]

[0804] [Various data]

[0805]

[0806] [Variable Interval Data]

[0807]

[0808]

[0809] [Lens Group Data]

[0810]

[0811] [Example 15]

[0812] Figure 183 This is a diagram of the lens structure of the zoom imaging optical system described in Example 15 when focusing at infinity at the wide-angle end.

[0813] Figure 183 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power. The second front lens group GF2 consists of a second lens group G2 with negative refractive power and a third lens group G3 with negative refractive power, and the whole has negative refractive power. The intermediate group GM includes a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, a sixth lens group G6 with positive refractive power, and a seventh lens group G7 with positive refractive power. The subsequent group GR includes an eighth lens group G8 with negative refractive power.

[0814] Lens group G1 consists of a combined lens comprising a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a combined lens comprising a biconvex lens and a biconcave lens. Lens group G3 consists of a combined lens comprising a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a concave meniscus lens with its convex surface facing the object side, a biconvex lens, a combined lens comprising a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens comprising a biconvex lens and a biconcave lens. Lens group G6 consists of a combined lens comprising a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. Lens group G7 consists of a biconvex lens L19. The eighth lens group G8 is composed of a combined lens of a biconvex lens L20 and a biconcave lens L21, a biconcave lens L22, a combined lens of a biconvex lens and a biconcave lens, a combined lens of a biconvex lens L25, a biconcave lens L26, and a biconvex lens L27, and a combined lens of a biconcave lens and a biconvex lens. Furthermore, it can function as a vibration damping group by moving L20 to L22 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L20 to L22 can also be used as vibration damping groups.

[0815] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the eighth lens group G8 are fixed relative to the image plane. The second lens group G2 and the third lens group G3 move towards the image side along different trajectories. The fourth to sixth lens groups G4 move towards the object side along different trajectories. The seventh lens group G7 moves towards the object side and then towards the image side. The distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, and the distance between the third lens group G3 and the fourth lens group G4 decreases. The spacing between lens group G4 and lens group G5 decreases and then increases, resulting in a smaller spacing at the telephoto end relative to the wide-angle end. The spacing between lens group G5 and lens group G6 increases. The spacing between lens group G6 and lens group G7 decreases and then increases, resulting in a larger spacing at the telephoto end relative to the wide-angle end. The spacing between lens group G7 and lens group G8 increases and then decreases, resulting in a smaller spacing at the telephoto end relative to the wide-angle end. When focusing from an object at infinity to a closer object, lens group G5 moves towards the image side, and lens group G7 moves towards the object side.

[0816] Starting from L19 of the 7th lens group G7, the image-side lenses are such that, at infinity, the position where the off-axis principal ray strikes the object-side lens surface is higher than the position where the on-axis edge ray strikes that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 15, Lb becomes L19.

[0817] L25 and L27 become lenses that satisfy conditions (11) and (12).

[0818] L26 becomes a lens that satisfies condition (13).

[0819] L26 becomes a lens that satisfies condition (14).

[0820] L26 becomes a lens that satisfies condition (15).

[0821] The following shows the specifications of the zoom imaging optical system involved in Example 15.

[0822] Numerical Example 15

[0823] Unit: mm

[0824] [Surface Data]

[0825]

[0826]

[0827] [Various data]

[0828]

[0829] [Variable Interval Data]

[0830]

[0831]

[0832] [Lens Group Data]

[0833]

[0834] [Example 16]

[0835] Figure 196 This is a diagram of the lens structure of the zoom imaging optical system described in Example 16 when focusing at infinity at the wide-angle end.

[0836] Figure 196 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0837] Lens group G1 consists of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a concave meniscus lens with its convex surface facing the object side, a biconcave lens, and a convex meniscus lens with its convex surface facing the object side. Lens group G3 consists of a biconvex lens and a plano-concave lens with its plane facing the image side. Lens group G4 consists of an aperture stop S, a biconvex lens, a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, a biconvex lens L and a concave meniscus lens with its convex surface facing the image side, a convex meniscus lens L15 with its convex surface facing the image side and a biconcave lens L16, and a biconvex lens. Furthermore, the fourth lens group G4 can also function as a vibration damping group by moving L15 to L16 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L15 to L16 can also be used as vibration damping groups. The fifth lens group G5 is composed of a combined lens of a biconvex lens and a biconcave lens. The sixth lens group G6 is composed of a combined lens of a biconcave lens L20 and a biconvex lens. The seventh lens group G7 is composed of a combined lens of a biconcave lens L22 and a biconvex lens L23, and a combined lens of a biconcave lens and a biconvex lens.

[0838] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the seventh lens group G7 are fixed relative to the image plane, the second lens group G2 moves towards the image side, the third lens group G3 to the fifth lens group G5 move towards the object side along different trajectories, the sixth lens group G6 moves towards the image side, the interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 decreases, the interval between the fourth lens group G4 and the fifth lens group G5 decreases, the interval between the fifth lens group G5 and the sixth lens group G6 increases, and the interval between the sixth lens group G6 and the seventh lens group G7 decreases. When focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side, and the sixth lens group G6 moves towards the object side.

[0839] The image-side lenses starting from L20 of the sixth lens group G6 become lenses where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 16, Lb becomes L20.

[0840] L23 becomes a lens that satisfies conditions (11) and (12).

[0841] L22 becomes a lens that satisfies condition (13).

[0842] L22 becomes a lens that satisfies condition (14).

[0843] L22 becomes a lens that satisfies condition (15).

[0844] The following shows the specifications of the zoom imaging optical system involved in Example 16.

[0845] Numerical Example 16

[0846] Unit: mm

[0847] [Surface Data]

[0848]

[0849]

[0850] [Various data]

[0851]

[0852] [Variable Interval Data]

[0853]

[0854]

[0855] [Lens Group Data]

[0856]

[0857] [Example 17]

[0858] Figure 209 This is a diagram of the lens structure of the zoom imaging optical system described in Example 17 when focusing at infinity at the wide-angle end.

[0859] Figure 209 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power and a fourth lens group G4 with negative refractive power, and the subsequent group GR includes a fifth lens group G5 with negative refractive power.

[0860] Lens group G1 consists of a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a biconvex lens, and a biconcave lens arranged sequentially from the object side. Lens group G2 consists of a biconcave lens, a biconcave lens, and a convex meniscus lens with its convex surface facing the object side. Lens group G3 consists of a biconvex lens, a concave meniscus lens with its convex surface facing the image side, an aperture stop S, a convex meniscus lens with its convex surface facing the object side, a convex meniscus lens with its convex surface facing the object side and a concave meniscus lens with its convex surface facing the object side, a biconvex lens and a concave meniscus lens with its convex surface facing the image side, a convex meniscus lens L15 with its convex surface facing the image side and a biconcave lens L16, and a biconvex lens. Furthermore, the third lens group G3 can also function as a vibration damping group by moving L15 to L16 integrally relative to the optical axis in a substantially perpendicular direction, but lenses other than L15 to L16 can also be used as vibration damping groups. The fourth lens group G4 is composed of a combined lens of a biconvex lens and a biconcave lens. The fifth lens group G5 is composed of a combined lens of a biconcave lens L20 and a biconvex lens, a combined lens of a biconcave lens L22 and a biconvex lens L23, and a combined lens of a biconcave lens and a biconvex lens.

[0861] When zooming from the wide-angle end to the telephoto end, the first lens group G1 and the fifth lens group G5 are fixed relative to the image plane, the second lens group G2 moves towards the image side, and the third lens group G3 and the fourth lens group G4 move towards the object side along different trajectories. The distance between the first lens group G1 and the second lens group G2 increases, the distance between the second lens group G2 and the third lens group G3 decreases, the distance between the third lens group G3 and the fourth lens group G4 decreases, and the distance between the fourth lens group G4 and the fifth lens group G5 increases. When focusing from an object at infinity to a closer object, the fourth lens group G4 moves towards the image side.

[0862] The image-side lenses starting from L20 of the fifth lens group G5 become lenses where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 17, Lb becomes L20.

[0863] L23 becomes a lens that satisfies conditions (11) and (12).

[0864] L22 becomes a lens that satisfies condition (13).

[0865] L22 becomes a lens that satisfies condition (14).

[0866] L22 becomes a lens that satisfies condition (15).

[0867] The following shows the specifications of the zoom imaging optical system involved in Example 17.

[0868] Numerical Example 17

[0869] Unit: mm

[0870] [Surface Data]

[0871]

[0872]

[0873] [Various data]

[0874]

[0875] [Variable Interval Data]

[0876]

[0877]

[0878] [Lens Group Data]

[0879]

[0880] [Example 18]

[0881] Figure 222 This is a diagram of the lens structure of the zoom imaging optical system described in Example 18 when focusing at infinity at the wide-angle end.

[0882] Figure 222 The zoom imaging optical system includes a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 includes a first lens group G1 with positive refractive power, the second front lens group GF2 includes a second lens group G2 with negative refractive power, the intermediate group GM includes a third lens group G3 with positive refractive power, a fourth lens group G4 with positive refractive power, a fifth lens group G5 with negative refractive power, and a sixth lens group G6 with positive refractive power, and the subsequent group GR includes a seventh lens group G7 with negative refractive power.

[0883] Lens group G1 consists of a combined lens comprising a biconvex lens, a convex meniscus lens with its convex surface facing the object side, a convex meniscus lens with its convex surface facing the object side, and a concave meniscus lens with its convex surface facing the object side, arranged sequentially from the object side. Lens group G2 consists of a combined lens comprising a biconvex lens and a biconcave lens, and a combined lens comprising a biconcave lens and a biconvex lens. Lens group G3 consists of a biconvex lens and a concave meniscus lens with its convex surface facing the object side. Lens group G4 consists of a biconvex lens, a combined lens comprising a biconvex lens and a concave meniscus lens with its convex surface facing the image side, and an aperture stop S. Lens group G5 consists of a combined lens comprising a biconcave lens and a convex meniscus lens with its convex surface facing the object side. Lens group G6 consists of a combined lens comprising a biconcave lens, a biconvex lens, and a concave meniscus lens with its convex surface facing the image side. The seventh lens group G7 is composed of a convex meniscus lens L19 with its convex surface facing the object side, a convex meniscus lens L20 with its convex surface facing the image side, a combined lens of a biconvex and biconcave lens L21, a combined lens of a biconvex and biconcave lens, a combined lens of a biconvex lens L24, a biconcave lens L25, and a biconvex lens L26, and a combined lens of a biconcave and biconvex lens. Furthermore, it is possible to make the seventh lens group G7 function as a vibration damping group by moving L20 to L21 integrally relative to the optical axis in a substantially perpendicular direction, but it is also possible to use lenses other than L20 to L21 as a vibration damping group.

[0884] When zooming from the wide-angle end to the telephoto end, the first lens group G1 moves towards the object side, the second lens group G2 moves towards the image side and then towards the object side, the third lens group G3 to the sixth lens group G6 move towards the object side along different trajectories, the seventh lens group G7 is fixed relative to the image plane, the interval between the first lens group G1 and the second lens group G2 increases, the interval between the second lens group G2 and the third lens group G3 decreases, the interval between the third lens group G3 and the fourth lens group G4 increases and then decreases, the interval at the telephoto end increases relative to the wide-angle end, the interval between the fourth lens group G4 and the fifth lens group G5 decreases and then increases, the interval at the telephoto end decreases relative to the wide-angle end, the interval between the fifth lens group G5 and the sixth lens group G6 increases, the interval between the sixth lens group G6 and the seventh lens group G7 increases, when focusing from an object at infinity to a closer object, the fifth lens group G5 moves towards the image side.

[0885] Starting from L19 of the 7th lens group G7, the image-side lenses are those where, at infinity, the position of the off-axis principal ray incident on the object-side lens surface is higher than the position of the on-axis edge ray incident on that lens surface. Therefore, in the zoom imaging optical system according to Embodiment 18, Lb becomes L19.

[0886] L24 and L26 become lenses that satisfy conditions (11) and (12).

[0887] L25 becomes a lens that satisfies condition (13).

[0888] L25 becomes a lens that satisfies condition (14).

[0889] L25 becomes a lens that satisfies condition (15).

[0890] The following shows the specifications of the zoom imaging optical system involved in Example 18.

[0891] Numerical Example 18

[0892] Unit: mm

[0893] [Surface Data]

[0894]

[0895]

[0896] [Various data]

[0897]

[0898] [Variable Interval Data]

[0899]

[0900]

[0901] [Lens Group Data]

[0902]

[0903] The following is a list of the corresponding values ​​of the conditional expressions in the above embodiments.

[0904]

[0905]

[0906]

[0907] <Other Implementation Methods>

[0908] The technology disclosed in this embodiment is not limited to the above-described embodiments and descriptions, and various modifications can be implemented. The shapes and values ​​of the parts shown in the above numerical embodiments are merely examples for implementing this technology, and the scope of this technology is not to be interpreted as limited by these shapes and values.

[0909] This technology can also adopt the following structure.

[0910] [Item 1]

[0911] A zoom imaging optical system is characterized by comprising a first front lens group GF1, a second front lens group GF2, an intermediate group GM, and a subsequent group GR arranged sequentially from the object side. The first front lens group GF1 comprises one or two lens groups and has positive refractive power overall. The second front lens group GF2 comprises one or more lens groups and has negative refractive power overall. The intermediate group GM comprises one or more lens groups. The first front lens group GF1 has a first lens group G1 at the position closest to the object side. An aperture stop S is positioned closer to the image side than the second front lens group GF2. The second front lens group GF2 has the lens group with the strongest negative refractive power among the lens groups positioned closer to the object side than the aperture stop S. The spacing between adjacent lens groups changes during zooming or focusing. When zooming from the wide-angle end to the telephoto end (wherein, when focusing on an object at infinity), the lens group with the strongest negative refractive power among the lens groups constituting the second front lens group GF2 moves towards the image side and satisfies the following condition.

[0912] (1) 2.50 < fT / fF1 < 11.00

[0913] (2) 0.15 < LiT / fT < 0.70

[0914] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0915] fF1: Focal length of the first front lens group GF1 at infinity.

[0916] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0917] [Item 2]

[0918] The zoom imaging optical system according to [item 1] is characterized in that,

[0919] The first lens group G1 satisfies the following condition.

[0920] (3) 2.50 < fT / f1 < 11.00

[0921] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0922] f1: Focal length of the first lens group G1

[0923] [Item 3]

[0924] The zoom imaging optical system according to [Item 1] or [Item 2] is characterized in that,

[0925] The following condition is satisfied.

[0926] (4) 1.2 < fT / fW < 7.0

[0927] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0928] fW: Focal length of the entire system at infinity wide-angle end

[0929] [Item 4]

[0930] The zoom imaging optical system according to any one of [Item 1] to [Item 3] is characterized in that,

[0931] The following condition is satisfied.

[0932] (5) 60<LiT / (fT / fW)<250

[0933] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[0934] fW: Focal length of the entire system at infinity wide-angle end

[0935] fT: The focal length of the entire system when looking at the farthest point at infinity.

[0936] [Item 5]

[0937] The zoom imaging optical system according to any one of [Item 1] to [Item 4] is characterized in that,

[0938] The first lens group G1 is fixed relative to the image plane when zooming from the wide-angle end to the telephoto end.

[0939] [Item 6]

[0940] The zoom imaging optical system according to any one of [Item 1] to [Item 5] is characterized in that,

[0941] The first front lens group GF1 satisfies the following condition.

[0942] (6) 1.5 < fF1 / ΦS1T < 5.0

[0943] fF1: Focal length of the first front lens group GF1 at infinity.

[0944] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[0945] [Item 7]

[0946] The zoom imaging optical system according to any one of [Item 1] to [Item 6] is characterized in that,

[0947] The first front lens group GF1 satisfies the following condition.

[0948] (7)0.40<ΦG1FrT / ΦS1T<0.87

[0949] ΦG1FrT: The diameter of the on-axis edge ray on the image-side plane of the first front lens group GF1 when viewing at infinity.

[0950] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[0951] [Item 8]

[0952] The zoom imaging optical system according to any one of [Item 1] to [Item 7] is characterized in that,

[0953] The following condition is satisfied.

[0954] (8) 0.08 < LGF1 / LrT < 0.50

[0955] LGF1: The length of the optical axis of the first front lens group GF1 when viewing at infinity.

[0956] LrT: The length of the optical axis from the lens surface closest to the object to the lens surface closest to the image when viewed at infinity.

[0957] [Item 9]

[0958] The zoom imaging optical system according to any one of [Item 1] to [Item 8] is characterized in that,

[0959] The first front lens group GF1 satisfies the following condition.

[0960] (9)0.15<LairGF1 / LGF1<0.83

[0961] LairGF1: The largest air gap on the optical axis within the first front lens group GF1 when viewing at infinity.

[0962] LGF1: The length of the optical axis of the first front lens group GF1 when viewing at infinity.

[0963] [Item 10]

[0964] The zoom imaging optical system according to any one of [Item 1] to [Item 9] is characterized in that,

[0965] The first front lens group GF1 has a convex lens positioned closest to the object and a concave lens positioned closest to the image.

[0966] [Item 11]

[0967] The zoom imaging optical system according to any one of [Item 1] to [Item 10] is characterized in that,

[0968] The first front lens group GF1 has a convex lens positioned closest to the object and satisfies the following condition.

[0969] (10)0.20<LairGF1 / LgGF1<3.50

[0970] LairGF1: The largest air gap on the optical axis within the first front lens group GF1 when viewing at infinity.

[0971] LgGF1: The total thickness along the optical axis of all lenses constituting the first front lens group GF1.

[0972] [Item 12]

[0973] The zoom imaging optical system according to any one of [Item 1] to [Item 11] is characterized in that,

[0974] The subsequent group GR has one or more convex lenses that satisfy the following condition.

[0975] (11)0.00<(-0.01176×vdpLgr-ndpLgr+2.2719) / (((-0.01176)^2+(2.2719)^2)^(1 / 2))

[0976] (12) ΔPgFpLgr<-0.0010

[0977] vdpLgr: The Abbe number of the convex lens possessed by the subsequent group GR.

[0978] ndpLgr: The refractive index of the convex lens possessed by the subsequent group GR.

[0979] ΔPgFpLgr: Anomalous dispersion of the convex lens possessed by the subsequent group GR

[0980] [Item 13]

[0981] The zoom imaging optical system according to any one of [Item 1] to [Item 12] is characterized in that,

[0982] Let Lb be the lens that is positioned closest to the object side, and is located on the image side of the lens that, when viewed from infinity, has an off-axis principal ray incident on the object side at a position higher than the position on the upper edge ray incident on that lens surface. Then, one or more concave lenses satisfying the following condition are arranged on the image side starting from Lb.

[0983] (13) ΔPgFnLbr>0.009

[0984] ΔPgFnLbr: Anomalous dispersion of a concave lens positioned on the image side, starting from lens Lb.

[0985] [Item 14]

[0986] The zoom imaging optical system according to any one of [Item 1] to [Item 13] is characterized in that,

[0987] Let Lb be the lens that is positioned closest to the object side, and is located on the image side of the lens that, when viewed from infinity, has an off-axis principal ray incident on the object side at a position higher than the position on the upper edge ray incident on the lens surface. Let Lb be the lens that is positioned closest to the object side. Let Lb be the lens that satisfies the following condition. Let Lb be the lens that is positioned on the image side of the lens.

[0988] (14) vdnLbr×ΔPgFnLbr>0.8

[0989] vdnLbr: The Abbe number of a concave lens positioned on the image side, starting from lens Lb.

[0990] ΔPgFnLbr: Anomalous dispersion of a concave lens positioned on the image side, starting from lens Lb.

[0991] [Item 15]

[0992] The zoom imaging optical system according to any one of [Item 1] to [Item 14] is characterized in that,

[0993] The subsequent group GR has one or more concave lenses that satisfy the following condition.

[0994] (15) vdnLgr×ΔPgFnLgr>0.8

[0995] vdnLgr: The Abbe number of the concave lens possessed by the subsequent group GR.

[0996] ΔPgFnLgr: Anomalous dispersion of the concave lens possessed by the subsequent group GR

[0997] [Item 16]

[0998] The zoom imaging optical system according to any one of [Item 1] to [Item 15] is characterized in that,

[0999] The following condition is satisfied.

[1000] (16) 4.5 < fT / BFT < 130

[1001] fT: The focal length of the entire system when looking at the farthest point at infinity.

[1002] BFT: The length of the optical axis from the lens surface closest to the image side to the image plane when looking at the farthest point at infinity.

[1003] [Item 17]

[1004] The zoom imaging optical system according to any one of [Item 1] to [Item 16] is characterized in that,

[1005] The following condition is satisfied.

[1006] (17) 4.0 < LiT / BFT < 35.0

[1007] LiT: The length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity.

[1008] BFT: The length of the optical axis from the lens surface closest to the image side to the image plane when looking at the farthest point at infinity.

[1009] [Item 18]

[1010] The zoom imaging optical system according to any one of [Item 1] to [Item 17] is characterized in that,

[1011] All convex lenses constituting the first front lens group GF1 satisfy the following conditional expression.

[1012] (18) ΔPgFpGF1>0.000

[1013] ΔPgFpGF1: Anomalous dispersion of the convex lens possessed by the first front lens group GF1.

[1014] [Item 19]

[1015] The zoom imaging optical system according to any one of [Item 1] to [Item 18] is characterized in that,

[1016] All convex lenses constituting the first front lens group GF1 satisfy the following conditional expression.

[1017] (19) ndpGF1 < 1.68

[1018] ndpGF1: The refractive index of the convex lens possessed by the first front lens group GF1.

[1019] [Item 20]

[1020] The zoom imaging optical system according to any one of [Item 1] to [Item 19] is characterized in that,

[1021] The following condition is satisfied.

[1022] (20) -75.0 < fT / fF2 < -5.0

[1023] fT: The focal length of the entire system when looking at the farthest point at infinity.

[1024] fF2: Focal length of the second front lens group GF2 at infinity.

[1025] [Item 21]

[1026] The zoom imaging optical system according to any one of [Item 1] to [Item 20] is characterized in that,

[1027] The following condition is satisfied.

[1028] (21) -7.0 < fF1 / fF2 < -2.0

[1029] fF1: Focal length of the first front lens group GF1 at infinity.

[1030] fF2: Focal length of the second front lens group GF2 at infinity.

[1031] [Item 22]

[1032] The zoom imaging optical system according to any one of [Item 2] to [Item 21] is characterized in that,

[1033] The following condition is satisfied.

[1034] (22)0.20<ΦG2FfT / ΦS1T<0.60

[1035] ΦG2FfT: The diameter of the on-axis edge ray on the surface closest to the object in the second front lens group GF2 when viewing at infinity.

[1036] ΦS1T: The diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

[1037] [Item 23]

[1038] The zoom imaging optical system according to any one of [Item 1] to [Item 22] is characterized in that,

[1039] In the case where the first front lens group GF1 includes two lens groups, the image-side lens group moves toward the object side when zooming from the wide-angle end to the telephoto end.

[1040] [Item 24]

[1041] The zoom imaging optical system according to any one of [Item 1] to [Item 23] is characterized in that,

[1042] When the first front lens group GF1 includes two lens groups, the distance between the image-side lens group and the first lens group G1 located on the object side decreases and the distance between the image-side lens group and the second front lens group GF2 located on the image side increases when zooming from the wide-angle end to the telephoto end.

[1043] [Item 25]

[1044] The zoom imaging optical system according to any one of [Item 1] to [Item 24] is characterized in that,

[1045] At least one of the lens groups constituting the intermediate group GM moves along the optical axis when focusing from an object at infinity to a closer object.

[1046] [Item 26]

[1047] The zoom imaging optical system according to any one of [Item 1] to [Item 25] is characterized in that,

[1048] It does not have diffractive optical elements.

[1049] [Item 27]

[1050] The zoom imaging optical system according to any one of [Item 1] to [Item 26] is characterized in that,

[1051] All the lens groups that make up the second front lens group GF2 move toward the image side when zooming from the wide-angle end to the telephoto end.

[1052] [Item 28]

[1053] The zoom imaging optical system according to any one of [Item 1] to [Item 27] ​​is characterized in that,

[1054] The subsequent group GR is fixed relative to the image plane when zooming from the wide-angle end to the telephoto end.

[1055] Anyone skilled in the art can certainly conceive of various modifications, combinations, sub-combinations, and alterations based on design requirements or other factors, but these are included within the scope of the appended technical solution or its equivalent.

[1056] Symbol Explanation

[1057] G1 - Lens Group 1, G2 - Lens Group 2, G3 - Lens Group 3, G4 - Lens Group 4, G5 - Lens Group 5, G6 - Lens Group 6, G7 - Lens Group 7, GF1 - Front Lens Group 1, GF2 - Front Lens Group 2, GM - Intermediate Group, GR - Subsequent Group, S - Aperture Stop, F - Filter, I - Image Plane.

Claims

1. A zoom imaging optical system, characterized in that, It includes a first anterior lens group (GF1), a second anterior lens group (GF2), an intermediate group (GM), and a subsequent group (GR) arranged sequentially from the object side. The first anterior lens group (GF1) comprises one or two lens groups and has positive refractive power overall. The second anterior lens group (GF2) comprises one or more lens groups and has negative refractive power overall. The intermediate group (GM) comprises one or more lens groups. The first front lens group (GF1) has the first lens group (G1) at the position closest to the object. The aperture stop (S) is positioned further to the image side than the second front lens group (GF2). The second front lens group (GF2) is the lens group with the strongest negative refractive power among the lens groups, which is positioned further to the object side than the aperture stop (S). The spacing between adjacent lens groups changes when zooming or focusing. When focusing on an object at infinity at zoom level from the wide-angle end to the telephoto end, the lens group with the greatest negative refractive power in the second front lens group (GF2) moves towards the image side. A zoom imaging optical system satisfies the following condition. (1) 2.50 < fT / fF1 < 11.00 (2) 0.15 < LiT / fT < 0.70 fT is the focal length of the entire system when looking at the far end at infinity. fF1 is the focal length of the first front lens group (GF1) when viewed at infinity. LiT is the length of the optical axis from the lens surface closest to the object to the image plane when looking at the far end at infinity.

2. The zoom imaging optical system according to claim 1, characterized in that, The first lens group (G1) satisfies the following condition: (3) 2.50 < fT / f1 < 11.00 fT is the focal length of the entire system when looking at the far end at infinity. f1 is the focal length of the first lens group (G1).

3. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (4) 1.2 < fT / fW < 7.0 fT is the focal length of the entire system when looking at the far end at infinity. fW is the focal length of the entire system at the infinity wide-angle end.

4. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (5) 60<LiT / (fT / fW)<250 LiT is the length of the optical axis from the lens surface closest to the object to the image plane when looking at the farthest point at infinity. fW is the focal length of the entire system at the infinity wide-angle end. fT is the focal length of the entire system when looking at the far end at infinity.

5. The zoom imaging optical system according to claim 1, characterized in that, When zooming from the wide-angle end to the telephoto end, the first lens group (G1) is fixed relative to the image plane.

6. The zoom imaging optical system according to claim 1, characterized in that, The first front lens group (GF1) satisfies the following condition: (6) 1.5 < fF1 / ΦS1T < 5.0 fF1 is the focal length of the first front lens group (GF1) when viewed at infinity. ΦS1T is the diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

7. The zoom imaging optical system according to claim 1, characterized in that, The first front lens group (GF1) satisfies the following condition: (7)0.40<ΦG1FrT / ΦS1T<0.87 ΦG1FrT is the diameter of the on-axis edge ray on the image-side plane of the first front lens group (GF1) when viewing at infinity. ΦS1T is the diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

8. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (8) 0.08 < LGF1 / LrT < 0.50 LGF1 is the length on the optical axis of the first front lens group (GF1) when viewed from infinity. LrT is the length of the optical axis from the lens surface closest to the object to the lens surface closest to the image when viewed from infinity.

9. The zoom imaging optical system according to claim 1, characterized in that, The first front lens group (GF1) satisfies the following condition: (9)0.15<LairGF1 / LGF1<0.83 LairGF1 is the largest air gap on the optical axis within the first front lens group (GF1) at infinity telescope. LGF1 is the length on the optical axis of the first front lens group (GF1) when viewed from infinity.

10. The zoom imaging optical system according to claim 1, characterized in that, The first front lens group (GF1) has a convex lens positioned closest to the object and a concave lens positioned closest to the image.

11. The zoom imaging optical system according to claim 1, characterized in that, The first front lens group (GF1) has a convex lens positioned closest to the object and satisfies the following condition: (10)0.20<LairGF1 / LgGF1<3.50 LairGF1 is the largest air gap on the optical axis within the first front lens group (GF1) at infinity telescope. LgGF1 is the sum of the thicknesses on the optical axis of all the lenses that make up the first front lens group (GF1).

12. The zoom imaging optical system according to claim 1, characterized in that, The subsequent group (GR) has one or more convex lenses that satisfy the following condition. (11)0.00<(-0.01176×vdpLgr-ndpLgr+2.2719) / (((-0.01176)^2+(2.2719)^2)^(1 / 2)) (12) ΔPgFpLgr<-0.0010 vdpLgr is the Abbe number of the convex lens possessed by the subsequent group (GR). ndpLgr is the refractive index of the convex lens possessed by the subsequent group (GR). ΔPgFpLgr is the anomalous dispersion of the convex lens possessed by the subsequent group (GR).

13. The zoom imaging optical system according to claim 1, characterized in that, Let Lb be the lens positioned closest to the object side, located further to the image side than the aperture stop (S) and where, at infinity, the position of the off-axis principal ray incident on the object side of the lens surface is higher than the position of the on-axis edge ray incident on that lens surface. From Lb on the image side, one or more concave lenses satisfying the following condition are arranged. (13) ΔPgFnLbr>0.009 ΔPgFnLbr is the anomalous dispersion of a concave lens positioned on the image side, starting from the lens (Lb).

14. The zoom imaging optical system according to claim 1, characterized in that, Let Lb be the lens positioned closest to the object side, located on the image side of the lens (Lb) and where, at infinity, the position of the off-axis principal ray incident on the object side of the lens surface is higher than the position of the on-axis edge ray incident on the lens surface. One or more concave lenses satisfying the following condition are arranged on the image side starting from Lb. (14) vdnLbr×ΔPgFnLbr>0.8 vdnLbr is the Abbe number of a concave lens positioned on the image side, starting from the lens (Lb). ΔPgFnLbr is the anomalous dispersion of a concave lens positioned on the image side, starting from the lens (Lb).

15. The zoom imaging optical system according to claim 1, characterized in that, The subsequent group (GR) has one or more concave lenses that satisfy the following condition. (15) vdnLgr×ΔPgFnLgr>0.8 vdnLgr is the Abbe number of the concave lens possessed by the subsequent group (GR). ΔPgFnLgr is the anomalous dispersion of the concave lens possessed by the subsequent group (GR).

16. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (16) 4.5 < fT / BFT < 130 fT is the focal length of the entire system when looking at the far end at infinity. BFT is the length of the optical axis from the lens surface closest to the image to the image surface when looking at the far end at infinity.

17. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (17) 4.0 < LiT / BFT < 35.0 LiT is the length of the optical axis from the lens surface closest to the object to the image plane when viewed at infinity. BFT is the length of the optical axis from the lens surface closest to the image to the image surface when looking at the far end at infinity.

18. The zoom imaging optical system according to claim 1, characterized in that, All convex lenses constituting the first front lens group (GF1) satisfy the following condition: (18) ΔPgFpGF1>0.000 ΔPgFpGF1 is the anomalous dispersion of the convex lens in the first front lens group (GF1).

19. The zoom imaging optical system according to claim 1, characterized in that, All convex lenses constituting the first front lens group (GF1) satisfy the following condition: (19) ndpGF1 < 1.68 ndpGF1 is the refractive index of the convex lens of the first front lens group (GF1).

20. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (20) -75.0 < fT / fF2 < -5.0 fT is the focal length of the entire system when looking at the far end at infinity. fF2 is the focal length of the second front lens group (GF2) at infinity.

21. The zoom imaging optical system according to claim 1, characterized in that, The following conditions must be met. (21) -7.0 < fF1 / fF2 < -2.0 fF1 is the focal length of the first front lens group (GF1) when viewed at infinity. fF2 is the focal length of the second front lens group (GF2) at infinity.

22. The zoom imaging optical system according to claim 2, characterized in that, The following conditions must be met. (22)0.20<ΦG2FfT / ΦS1T<0.60 ΦG2FfT is the diameter of the on-axis edge ray on the surface closest to the object in the second front lens group (GF2) when viewing at infinity. ΦS1T is the diameter of the ray from the upper edge of the plane closest to the object when looking at the farthest point at infinity.

23. The zoom imaging optical system according to claim 1, characterized in that, In the case where the first front lens group (GF1) includes two lens groups, the image-side lens group moves toward the object side when zooming from the wide-angle end to the telephoto end.

24. The zoom imaging optical system according to claim 1, characterized in that, When the first front lens group (GF1) includes two lens groups, when zooming from the wide-angle end to the telephoto end, the distance between the image-side lens group and the first lens group (G1) disposed on the object side decreases, and the distance between the image-side lens group and the second front lens group (GF2) disposed on the image side increases.

25. The zoom imaging optical system according to claim 1, characterized in that, At least one of the lens groups constituting the intermediate group (GM) moves along the optical axis when focusing from an object at infinity to a closer object.

26. The zoom imaging optical system according to claim 1, characterized in that, It does not have diffractive optical elements.

27. The zoom imaging optical system according to claim 1, characterized in that, All the lens groups that make up the second front lens group (GF2) move toward the image side when zooming from the wide-angle end to the telephoto end.

28. The zoom imaging optical system according to claim 1, characterized in that, The subsequent group (GR) is fixed relative to the image plane when zooming from the wide-angle end to the telephoto end.

Images