Miniature and large aperture retrofocus wide-angle photographic lens

Claim 2

A wide angle photographic lens system comprising at least five lens groups positioned in order from the object to the image side of the lens system, the first lens group being a positive lens consisting of a positive meniscus lens element convex to the object, the second lens group being a negative lens and consisting of two negative meniscus lens elements, the third lens group being a positive lens and consisting of in the order mentioned a thick positive lens element joined to a negative lens element, the fourth lens group being a positive lens and comprising at least a positive lens element and a negative lens element, and the fifth lens group being a positive lens and comprising at least two positive lens elements wherein the first positive lens element of said fifth group consists of a negative lens joined to a positive lens, and a diaphragm being interposed between said third lens group and said fourth lens group.

Claim 3

A wide angle photographic lens according to claim 1, further comprising a filter interposed between said second lens group and said third lens group.

Claim 4

A wide angle photographic lens according to claim 1, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractive index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 94.5° Refractive Lens Index N/ Radius of Thickness Abbe Lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 282.073 d.sub.1 = 38.390 N.sub.1 /ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 857.893 d.sub.2 = 0.488 2 r.sub.3 = 141.907 d.sub.3 = 5.878 N.sub.2 /ν.sub.2 = 1.64000/60.2 2 r.sub.4 = 68.712 d.sub.4 = 41.707 3 r.sub.5 = 166.702 d.sub.5 = 5.854 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 67.168 d.sub.6 = 24.878 filter ∞ 7.317 1.51633/64.1 filter ∞ 2.537 4 r.sub.7 = 484.917 d.sub.7 = 76.927 N.sub.4 /ν.sub.4 = 1.80518/25.4 4 & 5 r.sub.8 = -250.893 d.sub.8 = 6.244 N.sub.5 /ν.sub.5 = 1.71700/47.9 5 r.sub.9 = -574.546 d.sub.9 = 13.658 6 r.sub.10 = 551.585 d.sub.10 = 47.659 N.sub.6 /ν.sub.6 = 1.73400/51.5 6 r.sub.11 = -150.249 d.sub.11 = 0.390 7 r.sub.12 = -384.688 d.sub.12 = N.sub.7 /ν.sub.7 = 1.84666/23.9 7 r.sub.13 = 198.849 d.sub.13 = 17.268 8 r.sub.14 =-1536.502 d.sub.14 = N.sub.8 /ν.sub.8 = 1.84666/23.9 8 & 9 r.sub.15 = 400.410 d.sub.15 = 32.780 N.sub.9 /ν.sub.9 = 1.69680/55.5 9 r.sub.16 = -157.551 d.sub.16 = 0.488 10 r.sub.17 = 322.741 d.sub.17 = 26.366 N.sub.10 /ν.sub.10 = 1.77250/49.7 10 r.sub.18 = -470.980 back focal length = 179.000 F.sub.A.B = -116.836 F.sub.A.B.C.D = -237.079 d.sub.C.D = 150.732 Sum of Petzval = 0.090 All linear dimensions are given in millimeters. ______________________________________ pg,20

Claim 5

A wide angle photographic lens system comprising at least five lens groups positioned in order from the object to the image side of the lens system, the first lens group being a positive lens consisting of a positive meniscus lens element convex to the object, the second lens group being a negative lens and consisting of two negative meniscus lens elements, the third lens group being a positive lens and consisting of in the order mentioned a negative lens element joined to a thick positive lens element, the fourth lens group being a positive lens and comprising at least a positive lens element and a negative lens element, and the fifth lens group being a positive lens and comprising at least two positive lens elements wherein the first positive lens element of said fifth lens group consists of a negative lens element joined to a positive lens element, and a diaphragm being interposed between said third lens group and said fourth lens group.

Claim 6

A wide angle photographic lens system comprising at least five lens groups positioned in order from the object to the image side of the lens system, the first lens group being a positive lens consisting of a positive meniscus lens element convex to the object, the second lens group being a negative lens and consisting of two negative meniscus lens elements, the third lens group being a positive lens and consisting of in the order mentioned a negative lens element joined to a thick positive lens element, the fourth lens group being a positive lens and comprising at least a positive lens element and a negative lens element, and the fifth lens group being a positive lens and comprising at least two positive lens elements wherein the first positive lens element of said fifth lens group consists of a negative lens element joined to a positive lens element, and a diaphragm being interposed between said third lens group and said fourth lens group.

Claim 7

A wide angle photographic lens according to claim 4 further comprising a filter interposed between said second lens group and said third lens group.

Claim 8

A wide angle photographic lens according to claim 4, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractive index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 95° Refractive Lens Index N/ Radius of Thickness Abbe lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 290.595 d.sub.1 = 41.024 N.sub.1 /ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 867.896 d.sub.2 = 0.488 2 r.sub.3 = 146.068 d.sub.3 = 5.854 N.sub.2 /ν.sub.2 = 1.64000/60.2 2 r.sub.4 = 70.405 d.sub.4 = 43.805 3 r.sub.5 = 164.917 d.sub.5 = 5.854 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 66.983 filter ∞ 7.317 1.51633/64.1 filter ∞ 2.439 4 r.sub.7 = 497.780 d.sub.7 = 9.756 N.sub.4 /ν.sub.4 = 1.72000/50.2 4 & 5 r.sub.8 = 243.902 d.sub.8 = 70.732 N.sub. 5 /ν.sub.5 = 1.80518/25.4 5 r.sub.9 = -557.507 d.sub.9 = 13.659 6 r.sub.10 = 558.663 d.sub.10 = 49.854 N.sub.6 /ν.sub.6 = 1.72916/54.7 6 r.sub.11 = -146.740 d.sub.11 = 0.390 7 r.sub.12 = -369.015 d.sub.12 = N.sub.7 /ν.sub.7 = 1.84666/23.9 7 r.sub.13 = 194.379 d.sub.13 = 17.024 8 r.sub.14 =-1876.346 d.sub.14 = N.sub.8 /ν.sub.8 = 1.84666/23.9 8 & 9 r.sub.15 = 539.834 d.sub.15 = 29.512 N.sub.9 /ν.sub.9 = 1.69680/55.5 9 r.sub.16 = -166.635 d.sub.16 = 0.488 10 r.sub.17 = 340.673 d.sub.17 = 26.439 N.sub.10 /ν.sub.10 = 1.77250/49.7 10 r.sub.18 = -375.661 back focal length = 178.161 F.sub.A.B = - 117.288 F.sub.A.B.C.D = - 223.214 d.sub.C.D = 151.220 Sum of petzval = 0.097 All linear dimensions are given in millimeters. ______________________________________

Claim 9

A wide angle photographic lens system comprising at least five lens groups positioned in order from the object to the image side of the lens system, the first lens group being a positive lens consisting of a positive meniscus lens convex to the object, the second lens group being a negative lens and consisting of three negative meniscus lens elements each convex to the object, the third lens group being a positive lens and comprising at least a thick positive lens element, the fourth lens group being a positive lens and comprising at least a positive lens element and a negative lens element, and the fifth lens group being a positive lens and comprising at least two positive lens elements, and a diaphragm being interposed between said third lens group and said fourth lens group.

Claim 10

A wide angle photographic lens system comprising at least five lens groups positioned in order from the object to the image side of the lens system, the first lens group being a positive lens consisting of a positive meniscus lens convex to the object, the second lens group being a negative lens and consisting of three negative meniscus lens elements each convex to the object, the third lens group being a positive lens and comprising at least a thick positive lens element, the fourth lens group being a positive lens and comprising at least a positive lens element and a negative lens element, and the fifth lens group being a positive lens and comprising at least two positive lens elements, and a diaphragm being interposed between said third lens group and said fourth lens group.

Claim 11

A wide angle photographic lens according to claim 5 further comprising a filter interposed between said second lens group and said third lens group.

Claim 12

A wide angle photographic lens according to claim 7, wherein said third lens group consists of in the order mentioned a negative lens element joined to said thick positive lens element.

Claim 13

A wide angle photographic lens according to claim 9, wherein the first positive lens element of said fifth lens group consists of a negative lens joined to a positive lens.

Claim 14

A wide angle photographic lens according to claim 10, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractice index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 95° Refractive Lens Index N/ Radius of Thickness Abbe lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 349.515 d.sub.1 = 33.883 N.sub.1 /ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 1026.524 d.sub.2 = 0.485 2 r.sub.3 = 134.820 d.sub.3 = 5.825 N.sub.2 /ν.sub.2 = 1.61800/63.4 2 r.sub.4 = 76.010 d.sub.4 = 36.650 3 r.sub.5 = 122.500 d.sub.5 = 5.825 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 77.874 d.sub.6 = 15.631 4 r.sub.7 = 160.796 d.sub.7 = 5.874 N.sub.4 /ν.sub.4 = 1.61800/63.4 4 r.sub.8 = 79.277 d.sub.8 = 19.417 filter ∞ 7.282 1.51633/64.1 filter ∞ 2.427 5 r.sub.9 = 358.447 d.sub.9 = 10.874 N.sub.5 /ν.sub.5 = 1.69680/55.5 5 & 6 r.sub.10 = 277.141 d.sub.10 = 78.350 N.sub.6 /ν.sub.6 = 1.80518/25.4 6 r.sub.11 = -611.117 d.sub.11 = 13.592 7 r.sub.12 = 614.078 d.sub.12 = 56.699 N.sub.7 /ν.sub.7 = 1.72000/50.2 7 r.sub.13 = -152.981 d.sub.13 = 0.388 8 r.sub.14 = -465.534 d.sub.14 = N.sub.8 /ν.sub.8 = 1.84666/23.9 8 r.sub.15 = 198.544 d.sub.15 = 15.243 9 r.sub.16 ∞ d.sub.16 = N.sub.9 /ν.sub.9 = 1.84666/23.9 9 & 10 r.sub.17 = 36.976 d.sub.17 = 31.893 N.sub.10 /ν.sub.10 = 1.61800/63.4 10 r.sub.18 = - 162.636 d.sub.18 = 0.485 11 r.sub.19 = 291.641 d.sub.19 = 29.612 N.sub.11 /ν.sub.11 = 1.75700/47.9 11 r.sub.20 = -449.447 Back focal length = 181.155 F.sub.A.B = - 108.554 F.sub.A.B.C.D = - 232.072 d.sub.C.D = 165.728 Sum of Petzval = 0.102 All linear dimensions are given in millimeters. ______________________________________

Claim 15

A wide angle photographic lens according to claim 9, wherein the second positive lens element of said fifth lens group consists of a negative lens joined to a positive lens.

Claim 16

A wide angle photographic lens according to claim 12, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractice index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 94.5° Refractive Lens Index N/ Radius of Thickness Abbe Lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 427.020 d.sub.1 = 34.858 N.sub.1 /ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 1503.451 d.sub.2 = 0.485 2 r.sub.3 = 139.474 d.sub.3 = 7.069 N.sub.2 /ν.sub.2 = 1.62041/60.3 2 r.sub.4 = 77.004 d.sub.4 = 29.367 3 r.sub.5 = 129.595 d.sub.5 = 5.908 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 81.507 d.sub.6 = 15.705 4 r.sub.7 = 148.761 d.sub.7 = 5.370 N.sub.4 /ν.sub.4 = 1.62041/60.3 4 r.sub.8 = 75.801 d.sub.8 = 23.062 filter ∞ 7.282 1.51633/64.1 filter ∞ 1.876 5 r.sub.9 = 357.740 d.sub.9 = 10.712 N.sub.5 /ν.sub.5 = 1.69350/53.3 5 & 6 r.sub.10 = 382.976 d.sub.10 = 79.048 N.sub.6 /ν.sub.6 = 1.80518/25.4 6 r.sub.11 = -713.896 d.sub.11 = 13.592 7 r.sub.12 = 628.800 d.sub.12 = 56.899 N.sub.7 /ν.sub.7 = 1.72000/50.2 7 r.sub.13 = -160.170 d.sub.13 = 0.388 8 r.sub.14 = -723.035 d.sub.14 = N.sub.8 /ν.sub.8 = 1.84666/23.9 8 r.sub.15 = 189.463 d.sub.15 = 16.275 9 r.sub.16 = 1358.156 d.sub.16 = 47.573 N.sub.9 /ν.sub.9 = 1.75700/47.9 9 r.sub.17 = -197.235 d.sub.17 = 0.485 10 r.sub.18 = 285.591 d.sub.18 = N.sub. 10 /ν.sub.10 = 1.84666/23.9 10 & 11 r.sub.19 = 180.289 d.sub.19 = 33.113 N.sub.11 /ν.sub.11 = 1.61800/60.3 11 r.sub.20 = -450.043 Back focal length = 178.650 F.sub.A.B = - 106.564 F.sub.A.B.C.D = - 223.914 d.sub.C.D = 166.458 Sum of petzval = 0.082 All linear dimensions are given in millimeters. ______________________________________

Claim 17

A wide angle photographic lens according to claim 7, wherein said third lens group consists only of said thick positive lens element.

Claim 18

A wide angle photographic lens according to claim 14, wherein the second positive lens element of said fifth lens group consists of a negative lens joined to a positive lens.

Claim 19

A wide angle photographic lens according to claim 15, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractive index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 94.5° Refractive Lens Index N/ Radius of Thickness Abbe Lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 427.020 d.sub.1 = 34.858 N.sub.1 /ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 1503.451 d.sub.2 = 0.485 2 r.sub.3 = 139.474 d.sub.3 = 7.069 N.sub.2 /ν.sub.2 = 1.62041/60.3 2 r.sub.4 = 77.004 d.sub.4 = 29.367 3 r.sub.5 = 129.595 d.sub.5 = 5.908 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 81.507 d.sub.6 = 15.705 4 r.sub.7 = 148.761 d.sub.7 = 5.370 N.sub.4 /ν.sub.4 = 1.62041/60.3 4 r.sub.8 = 75.801 d.sub.8 = 23.062 filter ∞ 7.282 1.51633/64.1 filter ∞ 1.876 5 r.sub.9 = 357.740 d.sub.9 =89.760 N.sub.5 /ν.sub.5 = 1.78472/25.7 5 r.sub.10 = -674.300 d.sub.10 = 13.592 6 r.sub.11 = 628.800 d.sub.11 = 56.899 N.sub.6 /ν.sub.6 = 1.72000/50.2 6 r.sub.12 = -160.350 d.sub.12 = 0.388 7 r.sub.13 = -723.035 d.sub.13 = N.sub.7 /ν.sub.7 = 1.84666/23.9 7 r.sub.14 = 189.677 d.sub.14 = 16.275 8 r.sub.15 = 1358.156 d.sub.15 = 47.573 N.sub.8 /ν.sub.8 = 1.75700/47.9 8 r.sub.16 = -197.417 d.sub.16 = 0.485 9 r.sub.17 = 285.591 d.sub.17 = N.sub.9 /ν.sub.9 = 1.84666/23.9 9 & 10 r.sub.18 = 180.289 d.sub.18 = 33.113 N.sub.10 /ν.sub. 10 = 1.61800/60.3 10 r.sub.19 = -450.927 Back focal length = 178.806 F.sub.A.B = - 106.564 F.sub.A.B.C.D = - 223.914 d.sub.C.D = 166.458 Sum of Petzval = 0.084 All linear dimensions are given in millimeters. ______________________________________

Claim 20

A wide angle photographic lens according to claim 14, wherein the first positive lens of said fifth lens group consists of a negative lens element joined to a positive lens.

Claim 21

A wide angle photographic lens according to claim 17, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractive index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 95° Refractive Lens Index N/ Radius of Thickness Abbe Lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 349.515 d.sub.1 = 33.883 N.sub.1 /ν.sub.1 = 1.62041/60.3 1 r.sub.2 = 1019.316 d.sub.2 = 0.485 2 r.sub.3 = 134.820 d.sub.3 = 5.825 N.sub.2 /ν.sub.2 = 1.61800/63.4 2 r.sub.4 = 76.000 d.sub.4 = 36.650 3 r.sub.5 = 122.578 d.sub.5 = 5.825 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 77.949 d.sub.6 = 15.631 4 r.sub.7 = 160.757 d.sub.7 = 5.874 N.sub.4 /ν.sub.4 = 1.61800/63.4 4 r.sub.8 = 79.284 d.sub.8 = 19.417 filter ∞ 7.282 1.51633/64.1 filter ∞ 2.427 5 r.sub.9 = 351.942 d.sub.9 = 89.223 N.sub.5 /ν.sub.5 = 1.80518/25.4 5 r.sub.10 = -589.338 d.sub.10 = 13.592 6 r.sub.11 = 613.859 d.sub.11 = 56.699 N.sub.6 /ν.sub.6 = 1.71700/47.9 6 r.sub.12 = -152.055 d.sub.12 = 0.388 7 r.sub.13 = -465.534 d.sub.13 = N.sub.7 /ν.sub.7 = 1.84666/23.9 7 r.sub.14 = 198.267 d.sub.14 = 15.243 8 r.sub.15 = ∞ d.sub.15 = N.sub.8 /ν.sub.8 = 1.84666/23.9 8 & 9 r.sub.16 = 387.102 d.sub.16 = 31.893 N.sub.9 /ν.sub.9 = 1.61800/63.4 9 r.sub.17 = -162.626 d.sub.17 = 0.485 10 r.sub.18 = 291.748 d.sub.18 = N.sub.10 /ν.sub.10 = 1.75700/47.9 10 r.sub.19 = -447.530 Back focal length = 180.966 F.sub.A.B = - 108.554 F.sub.A.B.C.D = -232.072 d.sub.C.D = 165.727 Sum of Petzval = 0.105 All linear dimensions are given in millimeters. ______________________________________

Claim 22

A wide angle photographic lens according to claim 14, wherein the fifth lens group consists of only said two positive lens elements.

Claim 23

A wide angle photographic lens according to claim 19, wherein the radii of curvature r 1 to r 18 , the lens thickness or distance d 1 to d 17 , and the ratio of the refractive index to the Abbe number N 1 /ν 1 to N 10 /ν 10 being substantially as given in the following table: ______________________________________ Aperture ratio 1 : 1.4 Angular field 94° Refractive Lens Index N/ Radius of Thickness Abbe Lens # Curvature r or Distance d No. ν ______________________________________ 1 r.sub.1 = 408.859 d.sub.1 = 35.151 N.sub.1 ν.sub.1 = 1.61800/63.4 1 r.sub.2 = 1326.694 d.sub.2 = 0.485 2 r.sub.3 = 142.718 d.sub.3 = 5.828 N.sub.2 /ν.sub.2 = 1.61800/63.4 2 r.sub.4 = 78.421 d.sub.4 = 32.426 3 r.sub.5 = 128.290 d.sub.5 = 5.865 N.sub.3 /ν.sub.3 = 1.61800/63.4 3 r.sub.6 = 81.441 d.sub.6 = 18.980 4 r.sub.7 = 161.794 d.sub.7 = 5.842 N.sub.4 /ν.sub.4 = 1.61800/63.4 4 r.sub.8 = 78.193 d.sub.8 = 22.788 filter ∞ 7.282 1.51633/64.1 filter ∞ 0.485 5 r.sub.9 = 325.243 d.sub.9 = 88.180 N.sub.5 /ν.sub.5 = 1.80518/25.4 5 r.sub.10 = -381.074 d.sub.10 = 13.592 6 r.sub.11 = 807.840 d.sub.11 = 60.410 N.sub.6 /ν.sub.6 = 1.72916/54.7 6 r.sub.12 = -156.014 d.sub.12 = 0.388 7 r.sub.13 = -497.315 d.sub.13 = N.sub.7 /ν.sub.7 = 1.92286/20.9 7 r.sub.14 = 194.265 d.sub.14 = 15.638 8 r.sub.15 =-4152.361 d.sub.15 = 34.213 N.sub.8 /ν.sub.8 = 1.72916/54.7 8 r.sub.16 = -187.957 d.sub.16 = 0.485 9 r.sub.17 = 336.916 d.sub.17 = 22.550 N.sub.9 /ν.sub.9 = 1.72916/54.7 9 r.sub.18 = -403.796 Back focal length = 179.427 F.sub.A.B = - 106.564 d.sub.C.D = 170.231 Sum of Petzval = 0.099 All linear dimensions are given in millimeters. F.sub.A.B.C.D = - 223.914 ______________________________________