Inverted telephoto type lens system

Claim 2

An inverted telephoto lens system of a 5-component, 5-element type, comprising from the object to the image side: a first component consisting of a negative meniscus single lens element convex to the object side; a second component consisting of a biconvex single lens element; a third component consisting of a biconcave single lens element; a fourth component consisting of a positive meniscus single lens element convex to the image side; and a fifth component consisting of a positive single lens element, wherein the lens system fulfills the following conditions: ______________________________________ N.sub.1 > 1.69 0.72(d.sub.6 + d.sub.7 + d.sub.8 + d.sub.9) < d.sub.5 < 2.2(d.sub.6 + d.sub.7 + d.sub.8 + d.sub.9) 0.14 f < d.sub.5 < 0.3 f 0.26 f < d.sub.4 < 0.43 f 0.12 f < d.sub.3 < 0.4 f ______________________________________ wherein: N 1 represents the refractive index of the material of the first component; d i represents the i-th axial distance counted from the object side; and f represents the focal length of the whole lens system.

Claim 3

The invention of claim 1, wherein the lens system further fulfills the following condition: 1.51f<f.sub.2 +|f.sub.3 |<2.2f wherein: f represents the focal length of the whole lens system; f 2 represents the focal length of the second component, and f 3 represents the focal length of the third component.

Claim 4

The invention of claim 2, wherein the lens system further fulfills the following conditions: 0.92f<r.sub.3 <2.0f 1.71f<-r.sub.4 <4.0f wherein: f represents the focal length of the whole lens system; and r 3 , r 4 represents the radii of curvature of the third and fourth surface numbered from the object side, respectively.

Claim 5

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 127.68 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 155.59 d.sub.1 5.99 N.sub.1 1.78831 ν.sub.1 47.32 r.sub.2 64.39 d.sub.2 76.21 r.sub.3 108.09 d.sub.3 28.05 N.sub.2 1.80500 ν.sub.2 44.53. r.sub.4 -220.00 d.sub.4 29.02 r.sub.5 -61.66 d.sub.5 15.51 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 214.66 d.sub.6 2.85 r.sub.7 -83.61 d.sub.7 7.43 N.sub.4 1.77250 ν.sub.4 49.77 r.sub.8 -67.86 d.sub.8 0.30 r.sub.9 -1780.44 d.sub.9 7.42 N.sub.5 1.69680 ν.sub.5 56.47 r.sub.10 -110.34 ______________________________________

Claim 6

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 127.68 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 155.59 d.sub.1 5.99 N.sub.1 1.78831 ν.sub.1 47.32 r.sub.2 64.39 d.sub.2 76.21 r.sub.3 108.09 d.sub.3 28.05 N.sub.2 1.80500 ν.sub.2 44.53. r.sub.4 -220.00 d.sub.4 29.02 r.sub.5 -61.66 d.sub.5 15.51 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 214.66 d.sub.6 2.85 r.sub.7 -83.61 d.sub.7 7.43 N.sub.4 1.77250 ν.sub.4 49.77 r.sub.8 -67.86 d.sub.8 0.30 r.sub.9 -1780.44 d.sub.9 7.42 N.sub.5 1.69680 ν.sub.5 56.47 r.sub.10 -110.34 ______________________________________

Claim 7

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 127.75 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 158.04 d.sub.1 5.89 N.sub.1 1.69680 ν.sub.1 55.52 r.sub.2 59.26 d.sub.2 55.55 r.sub.3 139.34 d.sub.3 17.28 N.sub.2 1.81100 ν.sub.2 44.86 r.sub.4 -233.02 d.sub.4 39.89 r.sub.5 -73.88 d.sub.5 15.81 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 265.81 d.sub.6 2.80 r.sub.7 -252.01 d.sub.7 7.51 N.sub.4 1.77250 ν.sub.4 49.77 r.sub.8 -73.90 d.sub.8 0.30 r.sub.9 724.23 d.sub.9 7.86 N.sub.5 1.75450 ν.sub.5 51.57 r.sub.10 -114.90 ______________________________________

Claim 8

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 127.75 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 158.04 d.sub.1 5.89 N.sub.1 1.69680 ν.sub.1 55.52 r.sub.2 59.26 d.sub.2 55.55 r.sub.3 139.34 d.sub.3 17.28 N.sub.2 1.81100 ν.sub.2 44.86 r.sub.4 -233.02 d.sub.4 39.89 r.sub.5 -73.88 d.sub.5 15.81 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 265.81 d.sub.6 2.80 r.sub.7 -252.01 d.sub.7 7.51 N.sub.4 1.77250 ν.sub.4 49.77 r.sub.8 -73.90 d.sub.8 0.30 r.sub.9 724.23 d.sub.9 7.86 N.sub.5 1.75450 ν.sub.5 51.57 r.sub.10 -114.90 ______________________________________

Claim 9

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 129.07 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 158.67 d.sub.1 6.11 N.sub.1 1.82050 ν.sub.1 43.00 r.sub.2 54.80 d.sub.2 42.30 r.sub.3 120.47 d.sub.3 38.00 N.sub.2 1.87800 ν.sub.2 38.14 r.sub.4 -172.17 d.sub.4 29.65 r.sub.5 -70.83 d.sub.5 15.81 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 198.71 d.sub.6 3.10 r.sub.7 -265.57 d.sub.7 7.00 N.sub.4 1.72900 ν.sub.4 53.48 r.sub.8 -75.64 d.sub.8 0.30 r.sub.9 4152.30 d.sub.9 8.49 N.sub.5 1.72000 ν.sub.5 54.71 r.sub.10 -91.58 ______________________________________

Claim 10

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 129.07 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 158.67 d.sub.1 6.11 N.sub.1 1.82050 ν.sub.1 43.00 r.sub.2 54.80 d.sub.2 42.30 r.sub.3 120.47 d.sub.3 38.00 N.sub.2 1.87800 ν.sub.2 38.14 r.sub.4 -172.17 d.sub.4 29.65 r.sub.5 -70.83 d.sub.5 15.81 N.sub.3 1.75000 ν.sub.3 25.14 r.sub.6 198.71 d.sub.6 3.10 r.sub.7 -265.57 d.sub.7 7.00 N.sub.4 1.72900 ν.sub.4 53.48 r.sub.8 -75.64 d.sub.8 0.30 r.sub.9 4152.30 d.sub.9 8.49 N.sub.5 1.72000 ν.sub.5 54.71 r.sub.10 -91.58 ______________________________________

Claim 11

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 128.01 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 138.10 d.sub.1 6.00 N.sub.1 1.77250 ν.sub.1 49.77 r.sub.2 70.41 d.sub.2 105.01 r.sub.3 109.06 d.sub.3 11.69 N.sub.2 1.85000 ν.sub.2 40.51 r.sub.4 -301.43 d.sub.4 28.12 r.sub.5 -62.93 d.sub.5 15.91 N.sub.3 1.80518 ν.sub.3 25.43 r.sub.6 184.62 d.sub.6 2.00 r.sub.7 -597.88 d.sub.7 7.41 N.sub.4 1.80100 ν.sub.4 46.54 r.sub.8 -70.68 d.sub.8 0.30 r.sub.9 -217.62 d.sub.9 6.97 N.sub.5 1.77250 ν.sub.5 49.77 r.sub.10 -88.68 ______________________________________

Claim 12

An inverted telephoto lens system comprising the following arrangement and construction: ______________________________________ f = 100 F.sub.No. 2.8 2ω = 76° L.B. = 128.01 Radius of Axial Refractive Abbe Curvature Distance Index Number ______________________________________ r.sub.1 138.10 d.sub.1 6.00 N.sub.1 1.77250 ν.sub.1 49.77 r.sub.2 70.41 d.sub.2 105.01 r.sub.3 109.06 d.sub.3 11.69 N.sub.2 1.85000 ν.sub.2 40.51 r.sub.4 -301.43 d.sub.4 28.12 r.sub.5 -62.93 d.sub.5 15.91 N.sub.3 1.80518 ν.sub.3 25.43 r.sub.6 184.62 d.sub.6 2.00 r.sub.7 -597.88 d.sub.7 7.41 N.sub.4 1.80100 ν.sub.4 46.54 r.sub.8 -70.68 d.sub.8 0.30 r.sub.9 -217.62 d.sub.9 6.97 N.sub.5 1.77250 ν.sub.5 49.77 r.sub.10 -88.68 ______________________________________