Bright and compact optical-compensation type zoom lens system

Claim 2

A bright and compact optical-compensation type zoom lens system comprising a first lens group I having positive refractive power, a second lens group II having negative refractive power, a third lens group III having positive refractive power, and a fourth lens group IV having positive refractive power, said zoom lens system being arranged to carry out zooming by keeping said second lens group II and said fourth lens group IV fixed and integrally moving said first lens group I and said third lens group III, said first lens group I comprising a cemented doublet consisting of a positive lens element and negative lens element, said second lens group II comprising at least one positive lens element and at least one negative lens element and comprising a cemented doublet having the surface on the object side thereof concave toward the object side, said third lens group III comprising a cemented doublet consisting of a positive lens element and negative lens element, said fourth lens group IV comprising at least one positive lens component and at least one negative lens component, said zoom lens system satisfying the following conditions (1) through (6): 0.5F.sub.W <|F.sub.II |<1.0F.sub.W ( 1) 0.6F.sub.W <F.sub.III <1.5F.sub.W ( 2) 0.6F.sub.W <r.sub.I-1 <2.0F.sub.W ( 3) 0.4F.sub.W <|r.sub.II |<1.2F.sub.W ( 4) ΔN.sub.II +ΔN.sub.III ≦0.4 (5) Δν.sub.I >15 (6) wherein reference symbol F W represents the shortest focal length of the lens system as a whole, reference symbol F II represents the focal length of the second lens group II, reference symbol F III represents the focal length of the third lens group III, reference symbol r I-1 represents the radius of curvature of the surface on the object side of the first lens group I, reference symbol r II represents the radius of curvature of the surface on the object side of the cemented doublet constituting the second lens group II, reference symbol ΔN II represents the difference between the mean value N' II of refractive indices of positive lenses constituting the second lens group II and mean value N" II of refractive indices of negative lenses constituting the second lens group II, reference symbol ΔN III represents the difference between the mean value N" III of refractive indices of negative lenses constituting the third lens group III and mean value N' III of refractive indices of positive lenses constituting the third lens group III, and reference symbol Δν I represents the value obtained by subtracting the Abbe's number ν" I of the negative lens constituting the first lens group I from the Abbe's number ν' I of the positive lens constituting the first lens group I.

Claim 3

A bright and compact optical-compensation type zoom lens system according to claim 1 further satisfying the following condition (7): 0.6<|r.sub.III-1 /r.sub.III-2 |<2.5 (7) wherein reference symbols r III-1 and r III-2 respectively represent radii of curvature of the surface on the object side and cemented surface of the cemented doublet constituting the third lens group III.

Claim 4

A bright and compact optical-compensation type zoom lens system according to claim 2 further satisfying the following condition (8): |r.sub.I-2 |>0.4F.sub.W ( 8) wherein reference symbol r I-2 represents the radius of curvature of the cemented surface of the cemented doublet constituting the first lens group I.

Claim 5

A bright and compact optical-compensation type zoom lens system according to claim 3 further satisfying the following conditions (9) and (10): N.sub.IV >1.5 (9) N.sub.I >1.5 (10) wherein reference symbol N I represents the mean value of refractive indices of respective lenses constituting the first lens group I, and reference symbol N IV represents the mean value of refractive indices of respective lenses constituting the fourth lens group IV.

Claim 6

A bright and compact optical-compensation type zoom lens system according to claim 1, in which said first lens group I comprises a cemented doublet consisting of a positive lens element and negative lens element, said second lens group II comprises a negative lens component and a cemented doublet consisting of a negative lens element and positive lens element, said third lens group III comprises a cemented doublet consisting of a negative lens element and positive lens element, and said fourth lens group IV comprises a positive lens component, negative lens component and positive lens component.

Claim 7

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 106.068 d.sub.1 = 8.16 n.sub.1 = 1.63854 ν.sub.1 = 55.4 r.sub.2 = -89.917 d.sub.2 = 2.56 n.sub.2 = 1.6398 ν.sub.2 = 34.5 r.sub.3 = 430.595 d.sub.3 = D.sub.1 (variable) r.sub.4 = 630.592 d.sub.4 = 1.58 n.sub.3 = 1.47069 ν.sub.3 = 67.4 r.sub.5 = 53.66 d.sub.5 = 5.28 r.sub.6 = -51.723 d.sub.6 = 1.49 n.sub.4 = 1.56873 ν.sub.4 = 63.2 r.sub.7 = 57.981 d.sub.7 = 6.4 n.sub.5 = 1.64769 ν.sub.5 = 33.8 r.sub.8 = -167.369 d.sub.8 = D.sub.2 (variable) r.sub.9 = 97.414 d.sub.9 = 1.51 n.sub.6 = 1.80518 ν.sub.6 = 25.4 r.sub.10 = 42.127 d.sub.10 = 7.99 n.sub.7 = 1.64328 ν.sub.7 = 47.9 r.sub.11 = -90.745 d.sub.11 = D.sub.3 (variable) r.sub.12 = 53.361 d.sub.12 = 3.89 n.sub.8 = 1.617 ν.sub.8 = 62.8 r.sub.13 = 2063.483 d.sub.13 = 5.93 r.sub.14 = -72.391 d.sub.14 = 2.09 n.sub.9 = 1.56732 ν.sub.9 = 42.8 r.sub.15 = 59.667 d.sub.15 = 7.4 r.sub.16 = -75.87 d.sub.16 = 5.74 n.sub.10 = 1.6516 ν.sub.10 = 58.7 r.sub.17 = -43.246 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.57 5.616 37.409 6.759 147.62 26.691 16.335 27.833 193 41.826 1.199 42.968 F.sub.II = -0.714F.sub.W F.sub.III = 0.86F.sub.W r.sub.I-1 = 1.034F.sub.W |r.sub.II | = 0.504F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.28988 Δν.sub.I = 20.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 8

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 105.22 d.sub.1 = 8.27 n.sub.1 = 1.6935 ν.sub.1 = 53.2 r.sub.2 = -116.871 d.sub.2 = 2.56 n.sub.2 = 1.6727 ν.sub.2 = 32.1 r.sub.3 = 294.901 d.sub.3 = D.sub.1 (variable) r.sub.4 = 459.551 d.sub.4 = 1.58 n.sub.3 = 1.47069 ν.sub.3 = 67.4 r.sub.5 = 55.4 d.sub.5 = 5.29 r.sub.6 = -49.782 d.sub.6 = 1.49 n.sub.4 = 1.56873 ν.sub.4 = 63.2 r.sub.7 = 68.045 d.sub.7 = 6.33 n.sub.5 = 1.6398 ν.sub.5 = 34.5 r.sub.8 = -157.932 d.sub.8 = D.sub.2 (variable) r.sub.9 = 100.383 d.sub.9 = 1.51 n.sub.6 = 1.80518 ν.sub.6 = 25.4 r.sub.10 = 45.145 d.sub.10 = 8.13 n.sub.7 = 1.64328 ν.sub.7 = 47.9 r.sub.11 = -90.856 d.sub.11 = D.sub.3 (variable) r.sub.12 = 51.818 d.sub.12 = 4.54 n.sub.8 = 1.6935 ν.sub.8 = 53.2 r.sub.13 = 127.254 d.sub.13 = 7.1 r.sub.14 = -283.406 d.sub.14 = 2.78 n.sub.9 = 1.59551 ν.sub.9 = 39.2 r.sub.15 = 53.47 d.sub.15 = 8.59 r.sub.16 = 361.809 d.sub.16 = 6.61 n.sub.10 = 1.6935 ν.sub.10 = 53.2 r.sub.17 = -161.703 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.58 4.714 37.563 3.119 147.62 25.789 16.489 24.193 193 40.924 1.353 39.328 F.sub.II = -0.714F.sub.W F.sub.III = 0.86F.sub.W r.sub.I-1 = 1.026F.sub.W |r.sub.II | = 0.485F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.28199 Δν.sub.I = 21.1 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 9

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 83.719 d.sub.1 = 7.8 n.sub.1 = 1.60311 ν.sub.1 = 60.7 r.sub.2 = -178.01 d.sub.2 = 2.49 n.sub.2 = 1.59551 ν.sub.2 = 39.2 r.sub.3 = 213.01 d.sub.3 = D.sub.1 (variable) r.sub.4 = 127.605 d.sub.4 = 1.58 n.sub.3 = 1.47069 ν.sub.3 = 67.4 r.sub.5 = 50.027 d.sub.5 = 5.63 r.sub.6 = -52.717 d.sub.6 = 1.49 n.sub.4 = 1.56873 ν.sub.4 = 63.2 r.sub.7 = 76.081 d.sub.7 = 6.3 n.sub.5 = 1.68893 ν.sub.5 = 31.1 r.sub.8 = -516.424 d.sub.8 = D.sub.2 (variable) r.sub.9 = 95.301 d.sub.9 = 1.51 n.sub.6 = 1.80518 ν.sub.6 = 25.4 r.sub.10 = 44.296 d.sub.10 = 8.23 n.sub.7 = 1.62299 ν.sub.7 = 58.1 r.sub.11 = -86.766 d.sub.11 = D.sub.3 (variable) r.sub.12 = 45.454 d.sub.12 = 4.71 n.sub.8 = 1.72 ν.sub.8 = 46 r.sub.13 = 105.219 d.sub.13 = 9.32 r.sub.14 = -2263.939 d.sub.14 = 3.22 n.sub.9 = 1.66755 ν.sub.9 = 41.9 r.sub.15 = 43.134 d.sub.15 = 9.05 r.sub.16 = 95.423 d.sub.16 = 4.43 n.sub.10 = 1.62012 ν.sub.10 = 49.7 r.sub.17 = -2903.76 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.71 1.879 39.428 13.804 147.8 22.954 18.354 34.878 193.23 38.089 3.218 50.013 F.sub.II = -0.713F.sub.W F.sub.III = 0.859F.sub.W r.sub.I-1 = 0.815F.sub.W |r.sub.II | = 0.513F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.35141 Δν.sub.I = 21.5 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 10

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 89.93 d.sub.1 = 2.49 n.sub.1 = 1.64769 ν.sub.1 = 33.8 r.sub.2 = 47.682 d.sub.2 = 6.74 n.sub.2 = 1.6516 ν.sub.2 = 58.7 r.sub.3 = 231.179 d.sub.3 = D.sub.1 (variable) r.sub.4 = -266 d.sub.4 = 1.58 n.sub.3 = 1.51633 ν.sub.3 = 64.2 r.sub.5 = 74.861 d.sub.5 = 5.23 r.sub.6 = -51.543 d.sub.6 = 1.58 n.sub.4 = 1.691 ν.sub.4 = 54.8 r.sub.7 = 129.457 d.sub.7 = 4.88 n.sub.5 = 1.68893 ν.sub.5 = 31.1 r.sub.8 = -84.447 d.sub.8 = D.sub.2 (variable) r.sub.9 = 157.408 d.sub.9 = 1.51 n.sub.6 = 1.7847 ν.sub.6 = 26.2 r.sub.10 = 48.608 d.sub.10 = 7.36 n.sub.7 = 1.72 ν.sub.7 = 50.3 r.sub.11 = -91.938 d.sub.11 = D.sub.3 (variable) r.sub.12 = 57.692 d.sub.12 = 5.19 n.sub.8 = 1.6968 ν.sub.8 = 55.5 r.sub.13 = 171.955 d.sub.13 = 8.55 r.sub.14 = -131.619 d.sub.14 = 3.11 n.sub.9 = 1.57501 ν.sub.9 = 41.5 r.sub.15 = 68.064 d.sub.15 = 8.8 r.sub.16 = 1663.829 d.sub.16 = 5.19 n.sub.10 = 1.67 ν.sub.10 = 51.6 r.sub.17 = -124.903 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.58 6.698 36.823 14.306 147.62 27.773 15.749 35.38 193 42.908 0.613 50.515 F.sub.II = - 0.714F.sub.W F.sub.III = 0.86F.sub.W r.sub.I-1 = 0.877F.sub.W |r.sub.II | = 0.502F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.14997 Δν.sub.I = 24.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvative of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 11

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 133.067 d.sub.1 = 3.00 n.sub.1 = 1.64769 ν.sub.1 = 33.8 r.sub.2 = 65.29 d.sub.2 = 6.00 n.sub.2 = 1.6516 ν.sub.2 = 58.7 r.sub.3 = 562.205 d.sub.3 = D.sub.1 (variable) r.sub.4 = -217.465 d.sub.4 = 2.00 n.sub.3 = 1.51633 ν.sub.3 = 64.2 r.sub.5 = 105.496 d.sub.5 = 4.00 r.sub.6 = -76.869 d.sub.6 = 2.00 n.sub.4 = 1.691 ν.sub.4 = 54.8 r.sub.7 = 120.854 d.sub.7 = 4.81 n.sub.5 = 1.68893 ν.sub.5 = 31.1 r.sub.8 = -130.195 d.sub.8 = D.sub.2 (variable) r.sub.9 = 174.709 d.sub.9 = 1.92 n.sub.6 = 1.78472 ν.sub.6 = 25.7 r.sub.10 = 66.198 d.sub.10 = 8.00 n.sub.7 = 1.691 ν.sub.7 = 54.8 r.sub.11 = -115.764 d.sub.11 = D.sub.3 (variable) r.sub.12 = 34.949 d.sub.12 = 5.05 n.sub.8 = 1.63854 ν.sub.8 = 55.4 r.sub.13 = 88.396 d.sub.13 = 5.72 r.sub.14 = -336.049 d.sub.14 = 3.4 n.sub.9 = 1.56732 ν.sub.9 = 42.8 r.sub.15 = 35.326 d.sub.15 = 5.89 r.sub.16 = 267.612 d.sub.16 = 5.45 n.sub.10 = 1.62299 ν.sub.10 = 58.1 r.sub.17 = -112.548 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.69 2.6 48.162 24.166 144.97 27.831 22.931 49.397 193.4 48.533 2.229 70.099 F.sub.II = -0.905F.sub.W F.sub.III = 1.09F.sub.W r.sub.I-1 = 1.296F.sub.W |r.sub.II | = 0.749F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.17899 Δν.sub.I = 24.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 12

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 112.279 d.sub.1 = 3.00 n.sub.1 = 1.64769 ν.sub.1 = 33.8 r.sub.2 = 65.37 d.sub.2 = 6.00 n.sub.2 = 1.6516 ν.sub.2 = 58.7 r.sub.3 = 310.971 d.sub.3 = D.sub.1 (variable) r.sub.4 = -303.957 d.sub.4 = 2.00 n.sub.3 = 1.51633 ν.sub.3 = 64.2 r.sub.5 = 95.796 d.sub.5 = 4.00 r.sub.6 = -72.999 d.sub.6 = 2.00 n.sub.4 = 1.691 ν.sub.4 = 54.8 r.sub.7 = 120.852 d.sub.7 = 4.81 n.sub.5 = 1.68893 ν.sub.5 = 31.1 r.sub.8 = -123.895 d.sub.8 = D.sub.2 (variable) r.sub.9 = 173.609 d.sub.9 = 1.92 n.sub.6 = 1.78472 ν.sub.6 = 25.7 r.sub.10 = 59.603 d.sub.10 = 8.00 n.sub.7 = 1.691 ν.sub.7 = 54.8 r.sub.11 = -113.364 d.sub.11 = D.sub.3 (variable) r.sub.12 = 32.184 d.sub.12 = 5.05 n.sub.8 = 1.63854 ν.sub.8 = 55.4 r.sub.13 = 62.499 d.sub.13 = 5.72 r.sub.14 = -2741.179 d.sub.14 = 3.4 n.sub.9 = 1.56732 ν.sub.9 = 42.8 r.sub.15 = 32.061 d.sub.15 = 5.89 r.sub.16 = 87.089 d.sub.16 = 5.45 n.sub.10 = 1.61484 ν.sub.10 = 51.2 r.sub.17 = -270.876 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.69 1.255 48.139 24.332 144.97 26.486 22.908 49.563 193.4 47.188 2.206 70.265 ______________________________________ F.sub.II = -0.905F.sub.W F.sub.III = 1.09F.sub.W r.sub.I-1 = 1.093F.sub.W |r.sub.II | = 0.711F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.17899 Δν.sub.I = 24.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 13

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 132.817 d.sub.1 = 3.00 n.sub.1 = 1.64769 ν.sub.1 = 33.8 r.sub.2 = 65.29 d.sub.2 = 6.00 n.sub.2 = 1.6516 ν.sub.2 = 58.7 r.sub.3 = 557.645 d.sub.3 = D.sub.1 (variable) r.sub.4 = -229.584 d.sub.4 = 2.00 n.sub.3 = 1.56873 ν.sub.3 = 63.2 r.sub.5 = 110.963 d.sub.5 = 4.00 r.sub.6 = -73.683 d.sub.6 = 2.00 n.sub.4 = 1.755 ν.sub.4 = 52.3 r.sub.7 = 434.45 d.sub.7 = 5.00 n.sub.5 = 1.7552 ν.sub.5 = 27.5 r.sub.8 = -112.23 d.sub.8 = D.sub.2 (variable) r.sub.9 = 176.246 d.sub.9 = 1.92 n.sub.6 = 1.78472 ν.sub.6 = 25.7 r.sub.10 = 65.907 d.sub.10 = 8.00 n.sub.7 = 1.6935 ν.sub.7 = 53.2 r.sub.11 = -116.042 d.sub.11 = D.sub.3 (variable) r.sub.12 = 36.32 d.sub.12 = 5.05 n.sub.8 = 1.63854 ν.sub.8 = 55.4 r.sub.13 = 108.169 d.sub.13 = 5.72 r.sub.14 = -243.74 d.sub.14 = 3.4 n.sub.9 = 1.56732 ν.sub.9 = 42.8 r.sub.15 = 36.744 d.sub.15 = 5.89 r.sub.16 = 1812.39 d.sub.16 = 5.45 n.sub.10 = 1.62299 ν.sub.10 = 58.1 r.sub.17 = -90.179 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.69 3.249 47.493 24.121 144.97 28.48 22.262 49.352 193.4 49.182 1.56 70.054 ______________________________________ F.sub.II = -0.905F.sub.W F.sub.III = 1.09F.sub.W r.sub.I-1 = 1.293F.sub.W |r.sub.II | = 0.718F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.17899 Δν.sub.I = 24.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 14

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 83.643 d.sub.1 = 6.74 n.sub.1 = 1.6516 ν.sub.1 = 58.7 r.sub.2 = -212.523 d.sub.2 = 2.49 n.sub.2 = 1.64769 ν.sub.2 = 33.8 r.sub.3 = 191.847 d.sub.3 = D.sub.1 (variable) r.sub.4 = -315.514 d.sub.4 = 1.58 n.sub.3 = 1.51633 ν.sub.3 = 64.2 r.sub.5 = 73.972 d.sub.5 = 5.23 r.sub.6 = -50.788 d.sub.6 = 1.58 n.sub.4 = 1.691 ν.sub.4 = 54.8 r.sub.7 = 129.475 d.sub.7 = 4.88 n.sub.5 = 1.68893 ν.sub.5 = 31.1 r.sub.8 = -84.647 d.sub.8 = D.sub.2 (variable) r.sub.9 = 154.659 d.sub.9 = 1.51 n.sub.6 = 1.78472 ν.sub.6 = 25.7 r.sub.10 = 45.712 d.sub.10 = 7.36 n.sub.7 = 1.717 ν.sub.7 = 47.9 r.sub.11 = -90.848 d.sub.11 = D.sub.3 (variable) r.sub.12 = 54.9 d.sub.12 = 5.19 n.sub.8 = 1.6935 ν.sub.8 = 53.2 r.sub.13 = 136.19 d.sub.13 = 8.55 r.sub.14 = -180.558 d.sub.14 = 3.11 n.sub.9 = 1.60717 ν.sub.9 = 40.3 r.sub.15 = 62.987 d.sub.15 = 8.8 r.sub.16 = 206.328 d.sub.16 = 5.15 n.sub.10 = 1.697 ν.sub.10 = 48.5 r.sub.17 = -227.955 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.58 5.936 36.92 14.577 147.62 27.011 15.846 35.651 193 42.146 0.71 50.786 ______________________________________ F.sub.II = - 0.714F.sub.W F.sub.III = 0.86F.sub.W r.sub.I-1 = 0.815F.sub.W |r.sub.II | = 0.495F.sub.W Δ--N.sub.II + Δ--N.sub.III = 1.5299 Δν.sub.I = 24.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 15

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 110.546 d.sub.1 = 8.00 n.sub.1 = 1.60311 ν.sub.1 = 60.7 r.sub.2 = -109.204 d.sub.2 = 2.49 n.sub.2 = 1.5927 ν.sub.2 = 35.3 r.sub.3 = 589.506 d.sub.3 = D.sub.1 (variable) r.sub.4 = 531.834 d.sub.4 = 1.58 n.sub.3 = 1.47069 ν.sub.3 = 67.4 r.sub.5 = 55.243 d.sub.5 = 5.23 r.sub.6 = -50.403 d.sub.6 = 1.49 n.sub.4 = 1.56873 ν.sub.4 = 63.2 r.sub.7 = 48.592 d.sub.7 = 6.3 n.sub.5 = 1.61293 ν.sub.5 = 37 r.sub.8 = -146.241 d.sub.8 = D.sub.2 (variable) r.sub.9 = 95.275 d.sub.9 = 1.51 n.sub.6 = 1.80518 ν.sub.6 = 25.4 r.sub.10 = 42.377 d.sub.10 = 8.00 n.sub.7 = 1.64328 ν.sub.7 = 47.9 r.sub.11 = -93.466 d.sub.11 = D.sub.3 (variable) r.sub.12 = 57.906 d.sub.12 = 3.53 n.sub.8 = 1.72916 ν.sub.8 = 54.7 r.sub.13 = 81.621 d.sub.13 = 5.73 r.sub.14 = -46.913 d.sub.14 = 2.04 n.sub.9 = 1.59551 ν.sub.9 = 39.2 r.sub.15 = 110.375 d.sub.15 = 5.9 r.sub.16 = 1179.425 d.sub.16 = 4.5 n.sub.10 = 1.72916 ν.sub.10 = 54.7 r.sub.17 = -49.279 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.55 6.315 37.547 24.17 147.63 27.39 16.5 45.426 193 42.525 1.364 60.381 ______________________________________ F.sub.II = -0.714F.sub.W F.sub.III = 0.852F.sub.W r.sub.I-1 = 1.078F.sub.W |r.sub.II | = 0.491F.sub.W Δ --N.sub.II + Δ--N.sub.III = 0.25512 Δν.sub.I = 25.4 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 16

A bright and compact optical-compensation type zoom lens system according to claim 5, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 105.943 d.sub.1 = 8.16 n.sub.1 = 1.641 ν.sub.1 = 56.9 r.sub.2 = -88.174 d.sub.2 = 2.56 n.sub.2 = 1.6398 ν.sub.2 = 34.5 r.sub.3 = 413.942 d.sub.3 = D.sub.1 (variable) r.sub.4 = 592.383 d.sub.4 = 1.58 n.sub.3 = 1.47069 ν.sub.3 = 67.4 r.sub.5 = 52.878 d.sub.5 = 5.28 r.sub.6 = -50.695 d.sub.6 = 1.49 n.sub.4 = 1.56384 ν.sub.4 = 60.7 r.sub.7 = 58.485 d.sub.7 = 6.39 n.sub.5 = 1.64769 ν.sub.5 = 33.8 r.sub.8 = -162.423 d.sub.8 = D.sub.2 (variable) r.sub.9 = 98.044 d.sub.9 = 1.51 n.sub.6 = 1.78472 ν.sub.6 = 25.7 r.sub.10 = 41.174 d.sub.10 = 8.01 n.sub.7 = 1.6393 ν.sub.7 = 44.9 r.sub.11 = -90.784 d.sub.11 = D.sub.3 (variable) r.sub.12 = 52.793 d.sub.12 = 3.95 n.sub.8 = 1.617 ν.sub.8 = 62.8 r.sub.13 = 495.894 d.sub.13 = 6.01 r.sub.14 = -79.838 d.sub.14 = 2.16 n.sub.9 = 1.5814 ν.sub.9 = 40.8 r.sub.15 = 61.776 d.sub.15 = 7.38 r.sub.16 = -93.198 d.sub.16 = 5.59 n.sub.10 = 1.6516 ν.sub.10 = 58.7 r.sub.17 = -47.068 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.57 5.641 37.314 6.823 147.62 26.716 16.24 27.897 193 41.851 1.104 43.032 ______________________________________ F.sub.II = -0.714F.sub.W F.sub.III = 0.86F.sub.W r.sub.I-1 = 1.033F.sub.W |r.sub.II | = 0.494F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.27585 Δν.sub.I = 22.4 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 17

A bright and compact optical-compensation type zoom lens system according to claim 1, in which said first lens group I comprises a cemented doublet consisting of a positive lens element and negative lens element, said second lens group II comprises a cemented doublet consisting of a negative lens element and positive lens element, said third lens group III comprises a cemented doublet consisting of a negative lens element and positive lens element, said fourth lens group IV comprises a positive lens component, negative lens component and positive lens component.

Claim 18

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 96.385 d.sub.1 = 8.12 n.sub.1 = 1.6935 ν.sub.1 = 53.2 r.sub.2 = -147.812 d.sub.2 = 2.54 n.sub.2 = 1.68893 ν.sub.2 = 31.1 r.sub.3 = 265.59 d.sub.3 = D.sub.1 (variable) r.sub.4 = -89.008 d.sub.4 = 2.01 n.sub.3 = 1.72 ν.sub.3 = 46.0 r.sub.5 = 32.669 d.sub.5 = 5.13 n.sub.4 = 1.80518 ν.sub.4 = 25.4 r.sub.6 = 94.807 d.sub.6 = D.sub.2 (variable) r.sub.7 = 65.425 d.sub.7 = 1.46 n.sub.5 = 1.78472 ν.sub.5 = 25.7 r.sub.8 = 37.457 d.sub.8 = 9.35 n.sub.6 = 1.51112 ν.sub.6 = 60.5 r.sub.9 = -70.214 d.sub.9 = D.sub.3 (variable) r.sub.10 = 65.873 d.sub.10 = 4.69 n.sub.7 = 1.6935 ν.sub.7 = 53.2 r.sub.11 = -155.394 d.sub.11 = 6.72 r.sub.12 = -43.123 d.sub.12 = 1.57 n.sub.8 = 1.56444 ν.sub.8 = 43.8 r.sub.13 = 68.728 d.sub.13 = 5.44 r.sub.14 = -36.524 d.sub.14 = 5.19 n.sub.9 = 1.72 ν.sub.9 = 50.3 r.sub.15 = -29.335 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.43 5.723 40.817 5.099 147.68 26.045 20.495 25.421 193 40.64 5.9 40.016 ______________________________________ F.sub.II = -0.689F.sub.W F.sub.III = 0.831F.sub.W r.sub.I-1 = 0.941F.sub.W |r.sub.II | = 0.869F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.35878 Δν.sub.I = 22.1 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as whole.

Claim 19

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 90 d.sub.1 = 8.12 n.sub.1 = 1.72 ν.sub.1 = 50.3 r.sub.2 = -188.77 d.sub.2 = 2.54 n.sub.2 = 1.72151 ν.sub.2 = 29.2 r.sub.3 = 211.414 d.sub.3 = D.sub.1 (variable) r.sub.4 = -88.728 d.sub.4 = 2.01 n.sub.3 = 1.72 ν.sub.3 = 46.0 r.sub.5 = 32.722 d.sub.5 = 5.1 n.sub.4 = 1.80518 ν.sub.4 = 25.4 r.sub.6 = 95.135 d.sub.6 = D.sub.2 (variable) r.sub.7 = 66.387 d.sub.7 = 1.46 n.sub.5 = 1.7847 ν.sub.5 = 26.2 r.sub.8 = 37.268 d.sub.8 = 12.28 n.sub.6 = 1.5112 ν.sub.6 = 60.5 r.sub.9 = -67.633 d.sub.9 = D.sub.3 (variable) r.sub.10 = 87.09 d.sub.10 = 6.66 n.sub.7 = 1.741 ν.sub.7 = 52.7 r.sub.11 = -126.453 d.sub.11 = 6.36 r.sub.12 = -40.681 d.sub.12 = 2.58 n.sub.8 = 1.57501 ν.sub.8 = 41.5 r.sub.13 = 95.699 d.sub.13 = 5.36 r.sub.14 = -34.928 d.sub.14 = 4.49 n.sub.9 = 1.757 ν.sub.9 = 47.9 r.sub.15 = -28.783 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.43 4.856 39.398 3.793 147.68 25.178 19.076 24.115 193 39.773 4.481 38.71 ______________________________________ F.sub.II = -0.689F.sub.W F.sub.III = 0.831F.sub.W r.sub.I-1 = 0.879F.sub.W |r.sub.II | = 0.866F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.35878 Δν.sub.I = 21.1 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represent the focal length of the lens system as a whole.

Claim 20

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 113.804 d.sub.1 = 8.12 n.sub.1 = 1.6935 ν.sub.1 = 53.2 r.sub.2 = -112.521 d.sub.2 = 2.54 n.sub.2 = 1.6727 ν.sub.2 = 32.1 r.sub.3 = 424.128 d.sub.2 = D.sub.1 (variable) r.sub.4 = -87.131 d.sub.4 = 2.01 n.sub.3 = 1.72 ν.sub.3 = 43.7 r.sub.5 = 29.983 d.sub.5 = 5.73 n.sub.4 = 1.7847 ν.sub.4 = 26.2 r.sub.6 = 99.986 d.sub.6 = D.sub.2 (variable) r.sub.7 = 64.722 d.sub.7 = 1.46 n.sub.5 = 1.72151 ν.sub.5 = 29.2 r.sub.8 = 34.909 d.sub.8 = 9 n.sub.6 = 1.51112 ν.sub.6 = 60.5 r.sub.9 = -74.582 d.sub.9 = D.sub.3 (variable) r.sub.10 = 68.175 d.sub.10 = 4.22 n.sub.7 = 1.72916 ν.sub.7 = 54.7 r.sub.11 = -179.302 d.sub.11 = 7.03 r.sub.12 = -44.073 d.sub.12 = 1.74 n.sub.8 = 1.57309 ν.sub.8 = 42.6 r.sub.13 = 65.55 d.sub.13 = 5.98 r.sub.14 = -38.983 d.sub.14 = 4.94 n.sub.9 = 1.6935 ν.sub.9 = 53.2 r.sub.15 = -29.562 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.43 7.055 40.819 4.362 147.68 27.377 20.497 24.684 193 41.972 5.902 39.279 ______________________________________ F.sub.II = -0.689F.sub.W F.sub.III = 0.831F.sub.W r.sub.I-1 = 1.111F.sub.W |r.sub.II | = 0.851F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.27509 Δν.sub.I = 21.1 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 21

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 112.359 d.sub.1 = 8.12 n.sub.1 = 1.6935 ν.sub.1 = 53.2 r.sub.2 = -112 d.sub.2 = 2.54 n.sub.2 = 1.68893 ν.sub.2 = 31.1 r.sub.3 = 452.529 d.sub.3 = D.sub.1 (variable) r.sub.4 = -93.072 d.sub.4 = 2.01 n.sub.3 = 1.72 ν.sub.3 = 46 r.sub.5 = 30.606 d.sub.5 = 5.29 n.sub.4 = 1.80518 ν.sub.4 = 25.4 r.sub.6 = 89.243 d.sub.6 = D.sub.2 (variable) r.sub.7 = 62.002 d.sub.7 = 1.46 n.sub.5 = 1.7847 ν.sub.5 = 26.2 r.sub.8 = 35.748 d.sub.8 = 8.67 n.sub.6 = 1.51112 ν.sub.6 = 60.5 r.sub.9 = -73.57 d.sub.9 = D.sub.3 (variable) r.sub.10 = 58.62 d.sub.10 = 4.29 n.sub.7 = 1.741 ν.sub.7 = 52.7 r.sub.11 = -450.663 d.sub.11 = 6.98 r.sub.12 = -52.901 d.sub.12 = 1.79 n.sub.8 = 1.57501 ν.sub.8 = 41.5 r.sub.13 = 55.615 d.sub.13 = 6.1 r.sub.14 = -41.768 d.sub.14 = 5.36 n.sub.9 = 1.757 ν.sub.9 = 47.9 r.sub.15 = -32.06 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 102.43 6.883 41.409 3.978 147.68 27.205 21.087 24.3 193 41.8 6.492 38.895 ______________________________________ F.sub.II = -0.689F.sub.W F.sub.III = 0.831F.sub.W r.sub.I-1 = 1.097F.sub.W |r.sub.II | = 0.909F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.35878 Δν.sub.I = 21.1 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as whole.

Claim 22

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 102.732 d.sub.1 = 5.8 n.sub.1 = 1.641 ν.sub.1 = 56.9 r.sub.2 = -162.479 d.sub.2 = 2.3 n.sub.2 = 1.61293 ν.sub.2 = 37 r.sub.3 = 361.524 d.sub.3 = D.sub.1 (variable) r.sub.4 = -83.421 d.sub.4 = 2.0 n.sub.3 = 1.62012 ν.sub.3 = 49.7 r.sub.5 = 32.836 d.sub.5 = 4.0 n.sub.4 = 1.76182 ν.sub.4 = 26.6 r.sub.6 = 71.388 d.sub.6 = D.sub.2 (variable) r.sub.7 = 121.646 d.sub.7 = 2.1 n.sub.5 = 1.69895 ν.sub.5 = 30.1 r.sub.8 = 33.117 d.sub.8 = 7.3 n.sub.6 = 1.6583 ν.sub.6 = 57.3 r.sub.9 = -88.167 d.sub.9 = D.sub.3 (variable) r.sub.10 = 53.895 d.sub.10 = 4.4 n.sub.7 = 1.6485 ν.sub.7 = 53 r.sub.11 = 365.658 d.sub.11 = 6.5 r.sub.12 = -65.215 d.sub.12 = 2.5 n.sub.8 = 1.57957 ν.sub.8 = 53.8 r.sub.13 = 71.468 d.sub.13 = 3.5 r.sub.14 = -77.557 d.sub.14 = 3.5 n.sub.9 = 1.6485 ν.sub.9 = 53 r.sub.15 = -41.329 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 103.21 5.861 38.303 7.685 150.42 26.861 17.303 28.685 193.98 40.861 3.303 42.685 ______________________________________ F.sub.II = -0.696F.sub.W F.sub.III = 0.822F.sub.W r.sub.I-1 = 0.995F.sub.W |r.sub.II | = 0.808F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.18235 Δν.sub.I = 19.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 23

A bright and compact optical-compensation type zoom lens system according to claim 16, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 92.369 d.sub.1 = 5.18 n.sub.1 = 1.641 ν.sub.1 = 56.9 r.sub.2 = -124.044 d.sub.2 = 2.09 n.sub.2 = 1.61293 ν.sub.2 = 37 r.sub.3 = 319.244 d.sub.3 = D.sub.1 (variable) r.sub.4 = -79.057 d.sub.4 = 1.8 n.sub.3 = 1.6825 ν.sub.3 = 44.7 r.sub.5 = 31.23 d.sub.5 = 4 n.sub.4 = 1.80518 ν.sub.4 = 25.4 r.sub.6 = 76.086 d.sub.6 = D.sub.2 (variable) r.sub.7 = 116.231 d.sub.7 = 1.89 n.sub.5 = 1.74077 ν.sub.5 = 27.8 r.sub.8 = 30.789 d.sub.8 = 7.5 n.sub.6 = 1.697 ν.sub.6 = 48.5 r.sub.9 = -82.003 d.sub.9 = D.sub.3 (variable) r.sub.10 = 65.384 d.sub.10 = 6.4 n.sub.7 = 1.6583 ν.sub.7 = 53.4 r.sub.11 = 560.402 d.sub.11 = 9.47 r.sub.12 = -58.027 d.sub.12 = 3.65 n.sub.8 = 1.57135 ν.sub.8 = 52.9 r.sub.13 = 82.065 d.sub.13 = 4.5 r.sub.14 = -76.837 d.sub.14 = 4.5 n.sub.9 = 1.6583 ν.sub.9 = 57.3 r.sub.15 = -41.224 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 103.47 5.166 32.565 5.851 150.12 23.766 13.965 24.451 193 36.166 1.565 36.851 ______________________________________ F.sub.II = -0.625F.sub.W F.sub.III = 0.731F.sub.W r.sub.I-1 = 0.893F.sub.W |r.sub.II | = 0.764F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.16645 Δν.sub.I = 19.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 24

A bright and compact optical-compensation type zoom lens system according to claim 1, in which said first lens group I comprises a cemented doublet consisting of a positive lens element and negative lens element, said second lens group II comprises a cemented doublet consisting of a negative lens element and positive lens element, said third lens group III comprises a cemented doublet consisting of a negative lens element and positive lens element, and said fourth lens group IV comprises a positive lens component and negative lens component.

Claim 25

A bright and compact optical-compensation type zoom lens system according to claim 23, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 84.518 d.sub.1 = 2.5 n.sub.1 = 1.6398 ν.sub.1 = 34.5 r.sub.2 = 46 d.sub.2 = 5.74 n.sub.2 = 1.641 ν.sub.2 = 56.9 r.sub.3 = 198.951 d.sub.3 D.sub.1 (variable) r.sub.4 = -78.795 d.sub.4 = 2.13 n.sub.3 = 1.56883 ν.sub.3 = 56.1 r.sub.5 = 36.692 d.sub.5 = 4.27 n.sub.4 = 1.78472 ν.sub.4 = 25.7 r.sub.6 = 66.303 d.sub.6 = D.sub.2 (variable) r.sub.7 = 170.898 d.sub.7 = 2.67 n.sub.5 = 1.72825 ν.sub.5 = 28.5 r.sub.8 = 36.304 d.sub.8 = 7.48 n.sub.6 = 1.697 ν.sub.6 = 48.5 r.sub.9 = - 89.32 d.sub.9 = D.sub.3 (variable) r.sub.10 = 96.33 d.sub.10 = 4 n.sub.7 = 1.6516 ν.sub.7 = 58.7 r.sub.11 = 249.545 d.sub.11 = 2.43 r.sub.12 = -135.661 d.sub.12 = 4 n.sub.8 = 1.53256 ν.sub.8 = 45.9 r.sub.13 = -255.847 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 103.28 4.908 43.74 8.179 150 26.961 21.687 30.232 193.59 41.761 6.887 45.032 ______________________________________ F.sub.II = -0.73F.sub.W F.sub.III = 0.877F.sub.W r.sub.I-1 = 0.818F.sub.W |r.sub.II | = 0.763F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.24714 Δν.sub.I = 22.4 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.

Claim 26

A bright and compact optical-compensation type zoom lens system according to claim 23, in which said zoom lens system having the following numerical data: ______________________________________ r.sub.1 = 84.075 d.sub.1 = 6.2 n.sub.1 = 1.641 ν.sub.1 = 56.9 r.sub.2 = -170.085 d.sub.2 = 2.3 n.sub.2 = 1.61293 ν.sub.2 = 37 r.sub.3 = 190.102 d.sub.3 = D.sub.1 (variable) r.sub.4 = -75.21 d.sub.4 = 2 n.sub.3 = 1.57135 ν.sub.3 = 52.9 r.sub.5 = 35.178 d.sub.5 = 4 n.sub.4 = 1.78472 ν.sub.4 = 25.7 r.sub.6 = 64.055 d.sub.6 = D.sub.2 (variable) r.sub.7 = 148.889 d.sub.7 = 2.2 n.sub.5 = 1.7285 ν.sub.5 = 28.5 r.sub.8 = 34.759 d.sub.8 = 7.5 n.sub.6 = 1.697 ν.sub.6 = 48.5 r.sub. 9 = -90.578 d.sub.9 = D.sub.3 (variable) r.sub.10 = 108.982 d.sub.10 = 3 n.sub.7 = 1.691 ν.sub.7 = 54.8 r.sub.11 = 417.251 d.sub.11 = 1.97 r.sub.12 = -135.649 d.sub.12 = 4.2 n.sub.8 = 1.53172 ν.sub.8 = 48.9 r.sub.13 = -368.112 ______________________________________ F D.sub.1 D.sub.2 D.sub.3 ______________________________________ 103.45 5.595 42.225 12.463 149.94 26.582 21.238 33.45 193 40.615 7.205 47.483 ______________________________________ F.sub.II = -0.696F.sub.W F.sub.III = 0.84F.sub.W r.sub.I-1 = 0.813F.sub.W |r.sub.II | = 0.727F.sub.W Δ--N.sub.II + Δ--N.sub.III = 0.24462 Δν.sub.I = 19.9 ______________________________________ wherein reference symbols r 1 , r 2 , . . . respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 , . . . respectively represent thicknesses of respective lenses and airspaces between respective lenses, reference symbols n 1 , n 2 , . . . respectively represent refractive indices of respective lenses, reference symbols ν 1 , ν 2 , . . . respectively represent Abbe's numbers of respective lenses, and reference symbol F represents the focal length of the lens system as a whole.