Zoom lens

Claim 2

A zoom lens comprising from the object end a foremost positive focusing group consisting of two doublets of positive power movable axially of said lens, and further comprising in succession a stationary group of weak optical power a variator group and a compensator group both movable axially of the lens at different rates to vary the equivalent focal length thereof, and a stationary master lens.

Claim 3

A zoom lens as defined in claim 1 wherein the focusing group has an equivalent focal length in the range between 1.0 and 1.4 times the lower limit of the equivalent focal length range of said lens.

Claim 4

A zoom lens as defined in claim 1 wherein the doublets comprising said front focusing group have equivalent focal lengths which differ from each other by no more than thirty-five percent.

Claim 5

A zoom lens as defined in claim 3 wherein the object side doublet of said focusing group has a larger equivalent focal length than does the image side doublet.

Claim 6

A zoom lens as defined in claim 1 wherein the weak stationary group has an equivalent focal length with an absolute value greater than twice the upper limit of the equivalent focal length range of said lens.

Claim 7

A zoom lens as defined in claim 1 wherein the variator group has an equivalent focal length in the range between four-tenths and six-tenths of the lower limit of the equivalent focal length range of said lens.

Claim 8

A zoom lens as defined in claim 1 wherein the compensator group has an equivalent focal length in the range between 1.5 times the lower limit of the equivalent focal length of said lens and the upper limit of the equivalent focal length range of said lens.

Claim 9

A lens as defined in claim 1 wherein said lens subtends a semi-field angle which is variable between 6.3 degrees and 12.6 degrees.

Claim 10

The zoom lens of claim 1 defined substantially by the following data as scaled to an EFL which varies from substantially 90mm to substantially 180mm, for a 24×36 mm image frame and a BFL of 40.9mm: ______________________________________ Index Axial of Re- Distance frac- Abbe Ele- Radius of Between tion No. ment Curvature (mm) Surfaces (mm) N.sub.d V.sub.d ______________________________________ R1 = 224.298 L1 D1 = 3.500 1.805 25.5 R2 = 108.890 L2 D2 = 7.800 1.643 47.9 R3 = -307.317 D3 = 0.300 R4 = 67.511 L3 D4 = 3.500 1.805 25.5 R5 = 50.481 L4 D5 = 10.100 1.487 70.4 R6 = 1962.678 D6 = 2.400 R7 = -151.829 L5 D7 = 3.000 1.773 49.6 R8 = 274.046 D8 = 1.758 R9 = -515.802 L6 D9 = 4.000 1.757 36.3 R10 = -111.178 D10 = 1.00 R11 = -128.760 L7 D11 = 2.000 1.569 63.1 R12 = 46.925 D12 = 3.500 R13 = - 66.815 L8 D13 = 2.000 1.623 58.1 R14 = 35.262 L9 D14 = 6.223 1.728 28.3 R15 = 1462.528 D15 = 23.31 R16 = 380.580 L10 D16 = 4.110 1.487 70.4 R17 = - 35.6976 L11 D17 = 2.000 1.805 25.5 R18 = - 56.161 D18 = 15.10 R19 = 62.904 L12 D19 = 3.392 1.487 70.4 R20 = 345.723 D20 = 0.100 R21 = 29.223 L13 D21 = 6.915 1.487 70.4 R22 = 1139.097 L14 D22 = 1.972 1.689 31.2 R23 = 81.429 D23 = 25.546 R24 = 103.463 L15 D24 = 3.580 1.805 25.5 R25 = -1071.644 D25 = 7.757 R26 = - 22.798 L16 D26 = 2.080 1.834 37.3 R27 = 43.784 L17 D27 = 7.155 1.487 70.4 R28 = - 49.400 D28 = 0.100 R29 = 57.055 L18 D29 = 4.84 1.805 25.5 R30 = 251.679 ______________________________________ Where L1-L18 are successive lens elements arranged in five groups as follows: L1,L2,L3,L4; L5,L6: L7,L8,L9; L10,L11; L12,L13,L14,L15,L16,L17,L18; R1-R30 are the radii of curvature of the successive lens surfaces according to the sequence of surfaces of the lens system, said lens further having an aperture stop situated between said elements L11 and L12 and wherein said space D6 varies for focusing and spaces D10, D15 and D18 vary for zooming.

Claim 11

The zoom lens of claim 1 defined substantially by the following data, as scaled to a EFL which varies from substantially 90mm to substantially 180mm for a 24×36mm image frame and having a BFL of 39.45mm: ______________________________________ Index Axial of Re- Distance frac- Abbe Ele- Radius of Between tion No. ment Curvature (mm) Surfaces (mm) N.sub.d V.sub.d ______________________________________ R1 = 193.173 L1 D1 = 3.500 1.805 25.5 R2 = 107.852 L2 D2 = 7.800 1.643 47.9 R3 = -422.164 D3 = 0.300 R4 = 71.823 L3 D4 = 3.500 1.805 25.5 R5 = 52.616 L4 D5 = 10.100 1.487 70.4 R6 = 3557.617 D6 = 2.400 R7 = -183.735 L5 D7 = 3.000 1.773 49.6 R8 = 326.100 D8 = 2.100 R9 = -408.992 L6 D9 = 4.000 1.757 36.3 R10 = -125.018 D10 = 0.447 R11 = -158.759 L7 D11 = 2.000 1.569 63.1 R12 = 46.015 D12 = 4.700 R13 = -60.810 L8 D13 = 2.000 1.623 58.1 R14 = 38.624 L9 D14 = 4.800 1.728 28.3 R15 = -750.885 D15 = 23.53 R16 = 1799.986 L10 D16 = 6.500 1.487 70.4 R17 = -37.824 L11 D17 = 2.000 1.805 25.5 R18 = -58.979 D18 = 14.35 R19 = 63.206 L12 D19 = 3.392 1.487 70.4 R20 = 1069.561 D20 = 0.569 R21 = 29.700 L13 D21 = 7.453 1.487 70.4 R22 = -1988.280 L14 D22 = 1.972 1.689 31.2 R23 = 80.811 D23 = 25.135 R24 = 80.998 L15 D24 = 3.580 1.805 25.5 R25 = 395.878 D25 = 8.443 R26 = -23.362 L16 D26 = 2.080 1.834 37.3 R27 = 37.378 D27 = 0.100 R28 = 37.246 L17 D28 = 7.290 1.487 70.4 R29 = -51.068 D29 = 0.071 R30 = 55.817 L18 D30 = 4.840 1.805 25.5 R31 = 364.939 ______________________________________ Where L1-L18 are successive lens elements arranged in five groups as follows: L1,L2,L3,L4; L5,L6; L7,L8,L9; L10,L11; L12,L13,L14,L15,L16,L17,L18; R1-R-31 are the radii of curvature of the successive lens surfaces according to the sequence of surfaces of the lens system, said lens further having an aperture stop between L11 and L12, and wherein said space D6 varies for focusing and spaces D10, D15 and D18 vary for zooming.

Claim 12

The zoom lens of claim 1 defined substantially by the following data, as scaled to an EFL which varies from substantially 90mm to substantially 180mm for a 24×36mm image frame and having a BFL of 38.5mm: ______________________________________ Index Axial of Re- Distance frac- Abbe Ele- Radius of Between tion No. ment Curvature (mm) Surfaces (mm) N.sub.d V.sub.d ______________________________________ R1 = 165.484 L1 D1 = 3.500 1.805 25.5 R2 = 96.900 L2 D2 = 7.800 1.643 47.9 R3 = -463.158 D3 = 0.300 R4 = 74.597 L3 D4 = 3.500 1.805 25.5 R5 = 53.370 L4 D5 = 10.100 1.487 70.4 R6 = 2690.21 D6 = 1.700 R7 = -207.207 L5 D7 = 3.000 1.773 49.6 R8 = 323.884 D8 = 2.100 R9 = -375.195 L6 D9 = 4.000 1.757 36.3 R10 = -132.727 D10 = 0.50 R11 = -153.141 L7 D11 = 2.000 1.569 63.1 R12 = 46.039 D12 = 4.700 R13 = -60.530 L8 D13 = 2.000 1.623 58.1 R14 = 38.694 L9 D14 = 4.800 1.728 28.3 R15 = -615.592 D15 = 24.12 R16 = 1842.93 L10 D16 = 6.500 1.487 70.4 R17 = -37.907 L11 D17 = 2.000 1.805 25.5 R18 = -59.123 D18 = 13.71 R19 = 85.793 L12 D19 = 3.870 1.487 70.4 R20 = -177.169 D20 = 0.300 R21 = 29.084 L13 D21 = 8.112 1.487 70.4 R22 = 4455.9 L14 D22 = 2.000 1.664 35.9 R23 = 68.631 D23 = 37.956 R24 = -20.551 L15 D24 = 1.600 1.834 37.3 R25 = 55.025 L16 D25 = 7.000 1.487 70.4 R26 = -31.595 D26 = 0.267 R27 = 61.494 L17 D27 = 5.000 1.805 25.5 R28 -300.169 ______________________________________ Where L1-L17 are successive lens elements arranged in five groups as follows: L1,L2,L3,L4; L5,L6; L7,L8,L9; L10,L11; L12,L13,L14,L15,L16,L17; R1-R28 are the radii of curvature of the successive lens surfaces according to the sequence of surfaces of the lens system, said lens further having an aperture stop between L11 and L12, and wherein said space D6 varies for focusing and spaces D10, D15 and D18 vary for zooming.

Claim 13

The zoom lens of claim 1 defined substantially by the following data, as scaled to an EFL which varies from substantially 90mm to substantially 180mm for a 24×36mm image frame and having a BFL of 38.2: TABLE VII ______________________________________ Index Axial of Re- Distance frac- Abbe Ele- Radius Between tion No. ment Curvature (mm) Surfaces (mm) N.sub.d V.sub.d ______________________________________ R1 = 149.310 L1 D1 = 3.500 1.805 25.5 R2 = 107.429 L2 D2 = 7.300 1.639 45.1 R3 = -2049.682 D3 = 0.300 R4 = 83.806 L3 D4 = 3.500 1.805 25.5 R5 = 56.142 L4 D5 = 10.500 1.487 70.4 R6 = -1643.263 D6 = 42.000 R7 = -218.640 L5 D7 = 3.000 1.773 49.6 R8 = 1561.668 D8 = 2.100 R9 = -340.717 L6 D9 = 4.000 1.757 36.3 R10 = -151.315 D10 = 0.500 R11 = -166.461 L7 D11 = 2.000 1.569 63.1 R12 = 47.339 D12 = 4.700 R13 = - 61.492 L8 D13 = 2.000 1.620 60.3 R14 = 40.353 L9 D14 = 4.800 1.728 28.3 R15 = -2054.720 D15 = 25.786 R16 = 430.672 L10 D16 = 6.500 1.487 70.4 R17 = - 37.183 L11 D17 = 2.000 1.805 25.5 R18 = - 59.066 D18 = 14.054 R19 = 81.384 L12 D19 = 3.870 1.487 70.4 R20 = -187.530 D20 = 0.300 R21 = 29.707 L13 D21 = 8.112 1.487 70.4 R22 = 304.826 L14 D22 = 2.000 1.664 35.9 R23 = 58.333 D23 = 39.309 R24 = -20.933 L15 D24 = 1.600 1.834 37.3 R25 = 65.666 L16 D25 = 7.000 1.487 70.4 R26 = - 33.525 D26 = 0.267 R27 = 68.486 L17 D27 = 4.500 1.805 25.5 R28 = -189.489 ______________________________________ Where L1-L17 are successive lens elements arranged in five groups as follows; L1,L2,L3,L4; L5,L6; L7,L8,L9; L10,L11; L12,L13,L14,L15,L16,L17; R1-R28 are the radii of curvature of the successive lens surfaces according to the sequence of surfaces of the lens system, said lens further having an aperture stop between L11 and L12 and wherein said space D6 varies for focusing and spaces D10, D15 and D18 vary for zooming.