USRE32923EExpiredUtility
Zoom lens
Priority: Jan 31, 1980Filed: Oct 10, 1984Granted: May 16, 1989
Est. expiryJan 31, 2000(expired)· nominal 20-yr term from priority
G02B 15/144113
26
PatentIndex Score
13
Cited by
10
References
1
Claims
Abstract
A lens of variable equivalent focal length where two lens groups located on either side of an aperture defining means move relative to the aperture defining means, and a lens group of positive power is positioned close to the aperture defining means. The aperture defining means and the associated positive power group may either be stationary or move with change in equivalent focal length.
Claims
exact text as granted — not AI-modifiedWhat I claim is:
1. A lens of variable equivalent focal length .Iadd.extending from a dimension below the diagonal of the image frame of the lens to a dimension substantially above .Iaddend.comprising from the object end a first positive group, a second negative group, an aperture defining means, a third positive group closely spaced in fixed relation to the aperture defining means, and a fourth positive group, said .[.second.]. .Iadd.first .Iaddend.and fourth groups being movable .Iadd.in the same direction .Iaddend.to vary the equivalent focal length of the lens, .Iadd.while said second group moves in the opposite direction, .Iaddend.said third group and said aperture defining means remaining stationary during change in equivalent focal length.Iadd., said second group being of strong negative optical power, and
5. 0>|K 2 /K G |>2.0 where K 2 is the optical power of said second group and K G is the geometric mean of the powers of said lens at the extremes of its equivalent focal lengths. .Iaddend. .[.2. The lens of claim 1 wherein said first group also moves to vary the equivalent focal length of said
lens..]. 3. The lens of claim .[.2.]. .Iadd.1 .Iaddend.wherein said first
and fourth groups move in fixed relation. 4. The lens of claim 1 where all
of said groups move in fixed relation to focus said lens. 5. The lens of claim 1 wherein said third group comprises a single element and ##EQU2## where the image side surface of said element is defined on a radius R I and the object side surface of said element is defined on a radius
R o . 6. The lens of claim 1 wherein said third group comprises two
elements. 7. The lens of claim 6 wherein said third group comprises a
negative meniscus and a biconvex element. 8. The lens of claim 1 wherein: 0.3>K.sub.3 /K.sub.G Z.sub.R >0.15 where K 3 is the power of the third group K G is the geometric mean of the powers of the lens at the extremes of its focal length range, and
Z R is the zoom ratio of the lens. 9. The lens of claim 1 wherein: 1.3>K.sub.3 /K.sub.G >0.4 where K 3 is the power of the third group, and K G is the geometric mean of the powers of the lens at the extremes of
its focal length range. .[.10. In a lens of variable focal length, of the type where a negative group on the object side of an aperture defining means and a positive group on the image side of the aperture defining means move axially with respect to the aperture defining means to vary the equivalent focal length of the lens, the improvement comprising, a positive lens component closely, positioned to said aperture defining means and in fixed relation thereto; said aperture defining means and said positive lens component remaining stationary during variation of the equivalent focal length..]. .[.11. The lens of claim 10 wherein: 0.3>K.sub.3 /K.sub.G Z.sub.R >0.15 where K 3 is the power of said positive lens component K G is the geometric means of the powers of the lens at the extremes of its focal length range, and Z R is the zoom ratio of the lens..]. .[.12. The lens of claim 10 wherein: 1.3>K.sub.3 /K.sub.G >0.4..].
13. The lens of claim 1 where the power of said positive group in fixed relation to the aperture defining means is substantially equal to or
greater than the power of said front group. 14. The lens of claim 1 where the power of said positive group in fixed relation to the aperture defining means is substantially equal to or less than the geometric mean
power of said lens. 15. The lens of claim 1 where the power of said third group is substantially equal to or greater than the power of said first group and substantially equal to or less .[.then.]. .Iadd.than .Iaddend.the geometric mean of the powers of the lens at the extremes of
its equivalent focal lengths. 16. A zoom lens .Iadd.having a range of equivalent focal lengths from a dimension below the diagonal of the image frame of said lens to substantially above .Iaddend.comprising means defining a variable aperture, a first positive and a second negative lens group on the object side of said aperture defining means, .Iadd.and .Iaddend.a .Iadd.rear .Iaddend.positive group on the image side of said aperture defining means, said .Iadd.first, second and rear .Iaddend.lens groups being axially movable with respect to said aperture defining means to vary the equivalent focal length of said lens and a third positive group closely positioned to said aperture defining means and in fixed relation thereto, said third group being stationary as said other groups are moved to vary the equivalent focal length, all of said groups being
movable in fixed relation to focus said lens. 17. The lens of claim 16 wherein said positive group on the object side of said negative group and said positive group on the image side of said aperture defining means move
in fixed relation with variation in equivalent focal length. 18. The lens of claim 16 where the group in fixed relation to said aperture defining means has an optical power K 3 , the geometric mean power of said lens is K G , and lens has a zoom ratio Z R , and 0.25>K.sub.3 /K.sub.G Z.sub.R >0.15 .Iadd.and where K 3 is the optical power of said third group, K G is the geometric mean of the optical powers of said lens at the extremes of its equivalent focal length range and Z R is the zoom ratio of said
lens. .Iaddend. 19. The lens of claim 16 where 0.006>K.sub.3 /Z.sub.R >0.003 .Iadd.where K 3 is the optical power of said lens expressed as the reciprocal of its equivalent focal length in millimeters, and Z R is
the zoom ratio of said lens. .Iaddend. 20. The lens of claim 16 where 1.2>K.sub.3 /K.sub.G >0.4 .Iadd.and where K 3 is the optical power of said third group, and K G is the geometric mean of the optical powers of said lens at the
extremes of its equivalent focal length range. .Iaddend. 21. A lens according to claim 1 as scaled to an equivalent focal length of 28.5 to 87.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
S1 878.67
L1 3.00 1.805
25.5
S2 53.00
1.80
S3 54.94
L2 8.70 1.786
43.9
S4 -295.19
0.15
S5 49.87
L3 4.30 1.835
43.0
S6 100.18
Z1
S7 83.91
L4 2.00 1.850
32.2
S8 17.34
4.80
S9 -116.10
L5 2.00 1.835
43.0
S10 33.18
.20
S11 25.25
L6 11.54 1.728
28.3
S12 -17.23
L7 1.50 1.835
43.0
S13 -826.07
Z2
aperture
1.00
S14 55.92
L8 2.23 1.667
48.3
S15 1165.66
Z3
S16 28.44
L9 4.79 1.613
58.6
S17 -41.59
0.79
S18 -28.11
L10 12.00 1.593
35.6
S19 38.61
2.68
S20 -145.85
L11 3.00 1.835
43.0
S21 -31.12
0.20
S22 51.53
L12 5.97 1.573
42.6
S23 -23.68
0.99
S24 21.43
L13 1.60 1.805
25.5
S25 -993.13
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
28.6 mm 156.4 mm .80 mm 15.3 mm
14.7 mm
43.6
40.0 161.3 10.4 10.4 10.3 48.5
55.0 165.0 18.6 6.5 6.0 53.1
87.0 171.7 29.2 1.0 0.8 58.9
______________________________________
where L1-L13 are lens elements from the object end; S1-S15 are the lens surfaces from the object end with positive radii struck from the right and negative .[.ratii.]. .Iadd.radii .Iaddend.struck from the left; N d is the index of refraction of the lens element; V d is the Abbe number of the lens elements; Z1, Z2 and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex
distance; and BFL is the back focal length. 22. A lens according to claim 1 as scaled to an equivalent focal length of 28.5 to 87.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
S1 649.67
L1 3.00 1.805
25.5
S2 57.37
1.80
S3 58.75
L2 8.70 1.700
47.8
S4 -237.36
0.15
S5 52.91
L3 4.30 1.834
37.3
S6 120.92
Z1
S7 70.22
L4 2.00 1.805
25.5
S8 17.07
5.10
S9 -64.49
L5 2.00 1.589
61.3
S10 25.54
0.50
S11 22.97
L6 7.17 1.699
30.1
S12 -18.35
L7 7.17 1.699
30.1
S13 158.15
Z2
aperture
1.30
S14 61.35
L8 2.23 1.723
38.0
S15 -697.26
Z3
S16 31.91
L9 4.79 1.658
57.3
S17 -40.93
0.60
S18 -28.41
L10 13.30 1.593
35.5
S19 40.69
2.84
S10 -65.65
L11 3.00 1.583
46.5
S21 -27.15
0.20
S22 50.97
L12 7.25 1.517
52.2
S23 -23.28
1.79
S24 -20.86
L13 1.60 1.847
23.8
S25 -56.24
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
28.6 mm 156.5 mm 0.8 mm 15.1 mm
16.4 mm
42.5 mm
40.0 161.8 10.6 20.4 11.3 47.8
55.0 166.7 19.0 6.7 6.6 52.8
87.0 173.3 29.8 1.8 0.8 59.3
______________________________________
where L1-L13 are lens elements from the object end; S1-S25 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2 and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is the
back focal length. 23. A lens according to claim 1 as scaled to an equivalent focal length of 28.5 to 87.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
S1 367.16
L1 3.00 1.805
25.5
S2 53.15
1.80
S3 54.36
L2 8.90 1.700
47.8
S4 -220.65
0.15
S5 46.30
L3 4.00 1.834
37.3
S6 83.28
Z1
S7 59.28
L4 2.00 1.805
25.5
S8 16.09
5.04
S9 -59.80
L5 2.00 1.609
59.2
S10 28.34
0.50
S11 23.44
L6 8.00 1.699
30.1
S12 -17.37
L7 1.50 1.804
46.5
S13 110.83
Z2
aperture
1.30
S14 63.48
L8 2.00 1.834
37.3
S15 -659.47
Z3
S16 32.68
L9 4.79 1.661
57.0
S17 -42.95
0.60
S18 -29.12
L10 12.32 1.593
35.5
S19 43.26
3.27
S20 -229.66
L11 3.80 1.543
46.9
S21 -29.26
0.20
S22 57.54
L12 7.65 1.517
52.2
S23 -24.09
1.54
S24 -21.66
L13 1.80 1.847
23.8
S25 -68.41
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
28.6 mm 156.3 mm 0.84 mm 13.30 mm
17.20 mm
42.3 mm
48.0 161.8 10.32 9.14 11.89 47.8
55.0 167.0 18.36 5.95 7.03 53.0
87.0 174.3 28.70 1.78 .86 60.3
______________________________________
where L1-L13 are lens elements from the object end; S1-S25 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2, and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is
the back focal length. 24. A lens according to claim 1 as scaled to an equivalent focal length of 25.5 to 124.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
S1 143.67
L1 3.00 1.805
25.5
S2 45.42
0.03
S3 45.12
L2 13.33 1.476
70.4
S4 -417.52
0.10
S5 43.91
L3 6.94 1.868
41.2
S6 143.05
Z1
S7 99.50
L4 2.00 1.860
22.8
S8 -85.74
L5 1.50 1.856
40.0
S9 12.47
5.26
S10 -41.14
L6 2.00 1.847
44.5
S11 36.97
0.20
S12 23.01
L7 6.81 1.711
26.7
S13 -13.81
L8 2.00 1.836
31.1
S14 -91.05
Z2
aperture
1.50
S15 29.03
L9 1.63 1.847
23.8
S16 23.58
3.32
S17 38.96
L10 4.55 1.487
70.4
S18 -40.98
Z3
S19 39.92
L11 6.00 1.487
70.4
S10 -109.09
0.50
S21 32.42
L12 8.48 1.465
65.8
S22 -173.96
L13 2.00 1.600
38.4
S23 29.36
1.86
S24 54.84
L14 2.05 1.835
63.0
S25 19.80
L15 11.48 1.465
65.8
S26 -20.07
0.79
S27 -18.95
L16 2.50 1.835
63.0
S28 -34.13
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
25.5 mm
179.0 mm 1.00 mm 17.58 mm
16.54 mm
39.0 mm
40.0 179.6 9.53 11.05 13.26 51.0
85.0 185.4 28.96 5.68 1.44 54.5
124.0 190.9 34.31 1.25 1.53 59.0
______________________________________
where L1-L16 are lens elements from the object end; S1-S28 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2 and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is the
back focal length. 25. A lens according to claim 1 as scaled to an equivalent focal length of 25.5 to 124.0 mm for a 24×36 mm image frame defined substantially as follows: __________________________________________________________________________
Surface Radius
Axial Distance Between
Lens
Surface
(mm) Surfaces (mm)
N.sub.d
V.sub.d
__________________________________________________________________________
S1 169.45
L1 3.00 1.805
25.5
S2 56.72
0.41
S3 56.53
L2 12.60 1.487
70.4
S4 -605.21
0.10
S5 54.35
L3 6.9 1.834
37.3
S6 151.66
Z1
S7 95.83
L4 1.50 1.834
37.3
S8 14.79
7.53
S9 -65.44
L5 2.00 1.835
63.0
S10 42.84
0.20
S11 27.06
L6 15.72 1.741
27.8
S12 -26.96
L7 1.53 1.773
49.6
S13 -508.18
Z2
aperture
S14 33.47
L8 1.50 1.847
23.8
S15 25.18
2.66
S16 32.36
L9 4.55 1.487
70.4
S17 -58.18
Z3
S18 38.94
L10 6.00 1.564
60.8
S19 1862.11
10.93
S20 94.60
L11 2.00 1.850
32.2
S21 22.04
L12 11.50 1.471
67.3
S22 -25.15
S23 -21.83
L13 2.00 1.620
60.3
S24 -47.40
__________________________________________________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
__________________________________________________________________________
25.5 mm
198.8 mm
1.000 mm
28.636 mm
27.353 mm
40.0 mm
40.0
198.3 12.482 16.261 13.378 44.6
85.0
214.1 37.390 5.983 2.061 67.1
124.0
220.1 47.590 .874 .700 69.3
__________________________________________________________________________
where L1-L13 are lens elements from the object end; S1-S24 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens element; V d is the Abbe number of the lens elements; Z1, Z2 and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is the
back focal length. 26. A lens according to claim 1 as scaled to an equivalent focal length of 25.5 to 124.0 mm for a 24×36 mm image frame defined substantially as follows: __________________________________________________________________________
Surface Radius
Axial Distance Between
Lens
Surface
(mm) Surfaces (mm)
N.sub.d
V.sub.d
__________________________________________________________________________
S1 188.72
L1 3.00 1.806
25.5
S2 56.11
0.38
S3 56.11
L2 12.20 1.487
70.4
S4 -608.85
S5 55.24
L3 6.94 1.834
37.3
S6 172.29
Z1
S7 99.95
L4 1.50 1.834
37.3
S8 14.45
6.83
S9 -63.20
L5 2.00 1.835
43.0
S10 42.33
0.20
S11 26.50
L6 14.4 1.761
26.8
S12 -28.98
L7 1.53 1.743
49.2
S13 -699.54
Z2
aperture
2.05
S14 33.36
L8 1.50 1.847
23.8
S15 24.83
2.50
S16 31.37
L9 4.55 1.762
26.9
S17 -56.74
Z3
S18 38.07
L10 6.00 1.570
60.1
S19 1365.55
11.47
S20 88.72
L11 2.00 1.850
32.2
S21 21.05
L12 11.50 1.471
67.3
S22 -25.14
1.47
S23 21.79
L13 2.00 1.591
63.0
S24 -47.99
__________________________________________________________________________
ZOOM LENS
EFL FVD Z1 Z2 Z3 BFL
__________________________________________________________________________
25.5 mm
194.6 mm
0.800 mm
26.957 mm
27.515 mm
40.1 mm
40.0
194.8 12.491 15.244 13.209 54.7
85.0
212.2 38.085 5.614 1.817 67.4
124.0
219.0 48.820 0.874 0.700 69.4
__________________________________________________________________________
wherein L1-L13 are lens elements from the object end; S1-S24 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2, and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is
the back focal length. 27. A lens according to claim 1 as scaled to an equivalent focal length of 25.5 to 124.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
S1 131.80
L1 3.00 1.805 25.5
S2 45.99
0.40
S3 45.95
L2 13.33 1.487 70.4
S4 -352.60
0.10
S5 44.42
L3 6.94 1.806 40.7
S6 145.11
Zl
S7 138.87
L4 2.00 1.847 23.8
S8 -78.66
L5 1.50 1.834 37.3
S9 13.60
5.26
S10 -53.44
L6 2.00 1.835 43.0
S11 29.14
0.20
S12 20.88
L7 10.12 1.717 29.5
S13 -12.94
L8 2.00 1.806 40.7
S14 -475.25
Z2
aperture
1.50
S15 32.75
L9 1.50 1.805 25.5
S16 24.09
1.41
S17 31.62
L10 4.55 1.487 70.4
S18 -44.76
Z3
S19 42.56
Lll 6.00 1.487 70.4
S20 -72.65
0.20
S21 29.20
L12 10.00 1.487 70.4
S22 -42.37
L13 2.00 1.548 45.8
S23 24.84
2.00
S24 50.95
L14 2.05 1.786 43.9
S25 18.30
L15 11.00 1.511 60.5
S26 -18.72
L16 2.00 1.806 40.7
S27 -50.49
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
25.5 mm
185.0 mm 1.000 mm 11.408 mm
37.476 mm
38.5
mm
40.0 185.0 9.669 6.664 23.055 49.0
85.0 185.0 29.817 3.579 5.742 49.2
124.0 185.0 35.019 0.150 0.401 52.8
______________________________________
where L1-L16 are lens elements from the object end; S1-S27 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2, and Z3 are variable during change in equivalent focal length; EFL is the equivalent focal length; FVD is the front vertex distance; and BFL is
the back focal length. 28. A lens according to claim 1 as scaled to an equivalent focal length of 25.5 to 124.0 mm for a 24×36 mm image frame defined substantially as follows: ______________________________________
Surface Axial Distance
Radius Between Surfaces
Lens Surface (mm) (mm) N.sub.d
V.sub.d
______________________________________
Sl 142.69
Ll 3.00 1.805 25.5
S2 46.13
0.40
S3 46.01
L2 13.33 1.487 70.4
S4 -487.79
0.10
S5 44.75
L3 6.94 1.806 40.7
S6 145.88
Z1
S7 106.19
L4 2.00 1.847 23.8
S8 -73.61
L5 1.50 1.834 37.3
S9 12.93
5.26
S10 -49.58
L6 2.00 1.835'
43.0
S11 39.03
0.20
S12 21.94
L7 14.07 1.717 29.5
S13 -13.02
L8 2.00 1.806 40.1
S14 584.71
Z2
Aperture
2.05
S15 31.39
L9 1.50 1.805 25.5
S16 23.71
1.58
S17 31.06
L10 4.55 1.487 70.4
S18 -51.85
Z3
S19 43.25
L11 6.00 1.487 70.4
S20 -70.85
0.20
S21 27.36
L12 10.00 1.487 70.4
S22 -43.76
L13 2.00 1.541 47.2
S23 23.42
2.00
S24 45.83
L14 2.05 1.786 43.9
S25 16.77
L15 11.00 1.511 60.5
S26 -18.30
L16 2.00 1.806 40.7
S27 -52.02
______________________________________
ZOOM DATA
EFL FVD Z1 Z2 Z3 BFL
______________________________________
25.5 mm
179.l mm 1.000 mm 11.328 mm
26.53 mm
38.5
mm
40.0 183.3 9.993 6.959 15.013 50.6
85.0 194.9 30.520 3.333 3.717 56.6
124.0 203.1 35.169 0.292 0.500 66.4
______________________________________
where L1-L16 are lens elements from the object end; S1-S27 are the lens surfaces from the object end with positive radii struck from the right and negative radii struck from the left; N d is the index of refraction of the lens elements; V d is the Abbe number of the lens elements; Z1, Z2 and Z3 are variable during change in equivalent focal length; EFL is the equivalent length; FVD is the front vertex distance; and BFL is the back
focal length. 29. A lens of variable equivalent focal length consisting from the object end a first positive group, a second negative group, a third positive group, and a fourth positive group, an aperture defining means closely positioned to said third group and in fixed relation, said .Iadd.first, .Iaddend.second and fourth groups being axially movable to vary the equivalent focal length of the lens, said third group and said aperture defining means being stationary as the equivalent focal length of
the lens is varied. 30. The lens of claim 29 where 0.5<K.sub.1 /K.sub.G <1.0 2.0<|K.sub.2 /K.sub.G |<5.0 0.4<K.sub.3 /K.sub.G <1.2 0.5<K.sub.4 /K.sub.G <1.3 where K 1 , K 2 , K 3 and K 4 are the powers of said first, second, third and fourth groups respectively, and K G is the geometric mean of the powers of said lens at the extremes of its equivalent focal
lengths. 31. A lens .Iadd.of variable equivalent focal length extending from a dimension below the diagonal of the image frame of the lens to a dimension substantially above .Iaddend.for a camera having a 24×36 mm image frame comprising from the object end, a first positive group, a second negative group, a third positive group, and a fourth positive group, said .Iadd.first, .Iaddend.second and fourth groups being movable simultaneously .[.in opposite directions.]. to vary the equivalent focal length of said lens, .Iadd.said first and fourth groups being movable in the same direction, .Iaddend.said third lens group being stationary, an aperture defining means closely spaced to said third group and in fixed relation thereto, and 0.015>K.sub.1 >0.010 0.080>|K.sub.2 |>0.040 0.019>K.sub.3 >0.010 0.023>K.sub.4 >0.010 where K 1 , K 2 , K 3 , and K 4 , are the optical powers of said first, second, third, and fourth groups expressed as the reciprocal of the equivalent focal lengths in millimeters of said groups.Join the waitlist — get patent alerts
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