Patent US4595264A successfully refreshed from Google Patents.
US4595264A
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US
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Lens system for optical recording type disks
Assignee: Olympus Corp
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Filing: 1983-09-07
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Granted: 1986-06-17
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Expires: 2003-09-07
Abstract
Abstract A lens system for optical recording type disks comprising a first and second lenses wherein the first lens is a positive lens and the second lens is a positive lens, the lens system being arranged that at least one of the exit surface of the first lens and respective surfaces of the second lens is formed as an aspherical surface, the lens system being small in size and light in weight and having a long working distance and favorably corrected aberrations.
Inventors
- 👤 Toru Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:42
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/24; G02B27/00; G02B27/0025; G11; G11B; G11B7/00; G11B7/12; G11B7/135; G11B7/1372; G11B7/1374; G11B7/1392; G11B7/13922; G11B2007/13727
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
242 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged such that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens, and the surface on the exit side of said second lens is formed as an aspherical surface arranged such that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the exit side of said first lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2) and (3) shown below: ##EQU2## 0.05<E.sub.2 f.sup.3 <0.25 (2)
Claim 2
Dependent Claim
242 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged such that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens, and the surface on the exit side of said second lens is formed as an aspherical surface arranged such that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the exit side of said first lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2) and (3) shown below: ##EQU2## 0.05<E.sub.2 f.sup.3 <0.25 (2)
Claim 3
Dependent Claim
28 words
-0. 05<F 2 f 5 <0.1 (3) where, reference symbols E 2 , F 2 , G 2 , . . . respectively represent coefficients of aspherical surface.
Claim 4
Dependent Claim
28 words
-0. 05<F 2 f 5 <0.1 (3) where, reference symbols E 2 , F 2 , G 2 , . . . respectively represent coefficients of aspherical surface.
Claim 5
Dependent Claim
34 words
A lens system for optical recording type disks according to claim 1 further fulfilling the condition (4) shown below: 0.05<d.sub.3 /f<0.7 (4) where, reference symbol d 3 represents the thickness of the second lens.
Claim 6
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1 in which said lens system has the following numerical data: r 1 =1.0371 d 1 =0.2156, n 1 =1.51032 r 2 =18.2580 (aspherical surface) d 2 =0.2197 r 3 =0.6183 d 3 =0.3607, n 2 =1.51032 r 4 =1.8945 f=1, NA=0.47, Σd=0.796, WD=0.3774, E 2 =0.099487, F 2 =0 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 7
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =0.8404 d 1 =0.2391, n 1 =1.51032 r 2 =7.4418 (aspherical surface) d 2 =0.0652 r 3 =0.7012 d 3 =0.2609, n 2 =1.51032 r 4 =1.9152 f=1, NA=0.47, Σd=0.5652, WD=0.4894, E 2 =0.16421, F 2 =0.0084095 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 8
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =1.0979 d 1 =0.2858, n 1 =1.4592 r 2 =-7.6196 (aspherical data) d 2 =0.2083 r 3 =0.5486 d 3 =0.2925, n 2 =1.48224 r 4 =1.4518 f=1, NA=0.47, Σd=0.7866, WD=0.4084, E 2 =0.11823, F 2 =-0.016221 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 9
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =0.8196 d 1 =0.2017, n 1 =1.76466 r 2 =3.0950 (aspherical surface) d 2 =0.2244 r 3 =1.9893 d 3 =0.2840, n 2 =1.76466 r 4 =-76.0539 f=1, NA=0.47, Σd=0.7101 WD=0.3984, E 2 =0.19631, F 2 =0.031359 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 10
Dependent Claim
125 words
A lens system for optical recording type disks accroding to claim 1, in which said lens system has the following numerical data: r 1 =1.1067 d 1 =0.2846, n 1 =1.74289 r 2 =2.6991 (aspherical surface) d 2 =0.1567 r 3 =0.6455 d 3 =0.2839, n 2 =1.51032 r 4 =4.1012 f=1, NA=0.47, Σd=0.7252, WD=0.4454, E 2 =0.091788, F 2 =0.053379 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 11
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =1.3173 d 1 =0.2681, n 1 =1.89458 r 2 =2.0058 (aspherical surface) d 2 =0.1400 r 3 =0.7527 d 3 =0.2600, n 2 =1.89458 r 4 =2.0177 f=1, NA=0.47, Σd=0.6681 WD=0.5114, E 2 =0.053793, F 2 =0.042449 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 mn.
Claim 12
Dependent Claim
125 words
A lnes system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =1.2058 d 1 =0.2581, n 1 =1.74289 r 2 =2.1379 (aspherical surface) d 2 =0.1410 r 3 =0.7386 d 3 =0.2531, n 2 =1.76466 r 4 =2.6918 f=1, NA=0.47, Σd=0.6521 WD=0.5194, E 2 =0.080637, F 2 =0.065945 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 13
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 1, in which said lens system has the following numerical data: r 1 =0.9850 d 1 =0.2641, n 1 =1.51032 r 2 =8.6784 (aspherical surface) d 2 =0.1547 r 3 =0.6303 d 3 =0.3221, n 2 =1.48224 r 4 =2.7315 f=1, NA=0.47, Σd=0.7409 WD=0.4224, E 2 =0.13141, F 2 =0.019491 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 14
Dependent Claim
240 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens, or the surface on the exit side of said second lens is formed as an aspherical surface arranged that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where, reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the entrance side of said second lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2') and (3') shown below: ##EQU3## -0.6<E.sub.3 f.sup.3 <-0.2 (2')
Claim 15
Dependent Claim
240 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens, or the surface on the exit side of said second lens is formed as an aspherical surface arranged that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where, reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the entrance side of said second lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2') and (3') shown below: ##EQU3## -0.6<E.sub.3 f.sup.3 <-0.2 (2')
Claim 16
Dependent Claim
28 words
-1. 2<F 3 f 5 <0 (3') where, reference symbols E 3 , F 3 , G 3 , . . . respectively represent coefficients of aspherical surface.
Claim 17
Dependent Claim
28 words
-1. 2<F 3 f 5 <0 (3') where, reference symbols E 3 , F 3 , G 3 , . . . respectively represent coefficients of aspherical surface.
Claim 18
Dependent Claim
34 words
A lens system for optical recording type disks according to claim 11 further fulfilling the condition (4) shown below: 0.05<d.sub.3 /f<0.7 (4) where, reference symbol d 3 represents the thickness of the second lens.
Claim 19
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 11, in which said lens system has the following numerical data: r 1 =0.6919 d 1 =0.2283, n 1 =1.46544 r 2 =1.6766 d 2 =0.012 r 3 =0.8735 (aspherical surface) d 3 =0.4336, n 2 =1.45920 r 4 =-2.6614 f=1, NA=0.47, Σd=0.6739, WD=0.4494, E 3 =-0.47326, F 3 =-1.0037 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 20
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 11, in which said lens system has the following numerical data: r 1 =0.7814 d 1 =0.1582, n 1 1.89502 r 2 =1.5206 d 2 =0.1525 r 3 =1.7039 (aspherical surface) d 3 =0.5090, n 2 =1.89502 r 4 =12.2083 f=1, NA=0.47, Σd=0.8196, WD=0.3564, E 3 =-0.25373, F 3 =-0.040533 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 21
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 11, in which said lens system has the following numerical data: r 1 =0.7382 d 1 =0.1085, n 1 =1.65861 r 2 =1.5773 d 2 =0.1344 r 3 =1.2716 (aspherical surface) d 3 =0.5357, n 2 =1.67405 r 4 =-10.1953 f=1, NA=0.47, Σd=0.7786, WD=0.3914, E 3 =-0.2937, F 3 =-0.2420 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 22
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 11, in which said lens system has the following numerical data: r 1 =0.7578 d 1 =0.1002, n 1 =1.65861 r 2 =1.2868 d 2 =0.0887 r 3 =1.0779 (aspherical surface) d 3 =0.5549, n 2 =1.59253 r 4 =-3.1499 f=1, NA=0.47, Σd=0.7438, WD=0.4294, E 3 =-0.3074, F 3 =-0.3873 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 23
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 11, in which said lens system has the following numerical data: r 1 =0.6462 d 1 =0.0809, n 1 =1.57157 r 2 =0.9235 d 2 =0.1291 r 3 =0.9367 (aspherical surface) d 3 =0.4639, n 2 =1.59253 r 4 =-3.1019 f=1, NA=0.47, Σd=0.6739, WD=0.4864, E 3 =-0.4077, F 3 =-0.7598 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength α=800 nm.
Claim 24
Dependent Claim
240 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens or the surface on the exit side of said second lens is formed as an aspherical surface arranged that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where, reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the exit side of said second lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2") and (3") shown below: ##EQU4## 0.1<E.sub.4 f.sup.3 <0.5 (2")
Claim 25
Dependent Claim
240 words
A lens system for optical recording type disks comprising first and second lenses wherein said first lens is a positive lens and said second lens is a positive lens, said lens system being arranged that at least one of the surfaces, including the surface on the exit side of said first lens, the surface on the entrance side of said second lens or the surface on the exit side of said second lens is formed as an aspherical surface arranged that the vertex portion thereof is approximated by a spherical surface, said lens system being arranged to fulfill the condition (1) shown below: 0.4<Σd/f<0.9 (1) where, reference symbol f represents the focal length of the lens system as a whole and reference symbol Σd represents the overall length of the lens system, and in which the surface on the exit side of said second lens is formed as an aspherical surface expressed by the formula of aspherical surface shown below wherein reference symbol r represents the radius of curvature of said vertex portion of said aspherical surface, reference symbol x represents the distance from an arbitrary point on said aspherical surface to the tangential plane which is tangential to said surface at the vertex thereof, and reference symbol y represents the distance from said arbitrary point to the optical axis, said lens system being arranged to further fulfill the conditions (2") and (3") shown below: ##EQU4## 0.1<E.sub.4 f.sup.3 <0.5 (2")
Claim 26
Dependent Claim
28 words
-0. 1<F 4 f 5 <0.1 (3") where, reference symbols E 4 , F 4 , G 4 , . . . respectively represent coefficients of aspherical surface.
Claim 27
Dependent Claim
28 words
-0. 1<F 4 f 5 <0.1 (3") where, reference symbols E 4 , F 4 , G 4 , . . . respectively represent coefficients of aspherical surface.
Claim 28
Dependent Claim
34 words
A lens system for optical recording type disks according to claim 18 further fulfilling the condition (4) shown below: 0.05<d.sub.3 /f<0.7 (4) where, reference symbol d 3 represents the thickness of the second lens.
Claim 29
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 18, in which said lens system has the following numerical data: r 1 =1.0065 d 1 =0.2681, n 1 =1.76466 r 2 =1.9150 d 2 =0.1807 r 3 =0.6672 d 3 =0.2033, n 2 =1.89502 r 4 =1.1777 (aspherical surface) f=1, NA=0.47, Σd=0.6521, WD=0.4754, E 4 =0.17478, F 4 =0 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 30
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 18, in which said lens system has the following numerical data: r 1 =0.9043 d 1 =0.2594, n 1 =1.76466 r 2 =1.6084 d 2 =0.1666 r 3 =0.6417 d 3 =0.2260, n 2 =1.74289 r 4 =1.2946 (aspherical surface) f=1, NA=0.47, Σd=0.652, WD=0.4524, E 4 =0.36266, F 4 =0 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 31
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 18, in which said lens system has the following numerical data: r 1 =0.9077 d 1 =0.2596, n 1 =1.4592 r 2 =13.3065 d 2 =0.1824 r 3 =0.5202 d 3 =0.12, n 2 =1.48224 r 4 =1.4664 (aspherical surface) f=1, NA=0.47, Σd=0.562, WD=0.5484, E 4 =0.3691, F 4 =0.05116 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of responsive lenses for the wavelength λ=800 nm.
Claim 32
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 18, in which said lens system has the following numeral data: r 1 =0.9647 d 1 =0.2619, n 1 =1.57157 r 2 =4.0121 d 2 =0.1863 r 3 =0.5544 d 3 =0.2210, n 2 =1.57157 r 4 =1.1868 (aspherical surface) f=1, NA=0.47, Σd=0.6693 WD=0.4564, E 4 =0.39454, F 4 =0.050261 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively respresent refractive indices of respective lenses for the wavelength λ=800 nm.
Claim 33
Dependent Claim
125 words
A lens system for optical recording type disks according to claim 18, in which said lens system has the following numerical data: r 1 =0.9754 d 1 =0.3806, n 1 =1.51032 r 2 =6.2192 d 2 =0.2676 r 3 =0.4665 d 3 =0.1280, n 2 =1.51032 r 4 =1.2122 (aspherical surface) f=1, NA=0.47, Σd=0.776, WD=0.4564, E 4 =0.4752, F 4 =0.05427 where, reference symbols r 1 , r 2 , r 3 and r 4 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 , d 2 and d 3 respectively represent thicknesses of respective lenses and airspace between respective lenses, and reference symbols n 1 and n 2 respectively represent refractive indices of respective lenses for the wavelength λ=800 nm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-16 | 1989-12-16 | 1990-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-16 | 1993-12-16 | 1994-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-16 | 1997-12-16 | 1998-06-17 | $7700.00 | Window Closed / Lapsed |