Optical system for the magnification varying portion of an ultra-telephoto type zoom lens

Claim 2

An optical system for an ultra-telephoto type zoom lens system comprising a magnification varying portion including a first convergence lens group, a second divergence lens group, a third convergence lens group and a relay lens group disposed in the named order, said first, second and third lens groups forming an afocal magnification varying system, said second and third groups being axially differently movable in the same direction, and said relay lens group forming a telephoto system having a positive Petzval sum; said first group including two components, of which the first component is a single biconvex lens, and the second component consists of a biconcave lens, a biconcave lens and a convex meniscus lens, these three lenses cemented together; said second group including three components of which the first component consists of a biconvex lens and a biconcave lens cemented together, the second and third components are single biconcave lenses, respectively; said third group including two components of which the first component consists of two meniscus lenses cemented together and the curvature of the cemented surface being concave to the object side, and the second component consists of a biconvex lens and a concave meniscus lens cemented together(; and said relay lens group including two portions of which the first portion comprises two components, the first component thereof being a single biconvex lens, and the second component beiNg a biconvex and biconcave lenses cemented together, and the second portion comprises two components, the first component thereof being a single biconvex lens and the second component being a biconcave and biconvex lenses cemented together) .

Claim 3

An optical system according to claim 1, possessing the following dimensions and relationships; f 180-600 mm, F/8 telephoto ratio 0.7

Claim 4

An optical system for an ultra-telephoto type zoom lens system comprising a magnification varying portion including a first convergence lens group, a second divergence lens group, a third convergence lens group and a relay lens group disposed in the named order, said first, second and third lens groups forming an afocal magnification varying system, said second and third groups being axially differently movable in the same direction and said relay lens group forming a telephoto system having a positive Petzval sum; said first group including two components, of which the first component is a single biconvex lens, and the second component consists of a biconvex lens, a biconcave lens and a convex meniscus lens, the latter two of these three lenses cemented together; said second group including three components of which the first component consists of a biconvex lens and biconcave lens cemented together, the second component consists of a biconcave and convex meniscus lens cemented together to enhance the achromatism of the second divergent group as a whole, and the third component is a single biconcave lens; said third group including two components of which the first component consists of two meniscus lenses cemented together and the curvature of cemented surface being concave to the object side, and the second component consists of a biconvex lens and a concave meniscus lens cemented together(; and said relay lens group including two portions of which the first portion comprises two components, the first component thereof being a single biconvex lens, and the second component being a biconvex, biconcave and concave meniscus lenses cemented together, and the second portion comprises two components, the first component thereof being a single biconvex lens and the second component being a biconcave and biconvex lenses cemented together) .

Claim 5

An optical system for an ultra-telephoto type zoom lens system comprising a magnification varying portion including a first convergence lens group, a second divergence lens group, a third convergence lens group and a relay lens group disposed in the named order, said first, second and third lens groups forming an afocal magnification varying system, said second and third groups being axially differently movable in the same direction and said relay lens group forming a telephoto system having a positive Petzval sum; said first group including two components, of which the first component is a single biconvex lens, and the second component consists of a biconvex lens, a biconcave lens and a convex meniscus lens, the latter two of these three lenses cemented together; said second group including three components of which the first component consists of a biconvex lens and biconcave lens cemented together, the second component consists of a biconcave and convex meniscus lens cemented together to enhance the achromatism of the second divergent group as a whole, and the third component is a single biconcave lens; said third group including two components of which the first component consists of two meniscus lenses cemented together and the curvature of cemented surface being concave to the object side, and the second component consists of a biconvex lens and a concave meniscus lens cemented together(; and said relay lens group including two portions of which the first portion comprises two components, the first component thereof being a single biconvex lens, and the second component being a biconvex, biconcave and concave meniscus lenses cemented together, and the second portion comprises two components, the first component thereof being a single biconvex lens and the second component being a biconcave and biconvex lenses cemented together) .

Claim 6

An optical system according to claim 3, possessing the following dimensions and relationships; f 360 -1200 mm, F/11 telephoto ratio 0.61

Claim 7

An optical system for an ultra-telephoto type zoom lens comprising a magnification varying portion including a first convergence lens group, a divergence lens group, and a second convergence lens group disposed in the named order from the object side of the system and having focal lengths designated, respectively, by f1, f2 and f3, and a relay lens group having a focal length designated by f4, said optical system satisfying the following numerical data wherein, r1, r2...r32 designate the radii of curvature of the successive lenses, d1, d2...d31 designate the center thickness of, or air gaps between the successive lenses, n1, n2...n20 designate the refractive indices of the lenses for d-line, and v1, v2...v20 designate the Abbe numbers of the lenses:

Claim 8

An optical system for an ultra-telephoto type zoom lens comprising a magnification varying portion including a first convergence lens group, a divergence lens group, and a second convergence lens group disposed in the named order from the object side of the system and having focal lengths designated, respectively, by f1, f2 and f3, and a relay lens group having a focal length designated by f4, said optical system satisfying the following numerical data wherein, r1, r2...r32 designate the radii of curvature of the successive lenses, d1, d2...d31 designate the center thickness of, or air gaps between the successive lenses, n1, n2...n20 designate the refractive indices of the lenses for d-line, and v1, v2...v20 designate the Abbe numbers of the lenses:

Claim 9

An optical system for an ultra-telephoto type zoom lens comprising a magnification varying portion including a first convergence lens group, a divergence lens group, and a second convergence lens group disposed in the named order from the object side of the system and having focal lengths designated, respectively, by f1, f2 and f3, and a relay lens group having a focal length designated by f4, said optical system satisfying the following numerical data wherein, r1, r2...r29 designate the radii of curvature of the successive lenses, d1, d2...d28 designate the center thicknesses of, or air gaps between the successive lenses, n1, n2...n18 designate the refractive indices of the lenses for d-line, and v1, v2...v18 designate the Abbe numbers of the lenses:

Claim 10

An optical system for an ultra-telephoto type zoom lens comprising a magnification varying portion including a first convergence lens group, a divergence lens group, and a second convergence lens group disposed in the named order from the object side of the system and having focal lengths designated, respectively, by f1, f2 and f3, and a relay lens group having a focal length designated by f4, said optical system satisfying the following numerical data wherein, r1, r2...r29 designate the radii of curvature of the successive lenses, d1, d2...d28 designate the center thicknesses of, or air gaps between the successive lenses, n1, n2...n18 designate the refractive indices of the lenses for d-line, and v1, v2...v18 designate the Abbe numbers of the lenses: