Zoom lens system for maintaining two pairs of conjugate planes fixed

Claim 2

A variable-magnification zoom lens system comprising three lens components each of which is arraNged to be movable and movable relative to the other two and displacement means for simultaneously moving the lens components, the means for moving the lens components being arranged so that, as the magnification M of the zoom system is changed, the relations K M/L-1/ML and DK PK+ (M-1)2/M are substantially satisfied to maintain two pairs of conjugate planes fixed as the magnification is varied, one pair of conjugate planes forming the object and image planes, and the entrance and exit pupils lying at or near the other pair of conjugate planes, where L is the distance from the fixed object plane to the fixed entrance pupil plane, L'' is the distance from the fixed image plane to the fixed exit pupil plane, P is distance from the object plane to the image plane, K is the equivalent power of the zoom system when the magnification is M, D is the distance between the principal planes of the zoom system when the magnification is M.

Claim 3

A variable-magnification zoom lens system comprising at least three lens components of which three are movable and movable relative to one another, and means for moving all three movable lens components simultaneously, the front and rear movable components being of positive power and equal focal length and the center component being of negative power, the mean for moving the lens components being arranged to move all three simultaneously such that

Claim 4

A variable-magnification zoom lens system comprising at least three lens components of which three are movable and movable relative to one another, and means for moving all three movable lens components simultaneously, the front and rear movable components being of positive power and equal focal length and the center component being of negative power, the mean for moving the lens components being arranged to move all three simultaneously such that

Claim 5

A variable-magnification zoom lens system comprising three lens components, each of which is movable, with means for simultaneously moving the lens components, the means for moving the lens components being arranged so that, as the magnification M of the zoom system is changed, the relations K M/L''-1/ML and DK PK+ (M-1)2/M are substantially satisfied to maintain two pairs of conjugate planes fixed as the magnification is varied, one pair of conjugate planes forming the object and image planes and exit pupils lying at or near the other pair of conjugate planes, where L is the distance from the fixed object plane to the fixed entrance pupil plane, L'' is the distance from the fixed image plane to the fixed exit pupil plane, P is the distance from the object plane to the image plane, K is the equivalent power of the zoom system when the magnification is M, D is the distance between the principal planes of the zoom system when the magnification is M, whereby the interlens spacings d12 and d23 between the first and second lens components and between the second and third lens components respectively are determinable from the equations K K1+K2+K3-dK1K3- (d12K1+d23K3)K2+d12 d23K1K2K3 and DK -d2K1K3-(d122K1+d232K3)K2 +dd12d23K1K2K3 where K1K2 and K3 are the power of the first, second and third lens components respectively, and d d12+d23.

Claim 6

A variable-magnification zoom lens system comprising three lens components, each of which is movable, with means for simultaneously moving the lens components, the means for moving the lens components being arranged so that, as the magnification M of the zoom system is changed, the relations K M/L''-1/ML and DK PK+ (M-1)2/M are substantially satisfied to maintain two pairs of conjugate planes fixed as the magnification is varied, one pair of conjugate planes forming the object and image planes and exit pupils lying at or near the other pair of conjugate planes, where L is the distance from the fixed object plane to the fixed entrance pupil plane, L'' is the distance from the fixed image plane to the fixed exit pupil plane, P is the distance from the object plane to the image plane, K is the equivalent power of the zoom system when the magnification is M, D is the distance between the principal planes of the zoom system when the magnification is M, whereby the interlens spacings d12 and d23 between the first and second lens components and between the second and third lens components respectively are determinable from the equations K K1+K2+K3-dK1K3- (d12K1+d23K3)K2+d12 d23K1K2K3 and DK -d2K1K3-(d122K1+d232K3)K2 +dd12d23K1K2K3 where K1K2 and K3 are the power of the first, second and third lens components respectively, and d d12+d23.

Claim 7

A variable-magnification zoom lens system comprising a plurality of lens components with means for simultaneously moving three lens components the means for moving the lens components being arranged so that, as the magnification M of the zoom system is changed, the relations K M/L''-1/ML and DK PK+ (M-1)2/M are substantially satisfied to maintain two pairs of conjugate planes fixed as the magnification is varied, one pair of conjugate planes forming the object and image planes and the other pair of conjugate planes being the entrance and exit pupil planes, where L is the distance from the fixed object plane to the fixed entrance pupil plane, L'' is the distance from the fixed image plane to the fixed exit pupil plane, P is distance from the object plane to the image plane, K is the equivalent power of the zoom system when the magnification is M, D is the distance between the principal planes of the zoom system when the magnification is M, whereby the interlens spacings d12 and d23 between the first and second lens components and between the second and third lens components respectively are determinable from the equations K K1+K2+K3-dK1K3-(d12K1+d23K3)K2+d12d23K1K2K3 and DK -d2K1K3-(d122K3)K2+dd12d23K1K23 where K1, K2 and K3 are the powers of the first, second and third lens components respectively, and d d12+d23, one said means for moving the lens being arranged so that the distance l1 of the first lens from the fixed object plane is given by the relation l1 (1/M-1)(F- gamma where gamma is the distance of the first principal plane of the system from the fist lens and where F 1/K.

Claim 8

A variable-magnification zoom lens system comprising a plurality of lens components with means for simultaneously moving three lens components the means for moving the lens components being arranged so that, as the magnification M of the zoom system is changed, the relations K M/L''-1/ML and DK PK+ (M-1)2/M are substantially satisfied to maintain two pairs of conjugate planes fixed as the magnification is varied, one pair of conjugate planes forming the object and image planes and the other pair of conjugate planes being the entrance and exit pupil planes, where L is the distance from the fixed object plane to the fixed entrance pupil plane, L'' is the distance from the fixed image plane to the fixed exit pupil plane, P is distance from the object plane to the image plane, K is the equivalent power of the zoom system when the magnification is M, D is the distance between the principal planes of the zoom system when the magnification is M, whereby the interlens spacings d12 and d23 between the first and second lens components and between the second and third lens components respectively are determinable from the equations K K1+K2+K3-dK1K3-(d12K1+d23K3)K2+d12d23K1K2K3 and DK -d2K1K3-(d122K3)K2+dd12d23K1K23 where K1, K2 and K3 are the powers of the first, second and third lens components respectively, and d d12+d23, one said means for moving the lens being arranged so that the distance l1 of the first lens from the fixed object plane is given by the relation l1 (1/M-1)(F- gamma where gamma is the distance of the first principal plane of the system from the fist lens and where F 1/K.