A finite conjugate optical assembly, comprising a lens with a core zoom module that includes five optical groups that are configured to exhibit at least 1.58 mm.sup.2sr of etendue at a lowest magnification position, and a ratio of highest to lowest magnification of at least 7:1, and to provide a maximum magnification of 2× or greater.

A finite conjugate lens assembly including an afocal zooming component that has five optical groups that are configured to provide a ratio of highest to lowest magnification between 5.5:1 and 16:1. A lens attachment module and rear adapter module may be disposed, respectively, on an object side and an image side of the optical assembly. The lens assembly may exhibit an approximate etendue between 0.95 and 4.65 mm.sup.2sr, and may be configured in accordance with between 6.6 MP and 32 MP image sensors.

A finite conjugate optical assembly including a core zoom module that includes five optical groups that are configured to provide a ratio of highest to lowest magnification between 5.5:1 and 16:1. A lens attachment module and rear adapter module may be disposed, respectively, on an object side and an image side of the optical assembly. The optical assembly may exhibit an approximate etendue between 0.95 and 4.65 mm.sup.2sr, and may have a magnification of 2× or more at one or more points of the zoom. The optical assembly may be configured in accordance with between 6.6 MP and 32 MP image sensors.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a plurality of zooming lens units configured to move along an optical axis in zooming and including a lens unit having a negative refractive power, and a final lens unit having a positive refractive power. A distance between each pair of adjacent lens units changes in zooming. The first lens unit includes, in order from the object side to the image side, a first subunit having a negative refractive power, a second subunit having a negative refractive power, and at least one subsequent subunit, a distance between each pair of adjacent subunits changing for focusing. The second subunit is configured to move along the optical axis for focusing. A predetermined condition is satisfied.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a plurality of lens units which move in zooming, and a final lens unit having a positive refractive power, an interval between each pair of adjacent lens units changing in zooming, the plurality of lens units including a lens unit having a negative refractive power, the first lens unit including a negative lens and a positive lens, at least a part of the first lens unit moving for focusing, the first lens unit including a negative lens made of a material satisfying inequalities defined by a refractive index, an Abbe number, and a partial dispersion ratio, and the zoom lens satifying an inequality defined by a maximum value of an Abbe number of at least one positive lens of the first lens unit.

A high etendue modular finite conjugate lens assembly has a zooming component with multiple lens groups, including four lens groups that each feature a doublet, and a lens attachment lens assembly comprising a fifth doublet, wherein the lens assembly is configured to exhibit between 0.45 and 4.65 mm.sup.2sr of etendue, and a ratio of highest to lowest magnification between 5.5:1 and 16:1, and a magnification of at least 2× at one or more points of a zoom range.

A modular finite conjugate zoom lens assembly with five lens groups each including a doublet, wherein two or three movable lens groups are disposed between a pair of static lens groups.

A zoom lens satisfies Conditional Expression (1) as follows:
−20<Twt/Twm<1,  (1)
Twt is a moving amount of the second lens group during zooming from the short focal-length end to the long focal-length end, a moving amount to the object side being indicated by a positive sign, a moving amount to an image side being indicated by a negative sign, and
Twm is a moving amount of the second lens group during zooming from the short focal-length end to an intermediate focal length, a moving amount to the image side being indicated by a negative sign,
the intermediate focal length being expressed by fm=(fw.Math.ft).sup.1/2, where fw is a focal length of a whole system at the short focal-length end, and ft is a focal length of the whole system at the long focal-length end.

A finite conjugate optical assembly, comprising a lens with a core zoom module that includes five optical groups that are configured to exhibit at least 1.58 mm.sup.2sr of etendue at a lowest magnification position, and a ratio of highest to lowest magnification of at least 7:1, and to provide a maximum magnification of 2 or greater.

A finite conjugate lens assembly with modular interchangeable components includes a zooming component that includes three independently movable lens groups that are disposed within the lens assembly between a pair of static lens groups. The lens assembly exhibits an etendue of between 0.95 and 4.65 mm.sup.2sr.