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 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 includes in order from an object side, a positive first unit, one or two second units including a negative lens unit closest to the image side, and monotonously moved to the image side for zooming to a telephoto end, one or two third units including a negative lens unit closest to the object side, and moved for zooming, and a positive fourth unit disposed closest to the image side, in which the first unit includes, in order from the object side, a negative subunit, a positive subunit moved for focusing, and a positive subunit, and a focal length of the first unit, a composite focal length at the telephoto end of the second unit, a maximum moving amount for zooming of the lens unit included in the second unit, and a maximum Abbe number of the negative lens included in the second unit are properly set.

Provided is a zoom lens consisting of, in order from an object side to an image side: a positive front lens unit configured not to move for zooming; a plurality of magnification-varying lens units including two magnification-varying lens units having negative refractive powers configured to move for zooming; and a positive rear lens unit configured not to move for zooming, in which a focal length of the front lens unit, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the object side in the plurality of magnification-varying lens units, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the image side in the plurality of magnification-varying lens units, and a focal length of the rear lens unit are suitably set.

Provided is a zoom lens consisting of, in order from an object side to an image side: a positive front lens unit configured not to move for zooming; a plurality of magnification-varying lens units including two magnification-varying lens units having negative refractive powers configured to move for zooming; and a positive rear lens unit configured not to move for zooming, in which a focal length of the front lens unit, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the object side in the plurality of magnification-varying lens units, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the image side in the plurality of magnification-varying lens units, and a focal length of the rear lens unit are suitably set.

A lens module is provided, including: a lens barrel including first and second barrel walls; and a set of lenses received in the lens barrel and including at least a first lens and a second lens arranged from an object side to an image side. The first lens includes a first optical portion and a first peripheral portion surrounding the first optical portion. A surface of the first barrel wall close to the image side includes a first planar surface extending horizontally towards an optical axis from a position where the first barrel wall is connected to the second barrel wall; a first oblique surface extending obliquely from the first planar surface towards the optical axis and towards the image side; and a second planar surface extending horizontally from the first oblique surface towards the optical axis.

A lens module is provided, including: a lens barrel including first and second barrel walls; and a set of lenses received in the lens barrel and including at least a first lens and a second lens arranged from an object side to an image side. The first lens includes a first optical portion and a first peripheral portion surrounding the first optical portion. A surface of the first barrel wall close to the image side includes a first planar surface extending horizontally towards an optical axis from a position where the first barrel wall is connected to the second barrel wall; a first oblique surface extending obliquely from the first planar surface towards the optical axis and towards the image side; and a second planar surface extending horizontally from the first oblique surface towards the optical axis.

A zoom optical system comprises, in order from an object: a first lens group (G1) having positive refractive power; a second lens group (G2) having negative refractive power; and a subsequent group (GR) including at least one lens group. Upon zooming, distances between the first lens group (G1) and the second lens group (G2) and between the second lens group (G2) and the subsequent group (GR) change. The subsequent group (GR) comprises a focusing group (Gfc) having negative refractive power for focusing. The first lens group (G1) comprises a 1-1st lens that has positive refractive power and is disposed closest to the object. A following conditional expression is satisfied:

0.20<f1/fR<0.85 where, f1 denotes a focal length of the first lens group, and fR denotes a focal length of a lens component, in the subsequent group, closest to an image surface.

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 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.