A zoom lens including from object side: a positive first unit; at least one negative unit moving toward image side for zooming from wide to telephoto; and at least two positive units each moving toward object side for the zooming, in which the positive first unit includes a biconcave lens closest to object side, in which an N unit is one of the at least one negative unit and having largest amount of movement during the zooming, and P unit is one of the at least two positive units having largest amount of movement during the zooming; in which focal lengths of the first lens unit, of the zoom lens at wide end and telephoto end, a difference between distances from the N unit to image plane at telephoto end and at wide end and a distance from the P unit to image plane at telephoto end are appropriately set.

A lens attachment module is configured for coupling with a zoom module of a finite conjugate optical assembly. The lens attachment module includes a lens assembly that has a positive focal length, and exhibits a pupil size of between 16 and 25 mm and a pupil depth greater than 50 mm.

A lens attachment module is configured for coupling with a zoom module of a finite conjugate optical assembly. The lens attachment module includes a lens assembly that has a positive focal length, and exhibits a pupil size of between 16 and 25 mm and a pupil depth greater than 50 mm.

Digital cameras comprising a lens assembly comprising N lens elements L.sub.1-L.sub.N starting with L.sub.1 on an object side, wherein N is ≥4, an image sensor having a sensor diagonal S.sub.D, and a pop-out mechanism that controls a largest air-gap d between two consecutive lens elements within lens elements L.sub.1 and L.sub.N to bring the camera to an operative pop-out state and a collapsed state, wherein the lens assembly has a total track length TTL in the operative pop-out state and a collapsed total track length cTTL in the collapsed state, wherein S.sub.D is in the range of 7-20 mm and wherein cTTL/S.sub.D<0.6.

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.

The zoom lens includes a positive first lens group, a negative second lens group, a positive third lens group, a negative fourth lens group, a negative fifth lens group, and a positive sixth lens group in order from an object side. All distances between adjacent lens groups change during zooming. The first lens group consists of a negative lens, a positive lens, and a positive lens in order from the object side. Only the fourth lens group moves to an image side during focusing from a long range to a short range. Conditional Expression is related to lateral magnification of the fourth lens group and a lateral magnification of the sixth lens group is satisfied.

An example variable focusing lens apparatus, as well as example methods for assembling and operating the example variable focusing lens apparatus, is provided. The example variable focusing lens apparatus includes a rear pair of coil elements powered by a rear coil current, a front pair of coil elements positioned in front of the rear pair of coil elements and powered by a front coil current, and a barrel lens assembly comprising a top magnetic element secured on a top portion of the barrel lens assembly and a bottom magnetic element secured on a bottom portion of the barrel lens assembly. In some examples, the barrel lens assembly is moveable to a plurality of barrel lens assembly positions corresponding to a plurality of current differential ratios associated with the rear coil current and the front coil current.

An example variable focusing lens apparatus, as well as example methods for assembling and operating the example variable focusing lens apparatus, is provided. The example variable focusing lens apparatus includes a rear pair of coil elements powered by a rear coil current, a front pair of coil elements positioned in front of the rear pair of coil elements and powered by a front coil current, and a barrel lens assembly comprising a top magnetic element secured on a top portion of the barrel lens assembly and a bottom magnetic element secured on a bottom portion of the barrel lens assembly. In some examples, the barrel lens assembly is moveable to a plurality of barrel lens assembly positions corresponding to a plurality of current differential ratios associated with the rear coil current and the front coil current.

A rear adapter module for a finite conjugate optical assembly and camera is configured to couple with a core zoom module. A lens assembly of the rear adapter module includes three or more lens elements and has a positive focal length. The lens assembly exhibits a pupil size of between 16 and 25 mm and a pupil depth greater than 50 mm.