A lens assembly includes a first lens group, a second lens group, and a third lens group, all of which are arranged in order from a first side to a second side along an optical axis. The first lens group is with positive refractive power. The second lens group is with positive refractive power. The third lens group is with positive refractive power. The first lens group is fixed, the second lens group can move along the optical axis, and the third lens group can move along the optical axis, so that the lens assembly is zoomed from a wide-angle end to a telephoto end to change an effective focal length.

A zoom lens consists of, in order from the object side, a first lens group that has a positive refractive power, a middle group that includes a plurality of lens groups in which the spacings between adjacent lens groups change during zooming, and the final lens group. The focusing group that moves during focusing is disposed in the middle group. The zoom lens satisfies predetermined conditional expressions.

Provided is a small zoom lens having a high zoom ratio and easily designed to achieve favorable optical properties in an entire zooming range. A zoom lens includes, in order from object side to image side, a positive first unit, a negative second unit, an aperture stop, and a rear group including multiple units. Intervals between the adjacent units are changed during zooming. In the rear group, a positive lens unit is arranged on the most image side, and a negative lens unit is on the object side of the positive lens unit. The aperture stop not moving for zooming, but the second unit and the negative lens unit moving during zooming. Focal lengths of the second unit and the positive and negative lens units, and movement amounts of the second and negative lens units, respectively, during zooming from wide angle end to telephoto end are appropriately set.

A zoom lens system includes a first lens group; a second lens group; and a subsequent lens group arranged in that order from the object side. The second lens group consists of a second lens group-a, a second lens group-b, and a second lens group-c arranged in that order from the object side. A distance between the first lens group and the second lens group increases and a distance between the second lens group and the subsequent lens group decreases during a change in magnification from a short focal length end to a long focal length end. During a change in focus from infinity to a short distance, the second lens group-b is movable to the image side, and a distance between the second lens group-a and the second lens group-b and a distance between the second lens group-b and the second lens group-c are changeable.

A first lens unit and a third lens unit are constituted by a lens which is rotationally symmetrical with respect to an optical axis and are disposed on the same optical axis, a first freeform-curved surface lens and a second freeform-curved surface lens have the same shape and are disposed to be rotated at 180 degrees with respect to the optical axis, the first freeform-curved surface lens and the second freeform-curved surface lens are movable in a Y-axis direction when the optical axes of the first lens unit and the third lens unit are set to be a Z-axis, an axis perpendicular to the Z-axis on an image surface is set to be a Y-axis, and an axis perpendicular to the Y-axis and the Z-axis on the image surface is set to be an X-axis, a refractive power of the second lens unit is variable due to the first freeform-curved surface lens and the second freeform-curved surface lens moving in opposite directions, and the first freeform-curved surface lens and the second freeform-curved surface lens are moved in the Y-axis direction in association with movement of some of lens groups constituting the first lens unit and the third lens unit when positional states of the lenses are changed from a wide angle end state in which a focal distance is shortest to a telephoto end state in which a focal distance is longest.

An imaging module (1000), an imaging method, and an electronic device (2000) are provided. The imaging module (1000) includes a zoom lens (100) and a photosensitive element (402). The zoom lens (100) includes a first lens group (10), a second lens group (20), and a third lens group (30). The imaging method include: during switching from a long focus to a short focus, controlling the second lens group (20) and the photosensitive element (402) to move towards an object side; and during switching from the short focus to the long focus, controlling the second lens group (20) and the photosensitive element (402) to move towards an image side.

A lens assembly includes a first lens group, a second lens group, and a third lens group, all of which are arranged in order from an object side to an image side along an optical axis. The first lens group is with positive refractive power and includes at least four lenses, among which the lens closest to the object side includes a convex surface facing the object side, and the lens closest to the image side includes a convex surface facing the image side. The second lens group is with negative refractive power and includes a 2-1 lens and a 2-2 lens, wherein the 2-2 lens includes a convex surface facing the image side. The third lens group is with negative refractive power and includes a 3-1 lens, wherein the 3-1 lens is a meniscus lens with negative refractive power.

The zoom lens consists of, in order from an object side: a first lens group that has a positive refractive power; a middle group that includes a plurality of lens groups each moving by changing a spacing with an adjacent lens group during zooming; and a final lens group that remains stationary during zooming and has a positive refractive power. Among the plurality of lens groups that move during zooming in the middle group, an image side movable lens group, which is a lens group disposed closest to the image side, has a negative refractive power.

A zoom lens system includes a first lens group; a second lens group; and a subsequent lens group arranged in that order from the object side. The second lens group consists of a second lens group-a, a second lens group-b, and a second lens group-c arranged in that order from the object side. A distance between the first lens group and the second lens group increases and a distance between the second lens group and the subsequent lens group decreases during a change in magnification from a short focal length end to a long focal length end. During a change in focus from infinity to a short distance, the second lens group-b is movable to the image side, and a distance between the second lens group-a and the second lens group-b and a distance between the second lens group-b and the second lens group-c are changeable.

Provided is a zoom lens including a plurality of lens units in which intervals between adjacent lens units are changed during zooming. The plurality of lens units consist of, in order from object side to image side, a positive first lens unit, a negative second lens unit and a rear lens group including at least one lens unit. A minimum F-number of zoom lens during zooming from wide angle end to telephoto end, an interval, at wide angle end, between a lens surface on object side of a lens arranged closest to object side of rear lens group and a lens surface on image side of a lens arranged closest to image side of rear lens group, a total lens length of zoom lens at wide angle end, and the widest lens interval at wide angle end among lens intervals included in rear lens group are each appropriately set.