The zoom lens consists of, in order from the object side, a first lens group that has a negative refractive power; a second lens group that has a positive refractive power; a third lens group that has a negative refractive power; and a fourth lens group that has a positive refractive power. During zooming, in each lens group, distances between the adjacent groups in the direction of the optical axis are changed. The first lens group consists of, in order from the object side, a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power. The third lens group consists of a negative lens. During focusing, only the third lens group moves along the optical axis. The zoom lens satisfies predetermined conditional expressions.

A camera module includes a first lens group; a first optical path folding unit; a second lens group; and a second optical path folding unit. The first lens group, the first optical path folding unit, the second lens group, and the second optical path folding unit are sequentially disposed from an object side of the first lens group toward an imaging plane of the camera module. The first optical path folding unit includes a first fixed reflective member and a first movable reflective member configured to vary a length of an optical path between the first lens group and the second lens group, and the second optical path folding unit includes a second fixed reflective member and a second movable reflective member configured to vary a length of an optical path between the second lens group and an imaging plane.

The anamorphic objective lens systems (100LS) and methods for forming a set of anamorphic objective lens assemblies (100(i)) having different focal lengths (FLY) and that utilize a front anamorphic section (20) and a set of two or more non-anamorphic sections (50(i)). The non-anamorphic sections are optically matched to the front anamorphic section and their front ends (52) are configured to be easily attached to and detached from the back end (24) of the front anamorphic section to create the anamorphic objective lens assemblies having the different focal lengths. Because the anamorphic objective lens system uses only a single front anamorphic section and multiple non-anamorphic attachments, the cost of having multiple anamorphic objective lens assemblies is substantially reduced as compared to using individual anamorphic objective lenses for each of the desired focal lengths.

A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a plurality of lens groups including at least two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, at a position closer to the reduction side than the intermediate image. Among the plurality of lens groups, a final lens group closest to the reduction side has a positive refractive power, and remains stationary with respect to the reduction side imaging plane during zooming. The zoom lens satisfies predetermined conditional expressions (1) and (2) about the focal lengths of the movable lens groups.

The invention relates to an optical system (1) comprising a solid lens barrel (2) for optical elements (3), wherein the lens barrel (2) extends along an optical axis (100) of the optical system (100), the lens barrel (2) holding a plurality of optical elements (3), the plurality comprising a lens system (5), comprising at least one solid lens (53), and a first lens (6) having an adjustable focal length, wherein the first lens (6) comprises a container (62) filled with a transparent fluid, wherein the container (62) comprises an elastically deformable and transparent membrane (61) facing a transparent bottom portion (67) of the container (62), wherein the lens barrel (2) has a first and a second opening (22, 22′) facing along the optical axis (100), wherein the first and/or the second opening (22, 22′) is configured to receive the lens system (5), wherein the lens barrel (2) has a first slot (24) extending perpendicular to the optical axis (100), wherein the first lens (6) is inserted through the first slot (24) perpendicular the optical axis (100) into the lens barrel (2). The invention further relates to method of assembly of such an optical system (1).

The disclosure provides a combined zoom dual-camera lens assembly, which includes a first lens group and a second lens group, wherein a field of view of the second lens group is larger than a field of view of the first lens group, and a thickness of the second lens group is smaller than a thickness of the first lens group; and a total effective focal length f.sub.T of the first lens group and a total effective focal length f.sub.W of the second lens group meet f.sub.T/f.sub.W>9.00.

Provided is an optical apparatus including: a first optical element configured to be movable in an optical axis direction; a second optical element configured to be movable in the optical axis direction; a first elastic member configured to bias the first optical element in the optical axis direction; and a second elastic member configured to bias the first optical element and the second optical element in the optical axis direction due to reduction in distance between the first optical element and the second optical element, wherein the second elastic member is configured to bias the first optical element, due to the reduction, in a direction in which the first elastic member biases the first optical element.

An optical lens assembly includes: a diaphragm, a zoom lens group, a light deflecting assembly and a compensating lens group sequentially arranged along an optical axis and from an object side to an imaging plane. The optical axis comprises a first optical axis segment between the diaphragm and the light deflecting assembly, and a second optical axis segment between the light deflecting assembly and the compensating lens group. The zoom lens group is located on the first optical axis segment, and the first optical axis segment is different from the second optical axis segment. The optical lens assembly may be incorporated in a camera unit and an electronic device.

In one aspect, a light-mixing system is disclosed, which includes a light pipe having an input surface configured for receiving light from a light source, a light-mixing segment optically coupled to the input surface, and an output surface optically coupled to said light-mixing segment through which light exits the light pipe. A putative vector normal to at least one of the input or the output surface forms a non-zero angle relative to a longitudinal axis of the light-mixing segment. In some embodiments, the non-zero angle can be, for example, about 90 degrees.

The zoom lens consists of, in order from the object side, a first lens group that has a negative refractive power; a second lens group that has a positive refractive power; a third lens group that has a negative refractive power; and a fourth lens group that has a positive refractive power. During zooming, in each lens group, distances between the adjacent groups in the direction of the optical axis are changed. The first lens group consists of, in order from the object side, a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power. The third lens group consists of a negative lens. During focusing, only the third lens group moves along the optical axis. The zoom lens satisfies predetermined conditional expressions.