The zoom lens consists of, in order from an object side: a positive first lens group that does not move during zooming; a middle group that consists of two or more movable lens groups moving during zooming; and a subsequent group that has a lens group including a stop at a position closest to the object side. The middle group has at least two negative movable lens groups. The subsequent group includes at least one positive LA lens that satisfies predetermined conditional expressions relating to the refractive index, the Abbe number, and the partial dispersion ratio.

A zoom lens includes in order from an object side to an image side, a first lens unit having a positive refractive power; a second lens unit having a negative refractive power and configured to move for zooming; and at least one lens unit configured to move for zooming. The distance between each pair of the lens units adjacent to each other is changed for zooming. The first lens unit includes a negative lens and an Abbe number and a partial dispersion ratio of the negative lens are properly determined.

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.

Provided are an imaging apparatus, a signal processing method for an imaging apparatus, and a non-transitory computer readable recording medium storing a signal processing program for an imaging apparatus capable of capturing a high quality image with a compact configuration. An imaging lens 10A is composed of, in order from an object side, a first lens group G1 that is fixed during variable magnification, a second lens group G2 and a third lens group G3 that move during variable magnification, and a fourth lens group G4 that is fixed during variable magnification. The first lens group G1 is composed, in order from the object side, a first-a lens group G1a that is fixed during focusing, a first-b lens group G1b that moves during focusing, and a first lens group rear group G1c that is fixed during focusing. Fluctuation of an angle of view with focusing is corrected through image processing.

An optical system includes a light source, an interferometer, and a detector. The interferometer includes a scanner and a lens system disposed downstream of the scanner. The scanner is configured to direct a portion of the optical beam along one of a plurality of different directions within a scanning range. The lens system is configured to project the portion of optical beam to an imaging area defined by a field of view of the optical system, the lens system comprising a first lens, wherein an aspect of the first lens is adjustable so as to render the field of view adjustable without adjusting the scanning range of the scanner. The detector is configured to receive a reflected portion of the optical beam that reflects from an object placed within the imaging area.

An optical system includes a light source, an interferometer, and a detector. The interferometer includes a scanner and a lens system disposed downstream of the scanner. The scanner is configured to direct a portion of the optical beam along one of a plurality of different directions within a scanning range. The lens system is configured to project the portion of optical beam to an imaging area defined by a field of view of the optical system, the lens system comprising a first lens, wherein an aspect of the first lens is adjustable so as to render the field of view adjustable without adjusting the scanning range of the scanner. The detector is configured to receive a reflected portion of the optical beam that reflects from an object placed within the imaging area.

A zoom lens includes, in order from the object side, a first positive lens unit that remains unmoved for zooming, a second negative lens unit that is moved for zooming, one or two zooming lens units that is moved for zooming, and a positive rear lens unit that remains unmoved for zooming. The intervals between adjacent lens units are changed during zooming. The rear lens unit composed of a front sub lens unit within a range satisfying 0<d4a/d4<0.3, where d4 is the thickness of the rear lens unit, and d4a is the distance from the vertex of a lens closest to the object side in the rear lens unit, and a rear sub lens unit outside the range. The average Abbe numbers of convex and concave lenses in the front sub lens unit and the average partial dispersion ratio of the convex lenses are appropriately set.

The variable magnification optical system includes, in order from an object side, a positive first lens group disposed at a position closest to the object side, a variable magnification lens group which is disposed at a position closest to the object side among negative lens groups and moves during changing magnification, an intermediate group including at least one lens group, and a positive final lens group which is disposed at a position closest to the image side. The variable magnification lens group, the intermediate group, and the final lens group are continuously disposed. The variable magnification optical system includes at least one LA lens. This LA lens satisfies predetermined conditional expressions relating to a refractive index, an Abbe number, and a partial dispersion ratio, and is located from the variable magnification lens group to the intermediate group.

The zoom lens consists of, in order from the object side, a first lens group that has a positive refractive power and remains stationary during zooming, a plurality of movable lens groups that move during zooming, and a final lens group that has a positive refractive power and remains stationary during zooming. The first lens group consists of, in order from the object side, a first lens group front group that has a negative refractive power and remains stationary during focusing, a first lens group intermediate group that has a positive refractive power and moves during focusing, and a first lens group rear group that has a positive refractive power. The first lens group front group has, successively in order from a position closest to the object side, a negative meniscus lens that is concave toward the image side and a negative lens.

The zoom lens consists of, in order from the object side, a positive first lens group G1, a negative second lens group G2, a negative third lens group G3, a stop, and a positive fourth lens group G4. During zooming, the first lens group G1 and the fourth lens group G4 remain stationary, and the second lens group G2 and the third lens group G3 move. The first lens group G1 consists of, in order from the object side, a negative first lens group front group G1A that remains stationary during focusing, a positive first lens group intermediate group G1B that moves during focusing, and a positive first lens group rear group G1C that remains stationary during focusing. The following conditional expression relating to an Abbe number n1A2 of the second negative lens from the object side is satisfied: 65<n1A2<110.