Abstract: Provided is a zoom lens, including, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; at least one lens unit that moves during zooming; and a rear lens unit including an aperture stop, in which a focal length of the zoom lens at a wide angle end, a focal length of the first lens unit, a focal length of the second lens unit, and a half angle of field of the zoom lens at the wide angle end are appropriately set.

Abstract: Provided is a zoom lens having a wide angle of field, a high zoom ratio, and high optical performance over the entire zoom range, and being small in size and lightweight. The zoom lens includes, in order from an object side to an image side: a first positive lens unit; a second negative lens unit; a third positive lens unit; a fourth positive lens unit; and at least one rear lens unit, in which: the first lens unit is configured not to move for zooming; the second lens unit, the third lens unit, and the fourth lens unit are configured to move while changing an interval between each pair of adjacent lens units during zooming; and the third lens unit (U3) is configured to move from the object side toward the image side during focusing from an object at infinity to an object at close distance.

Abstract: The zoom lens includes, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; at least one lens unit that moves during zooming; and a rear lens group including an aperture stop, wherein the rear lens group has a zooming rear lens unit that moves during zooming, and a refractive power of the rear lens group at a wide-angle end, a refractive power of the zooming rear lens unit, and a lateral magnification of the lens unit in the image side from the zooming rear lens unit, which is set at the wide-angle end and focuses on infinity, are appropriately set.

Abstract: Provided is a zoom lens having a wide angle of field, a high zoom ratio, and high optical performance over the entire zoom range, and being small in size and lightweight. The zoom lens includes, in order from an object side to an image side: a first positive lens unit; a second negative lens unit; a third positive lens unit; a fourth positive lens unit; and at least one rear lens unit, in which: the first lens unit is configured not to move for zooming; the second lens unit, the third lens unit, and the fourth lens unit are configured to move while changing an interval between each pair of adjacent lens units during zooming; and the third lens unit (U3) is configured to move from the object side toward the image side during focusing from an object at infinity to an object at close distance.

Abstract: A zoom lens include, from an object side: a positive first unit that does not move for zooming; a negative second unit that moves during zooming; a negative third unit that moves during zooming; a positive fourth unit that moves during zooming; and a positive fifth unit, wherein the second unit moves towards the image side during zooming towards a telephoto end, the third unit moves towards the object side during focus adjustment towards a close distance, and a focal length of the zoom lens at the wide angle end, a zoom ratio, a focal length of the zoom lens at a zoom position where the third unit is closest to the object, a focal length of the first unit, a focal length of the second unit, a focal length of the third unit, and a focal length of the fourth unit are appropriately set.

Abstract: A lens apparatus includes, in order from an object side: a first lens unit; an aperture stop; and a positive second lens unit. The first lens unit includes, in order from the object side, a first negative lens, a second negative lens having at least one aspheric surface, and a positive lens. The second lens unit includes at least one negative lens and at least two positive lenses. The first and second negative lenses of the first lens unit are meniscus lenses having a surface convex toward the object side. The focal length of the optical system, the focal lengths of the first and second lens units, the mean values of Abbe constants of the positive lens and the negative lenses of the first lens unit, and the mean values of Abbe constants of the positive lenses and the negative lenses of the second lens unit are appropriately configured.

Abstract: A zoom lens includes, in order from object side: a positive first unit immovable for zooming; a negative second unit moving during zooming; a third unit moving during zooming; a stop; and a positive fourth unit immovable for zooming. The first unit includes, in order from object side, a fixed negative front first unit, a positive middle first unit moving for focusing, and a fixed positive rear first lens unit. Each of the front first and the second units includes at least one positive lens and two negative lenses. Average of Abbe constants and average of partial dispersion ratios of positive lenses in the front first unit, average of Abbe constants and average of partial dispersion ratios of negative lenses in the front first unit, combined focal length of the positive lenses in the front first unit and focal length of the front first unit are appropriately set.

Abstract: Provided is a zoom lens, including, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; at least one lens unit that moves during zooming; and a rear lens unit including an aperture stop, in which a focal length of the zoom lens at a wide angle end, a focal length of the first lens unit, a focal length of the second lens unit, and a half angle of field of the zoom lens at the wide angle end are appropriately set.

Abstract: The zoom lens includes, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; at least one lens unit that moves during zooming; and a rear lens group including an aperture stop, wherein the rear lens group has a zooming rear lens unit that moves during zooming, and a refractive power of the rear lens group at a wide-angle end, a refractive power of the zooming rear lens unit, and a lateral magnification of the lens unit in the image side from the zooming rear lens unit, which is set at the wide-angle end and focuses on infinity, are appropriately set.

Abstract: A lens apparatus includes, in order from an object side: a first lens unit; an aperture stop; and a positive second lens unit. The first lens unit includes, in order from the object side, a first negative lens, a second negative lens having at least one aspheric surface, and a positive lens. The second lens unit includes at least one negative lens and at least two positive lenses. The first and second negative lenses of the first lens unit are meniscus lenses having a surface convex toward the object side. The focal length of the optical system, the focal lengths of the first and second lens units, the mean values of Abbe constants of the positive lens and the negative lenses of the first lens unit, and the mean values of Abbe constants of the positive lenses and the negative lenses of the second lens unit are appropriately configured.

Abstract: A zoom lens includes, in order from an object side, a positive first lens unit which does not move for zooming, a negative second lens unit which moves in an optical axis direction for zooming, a negative third lens unit which moves in the optical axis direction for zooming so as to correct image plane variation due to zooming, and a positive fourth lens unit which does not move for zooming. The fourth lens unit includes, in an order from the object side, a positive first sub lens unit and a positive second sub lens unit, which are separated by a largest air interval in the fourth lens unit. Abbe constants, partial dispersion ratios, and coefficients of the refractive index variation due to the temperature variation are appropriately set for lens materials forming the third lens unit, the first sub lens unit, and the second sub lens unit.

Abstract: a zoom lens includes, in order from object side: a positive first unit immovable for zooming; a negative second unit moving during zooming; a third unit moving during zooming; a stop; and a positive fourth unit immovable for zooming. The first unit includes, in order from object side, a fixed negative front first unit, a positive middle first unit moving for focusing, and a fixed positive rear first lens unit. Each of the front first and the second units includes at least one positive lens and two negative lenses. Average of Abbe constants and average of partial dispersion ratios of positive lenses in the front first unit, average of Abbe constants and average of partial dispersion ratios of negative lenses in the front first unit, combined focal length of the positive lenses in the front first unit and focal length of the front first unit are appropriately set.

Abstract: A wide-angle converter lens capable of being detachably mounted on an enlargement side of an imaging lens includes a first optical element, at least one optical element having negative refractive power, and at least one optical element having positive refractive power, wherein, when an average value of relative partial dispersions of the first optical element and all optical elements of which the sign of refractive power is the same as that of the first optical element is denoted by ?gF_ave, a relative partial dispersion of the first optical element is denoted by ?gF, and an Abbe number of the first optical element is denoted by ?d, these numerical values satisfy appropriate relationships.

Abstract: A wide-angle converter lens capable of being detachably mounted on an enlargement side of an imaging lens includes a first optical element, at least one optical element having negative refractive power, and at least one optical element having positive refractive power, wherein, when an average value of relative partial dispersions of the first optical element and all optical elements of which the sign of refractive power is the same as that of the first optical element is denoted by ?gF_ave, a relative partial dispersion of the first optical element is denoted by ?gF, and an Abbe number of the first optical element is denoted by ?d, these numerical values satisfy appropriate relationships.