Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear unit including a plurality of lens units. A distance between adjacent lens units changes during zooming. An aperture stop is arranged on an image side of the first lens unit. An image stabilizing unit Ls comprising at least part of the second lens unit moves in a direction perpendicular to an optical axis during blurring correction. The predetermined conditional expressions are satisfied.

Abstract: A zoom lens has a first positive lens unit having a positive refractive power, a second positive lens unit arranged adjacent to the first positive lens unit on its image side, a third positive lens unit arranged adjacent to the second positive lens unit on its image side, and a front lens group arranged on the object side of the first positive lens unit. Appropriate conditions concerning the refractive power of the front lens group, the focal length of the second positive lens unit, and the focal length of the zoom lens at the wide angle end are given.

Abstract: Provided is a zoom lens including a plurality of lens units, in which an interval between adjacent lens units changes during zooming. The zoom lens includes: a first lens subunit having a positive refractive power; a second lens subunit having a positive refractive power, which is arranged adjacent to an image side of the first lens subunit; and at least one lens unit on an object side of the first lens subunit. Lens systems arranged on the object side of the first lens subunit have a negative combined focal length over an entire zoom range. The second lens subunit moves along an optical axis to the image side during focusing from an object at infinity to a proximate object. A focal length of the first lens subunit and a focal length of the second lens subunit are appropriately set.

Abstract: A zoom lens has a first positive lens unit having a positive refractive power, a second positive lens unit arranged adjacent to the first positive lens unit on its image side, a third positive lens unit arranged adjacent to the second positive lens unit on its image side, and a front lens group arranged on the object side of the first positive lens unit. Appropriate conditions concerning the refractive power of the front lens group, the focal length of the second positive lens unit, and the focal length of the zoom lens at the wide angle end are given.

Abstract: Provided is a zoom lens including a plurality of lens units, in which an interval between adjacent lens units changes during zooming. The zoom lens includes: a first lens subunit having a positive refractive power; a second lens subunit having a positive refractive power, which is arranged adjacent to an image side of the first lens subunit; and at least one lens unit on an object side of the first lens subunit. Lens systems arranged on the object side of the first lens subunit have a negative combined focal length over an entire zoom range. The second lens subunit moves along an optical axis to the image side during focusing from an object at infinity to a proximate object. A focal length of the first lens subunit and a focal length of the second lens subunit are appropriately set.

Abstract: An optical element, which is composed of at least three optical members including a resin layer sandwiched between two optical members, has a high environmental resistance and optical performance, and has an excellent chromatic aberration correction effect. In the optical element, the resin layer is formed on one of light incident/exit surfaces of a first optical member, and a second optical member is cemented to the resin layer by a bonding material. A condition of ?g<?r is satisfied, where ?r indicates an outer diameter of the resin layer and ?g indicates a diameter of cemented surface of the resin layer and the second optical member.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a focus lens unit having a negative refractive power, configured to move in focusing, and a final lens unit having a positive refractive power, disposed closest to the image side. The focus lens unit and the final lens unit are disposed so as to be adjacent to each other, each lens unit moves so that a distance between adjacent lens units changes in zooming, and a focal length of the final lens unit fimg, a focal length of the focus lens unit ff, and a focal length of an entire system at a wide-angle end fw are appropriately set.

Abstract: An optical system includes, in order from an object side to an image side, a first lens unit of a positive refractive power, an aperture diaphragm, and a second lens unit of a positive refractive power. The first lens unit includes, in order from the object side to the image side, a cemented lens Lp1 made by joining a first lens of a positive refractive power and a second lens of a negative refractive power with each other, and a third lens of a positive refractive power which has a meniscus shape. The predetermined conditions are satisfied.

Abstract: An optical element is provided, which is small in distortion when at least three optical members including a resin layer sandwiched by the optical members are cemented together, has a high environmental resistance and optical performance, and has an excellent chromatic aberration correction effect. In the optical element, the resin layer is formed on one of light incident/exit surfaces of a first optical member, and a second optical member is cemented to the resin layer by a bonding material. A condition of ?g<?r is satisfied where ?r indicates an outer diameter of the resin layer and ?g indicates an effective region diameter of a surface of the second optical member which is cemented to the resin layer.

Abstract: An optical system includes, in order from an object side to an image side, a front unit having a positive refractive power, an aperture diaphragm, and a rear unit. The front unit includes a first lens unit having a positive refractive power. The rear unit includes a second unit adjacent to the aperture diaphragm and configured to move in focusing. The first lens unit includes n (which is an integer of 2 or higher) positive lenses and one or more negative lenses. The materials of at least two positive lenses of the n positive lenses in the first lens unit satisfy 0.0100<??gF where ??gF is an abnormal partial dispersion of each material. The material of one or more positive lenses of the n positive lenses in the first lens unit satisfies 0.0272<??gF. Additional conditional expressions are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear unit including a plurality of lens units. A distance between adjacent lens units changes during zooming. An aperture stop is arranged on an image side of the first lens unit. An image stabilizing unit Ls comprising at least part of the second lens unit moves in a direction perpendicular to an optical axis during blurring correction. The predetermined conditional expressions are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a focus lens unit having a negative refractive power, configured to move in focusing, and a final lens unit having a positive refractive power, disposed closest to the image side. The focus lens unit and the final lens unit are disposed so as to be adjacent to each other, each lens unit moves so that a distance between adjacent lens units changes in zooming, and a focal length of the final lens unit fimg, a focal length of the focus lens unit ff, and a focal length of an entire system at a wide-angle end fw are appropriately set.

Abstract: An optical system, in order from an object side to an image side, includes a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive or negative refractive power. The first lens unit is configured by a first partial lens unit and a second partial lens unit each having a positive refractive power. The first partial lens unit is configured by a positive single lens, and has at least one aspherical surface. The second partial lens unit is configured by a positive lens and a negative lens, and has a diffraction optical surface of a diffraction optical element rotationally symmetric with reference to an optical axis direction. The second lens unit is a focus lens unit that is movable in the optical axis direction. And a paraxial lateral magnification ?asph meets a predetermined condition.

Abstract: An optical apparatus of the present invention includes shake detectors 25p and 25y which detect a shake, electro-optic elements eo1 and eo2 which constitute a part of the optical system and change refractive-index distributions by an electro-optic effect in accordance with an applied voltage, and a drive unit 23 which applies a voltage to the electro-optic element so as to reduce an image blur detected by the shake detectors.

Abstract: An optical system includes, in order from an object side to an image side, a first lens unit having a positive refractive power, an aperture stop, and a rear lens group. In the optical system, the rear lens group includes a second lens unit configured to move during focusing. The first lens unit includes n positive lenses (n is an integer greater than 1) and one or more negative lenses. With an order of an optical member counted from the object side towards the image side being indicated by i (i is an integer equal to or greater than 1), a refractive index and an Abbe number of a material of an i-th positive lens of the first lens unit with respect to d-line light (Ndi, ?di), maximum and minimum values of the Abbe number ?di (max(?di), min(?di)), a minimum value of the refractive index Ndi (min(Ndi)), a focal length of the first lens unit (fp), and a focal length of the entire optical system (f) are appropriately set.

Abstract: A compound lens comprises three or more optical elements, including first, second, and third optical components, that are cemented together. The material of the second optical element is an organic composite material. The first optical element is cemented to one surface of the second optical element. The third optical element is disposed remotest from the first optical element in an optical axis. The diameters of effective areas of the first optical element on the cemented surface between the first and the second optical elements, and of the second optical element, and the distance ti(?) between optically effective surfaces of the i-th optical element (i=1, 2, 3) along the optical axis at diameter ? are appropriately designed. The second optical element has such a shape that the decrease in the distance between its optically effective surfaces is small in a region outside the effective surface area.

Abstract: An optical system, in order from an object side to an image side, includes a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive or negative refractive power. The first lens unit is configured by a first partial lens unit and a second partial lens unit each having a positive refractive power. The first partial lens unit is configured by a positive single lens, and has at least one aspherical surface. The second partial lens unit is configured by a positive lens and a negative lens, and has a diffraction optical surface of a diffraction optical element rotationally symmetric with reference to an optical axis direction. The second lens unit is a focus lens unit that is movable in the optical axis direction. And a paraxial lateral magnification ?asph meets a predetermined condition.

Abstract: An optical system includes, in order from an object side to an image side, a first lens unit having a positive refractive power, an aperture stop, and a rear lens group. In the optical system, the rear lens group includes a second lens unit configured to move during focusing. The first lens unit includes n positive lenses (n is an integer greater than 1) and one or more negative lenses. With an order of an optical member counted from the object side towards the image side being indicated by i (i is an integer equal to or greater than 1), a refractive index and an Abbe number of a material of an i-th positive lens of the first lens unit with respect to d-line light (Ndi, ?di), maximum and minimum values of the Abbe number ?di (max(?di), min(?di)), a minimum value of the refractive index Ndi (min(Ndi)), a focal length of the first lens unit (fp), and a focal length of the entire optical system (f) are appropriately set.

Abstract: A compound lens comprises three or more optical elements, including first, second, and third optical components, that are cemented together. The material of the second optical element is an organic composite material. The first optical element is cemented to one surface of the second optical element. The third optical element is disposed remotest from the first optical element in an optical axis. The diameters of effective areas of the first optical element on the cemented surface between the first and the second optical elements, and of the second optical element, and the distance ti(?) between optically effective surfaces of the i-th optical element (i=1, 2, 3) along the optical axis at diameter ? are appropriately designed. The second optical element has such a shape that the decrease in the distance between its optically effective surfaces is small in a region outside the effective surface area.

Abstract: An optical apparatus of the present invention includes shake detectors 25p and 25y which detect a shake, electro-optic elements eo1 and eo2 which constitute a part of the optical system and change refractive-index distributions by an electro-optic effect in accordance with an applied voltage, and a drive unit 23 which applies a voltage to the electro-optic element so as to reduce an image blur detected by the shake detectors.