Abstract: An inner focus lens, in order from an object side to an image side, comprising: a first lens unit having positive optical power; a second lens unit having negative optical power; and a third lens unit having positive optical power, wherein the second lens unit is moved along an optical axis so that focusing from an infinite-distance object side to a short-distance object side is achieved, the first lens unit includes a bi-convex air lens, and the following conditions: 0.65<|f2/f|<5.00 and 0.5<f23/f1<9.0 (f2: a focal length of the second lens unit, f and f23: a focal length of the entire system and a composite focal length of the second and third lens units in an infinity in-focus condition, f1: a focal length of the first lens unit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system according to the present invention comprises a plurality of lens units and an aperture diaphragm arranged in the lens unit. The plurality of lens units include a focusing lens unit that is arranged on an object side relative to the aperture diaphragm and that moves in a direction along the optical axis at the time of focusing. Further, the zoom lens system satisfies at least one of the following conditions: (1) 1.2<|fF/fW|<6.0; and (2) 0.10<|fF/fT|<1.8 (here, fT/fW>3.0, fF: a focal length of the focusing lens unit, fT: a focal length of the entire system at a telephoto limit, fW: focal length of the entire system at a wide-angle limit).

Abstract: An easily manufacturable wide angle lens with less possibility of distortion even using a small number of lenses has a first lens which is a spherical meniscus lens having negative power and whose convex surface faces an object; the second lens which is an aspherical meniscus lens having negative power along an optical axis and has positive power off the optical axis and whose convex surface faces the object side; the third lens having positive power in order from an object side, and an aperture. The Abbe number of the second lens is 30 or less; the ratio between the diagonal length of an imaging device placed on an image plane and the focal length of the whole lens system is 0.26 or less; and the ratio between the focal length of the third lens and the focal length of the whole lens system is less than 1.5.

Abstract: An inner focus lens, in order from an object side to an image side, comprising: a first lens unit having positive optical power; a second lens unit having negative optical power; and a third lens unit having positive optical power, wherein the second lens unit is moved along an optical axis so that focusing from an infinite-distance object side to a short-distance object side is achieved, the first lens unit includes a bi-convex air lens, and the following conditions: 0.65<|f2/f|<5.00 and 0.5<f23/f1<9.0 (f2: a focal length of the second lens unit, f and f23: a focal length of the entire system and a composite focal length of the second and third lens units in an infinity in-focus condition, f1: a focal length of the first lens unit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit and further that can compensate an image blur caused by vibration applied to the entire system. The zoom lens system according to the present invention comprises a plurality of lens units and an aperture diaphragm arranged in the lens unit.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, and at least one subsequent lens unit having optical power, wherein in zooming from a wide-angle limit to a telephoto limit, the lens units are moved along an optical axis such that an air space between at least any two lens units among the lens units should vary, so that variable magnification is achieved, wherein the first lens unit includes a lens element having a reflecting surface for bending a light beam incident from the object, and wherein the condition is satisfied: 0.20<|fG1|/fT<0.52 (fT/fW?4.0, fG1 is a composite focal length of the first lens unit, and each of fT and fW is a focal length of the entire system at a telephoto limit or a wide-angle limit), an imaging device and a camera are provided.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a positive first lens unit, a negative second lens unit, a positive third lens unit, a negative fourth lens unit and a positive fifth lens unit, wherein the zoom lens system is provided with an image blur compensating lens unit moving in a direction perpendicular to an optical axis and being a part of the second lens unit or a part of the third lens unit, the first lens unit and the second lens unit individually move relative to an image surface in zooming, and the condition: TmainG/TsubG>3.0 (TmainG: an optical axial thickness of the lens unit containing the image blur compensating lens unit, TsubG: an optical axial thickness of the image blur compensating lens unit) is satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system according to the present invention, in order from an object side to an image side, comprises: a first lens unit having positive optical power; a second lens unit having negative optical power; a third lens unit having positive optical power; and an aperture diaphragm. At the time of zooming, the zoom lens system moves the first to third lens units so that intervals between these lens units vary. At the time of focusing from an infinity in-focus condition to a close-point object in-focus condition, the zoom lens system moves the third lens unit to the object side.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, a third lens unit having negative optical power, and a fourth lens unit having positive optical power, wherein the first lens unit moves along an optical axis, and the fourth lens unit is fixed relative to an image surface, in zooming from a wide-angle limit to a telephoto limit at the time of image taking, and the condition: 0.8<|fI/fW|<1.4 (fI: a composite focal length of the first lens unit, fW: a focal length of the entire system at a wide-angle limit) is satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, a third lens unit having negative optical power, and a fourth lens unit having positive optical power, wherein the first lens unit is composed of at least three lens elements, has at least one lens element having positive optical power, and moves along an optical axis in zooming, and the conditions: np>1.88 and 1.5<fp/fW<4.0 (np and fp: a refractive index to the d-line and a focal length of a lens element having the highest refractive index among the lens elements having positive optical power in the first lens unit, fW: a focal length of the entire system at a wide-angle limit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, a third lens unit having negative optical power, and a fourth lens unit having positive optical power, wherein the third lens unit moves along an optical axis in focusing from an infinity in-focus condition to a close-object in-focus condition, and the conditions: 0.5<|f3/fW|<2.0 and 0.005<d3/fW<0.070 (f3: a focal length of the third lens unit, d3: an optical axial thickness of the third lens unit, fW: a focal length of the entire system at a wide-angle limit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A compact imaging optical system having a light-weight focusing lens is provided. The imaging optical system includes, in order from an object side to an image side, a front unit in which a negative lens element is arranged closest to the object side, an aperture diaphragm, and a rear unit having positive optical power. In focusing from an infinite distance object to a short distance object, the negative lens element arranged closest to the object side and the aperture diaphragm are fixed with respect to an image surface, and a part of lens elements included in the front unit or the rear unit moves along an optical axis. The imaging optical system satisfies the following condition (1): 0.9<R/f<2.0 (R: an average between an image side curvature radius of the negative lens element arranged closest to the object side, and an image side curvature radius of a second negative lens element from the object side among all the negative lens elements; f: a focal length of the entire system).

Abstract: A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system according to the present invention comprises a plurality of lens units and an aperture diaphragm arranged in the lens unit. The plurality of lens units include: a negative lens unit that is arranged on an object side relative to the aperture diaphragm and provided with negative optical power having an absolute value greatest in the entire system and that moves in a direction along an optical axis at the time of zooming; and a focusing lens unit that is arranged in an optical path between the negative lens unit and the aperture diaphragm and that moves in a direction along the optical axis at the time of focusing such that an interval relative to the negative lens unit should vary.

Abstract: Compact and lightweight zoom lens systems having less aberration fluctuation in association with focusing, lens barrels, interchangeable lens apparatuses, and camera systems are provided. The zoom lens system comprises: a first lens unit having positive optical power; a first focusing lens unit which is located on an image side relative to the first lens unit, has negative optical power, and moves along an optical axis in zooming and focusing; and a second focusing lens unit which is located on the image side relative to the first focusing lens unit, has positive optical power, and moves along the optical axis in the zooming and the focusing, and satisfies the condition: |d2T/d1T|<1.0 (d1T: an amount of movement of the first focusing lens unit in focusing at a telephoto limit, d2T: an amount of movement of the second focusing lens unit in focusing at a telephoto limit).

Abstract: A zoom lens system comprising a plurality of lens units, wherein a lens unit located closest to an object side has positive optical power, among lens units located on the image side relative to an aperture diaphragm, a lens unit having negative optical power is at least one focusing lens unit which moves along an optical axis in focusing, an image blur compensating lens unit is provided, which moves in a direction perpendicular to the optical axis, in order to optically compensate image blur, the image blur compensating lens unit and the at least one focusing lens unit are arranged adjacent to each other, and the condition: 0.1<(T1+T2)/H<2.0 (T1 is an axial thickness of the lens unit located closest to the object side, T2 is an axial thickness of a lens unit located having one air space toward the image side from the lens unit located closest to the object side, H is an image height) is satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system comprising a plurality of lens units, each lens unit comprising at least one lens element, wherein a lens unit located closest to an object side has negative optical power, in zooming from a wide-angle limit to a telephoto limit at the time of image taking, the lens unit located closest to the object side and a lens unit located closest to an image side are fixed relative to an image surface, the lens unit located closest to the object side includes at least one lens element having positive optical power and at least one lens element having negative optical power, and an image blur compensating lens unit is provided, which moves in a direction perpendicular to an optical axis, in order to optically compensate image blur; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system, in order from an object side to an image side, comprises at least: a first lens unit having positive optical power; a second lens unit having negative optical power; a third lens unit having negative optical power; and an aperture diaphragm. At the time of zooming, the zoom lens system moves the first to third lens units so that intervals between these lens units vary. At the time of focusing from an infinity in-focus condition to a close-point object in-focus condition, the zoom lens system moves the third lens unit to the object side.

Abstract: A zoom lens system comprising a plurality of movable lens units which individually move along an optical axis at the time of zooming, wherein a lens unit located closest to an object side is fixed relative to an image surface at the time of zooming, at least two of the movable lens units are focusing lens units which move along the optical axis at the time of focusing in at least one zooming position, and the condition: 0.1<T1/fW<1.5 (T1: an axial thickness of the lens unit located closest to the object side, fW: a focal length of the entire system at a wide-angle limit) is satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system, in order from the object side to the image side, comprising a first lens unit, a second lens unit, a third lens unit and subsequent lens units including at least a fourth lens unit, wherein an aperture diaphragm is either included in the third lens unit or located on the image side relative to the third lens unit, at least two among the first to third lens units and the subsequent lens units are movable lens units which individually move along an optical axis at the time of zooming, at least two of the movable lens units are focusing lens units which move along the optical axis at the time of focusing from an infinity in-focus condition to a close-object in-focus condition in at least one zooming position, and at least the second lens unit and one of the subsequent lens units are the focusing lens units; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system comprising a plurality of movable lens units which individually move along an optical axis at the time of zooming from a wide-angle limit to a telephoto limit during image taking, wherein at least two of the movable lens units are focusing lens units which move along the optical axis at the time of focusing from an infinity in-focus condition to a close-object in-focus condition in at least one zooming position, and among the focusing lens units, a lens unit having the absolute value, which is not the greatest absolute value, of a wobbling value at a wide-angle limit is a wobbling lens unit which senses a moving direction of the focusing lens units at the time of focusing by wobbling itself in a direction along the optical axis; an interchangeable lens apparatus; and a camera system are provided.