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 comprising: a negative first lens unit including at least one positive lens element; a positive second lens unit including at least one negative lens element; and subsequent lens units including an aperture diaphragm, wherein the subsequent lens units include a most-image-side lens unit fixed to an image surface in focusing, a first focusing lens unit is provided between the aperture diaphragm and the most-image-side lens unit, and the conditions: 1.0<LSW/{fT×tan(?T)}<2.6 and 0.8<LG1G2/fW<2.8 (LSW: axial distance from aperture diaphragm to image surface at wide-angle limit, fT: focal length of entire system at telephoto limit, ?T: half view angle at telephoto limit, LG1G2; axial distance between most-image-side lens element in first lens unit and most-object-side lens element in second lens unit at wide-angle limit, fW: focal length of entire system at wide-angle limit) are satisfied.

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 zoom lens system comprising a negative first lens unit, a positive second lens unit, a negative third lens unit, and a positive fourth lens unit, wherein the second lens unit is composed of an object-side second lens unit and an image-side second lens unit, the object-side second lens unit has positive optical power, an aperture diaphragm is located between the object-side second lens unit and the image-side second lens unit, and the conditions: ?0.5<f2O/f2I<1.0 and 0.12<d2O/fW<0.35 (f2O: a composite focal length of the object-side second lens unit, f2I: a composite focal length of the image-side second lens unit, d2O: an optical axial distance from a most object side lens surface of the object-side second lens unit to the aperture diaphragm, fW: a focal length of the entire system at a wide-angle limit) are satisfied.

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, 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<|f1/fW|<1.4 (f1: 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: There are provided an inner focus lens consisting of a first lens group, an aperture diaphragm, and a second lens group in order from an object side. The first lens group has a positive first lens element, a positive second lens element, and a negative third lens element; or a positive first lens element, a positive second lens element, a positive third lens element, and a negative fourth lens element, in order from the object side. One lens element in the second lens group is moved with respect to an image surface in focusing, some of the lens elements thereof are moved in a direction perpendicular to an optical axis. The inner focus lens satisfies 0.2<|fF/fO|<3.0 (fF: a focal distance of a focus lens, fO: a synthetic focal distance of the lens elements moving in the direction perpendicular to the optical axis).

Abstract: There are provided an inner focus lens consisting of a first lens group, an aperture diaphragm, and a second lens group in order from an object side. The first lens group has a positive first lens element, a positive second lens element, and a negative third lens element, or has a positive first lens element, a positive second lens element, a positive third lens element, and a negative fourth lens element, in order from the object side. One lens element in the second lens group is moved with respect to an image surface in focusing. The second lens group has five or more lens elements, and has a configuration including a negative lens element, a positive lens element, and a positive lens element in order from the object side.

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, 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: 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, 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; a third lens unit having positive optical power; a fourth lens unit having negative optical power, and a subsequent lens unit, wherein the first lens unit comprises a negative lens element having negative optical power, and a positive lens element having positive optical power, and wherein the conditions: 1.47<nd2<1.57 and 60<?d2<75 (nd2: a refractive index to a d-line of the positive lens element, ?d2: an Abbe number to a d-line of the positive lens element) are satisfied.

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.

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 zoom lens system comprising a negative first lens unit, a positive second lens unit, a negative third lens unit, and a positive fourth lens unit, wherein the first lens unit and the third lens unit move along an optical axis, and the fourth lens unit is fixed with respect to an image surface in zooming, the third lens unit moves along the optical axis in focusing, and the conditions: 0.0<|M3/fW|<0.5 and 0.2<|f3/f4|<1.0 (M3: an amount of movement of the third lens unit in zooming, f3: a composite focal length of the third lens unit, f4: a composite focal length of the fourth lens unit, fW: a focal length of the entire system at a wide-angle limit) are satisfied.

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: 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: There are provided an inner focus lens consisting of a first lens group, an aperture diaphragm, and a second lens group in order from an object side. The first lens group has a positive first lens element, a positive second lens element, and a negative third lens element, or has a positive first lens element, a positive second lens element, a positive third lens element, and a negative fourth lens element, in order from the object side. One lens element in the second lens group is moved with respect to an image surface in focusing. The second lens group has five or more lens elements, and has a configuration including a negative lens element, a positive lens element, and a positive lens element in order from the object side.

Abstract: There are provided an inner focus lens consisting of a first lens group, an aperture diaphragm, and a second lens group in order from an object side. The first lens group has a positive first lens element, a positive second lens element, and a negative third lens element; or a positive first lens element, a positive second lens element, a positive third lens element, and a negative fourth lens element, in order from the object side. One lens element in the second lens group is moved with respect to an image surface in focusing, some of the lens elements thereof are moved in a direction perpendicular to an optical axis. The inner focus lens satisfies 0.2<|fF/fO|<3.0 (fF: a focal distance of a focus lens, fO: a synthetic focal distance of the lens elements moving in the direction perpendicular to the optical axis).

Abstract: A zoom lens system of lens units, the system including, in object-side-to-image-side order: a first lens unit having positive optical power; a second lens unit; an aperture diaphragm; one or more additional lens units, with a first of the additional lens units being a first focusing-lens unit having negative optical power and moving along the optical axis in the zoom lens system focusing; an image blur compensating lens unit, adjacent the first focusing-lens unit and movable in a direction perpendicular to the optical axis in order to optically compensate image blur; with the lens system satisfying: 0.1<(T1+T2)/H<2.0 (T1 being the axial thickness of the first lens unit, T2 being the axial thickness of the second lens unit, and H being the height of an image the zoom lens system forms on an image surface on the image-side end of the zoom lens system).