Abstract: There are provided a camera system and an interchangeable lens that are compatible with a contrast detection method. A camera system (1) has an interchangeable lens unit (2) and a camera body (3). A lens microcomputer (40) changes the movable range of a second lens group (L2) via a focus lens drive controller (41) depending on whether a second holder (61) is driven by the focus lens drive controller (41) and a focus motor (80) on the basis of angle information inputted to a zoom ring (64) of the interchangeable lens unit (2), or the second holder (61) is driven by the focus lens drive controller (41) on the basis of contrast information.

Abstract: A zoom lens system comprising a plurality of lens units each composed of at least one lens element, wherein the zoom lens system, in order from the object side to the image side, comprises: a first lens unit having positive optical power and comprising four lens elements; a second lens unit having negative optical power; and a third lens unit having positive optical power; wherein in zooming from a wide-angle limit to a telephoto limit at the time of image taking, at least the first lens unit is moved along an optical axis direction so as to achieve variable magnification, and wherein the conditions are satisfied: 0.30<f1/fT<0.70 and Z=fT/fW>20.5 (f1 is a composite focal length of the first lens unit, fW is a focal length of the entire system at a wide-angle limit, and fT is a focal length of the entire system at a telephoto limit), an imaging device and a camera are provided.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a cemented lens element fabricated by two lens elements having optical power of mutually different signs and one single lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: There are provided a camera system and an interchangeable lens that are compatible with a contrast detection method. A camera system (1) has an interchangeable lens unit (2) and a camera body (3). A lens microcomputer (40) changes the movable range of a second lens group (L2) via a focus lens drive controller (41) depending on whether a second holder (61) is driven by the focus lens drive controller (41) and a focus motor (80) on the basis of angle information inputted to a zoom ring (64) of the interchangeable lens unit (2), or the second holder (61) is driven by the focus lens drive controller (41) on the basis of contrast information.

Abstract: A zoom lens system comprising a plurality of lens units each composed of at least one lens element, wherein the zoom lens system, in order from the object side to the image side, comprises: a first lens unit having positive optical power and comprising four lens elements; a second lens unit having negative optical power; and a third lens unit having positive optical power; wherein in zooming from a wide-angle limit to a telephoto limit at the time of image taking, at least the first lens unit is moved along an optical axis direction so as to achieve variable magnification, and wherein the conditions are satisfied: 0.30<f1/fT<0.70 and Z=fT/fW>20.5 (f1 is a composite focal length of the first lens unit, fW is a focal length of the entire system at a wide-angle limit, and fT is a focal length of the entire system at a telephoto limit), an imaging device and a camera are provided.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a cemented lens element fabricated by two lens elements having optical power of mutually different signs and one single lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a single third lens element, a cemented lens element of two lens elements having power of mutually different signs and a single sixth lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a cemented lens element fabricated by two lens elements having optical power of mutually different signs and one single lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a first cemented lens element of two lens elements having power of mutually different signs and a second cemented lens element of two lens elements having power of mutually different signs; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a cemented lens element fabricated by two lens elements having optical power of mutually different signs and one single lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?i W<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: A zoom lens system comprising a first lens unit having negative power, a second lens unit having positive power and a third lens unit having positive power, wherein: the first lens unit comprises a first lens element having a concave surface at least on the image side and negative power and a second lens element having a convex surface at least on the object side and positive power; the second lens unit comprises a single third lens element, a cemented lens element of two lens elements having power of mutually different signs and a single sixth lens element; in zooming, all of the lens units move along an optical axis; and conditions (1): 5.0<?iW<20.0 and (I-2): n11?1.9 (where, 3.

Abstract: It is an object to provide a zoom lens made of three groups having a zoom ratio of ×2.5 to ×3.2 if the object distance is ?, an field angle at the wide-angle end of 60° to 70°, high resolution, and a short optical total length when not in use. The zoom lens is made of a first lens group (G1) with a negative power, a second lens group (G2) with a positive power, and a third lens group (G3) with a positive power, arranged in that order from an object side to an image plane (S) side. The first lens group (G1) is made of a first lens (L1) that is a negative meniscus lens whose surface with strong curvature is facing the image plane (S) side and a second lens (L2) that is a positive meniscus lens whose surface with strong curvature is facing the object side, arranged in that order from the object side.

Abstract: A zoom lens comprising, disposed in order from an object side to an image surface side, a negative-power first lens group, a diaphragm, a positive-power second lens group, and a positive power third lens group, characterized in that, when zooming from a wide-angle end to a telelscope end, an air gap between the first lens group and the second lens group shrinks and an air gap between the second lens group and the third lens group expands, the third lens group is movable in an optical axis direction for focusing, and a zoom ratio at a shooting distance of ? is 2.5- to 3.2-magnification.

Abstract: A zoom lens comprising, disposed in order from an object side to an image plane side, a first lens group with a negative power, an aperture stop, a second lens group with a positive power, and a third lens group with a positive power, characterized in that, when zooming from a wide-angle end to a telescope end, an air gap between the first lens group and the second lens group is reduced and an air gap between the second lens group and the third lens group is increased, the third lens group can be moved in the direction of the optical axis for focus adjustment, and a zoom ratio is ×2.5 to ×3.2 if a shooting distance is ∞.

Abstract: Where a stack projection operation is carried out using first and second projection display units, it is arranged such that the first projection display unit projects a crosshatch pattern continuously in time while on the other hand, the second projection display unit projects a pattern identical with that crosshatch pattern such that the pattern flashes at given intervals of time. Thereafter, the state of superposition between the patterns projected from the two projection display units is examined to carry out inter-set convergence adjustment between the display units.