Abstract: A lens system includes sequentially from an object side: a first lens group having a positive refractive power; an aperture diaphragm; a second lens group having a positive refractive power; and a third lens group having a positive refractive power and moving along a direction of an optical axis when focusing from an object at infinity to a close object. Assuming that L is a distance from a lens surface of the first lens group closest to the object side to a lens surface closest to an image side on the optical axis, Y is a maximum image height, f1 is a focal length of the first lens group, and f is a focal length of the entire lens system, the lens system satisfies the following conditions: 1.0<L/Y<2.3, and 1<f1/f<3.

Abstract: A lens system is provided. The lens system includes a positive first lens group, an aperture diaphragm, a positive second lens group, and a third lens group, disposed sequentially from a subject side. The first lens group includes at least three positive lenses and at least one negative lens. The second lens group includes four or more lenses including at least one cemented lens. A negative lens with a concave surface toward the subject side is disposed at the subject side. The third lens group includes three or more lenses including at least one positive lens and at least one negative lens. When focusing is moving from an infinity-distance subject to a short-distance subject, the first lens group, the aperture diaphragm, and the second lens group move integrally toward the subject side, while the third lens group is fixed with respect to an image surface.

Abstract: A zoom lens includes a first lens group with a negative refractive power, a second lens group with a positive refractive power, and a third lens group with a positive refractive power. When the zoom lens changes from a wide angle end to a telephoto end, a spacing between the first lens group and the second lens group is reduced, and a spacing between the second lens group and the third lens group changes. The first lens group includes a first lens, a second lens, a third lens, and a fourth lens. Refractive powers of the first lens, the second lens, and the third lens are negative, and a refractive power of the fourth lens is positive. Abbe numbers of the first lens, the second lens, and the third lens are larger than 60. A ratio of a focal length of the first lens group over a focal length of the zoom lens at a wide angle end is larger than ?2.5 and smaller than ?1.2.

Abstract: A lens system includes a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a positive refractive power, and a fourth lens group having a negative refractive power. The first, second, third, and fourth lens groups are arranged in order from an object side of the lens system. During a change from focusing on a first object to focusing on a second object closer to the lens system than the first object, at least the second lens group and the third lens group move along an optical axis toward the object side. The lens system satisfies 0.7<|f4/f|<2.0, where f represents a focal length of the lens system, and f4 represents a focal length of the fourth lens group.

Abstract: A lens system is provided. The lens system includes a positive first lens group, an aperture diaphragm, a positive second lens group, and a third lens group, disposed sequentially from a subject side. The first lens group includes at least three positive lenses and at least one negative lens. The second lens group includes four or more lenses including at least one cemented lens. A negative lens with a concave surface toward the subject side is disposed at the subject side. The third lens group includes three or more lenses including at least one positive lens and at least one negative lens. When focusing is moving from an infinity-distance subject to a short-distance subject, the first lens group, the aperture diaphragm, and the second lens group move integrally toward the subject side, while the third lens group is fixed with respect to an image surface.

Abstract: A zoom lens includes a first lens group with a negative refractive power, a second lens group with a positive refractive power, and a third lens group with a positive refractive power. When the zoom lens changes from a wide angle end to a telephoto end, a spacing between the first lens group and the second lens group is reduced, and a spacing between the second lens group and the third lens group changes. The first lens group includes a first lens, a second lens, a third lens, and a fourth lens. Refractive powers of the first lens, the second lens, and the third lens are negative, and a refractive power of the fourth lens is positive. Abbe numbers of the first lens, the second lens, and the third lens are larger than 60. A ratio of a focal length of the first lens group over a focal length of the zoom lens at a wide angle end is larger than ?2.5 and smaller than ?1.2.

Abstract: The present disclosure provides a zoom lens, wherein a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having the positive refractive power are disposed from an object side to an image side in order; and when a zooming state is changed from a wide angle end state to a telescopic end state, at least the first lens group and the second lens group are movable.

Abstract: In a zoom lens, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having the positive refractive power are disposed from an object side to an image side; and in a phase of variable magnification from a wide-angle end to a telescopic end, the first lens group is moved and the second lens group is moved to the object side such that an air interval between the first lens group and the second lens group is decreased and an air interval between the second lens group and the third lens group is increased.

Abstract: A zoom lens includes three groups that are a negative first group, a positive second group, and a positive third group in order from an object side. The first group includes a negative cemented lens formed by joining together, from the object side, a first lens formed by a negative single lens and a second lens formed by a positive single lens. The second group includes, from the object side, a third lens formed by a positive single lens and a cemented lens formed by joining together a fourth lens formed by a positive single lens and a fifth lens formed by a negative single lens. The third group includes a sixth lens formed by a positive single lens.

Abstract: A zoom lens includes, in order from an object side to an image side: first, second and third lens groups having a negative refractive power, a positive refractive power and a positive refractive power, respectively. The first lens group includes a single compound aspheric lens formed of a spherical glass lens having a negative refractive power and a resin lens having a positive refractive power and an image side surface thereof is aspheric, and the conditional expressions (1) to (4) are satisfied f11/fw<?1.8,??(1) 1.55<n11,??(2) 55<?11, and??(3) G1r1<?16.5,??(4) where f11 and fw are focal lengths of the spherical glass lens and the whole lens system at a wide-angle end, respectively, n11 and ?11 are a refractive index and an Abbe number, respectively, of the spherical glass lens at the d-line, and G1r1 is a radius of curvature of an object side surface of the spherical glass lens.

Abstract: In a zoom lens, a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having the positive refractive power are disposed from an object side to an image side; and in a phase of variable magnification from a wide-angle end to a telescopic end, the first lens group is moved and the second lens group is moved to the object side such that an air interval between the first lens group and the second lens group is decreased and an air interval between the second lens group and the third lens group is increased.

Abstract: The present disclosure provides a zoom lens, wherein a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having the positive refractive power are disposed from an object side to an image side in order; and when a zooming state is changed from a wide angle end state to a telescopic end state, at least the first lens group and the second lens group are movable.

Abstract: A zoom lens includes three groups that are a negative first group, a positive second group, and a positive third group in order from an object side. The first group includes a negative cemented lens formed by joining together, from the object side, a first lens formed by a negative single lens and a second lens formed by a positive single lens. The second group includes, from the object side, a third lens formed by a positive single lens and a cemented lens formed by joining together a fourth lens formed by a positive single lens and a fifth lens formed by a negative single lens. The third group includes a sixth lens formed by a positive single lens.

Abstract: An image capturing apparatus includes: at least one or more vertically movable lens groups among at least three or more lens groups, which constitute a zoom lens, movable in an optical axis direction, the vertically movable lens group being movable in a direction substantially perpendicular to the optical axis; a zoom lens group among the three or more lens groups, the zoom lens group being movable in the optical axis direction; and a correction mechanism that corrects a position of the optical axis based on the three or more lens groups by moving the vertically movable lens group in a wide-angle end state to a predetermined position in the substantially perpendicular direction. When the vertically movable lens group is moved for the purpose of anti-vibration at each zoom position in the substantially perpendicular direction, the apparatus is configured to satisfy the following Conditional Expression (1). 0.7<(Lw+Bw)/Bt<1.

Abstract: A zoom lens includes, in order from an object side to an image side: first, second and third lens groups having a negative refractive power, a positive refractive power and a positive refractive power, respectively. The first lens group includes a single compound aspheric lens formed of a spherical glass lens having a negative refractive power and a resin lens having a positive refractive power and an image side surface thereof is aspheric, and the conditional expressions (1) to (4) are satisfied f11/fw<?1.8,??(1) 1.55<n11,??(2) 55<?11, and??(3) G1r1<?16.5,??(4) where f11 and fw are focal lengths of the spherical glass lens and the whole lens system at a wide-angle end, respectively, n11 and ?11 are a refractive index and an Abbe number, respectively, of the spherical glass lens at the d-line, and G1r1 is a radius of curvature of an object side surface of the spherical glass lens.

Abstract: An image capturing apparatus includes: at least one or more vertically movable lens groups among at least three or more lens groups, which constitute a zoom lens, movable in an optical axis direction, the vertically movable lens group being movable in a direction substantially perpendicular to the optical axis; a zoom lens group among the three or more lens groups, the zoom lens group being movable in the optical axis direction; and a correction mechanism that corrects a position of the optical axis based on the three or more lens groups by moving the vertically movable lens group in a wide-angle end state to a predetermined position in the substantially perpendicular direction. When the vertically movable lens group is moved for the purpose of anti-vibration at each zoom position in the substantially perpendicular direction, the apparatus is configured to satisfy the following Conditional Expression (1). 0.7<(Lw+Bw)/Bt<1.

Abstract: A zoom lens includes, in order from an object side, a first lens group having a negative power, a second lens group having a positive power, and a third lens group having a positive power. At least the first and second lens groups are movable during a change from a wide-angle end state in which a focal length becomes shortest to a telephoto end state in which the focal length becomes longest. The first lens group is constructed of a glass lens and a plastic lens, the glass lens being positioned on the object side and having a negative power, the plastic lens being positioned on an image side and having a positive power. The second lens group includes a single plastic lens having a negative power. The third lens group includes at least one plastic lens having a positive power. The lenses are satisfied predetermined conditions.

Abstract: There is provided a development cartridge capable of switching development colors in a plurality of development cartridges without using development rack. A development cartridge of the present invention has a part of a drive member for switching development colors.

Abstract: A zoom lens includes, in order from an object side, a first lens group having a negative power, a second lens group having a positive power, and a third lens group having a positive power. At least the first and second lens groups are movable during a change from a wide-angle end state in which a focal length becomes shortest to a telephoto end state in which the focal length becomes longest. The first lens group is constructed of a glass lens and a plastic lens, the glass lens being positioned on the object side and having a negative power, the plastic lens being positioned on an image side and having a positive power. The second lens group includes a single plastic lens having a negative power. The third lens group includes at least one plastic lens having a positive power. The lenses are satisfied predetermined conditions.

Abstract: A laser scanning optical apparatus wherein a plural number of beams are deflected by one polygon mirror and are scanned on respective corresponding photosensitive drums via a scanning optical system. The scanning optical system has a first scanning lens which transmits all the beams, exclusive second scanning lenses which transmit exclusively the respective beams and plane mirrors for reflecting the beams. The second scanning lenses are located such that at least one of the second scanning lenses is at a distance from the corresponding photosensitive drum on which the beam transmitted by the at least one of the second scanning lenses is scanned and that another second scanning lens is at another distance from the corresponding photosensitive drum on which the beams transmitted by the another second scanning lens is scanned.