Abstract: An object of the present invention is to provide a low-cost, miniature, wide-angle high-zoom-ratio zoom lens that has high imaging performance, and an imaging apparatus equipped with the zoom lens. To achieve the object, a zoom lens including a first lens group having positive refracting power, a second lens group having negative refracting power and a third lens group having positive refracting power in order from an object side in which a lens group P having positive refracting power is arranged closer to an image plane side than the third lens group.

Abstract: Provided are: a zoom lens which exhibits a large variable-power ratio, an increased degree of freedom with respect to aberration correction, and which has been achieved having a sufficient reduction in size in the optical axis direction; and an imaging device equipped therewith. The zoom lens includes at least, from the object side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group, and a fifth lens group, in that order. In the zoom lens, prescribed conditions are satisfied.

Abstract: An optical system of the present invention includes, in order from an object side: a first lens group G1; a second lens group G2 having positive refractive power; and a third lens group G3 having positive refractive power, wherein the first lens group G1 and the third lens group G3 are fixed in an optical axis direction while the second lens group G2 is moved in an optical axis direction to focus on from an object at infinity to an object at a finite distance, and specified conditions is satisfied.

Abstract: The optical system of the present invention includes, in order from an object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; and a third lens group G3 having positive refractive power, wherein the first lens group G1 and the third lens group G3 are fixed in an optical axis direction, while the second lens group G2 is moved in the optical axis direction to focus on from an object at infinity to an object at a finite distance, the third lens group G3 includes, in order from the object side: an object-side group G3a; an aperture stop S; and an image-side group G3b, and a specified condition is satisfied.

Abstract: Provided are: a zoom lens which exhibits a large variable-power ratio, an increased degree of freedom with respect to aberration correction, and which has been achieved having a sufficient reduction in size in the optical axis direction; and an imaging device equipped therewith. The zoom lens includes at least, from the object side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group, and a fifth lens group, in that order. In the zoom lens, prescribed conditions are satisfied.

Abstract: The zoom lens is composed of: an object side lens group at least including, in order from an object side: a first lens group G1 having positive refractive power; and a second lens group G2 having negative refractive power; and an image focusing side lens group including, in order from the object side: a negative lens group A having negative refractive power; and a negative lens group B arranged by facing the negative lens group A across an air distance, having negative refractive power. In the zoom lens, focusing from infinity to a close object is achieved by moving just the negative lens group A toward an image focusing side to satisfy a conditional expression below: [Expression 1] ?1.80<?2t<?0.94??(1) (1??At2)×?Bt<?4.

Abstract: A zoom lens exhibits a reduction in size, increased magnification, a reduction in variation of angle of view during zooming, and an increased focusing speed, said zoom lens being suitable for an imaging apparatus using a solid-state imaging device such as an interchangeable lens, a digital still camera, a digital video camera, or the like. The zoom lens has, in the lens system, at least: a first negative lens group having negative refractive power; a second negative lens group disposed further towards the image side than the first negative lens group, and which has negative refractive power; and a lens group (A) disposed so as to be adjacent to the image side of the second negative lens group. In the zoom lens, focusing from an infinite distance to a near object is performed by moving only the second negative lens group towards the image side, and prescribed conditions are satisfied.

Abstract: Provided are: a zoom lens which exhibits a large variable-power ratio, an increased degree of freedom with respect to aberration correction, and which has been achieved having a sufficient reduction in size in the optical axis direction; and an imaging device equipped therewith. The zoom lens includes at least, from the object side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group, and a fifth lens group, in that order. In the zoom lens, prescribed conditions are satisfied.

Abstract: The zoom lens is composed of: an object side lens group at least including, in order from an object side: a first lens group G1 having positive refractive power; and a second lens group G2 having negative refractive power; and an image focusing side lens group including, in order from the object side: a negative lens group A having negative refractive power; and a negative lens group B arranged by facing the negative lens group A across an air distance, having negative refractive power. In the zoom lens, focusing from infinity to a close object is achieved by moving just the negative lens group A toward an image focusing side to satisfy a conditional expression below: [Expression 1] ?1.80<?2t<?0.94??(1) (1??At2)×?Bt2<?4.

Abstract: Provided are: a zoom lens which exhibits a large variable-power ratio, an increased degree of freedom with respect to aberration correction, and which has been achieved having a sufficient reduction in size in the optical axis direction; and an imaging device equipped therewith. The zoom lens includes at least, from the object side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, a fourth lens group, and a fifth lens group, in that order. In the zoom lens, prescribed conditions are satisfied.

Abstract: The zoom lens includes at least, in order from an object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; a third lens group G3 having positive refractive power; a fourth lens group G4 having negative refractive power; and a fifth lens group G5 having negative refractive power. In the zoom lens, focusing from infinity to a proximity of object is achieved by movement of just fourth lens group toward an image focusing side and is characterized in Satisfaction of expressions below: [Expression 1] 2.1<?rt<3.5??(1) ?1.80<?2t<?0.94??(2) where “?rt” is composite lateral magnification at a telephoto end of lens groups locating closer to the image focusing side than the third lens group at infinity focusing, and “?2t” is lateral magnification at a telephoto end of the second lens group at infinity focusing.

Abstract: A zoom lens exhibits a reduction in size, increased magnification, a reduction in variation of angle of view during zooming, and an increased focusing speed, said zoom lens being suitable for an imaging apparatus using a solid-state imaging device such as an interchangeable lens, a digital still camera, a digital video camera, or the like. The zoom lens has, in the lens system, at least: a first negative lens group having negative refractive power; a second negative lens group disposed further towards the image side than the first negative lens group, and which has negative refractive power; and a lens group (A) disposed so as to be adjacent to the image side of the second negative lens group. In the zoom lens, focusing from an infinite distance to a near object is performed by moving only the second negative lens group towards the image side, and prescribed conditions are satisfied.

Abstract: An object of the present invention is to provide a low-cost, miniature, wide-angle high-zoom-ratio zoom lens that has high imaging performance, and an imaging apparatus equipped with the zoom lens. To achieve the object, a zoom lens including a first lens group having positive refracting power, a second lens group having negative refracting power and a third lens group having positive refracting power in order from an object side in which a lens group P having positive refracting power is arranged closer to an image plane side than the third lens group.

Abstract: The zoom lens includes at least, in order from an object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; a third lens group G3 having positive refractive power; a fourth lens group G4 having negative refractive power; and a fifth lens group G5 having negative refractive power. In the zoom lens, focusing from infinity to a proximity of object is achieved by movement of just fourth lens group toward an image focusing side and is characterized in Satisfaction of expressions below: [Expression 1] 2.1<?rt<3.5??(1) ?1.80<?2t<?0.94??(2) where “?rt” is composite lateral magnification at a telephoto end of lens groups locating closer to the image focusing side than the third lens group at infinity focusing, and “?2t” is lateral magnification at a telephoto end of the second lens group at infinity focusing.

Abstract: The zoom lens is composed of: an object side lens group at least including, in order from an object side: a first lens group G1 having positive refractive power; and a second lens group G2 having negative refractive power; and an image focusing side lens group including, in order from the object side: a negative lens group A having negative refractive power; and a negative lens group B arranged by facing the negative lens group A across an air distance, having negative refractive power. In the zoom lens, focusing from infinity to a close object is achieved by moving just the negative lens group A toward an image focusing side to satisfy a conditional expression below: [Expression 1] ?1.80<?2t<?0.94??(1) (1??At2)×?Bt2<?4.

Abstract: The zoom lens comprises the foremost or first lens group of positive refractive power located the closest to an object, the succeeding second lens group of negative refractive power, and the third lens group of positive refractive power, all arranged in this order, and if any, the rearmost lens group(s) closer to the imaging plane than the third lens group, all or part of the lens group(s) of negative refractive power behind the third lens group being moved in directions normal to the optical axis to serve as an anti-vibration lens for shifting an image. The zoom lens meets requirements as defined in the formula regarding a displacement of the first lens group, a focal length of the zoom lens at the wide-angle end, a focal length of the zoom lens at the telephoto end, and a focal length of the first lens group.

Abstract: The zoom lens comprises five or more groups of lens pieces, namely, the foremost or first lens group of positive refractive power located the closest to an object, the succeeding second lens group of negative refractive power, the third lens group of positive refractive power, the fourth lens group of positive refractive power, and the fifth lens group all arranged in this order, and if any, the rearmost lens group(s) closer to the imaging plane than the fifth lens group. The zoom lens meets requirements as defined in the formula regarding a synthetic optical power of the fifth lens group and, if any, the rearmost lens group(s) closer to the imaging plane than the fifth lens group while the zoom lens is taking a posture of the telephoto end.

Abstract: A zoom lens includes a first lens group including an optical path change member that changes an optical path, a second lens group including at least one negative lens and at least one positive lens, and lens groups having a positive refractive power. The first lens group is closer to an object side of the zoom lens and is fixed relative to an image plane during a zooming operation. The second lens group is adapted to move during the zooming operation. Each of the lens groups includes at least one positive lens, and the lens groups are closer to an image plane side of the zoom lens. The zoom lens satisfies vdLP>71, vdL2p<40, and ndL2m>1.71, wherein “vdLP” is an Abbe number, “vdL2p” is an Abbe number, and “ndL2m” is a refractive index.

Abstract: A zoom lens including: a first lens group having a positive refractive power; a second lens group having a negative refractive power; a third lens group having a positive refractive power; and a fourth lens group having a positive refractive power, wherein the first lens group, the second lens group, the third lens group, and the fourth lens group are sequentially arranged in the order from an object side to an image surface side, while zooming from a wide-angle position to a telephoto position, the first lens group is moved in such a way that the distance between the first lens group and the second lens group is widened, the second lens group is moved along a trajectory convex toward the image surface side, the third lens group is moved from the image surface side to the object side, and the fourth lens group is moved along a trajectory convex toward the object side, and the zoom lens satisfies the following inequalities: vd1ave>68.2, and Nd1ave>1.

Abstract: A photographic lens of a photographic apparatus which includes a plurality of lens groups may be manufactured using a method which includes correcting a focus deviation from a designed value generated in one lens group by adjusting a distance between lenses of another lens group. The distance between lenses may be adjusted using a washer. The lenses between which the distance is adjusted may include a positive lens and a negative lens, and the lens group having the lenses between which the distance is adjusted may have a negative refractive power.