Abstract: 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 positive refractive power are arranged in order from an object, and zooming is performed by changing distances between each lens group, and the first lens group (G1) is composed of three or more lenses, the fourth lens group (G4) is composed of two or less lenses, and the fifth lens group (G5) is composed of two or less lenses and moves to an image surface side upon zooming from a wide angle end state to a telephoto end state, and the following conditional expression (1) is satisfied. 8.40<f1/(?f2)??(1) where, f1 denotes a focal length of the first lens group (G1), and f2 denotes a focal length of the second lens group (G2).

Abstract: A zoom lens (ZL) comprises, in order from an object: a first lens group (G1) having negative refractive power; an aperture stop (S); a second lens group (G2) having positive refractive power; a third lens group (G3) having negative refractive power; and a fourth lens group (G4) having positive refractive power. In this zoom lens (ZL), upon zooming from a wide angle end state to a telephoto end state, a distance between the aperture stop (S) and the first lens group (G1), a distance between the aperture stop (S) and the second lens group (G2), and a distance between the aperture stop (S) and the third lens group (G3) are changed and the aperture stop (S) is moved in an optical axis direction.

Abstract: A zoom lens, comprises: in order from an object, 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 positive refractive power, wherein, upon zooming from a wide-angle end state to a telephoto end state, a distance between each of lens groups and a lens group adjacent thereto changes to satisfy the following conditional expression: 2.90<|MV5/MV2|<11.50 where, MV5 denotes, upon zooming from a wide-angle end state to a telephoto end state, a moving amount of the fifth lens group with an image surface as a reference; and MV2 denotes, upon zooming from the wide-angle end state to the telephoto end state, a moving amount of the second lens group with the image surface as the reference.

Abstract: A zoom lens, comprises: in order from an object, 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 positive refractive power, wherein, upon zooming from a wide-angle end state to a telephoto end state, a distance between each of lens groups and a lens group adjacent thereto changes to satisfy the following conditional expression: 2.90<|MV5/MV2|<11.50 where, MV5 denotes, upon zooming from a wide-angle end state to a telephoto end state, a moving amount of the fifth lens group with an image surface as a reference; and MV2 denotes, upon zooming from the wide-angle end state to the telephoto end state, a moving amount of the second lens group with the image surface as the reference.

Abstract: A zoom lens (ZL) comprises, in order from an object: a first lens group (G1) having negative refractive power; an aperture stop (S); a second lens group (G2) having positive refractive power; a third lens group (G3) having negative refractive power; and a fourth lens group (G4) having positive refractive power. In this zoom lens (ZL), upon zooming from a wide angle end state to a telephoto end state, a distance between the aperture stop (S) and the first lens group (G1), a distance between the aperture stop (S) and the second lens group (G2), and a distance between the aperture stop (S) and the third lens group (G3) are changed and the aperture stop (S) is moved in an optical axis direction.

Abstract: An optical system comprises a first lens group having positive refractive power, a second lens group having positive refractive power, and a third lens group having negative refractive power, arranged in order from an object side. When focusing, the second lens group moves along an optical axis. The optical system satisfies the following conditional expression 0.30<{1?(?2)2}×(?3)2<2.00 where ?2 is a lateral magnification of the second lens group for a state of focusing on infinity, and ?3 is a lateral magnification of the third lens group.

Abstract: An optical system comprises a first lens group having positive refractive power, a second lens group having positive refractive power, and a third lens group having negative refractive power, arranged in order from an object side. When focusing, the second lens group moves along an optical axis. The optical system satisfies the following conditional expressions 0.100<BFa/f<0.500 and ?5.000<(?G1R1)/f<500.000 where BFa is an air equivalent distance on the optical axis from a lens surface on an image side to an image surface for the lens disposed farthest on the image side in the optical system, f is a focal length of the optical system, and G1R1 is a radius of curvature of the lens surface on the object side for a lens component disposed farthest on the object side in the first lens group.

Abstract: A zoom lens, comprises: in order from an object, 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 positive refractive power, wherein, upon zooming from a wide-angle end state to a telephoto end state, a distance between each of lens groups and a lens group adjacent thereto changes to satisfy the following conditional expression: 2.90<|MV5/MV2|<11.50 where, MV5 denotes, upon zooming from a wide-angle end state to a telephoto end state, a moving amount of the fifth lens group with an image surface as a reference; and MV2 denotes, upon zooming from the wide-angle end state to the telephoto end state, a moving amount of the second lens group with the image surface as the reference.

Abstract: A zoom lens (ZL) comprises, in order from an object: a first lens group (G1) having negative refractive power; an aperture stop (S); a second lens group (G2) having positive refractive power; a third lens group (G3) having negative refractive power; and a fourth lens group (G4) having positive refractive power. In this zoom lens (ZL), upon zooming from a wide angle end state to a telephoto end state, a distance between the aperture stop (S) and the first lens group (G1), a distance between the aperture stop (S) and the second lens group (G2), and a distance between the aperture stop (S) and the third lens group (G3) are changed and the aperture stop (S) is moved in an optical axis direction.

Abstract: 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 positive refractive power are arranged in order from an object, and zooming is performed by changing distances between each lens group, and the first lens group (G1) is composed of three or more lenses, the fourth lens group (G4) is composed of two or less lenses, and the fifth lens group (G5) is composed of two or less lenses and moves to an image surface side upon zooming from a wide angle end state to a telephoto end state, and the following conditional expression (1) is satisfied. 8.40<f1/(?f2)??(1) where, f1 denotes a focal length of the first lens group (G1), and f2 denotes a focal length of the second lens group (G2).

Abstract: 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 positive refractive power are arranged in order from an object, and zooming is performed by changing distances between each lens group, and the first lens group (G1) is composed of three or more lenses, the fourth lens group (G4) is composed of two or less lenses, and the fifth lens group (G5) is composed of two or less lenses and moves to an image surface side upon zooming from a wide angle end state to a telephoto end state, and the following conditional expression (1) is satisfied. 8.40<f1/(?f2)??(1) where, f1 denotes a focal length of the first lens group (G1), and f2 denotes a focal length of the second lens group (G2).

Abstract: A zoom lens, comprises: in order from an object, 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 positive refractive power, wherein, upon zooming from a wide-angle end state to a telephoto end state, a distance between each of lens groups and a lens group adjacent thereto changes to satisfy the following conditional expression: 2.90<|MV5/MV2|<11.50 where, MV5 denotes, upon zooming from a wide-angle end state to a telephoto end state, a moving amount of the fifth lens group with an image surface as a reference; and MV2 denotes, upon zooming from the wide-angle end state to the telephoto end state, a moving amount of the second lens group with the image surface as the reference.

Abstract: A zoom lens (ZL) comprises, in order from an object: a first lens group (G1) having negative refractive power; an aperture stop (S); a second lens group (G2) having positive refractive power; a third lens group (G3) having negative refractive power; and a fourth lens group (G4) having positive refractive power. In this zoom lens (ZL), upon zooming from a wide angle end state to a telephoto end state, a distance between the aperture stop (S) and the first lens group (G1), a distance between the aperture stop (S) and the second lens group (G2), and a distance between the aperture stop (S) and the third lens group (G3) are changed and the aperture stop (S) is moved in an optical axis direction.

Abstract: 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 positive refractive power are arranged in order from an object, and zooming is performed by changing distances between each lens group, and the first lens group (G1) is composed of three or more lenses, the fourth lens group (G4) is composed of two or less lenses, and the fifth lens group (G5) is composed of two or less lenses and moves to an image surface side upon zooming from a wide angle end state to a telephoto end state, and the following conditional expression (1) is satisfied. 8.40<f1/(?f2)??(1) where, f1 denotes a focal length of the first lens group (G1), and f2 denotes a focal length of the second lens group (G2).

Abstract: The present invention has, in order along the optical axis from the object side: a first lens group (G1) that has positive refractive power; a second lens group (G2) that has negative refractive power; a third lens group (G3) that has positive refractive power; a fourth lens group (G4) that has positive refractive power; and a fifth lens group (G5). The fourth lens group (G4) is constituted by a single positive lens (L41), and the fifth lens group (G5) is constituted by a single lens (L51), which is fixed with respect to an image plane while power is being varied. The following conditional expression (1) is satisfied. 0.9<?2t·?3w/(?2w·?3t)<1.7 . . . (1), where ?2w denotes a magnification of the second lens group (G2) in the wide-angle end state, ?3w denotes a magnification of the third lens group (G3) in the wide-angle end state, ?2t denotes a magnification of the second lens group (G2) in the telephoto end state, and ?3t denotes a magnification of the third lens group (G3) in the telephoto end state.

Abstract: The present invention has, in order along the optical axis from the object side: a first lens group (G1) that has positive refractive power; a second lens group (G2) that has negative refractive power; a third lens group (G3) that has positive refractive power; a fourth lens group (G4) that has positive refractive power; and a fifth lens group (G5). The fourth lens group (G4) is constituted by a single positive lens (L41), and the fifth lens group (G5) is constituted by a single lens (L51), which is fixed with respect to an image plane while power is being varied. The following conditional expression (1) is satisfied. 0.9<?2t·?3w/(?2w·?3t)<1.7 . . . (1), where ?2w denotes a magnification of the second lens group (G2) in the wide-angle end state, ?3w denotes a magnification of the third lens group (G3) in the wide-angle end state, ?2t denotes a magnification of the second lens group (G2) in the telephoto end state, and ?3t denotes a magnification of the third lens group (G3) in the telephoto end state.

Abstract: A zoom lens ZL comprising a first lens group G1 having negative refractive power, 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 includes a first lens having negative refractive power and a second lens which is a plastic lens having positive refractive power, the second lens group G2 includes a third lens having positive refractive power, a fourth lens having positive refractive power and a fifth lens having negative refractive power, the third lens group G3 includes a sixth lens having positive refractive power, and the conditional expressions: 1.50<(?f1)/fw<2.52, 0.4<(?f1)/fL2 <0.8, n2×n2×?2<77.0 are satisfied respectively.

Abstract: A zoom lens includes, in order from an object, a first lens group G1 having negative refractive power; a second lens group G2 having positive refractive power; and a third lens group G3 having positive refractive power. The first lens group G1 comprises only one negative spherical lens (lens L11) and one plastic positive lens (lens L12) separated by an air gap. The second lens group G2 comprises three or fewer lenses, including a positive lens component (cemented lens comprising a lens L21 and a lens L22), and one plastic negative lens (lens L23). The following conditional expressions are satisfied: 0.50<f1PL/(?f2PL)<2.50 and 0.80<(?f1)/f2<1.35, where f1PL is a focal length of the plastic positive lens forming the first lens group G1, f2PL is the focal length of the plastic negative lens forming the second lens group G2, f1 is the focal length of the first lens group G1, and f2 is the focal length of the second lens group G2.

Abstract: A zoom lens ZL comprising a first lens group G1 having negative refractive power, 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 includes a first lens having negative refractive power and a second lens which is a plastic lens having positive refractive power, the second lens group G2 includes a third lens having positive refractive power, a fourth lens having positive refractive power and a fifth lens having negative refractive power, the third lens group G3 includes a sixth lens having positive refractive power, and the conditional expressions: 1.50<(?f1)/fw<2.52, 0.4<(?f1)/fL2<0.8, n2×n2×?2<77.0 are satisfied respectively.

Abstract: A zoom lens includes, in order from an object, a first lens group G1 having negative refractive power; a second lens group G2 having positive refractive power; and a third lens group G3 having positive refractive power. The first lens group G1 comprises only one negative spherical lens (lens L11) and one plastic positive lens (lens L12) separated by an air gap. The second lens group G2 comprises three or fewer lenses, including a positive lens component (cemented lens comprising a lens L21 and a lens L22), and one plastic negative lens (lens L23). The following conditional expressions are satisfied: 0.50<f1PL/(?f2PL)<2.50 and 0.80<(?f1)/f2<1.35, where f1PL is a focal length of the plastic positive lens forming the first lens group G1, f2PL is the focal length of the plastic negative lens forming the second lens group G2, f1 is the focal length of the first lens group G1, and f2 is the focal length of the second lens group G2.