Zoom lens, optical apparatus and method for manufacturing the zoom lens

A zoom lens, comprising, in order from an object:

• 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;
• a fourth lens group having a negative refractive power;
• and
• a fifth lens group having a positive refractive power, wherein:
• intervals between adjacent lens groups change and the first lens group, the second lens group, the third lens group, and the fourth lens group move upon zooming from a wide angle end state to a telephoto end state;
• and
• following conditional expressions are satisfied:
• 1.80<f1/(fw×ft)1/2<2.40;
• and
• 0.50<−f5/f4<1.00,
• where, f1 denotes a focal length of the first lens group,
• f4 denotes a focal length of the fourth lens group,
• f5 denotes a focal length of the fifth lens group,
• fw denotes a focal length of the zoom lens in the wide angle end state, and
• ft denotes a focal length of the zoom lens in the telephoto end state.

A zoom lens, comprising, in order from an object,

• 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;
• a fourth lens group having a negative refractive power;
• and
• a fifth lens group having a positive refractive power, wherein:
• intervals between adjacent lens groups change and the first lens group, the second lens group, the third lens group, and the fourth lens group move upon zooming from a wide angle end state to a telephoto end state;
• and
• following conditional expressions are satisfied:
• 0.86<−f4/(fw×ft)1/2<1.18;
• and
• 0.10<Dm4/(fw×ft)1/2<0.30,
• where, f4 denotes a focal length of the fourth lens group,
• Dm4 denotes a difference in position of the fourth lens group between the wide angle end state and the telephoto end state on an optical axis (displacement toward the object is positive),
• fw denotes a focal length of the zoom lens in the wide angle end state, and
• ft denotes a focal length of the zoom lens in the telephoto end state.

A method for manufacturing a zoom lens,

• the zoom lens comprising, in order from an object:
• 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;
• a fourth lens group having a negative refractive power;
• and
• a fifth lens group having a positive refractive power,
• the method comprising:
• disposing the first lens group to the fifth lens group in a lens barrel such that intervals between adjacent lens groups are changed and the first lens group, the second lens group, the third lens group, and the fourth lens group move upon zooming from a wide angle end state to a telephoto end state, and
• one of the following steps (A), (B) and (C):
• (A):
• satisfying the following conditional expressions:
• 1.80<f1/(fw×ft)1/2<2.60;
• and
• 0.75<−f4/(fw×ft)1/2<1.20,
• where, f1 denotes a focal length of the first lens group,
• f4 denotes a focal length of the fourth lens group,
• fw denotes a focal length of the zoom lens in the wide angle end state, and
• ft denotes a focal length of the zoom lens in the telephoto end state,
• (B):
• satisfying the following conditional expressions:
• 1.80<f1/(fw×ft)1/2<2.40;
• and
• 0.50<−f5/f4<1.00,
• where, f5 denotes a focal length of the fifth lens group, and
• (C):
• satisfying the following conditional expressions:
• 0.86<−f4/(fw×ft)1/2<1.18;
• and
• 0.10<Dm4/(fw×ft)1/2<0.30,
• where, Dm4 denotes a difference in position of the fourth lens group between the wide angle end state and the telephoto end state on an optical axis (displacement toward the object is positive).