A method for manufacturing a zoom lens including, in order from an object:
- a front lens group having a positive refractive power;
- an M1 lens group having a negative refractive power;
- an M2 lens group having a positive refractive power;
- and an RN lens group having a negative refractive power, wherein
- the method comprising one of the following features A, B or C, wherein
- the feature A comprises:
- arranging the lens groups such that,
- upon zooming, a lens group nearest to the object in the M1 lens group is fixed with respect to an image surface, a distance between the front lens group and the M1 lens group changes, a distance between the M1 lens group and the M2 lens group changes, and a distance between the M2 lens group and the RN lens group changes,
- upon zooming from a wide-angle end state to a telephoto end state, the front lens group moves toward the object,
- upon focusing from an infinite distant object to a short distant object, the RN lens group moves, and
- the following conditional expressions are satisfied,
- 0.25
- <
- (
- -
- fF
- )
- /
- f
-
- 1
- <
- 0
- .
- 4
-
- 5
- 0.2
- <
- fTM
-
- 2
- /
- f
-
- 1
- ≤
- 0
- .
- 2
-
- 9
-
- 8
- 1.8
- <
- f
-
- 1
- /
- fw
- <
- 3
- .
- 5
-
- 0
- where
- fF:
- a focal length of the RN lens group,
- f1:
- a focal length of the front lens group,
- fTM2:
- a focal length of the M2 lens group in the telephoto end state, and
- fw:
- a focal length of the zoom optical system in the wide-angle end state,
- the feature B comprises:
- arranging the lens groups such that,
- upon zooming, the front lens group, the M1 lens group, the M2 lens group and the RN lens group move, a distance between the front lens group and the M1 lens group changes, a distance between the M1 lens group and the M2 lens group changes, and a distance between the M2 lens group and the RN lens group changes,
- upon zooming from a wide-angle end state to a telephoto end state, the front lens group moves toward the object,
- upon focusing from an infinite distant object to a short distant object, the RN lens group moves,
- the RN lens group comprises at least one lens having a positive refractive power, and at least one lens having a negative refractive power, and
- the following conditional expressions are satisfied,
- 2.7
- <
- fFP
- /
- (
- -
- fFN
- )
- <
- 4
- .
- 5
-
- 0
- 0.15
- <
- (
- -
- fTM
-
- 1
- )
- /
- f
-
- 1
- <
- 0
- .
- 3
-
- 5
- 0.2
- <
- fTM
-
- 2
- /
- f
-
- 1
- <
- 0.4
- where
- fFP:
- a focal length of a lens having a strongest positive refractive power in the RN lens group,
- fFN:
- a focal length of a lens having a strongest negative refractive power in the RN lens group,
- f1:
- a focal length of the front lens group,
- fTM1:
- a focal length of the M1 lens group in the telephoto end state, and
- fTM2:
- a focal length of the M2 lens group in the telephoto end state, and
- the feature C comprises:
- arranging the lens groups such that, upon zooming, a distance between the front lens group and the M1 lens group changes, a distance between the M1 lens group and the M2 lens group changes, and a distance between the M2 lens group and the RN lens group changes,
- upon focusing from an infinite distant object to a short distant object, the RN lens group moves, and
- the following conditional expressions are satisfied,
- 0.25
- <
- (
- -
- fF
- )
- /
- f
-
- 1
- <
- 0
- .
- 4
-
- 5
- 0.15
- <
- (
- -
- fTM
-
- 1
- )
- /
- f
-
- 1
- <
- 0
- .
- 3
-
- 5
- 0.2
- <
- fTM
-
- 2
- /
- f
-
- 1
- <
- 0.4
- 1.8
- <
- f
-
- 1
- /
- fw
- <
- 3.
- 5
-
- 0
- where
- fF:
- a focal length of the RN lens group,
- f1:
- a focal length of the front lens group,
- fTM1:
- a focal length of the M1 lens group in a telephoto end state,
- fTM2:
- a focal length of the M2 lens group in a telephoto end state, and
- fw:
- a focal length of the zoom optical system in a wide-angle end state.