Patent ID: 11914125
Assignee: NIKON CORPORATION
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 25:
26. A method for manufacturing a zoom lens, comprising:
arranging, in a lens barrel and in order from an object, 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 having negative refractive power, and a fifth lens group having positive refractive power,
the first to fifth lens groups being arranged such that respective distances between all adjacent lens groups among the first to fifth lens groups are changed upon zooming,
further comprising one of the following features A or, wherein
the feature A comprising:
the first lens group being composed of three or more lenses, the second lens group consisting of a negative meniscus lens having a concave surface facing an image, a negative lens, a positive biconvex lens, and a negative lens, arranged in order from the object, the third lens group comprising two negative meniscus lenses both having a concave surface facing the image, the fourth lens group being composed of two or less lenses, the fifth lens group being composed of two or less lenses and moving upon zooming from a wide angle end state to a telephoto end state, the fifth lens group consisting of a positive lens and a negative lens, and
the following conditional expressions being satisfied:

0.01<D1/ft<0.15

0.03<Mv2/ft 

where
D1 denotes a distance on an optical axis from an object side surface of the first lens group to an image side surface of the first lens group,
ft denotes a focal length of the zoom lens in the telephoto end state, and
Mv2 denotes amount of movement of the second lens group upon zooming from the wide-angle end state to the telephoto end state, and
the feature B comprising:
the following conditional expressions being satisfied:

33.00<ft/(−f2)<46.00

43.00<β2t·β3t/(β2w·β3w)<65.00

where
ft denotes a focal length of the zoom lens in a telephoto end state,
f2 denotes a focal length of the second lens group,
β2t denotes magnification of the second lens group in the telephoto end state,
β3t denotes magnification of the third lens group in the telephoto end state,
β2w denotes magnification of the second lens group in a wide angle end state, and
β3w denotes magnification of the third lens group in the wide angle end state.