Soft-focus lens system
AssigneePENTAX Corporation
InventorTakayuki Sensui
Life of this patent
Estimating the term…
Abstract
A soft-focus lens system includes a master lens group and a soft-focus lens group. The soft-focus lens group includes a positive sub lens group and a negative sub lens group. The positive sub lens group and the negative sub lens group are moved to set the normal photographing mode or the soft-focus photographing mode. Each of the sub lens groups is arranged to move with respect to the master lens group and the other of the sub lens groups so that the focal point and the focal length are not substantially varied before and after the switching of the soft-focus photographing mode to the normal photographing mode or vice versa.
Claims16
A soft-focus lens system comprising a positive master lens group and a negative soft-focus lens group,
- wherein said master lens group comprises two sub lens groups F1 and F2, and a diaphragm is provided therebetween;
- wherein at least one of said sub lens groups F1 and F2 of said master lens group is made moveable along the optical axis in order to set a normal photographing mode or a soft-focus photographing mode in which larger field curvature is occurred than in said normal photographing mode;
- wherein said negative soft-focus lens group comprises a positive sub lens group and a negative sub lens group, which are independently moveable with respect to said master lens group;
- wherein said positive sub lens group and said negative sub lens group are moved to set said normal photographing mode or said soft-focus photographing mode in which larger spherical aberration is occurred than in said normal photographing mode.
A soft-focus lens system comprising a positive master lens group and a negative soft-focus lens group,
- wherein said negative soft-focus lens group comprises a positive sub lens group and a negative sub lens group, which are independently moveable with respect to the master lens group;
- wherein said positive sub lens group and said negative sub lens group are moved to set a normal photographing mode or a soft-focus photographing mode in which larger spherical aberration is occurred than in said normal photographing mode;
- wherein each of said positive sub lens group and said negative sub lens group is arranged to move with respect to said master lens group and the other of said sub lens groups so that the focal point and the focal length are not varied before and after the switching of said soft-focus photographing mode to said normal photographing mode or vice versa.
Dependencies are inferred from the claim text.