Appeal No. 1997-1766
Application No. 08/245,033
element lens, such as a zoom lens or a fixed focal length
telephoto lens, is a difficult, complex matter, requiring
designing a lens unit so as to provide appropriate refractive
power while controlling various types of aberration in order
to attain a high level of optical performance. Appellant
points out that in zoom lenses, relative movement of the lens
unit during zooming creates serious aberration and aberration
variation problems that do not occur in fixed focal length
lenses, and that these problems must be solved if a high level
of optical performance is to be attained. Appellant points
out that unlike fixed focal length lenses, zoom lenses require
well-designed mechanical structures to provide the necessary
relative movement of the lens unit in zooming. Appellant
argues that because of the fundamental differences between
zoom lenses and fixed focal length lenses, it cannot be
assumed that a particular teaching regarding fixed focal
length lenses are applicable to zoom lenses. Appellant argues
that this is especially true when the zoom lenses are five-
unit lenses designed to provide desired optical and physical
characteristics, and that the fixed focal length lenses are
two-unit, three-unit or four-unit lenses which are not
-6-
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007