(under subclass 665) Subject matter wherein at least one refracting surface of the lens is deformable to vary the
focal length of the lens.
(1) Note. The refracting surface of the lens may be accomplished by either applying mechanical force to the periphery of the lens casing or varying the quantity of fluid within the lens casing. In the type of fluid lens which has a freestanding surface tension formed refracting surface, the refracting surface may be deformed by impressing an electric potential upon the fluid lens.
SEE OR SEARCH CLASS
351, Optics: Eye Examining, Vision Testing and Correcting,
169, for spectacle lenses of the fluid type having a variable focal length.
