(under the class definition) Subject matter in which the lens or film gate is moved to a position remote from its normal operative position to facilitate the focusing of the lens.
SEE OR SEARCH CLASS
359, Optics: Systems (Including Communication) and Elements,
380, 410 and 425+ for focusing systems for compound lens systems such as microscopes and telescopes, subclass 506 for focusing mechanisms and subclasses 823+ for axial adjustment of a single lens or lens system.
