(under subclass 74) Subject matter including adjustable structure to focus the image of the object on the screen or to increase or decrease the size of the image relative to the size of the object.
SEE OR SEARCH THIS CLASS, SUBCLASS:
69, for changing focus for warped film or varying size, thickness or density of slides or film.
101, for lenses which are adjustable for forming or varying the magnification.
SEE OR SEARCH CLASS
352, Optics: Motion Pictures,
140, for motion-picture devices with focus control. 355, Photocopying,
55+, for a projection printer having focus or magnification control.
359, Optics: Systems (Including Communication) and Elements,
813+, 821, 823+, 827+, and 694+ for adjustable lens supports or mounts.
396, Photography,
89+, for cameras having focusing means.
399, Electrophotography,
9+, for diagnostics, subclasses 38+ for controls, subclasses 130+ for image formation, subclasses 168+ for charging, subclasses 177+ for exposure, and subclasses 222+ for development.
