BY MODIFYING OPTICAL IMAGE (E.G., TRANSMISSIVE OVERLAY):
(under the class definition) Subject matter which changes the visible appearance of an object so as to encrypt visible markings, or to decode the appearance of the object into intelligible visible markings.
SEE OR SEARCH CLASS
283, Printed Matter,
17, and 73 for an object with encrypted information printed or embossed thereon.
359, Optics: Systems (Including Communication) and Elements, appropriate subclasses for optically transmissive elements, particularly
1+, for a holos:graphic element; subclasses 619+ for a surface composed of lenticular elements; subclasses 885+ for an optical filter.
12, for unit or part identification, subclass 84 for key sheet controlling job mode, and subclasses 366+ for document handling of unauthorized copy prevention.