Authenticating identification and security documents and other objects

A document comprising:

• a first surface;
• and
• a second surface, in which
• the first surface comprises a first set of print structures and a second set of print structures, and in which the first set of print structures and the second set of print structures cooperate to obscure a location on the first surface of the second set of print structures, and in which the second set of print structures are arranged on the first surface so as to provide a reflection pattern.

A method to authenticate a document comprising a first surface and a second surface, in which the first surface comprises a first set of print structures and a second set of print structures, and in which the first set of print structures and the second set of print structures cooperate to obscure a location on the first surface of the second set of print structures, and in which the second set of print structures are arranged on the first surface so as to provide a reflection pattern, said method comprising:

• illuminating the document with energy having a frequency in the range of 50-80 GHz;
• receiving a reflected pattern from the document;
• comparing the reflected pattern or attributes of the reflected pattern to an expected pattern or expected attributes;
• and
• based at least in part on the comparing, determining whether the document is authentic.

An apparatus comprising:

• an optical imager for capturing image or video data associated with a physical object, the physical object comprising a plurality of randomly or pseudo-randomly occurring features, the physical object further comprising indicia provided thereon, the indicia conveying expected characteristics of the features including expected spatial positioning information relative to the physical object;
• a display;
• an electronic processor programmed for:
• analyzing image or video data captured by the optical imager to obtain actual characteristics of the features, the actual characteristics of the features comprising spatial positioning information for the features on the object;
• analyzing the image or video data to obtain the expected characteristics of the features;
• based at least on the expected characteristics and the actual characteristics of the features, providing user feedback via the display corresponding to an expected spatial positioning of the features relative to the object, the user feedback also corresponding to an actual spatial positioning of the features.

A cell phone comprising:

• a camera for capturing image or video data associated with a physical object, the physical object comprising a plurality of randomly or pseudo-randomly occurring features, the physical object further comprising indicia provided thereon, the indicia conveying expected characteristics of the features including expected spatial positioning information relative to the physical object;
• a display;
• an electronic processor programmed for:
• analyzing image or video data captured by the camera to obtain actual characteristics of the features, the actual characteristics of the features comprising spatial positioning information for the features on the object;
• analyzing the image or video data to obtain the expected characteristics of the features;
• based at least on the expected characteristics and the actual characteristics of the features, providing user feedback via the display corresponding to an expected spatial positioning of the features relative to the object, the user feedback also corresponding to an actual spatial positioning of the features.