Method for encoding and decoding data by varying the distinctive characteristics of an optical radiation, encoding device and decoding system

A data ciphering method, said method comprising:

• a step of generating a localised alteration pattern of one or more selected areas of an encoding element at least selectively transparent to luminous, infrared or ultraviolet radiation;
• a step of processing said encoding element at least selectively transparent to luminous, infrared or ultraviolet radiation, wherein in said step of processing the selected areas of said at least selectively transparent encoding element are selectively altered according to said localised alteration pattern, and wherein, with said selective alteration of said selected areas is varied a distinctive characteristic of an optical radiation incident and passing through said encoding element,
• said step of processing leading to a permanent modification of the characteristic of said element such to obtain a storing of a ciphered message or a ciphering key for an unencrypted message;
• and
• a step of irradiating said encoding element with a luminous, infrared or ultraviolet radiation incident on said encoding element at a first input surface, so that this optical radiation passes in the encoding element through at least one of said areas, up to a second output surface.

A method of deciphering data contained in a ciphered message, said method comprising:

• a step of arranging an encoding element having a plurality of areas with a varied distinctive characteristic of an incident optical radiation and/or varying a distinctive characteristic of an optical radiation incident thereon, wherein said varied distinctive characteristic of an incident optical radiation is previously defined based on a localised alteration pattern of said element with a biunivocal association with a ciphering key of an unencrypted message on a known cyphering function, in correspondence of a source of a luminous, ultraviolet or infrared optical radiation, in a position such that said optical radiation, by being incident on the surface of said encoding element, passes through said plurality of areas with a varied distinctive characteristic of incident optical radiation, producing in output of said encoding element a message ciphered under electromagnetic radiation;
• a step of arranging at least one photoreceiver in a direction for propagating said radiation through said encoding element, wherein said photoreceiver element is configured so as to directly or indirectly perceive at least one variation of the distinctive characteristic of said radiation at said areas with a varied distinctive characteristic of an incident optical radiation and/or varying a distinctive characteristic of an optical radiation incident thereon;
• and
• a step of extracting information from the radiation exiting from said encoding element based on a reconstruction of said alteration.