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

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 localized 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.