| 摘要 |
<p>A reading apparatus (10) of an optical data carrier (1) bearing a first (2) and a second (3) diffractive structure obtained on overlapped levels, wherein the second structure (3) bears an information diffractive code and the first structure (2) bears a control diffractive code apt to act as a read key for said information code, the construction being such that, when the data carrier (1) is exposed to a substantially monochromatic beam of electromagnetic waves, each structure deviates such incident beam into one or more diffracted beams spatially independent from the one or more diffracted beams originated by the other structure, which apparatus (10) comprises:
- An emitting unit (11), apt to emit a substantially monochromatic beam of electromagnetic waves apt to be deviated by the diffractive structures;
- A first detecting unit (12), for detecting the control code of the first diffractive structure (2) of the data carrier (1), comprising first detecting means;
- A second detecting unit (13), for detecting the information code of the other diffractive structure (3) of the data carrier (1), comprising second detecting means arranged at a position distinct from that of the first detecting means;
- a processing unit (15), apt to verify the authenticity of the data carrier (1) according to the detections of said detecting units (12, 13); and
- means (150) selectively programmable with at least one position parameter related to a linear and/or angular position of the first diffractive structure (2) and at least one application parameter representative of the specific application of the data carrier (1) bearing the diffractive structures (2, 3) ( Fig. 2 ).</p> |
