| 摘要 |
A system for preventing unsanctionned switching comprises a switch consisting of a holographic device (1) with a coded hologram recorded in its light-sensitive layer (2), and a means for identification of the switch mounted relatively to the identification means. The identification means comprises a casing (3), a radiation source (4) for illumination of the holographic device (1), a photodetector (5) intended for registration of the radiation coming from the holographic device (1), and an analyser (6) of the level of signals of the photodetector (5). The analyser has a threshold recognition level and is intended for generation of the switching signal at its output if the code recorded in the hologram of the holographic device (1) corresponds to the code of the identification means, which consists of the output signal of the photodetector (5). The latter comprises at least one main photoelement (5b) located within the zone of generation, by the switch, of the coded holographic image with an illumination intensity providing at the output of said photoelement (5b) a signal whose level exceeds the threshold recognition level of the analyser. |
