| 摘要 |
The system comprises a device for revelation of powerful microwave radiation exposure of a microcircuit. The device comprises a unit, which is sensitive to an elevation of temperature of a predefined area in a valuable document (10), and an antenna circuit comprising an antenna element significantly tunes in microwave radiation and a charge that partially extends in the predefined area, is connected to the antenna element and is capable of heating when it is crossed by a stream. The antenna element comprises a first part of antenna to capture an electrical component in microwave radiation. The system comprises a device for revelation of powerful microwave radiation exposure of a microcircuit. The device comprises a unit, which is sensitive to an elevation of temperature of a predefined area in a valuable document (10), and an antenna circuit comprising an antenna element significantly tunes in microwave radiation and a charge that partially extends in the predefined area, is connected to the antenna element and is capable of heating when it is crossed by a stream. The antenna element comprises a first part of antenna arranged to capture an electrical component in microwave radiation, and a second part of antenna arranged to capture a magnetic component from the radiation, where the first part of the antenna is a dipole antenna and second part of antenna is a magnetic loop antenna. The first antenna part comprises two electrically conducting branches separated by a dielectric, and the second antenna part comprises electrically conductive coils. The dipole antenna has a length, which is less than half of the wavelength of microwave radiation. The antenna circuit further comprises an interface for mutually coupling the first and second parts. The coupling interface comprises an electrically conductive element connected to the first part of the antenna and partially connected to the second part of the antenna. The antenna element is made by screen printing with electrically conductive ink. The sensitive unit is arranged to undergo a detectable transformation under the effect of an elevated temperature, and comprises a color changing substance passing from a first stable state to a second stable state by chemical reaction triggered by the microwave radiation, where the reaction is to be rendered effectively and completely by raising the temperature. The second part of antenna is connected to the charge. The first and second parts of the antenna are sized to carry out an impedance matching. The microcircuit is inoperative by exposure to the microwave radiation of a predefined power of greater than 50W and a preset time of 0.1-10 seconds. An independent claim is included for a valuable document. |
