EMC Design and Implementation for Image Intensifiers

An image intensifier cannot pass an electromagnetic compatibility (EMC) test because of its weak anti-electromagnetic interference (EMI) ability. Therefore, it is speculated that abnormal phenomena, such as flickering, highlighting, and extinction of the fluorescent screen, similar to that observed in the test results may occur in the complex electromagnetic environment of a battlefield. This will likely interfere with night vision observation ability. To meet EMC requirements, this study first analyzed the EMC design weaknesses of an image intensifier based on EMC test results and determined the key factors affecting EMC. Next, high-frequency filtering, metal shell shielding, and low-impedance grounding were designed accordingly. Finally, the image intensifier was subjected to an anti-radiation interference test in a 200 V/m electric field; results indicated that the image intensifier was stable in the whole frequency range, verifying the acquired anti-EMI ability.