EMI screening covers (shielding cans) for PCB's were developed to shield only certain parts of electronic equipment from electromagnetic radiation at the source, rather than all of the components in the entire housing.
ກວດ EMI ການປົກຫຸ້ມຂອງ (cans ປິດບັງ) ສໍາລັບ PCB ໄດ້ຖືກພັດທະນາເພື່ອປົກປ້ອງພຽງແຕ່ບາງສ່ວນຂອງອຸປະກອນເອເລັກໂຕຣນິກຈາກ radiation ໄຟຟ້າທີ່ແຫລ່ງກໍາເນີດ, ແທນທີ່ຈະກ່ວາທັງຫມົດຂອງອົງປະກອບໃນການທີ່ພັກອາໄສທັງຫມົດ.