Electromagnetic shielding of plastic packaging in low-cost laser modules

Low-cost MiniDIP laser modules fabricated by plastic moulded technology filled with highly conductive materials are proposed for the evaluation of electromagnetic interference (EMI) shielding effectiveness (SE). The SE of conductive plastics was measured to be 45 dB at 30 MHz and 62 dB at 1 GHz. The laser modules have a transmission speed up to 622 Mbit/s and > 1 mW fibre output power. With these excellent SEs and good optical characteristics, such plastic MiniDIP laser modules are suitable for use in low-cost OC-12 lightwave transmission systems.