Protection of a sensor device in a bank note validator from electromagnetic interference or static electricity

摘要

An anti-EMI lens module used In a bank note or bill validating apparatus includes a circuit board 5, which has a plurality of electric recognition devices 51, a grounding device 52 surrounding the electric recognition devices, and a lens holder base 1 mounted on the circuit board 5. The holder base 1 is either coated with a conductive material 4 or is made from conducting material and is electrically connected to the grounding device 52 to form a grounding loop. The grounding loop absorbs and discharges static electricity during operation of the bill acceptor to protect the electric recognition devices against static electricity, radiowave and electromagnetic interference.