Patent ID: 8724940

Claim:
A circuit board assembly, comprising: a first circuit board comprising a top surface and a bottom surface opposite to the top surface, the first circuit board defining a number of first through holes passing through the top surface and the bottom surface; a second circuit board electrically connected to the top surface, the second circuit board comprising an upper surface and a lower surface, the lower surface opposite to the upper surface and facing the top surface, the second circuit board defining a number of second through holes and third through holes passing through the upper surface and the lower surface, each third through hole being aligned with a respect one of the first though holes; a first optical transceiver mounted on the upper surface and optically coupled with second through holes; a number of first light wave guides mounted on the top surface and optically coupled with second through holes for transmitting light signals for the first optical transceiver; a second optical transceiver mounted on the upper surface and optically coupled with third through holes; and a number of second light wave guides mounted on the bottom surface and optically coupled with first through holes for transmitting light signals for the second optical transceiver.