Provided is a control apparatus for an internal combustion engine, which quietly restarts the engine with a reduced torque shock when a re-acceleration request is made by a driver. A direct current -balanced 6B8B transmission code is produced from an input data stream that includes one or more six-bit source vectors. Each of the first and second polarized components is fed into a first polarization-sensitive deflector and a second polarization-sensitive deflector, each of which deflects a light beam by a predetermined angle.