A light emitting device drive controller is disclosed that comprises a
first port that is connected to one end of a first light emitting device
group where two light emitting devices are connected in parallel in the
opposite directions; a second port that is connected to the other end of
the first light emitting device group as well as connected to one end of
a second light emitting device group where two light emitting devices are
connected in parallel in the opposite directions; a third port that is
connected to the other end of the second light emitting device group; and
a port state setting unit that selectively sets each of the first,
second, and third ports to any one of a state of a first voltage, a state
of a second voltage which is less than the first voltage, and a high
impedance state for each consecutive predetermined period, wherein the
light emitting device drive controller drives selectively the light
emitting devices constituting the first light emitting device group and
the second light emitting device group in response to the states of the
first, second, and third ports.