Patent ID: 7551101

Claim:
A light emitting device drive controller comprising: 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.