Patent ID: 7498939

Claim:
A communication system for performing two-way wireless data communication between devices, the communication system comprising: a child unit; and a parent unit operable to communicate with the child unit; the child unit including: a power switch for turning power to the child unit on/off; a signal generator operable to issue a power control signal for turning power to the parent unit on/off in response to turning the power switch on/off; and a first data communication unit operable to carry out two-way wireless data communications with the parent unit; and the parent unit including: a receiving unit operable to receive the power control signal from the signal generator of the child unit; a power controller operable to turn power to the parent unit on/off in response to reception of the power control signal from the receiving unit; and a second data communication unit operable to carry out two-way wireless data communications with the child unit, wherein the signal generator of the child unit includes an interlock switch that is actuated in response to operation of the power switch, and a light emitting unit operable to emit the power control signal as infrared light in response to actuation of the interlock switch; and the receiving unit of the parent unit includes a light receiving unit operable to receive the power control signal as infrared light from the child unit.