| 摘要 |
PURPOSE: To dispense with the power source of one side, and to reduce the operating cost by transmitting power by light in the case where two-way communication is executed between two devices by using the light. CONSTITUTION: A light source 131 is made to emit the light by a driving circuit 12 as superimposing an AC component to be a signal upon a specified amount of DC to be the power, and this light is sent from a control station 10 to a field station 20 through a light branching/coupling device 113 and space, and this is received through the light branching/coupling device 23 of the field station 20, and signal light is converted into an electric signal by the light receiver 221 of a photoelectric/electro-optic transducer 22, and power light is converted into the power by a light receiver array 223. Besides, the signal from the field station 20 is generated by making the light source 222 emit the light in accordance with information by a control circuit 21. |
