| 摘要 |
PROBLEM TO BE SOLVED: To prolong the service life of a battery for portable equipment by reducing the power consumption required for optical communication and to reduce interference and impairment to another spatial optical communication. SOLUTION: In a light emitting element 17 of a transmission part 13 of a first transmitter-receiver 10, light emission driving is controlled by a light emission drive control circuit 12, and the intensity of emitted light is adjusted by an emitted light intensity adjusting circuit 18 inside the light emission drive control circuit 12. The intensity of received light at a light receiving element 27 of a reception part 24 of a second transmitter-receiver 20 is detected by a received light intensity detection circuit 28 inside an optical signal reception processing circuit 25, sent out through a transmission driving control circuit 22 and a transmission part 23 to be received at a reception part 14 of the first transmitter-receiver 14, and this received light intensity information is fetched by a reception processing circuit 15 and sent to the emitted light intensity adjusting circuit 18. In accordance with this received light intensity information, the emitted light intensity adjusting circuit 18 adjusts the light emitting element 17 into irreducibly minimum emitted light intensity capable of executing a stable optical communication. |
