| 摘要 |
PROBLEM TO BE SOLVED: To stably execute optical communication when optically communicating with an external terminal at an optical communication distance within a prescribed range by controlling a light emitting element so as to convert communication data to an optical communication signal of a light emitting intensity corresponding to the intensity of surrounding diffused external light based on a light emitting element control signal. SOLUTION: An infrared state signal generating part 4 measures the absorbing quantity of surrounding infrared light and generates an infrared state signal showing the state of the infrared light based on the absorbing quantity of the infrared light. A light emitting element control signal generating part 5 generates a light emitting element control signal for controlling the light emitting intensity of plural light emitting elements 2-1 based on a diffused external light state signal outputted from a diffused external light state signal generation part 3 and the infrared state signal outputted from the part 4. A light emitting element control part 6 controls the plural elements 2-1 so as to convert communication data to an optical communication signal of light emitting intensity corresponding to surrounding diffused external light based on the light emitting element control signal. |
