A communication system includes: at least one light-emitting device for emitting a light; and at least one light-receiving device for receiving the light emitted from the at least one light-emitting device. The light-emitting device further includes: at least one driver unit for generating a modified current based on an externally entered information signal; and at least one light-emitting unit operatively and functionally coupled to the at least one driver unit for receiving the modified current and emitting a modified signal light including any information based on the modified current. The at least one light-emitting unit includes at least one electroluminescence element.