Signal lamps (such as Aldis lamps), are visual signaling devices for optical communication (typically using Morse code). Modern signal lamps are a focused lamp which can produce a pulse of light.OverviewOptical communication, also known as optical telecommunication, is at a distance using to. Visual techniques such as,,, and were the earliest forms of optical communication. Hydraulic telegraph semaphores date back to the 4th century BC. In the present day a variety of electronic systems optically transmit and receive information carried by pulses of light. cables are employed to carry electronic data and telephone traffic.
