Abstract: An interactive optical transmission system including a transmitter assembly (EE) with a FSK DFB laser (10) and a receiver assembly (ER) having the same type of DFB laser (20) and functioning as a photoreceiver. In order to make this system interactive, the receiver (ER) is provided with a channel selection circuit (40) able to supply a current which will place the laser (20) of the receiver assembly (ER) well above the threshold and make it function as an amplitude shift keyed transmitter. The beam transmitted by said laser (20) will raise the optical transmission line (FO) to the transmitter assembly (EE). An amplitude demodulation (48) will make it possible to restore the selection code and control the appropriate information channel (S).

Abstract: A bidirectional transmission system with identical laser components. The system features two identical assemblies. Each assembly is constituted by a laser structure able to operate as either an emitter or as a receiver. The system thus has a half-duplex operation. Such a system finds particular application to optical communications.