Abstract: In a system of optical communications that can be used by air or space vehicles, each station comprises at least one optical system covering a half space, this system comprising two twinned optical devices to respectively form two distinct reception channels: a first reception optical channel for the initialization, in space, of the direction of communication; a second optical channel for the reception of the contents of the communication. One of the two optical devices is also used to form a transmission channel for the initialization and then for the communication in the direction of communication. The setting up of communication is done in three steps, respectively target designation, iterative bilateral acquisition and interstation communication.