This invention provides a fiber optic rotary joint (20) for enabling the transmission of digital optical signals across the interface between facing surfaces (26, 29) of a rotor and a stator (21, 22), comprising: a plurality of light sources (42A, 42B, 42C, . . . ) mounted on one of the rotor and stator, each light source including a first light source (43C) arranged to selectively generate a first optical signal at a first wave length and a second light source (43C) arranged to selectively generate a second optical signal at a second wavelength； a first plurality of light emitters (25) spaced along a first arc distance of the surface of the one of the rotor and stator for transmitting optical signals received from the light sources toward the facing surface of the other of the rotor and stator； a first plurality of first optical fibers severally communicating respective ones of the light sources with respective ones of the light emitters for conveying optical signals from each respective light source to the associated emitter； a second plurality of light receptors (31) spaced along a second arc distance on the surface of the other of the rotor and stator； and at least one light detector (36, 40) mounted on the other of the rotor and stator； and a second plurality of second optical fibers severally communicating respective ones of the light receptors with the light detector(s).L'invention concerne un joint tournant pour fibres optiques (20), destiné à permettre la transmission de signaux optiques numériques sur l'interface entre des surfaces opposées (26, 29) d'un rotor et d'un stator (21, 22) et comprenant : une pluralité de sources lumineuses (42A, 42B, 42C...) montées sur le rotor ou le stator, chaque source lumineuse comprenant une première source lumineuse (43C) conçue pour générer sélectivement un premier signal optique à une première longueur d'onde et une seconde source lumineuse (43C) conçue pour générer sélectivement un second signal optique à une seconde
