An optical rotary joint comprises a first collimator arrangement for coupling-on first light-waveguides and a second collimator arrangement for coupling-on second light-waveguides, with the second collimator arrangement being supported to be rotatable relative to the first collimator arrangement about a rotation axis. A Dove prism is provided between the collimator arrangements as a derotating element. An intermediate layer is provided on at least one boundary face of an optical constituent part to a surrounding medium, which the intermediate layer comprises a nano-structure having a mean refractive index lying between a refractive index of a material of the optical constituent part and a refractive index of the medium of the surroundings.