In the field of lighting devices comprising two fiber sources of light and a light transport comprising a plurality of second multimode optical fibers, such devices are designed to be installed in intra-operative optical probes requiring a perfectly uniform visible illumination and fluorescence illumination. A lighting device is provided which comprises a single lens disposed between the fiber sources and the input of the light transport and an optical diffuser. A lighting device is also provided which comprises an afocal system disposed between the fiber sources and the input of the light transport and an optical diffuser. An optical fiber coupler or a semi-reflecting plate provides the mixing of the two fiber sources.
