Lighting unit comprising a waveguide

A lighting unit comprising (a) a waveguide, the waveguide comprising a first light exit surface, a second light exit surface configured opposite of the first light exit surface, and an edge, the lighting unit further comprising (b) a light source, configured for lighting the waveguide (100) with light source light, thereby providing incoupled light source light within the waveguide, wherein the lighting unit is further configured to allow part of the incoupled light source light escape from the waveguide at one or more of the first light exit surface and the second light exit surface as outcoupled light source light, wherein the lighting unit further comprises (c) one or more of a first luminescent material adjacent to the first light exit surface and configured to provide first luminescent material light, and a second luminescent material adjacent to the second light exit surface and configured to provide second luminescent material light, wherein the first luminescent material and the second luminescent material are excitable by the outcoupled light source light, wherein the lighting unit is configured to provide during operation first light emanating from the lighting unit in a direction away from the first light exit surface and second light emanating from the lighting unit in a direction away from the second light exit surface, the first light comprising contributions of one or more of (i) the outcoupled light source light and (ii) one or more of the first luminescent material light and the second luminescent material light, the second light comprising contributions of one or more of (iii) the outcoupled light source light and (iv) one or more of the first luminescent material light and the second luminescent material light, the first light having a first spectral distribution, the second light having a second spectral distribution, wherein the first spectral distribution and second spectral distribution differ, wherein the lighting unit further comprises one or more of a plurality of first reflectors and a plurality of second reflectors.