The invention provides a lighting device (1) comprising (i) a plurality of sets (310) of each one or more light sources (10) configured to provide light source light (11), and (ii) a plurality of luminescent elements (5), each luminescent element (5) comprising an elongated luminescent body (100) having a radiation input face (111) for receipt of the light source light (11), each luminescent element (5) comprising a luminescent material (120) for conversion of at least part of the light source light (11) into luminescent material light (8), and each luminescent element (5) have an luminescent element exit window (12) for the luminescent material light (8); wherein the luminescent elements (5) are configured in a configuration wherein an average distance (d1) between neighboring luminescent bodies (100) is larger than a shortest luminescent element exit window distance (d2) between the neighboring luminescent element exit windows (12), thereby defining an interspace (320) between the neighboring luminescent bodies (100).