Laser-phosphor based stage-lighting fixture providing ctt control

Abstract

The invention provides a light generating system () comprising a first light generating arrangement (), a luminescent body (), a reflective polarizer (), and a control system (); wherein the first light generating arrangement () is configured to generate pump light () having a controllable polarization, wherein the polarization is controllable between a first polarization and a second polarization; wherein the first light generating arrangement () comprises a first solid state light source () selected from the group comprising a superluminescent diode and a laser diode; wherein the luminescent body () comprises a luminescent material (); wherein the luminescent body () is configured to (a) transmit at least part of the pump light () (comprising the first polarization and/or the second polarization) and (b) convert at least part of the pump light () (comprising the first polarization and/or the second polarization) into luminescent material light (); wherein the reflective polarizer () is configured downstream of the luminescent body (); wherein the reflective polarizer () is transmissive for at least part of the luminescent material light (); wherein the reflective polarizer () has a higher transmission for the pump light () comprising the first polarization than for the pump light () comprising the second polarization, wherein the reflective polarizer () has a lower reflectivity for the pump light () comprising the first polarization than for the pump light () comprising the second polarization; wherein the light generating system () is configured to generate system light (); and wherein the control system () is configured to control spectral properties of the system light () by controlling the polarization of the pump light ().