The projection system 1, wherein the active cooling arrangement comprises a fan, and the controller controls a speed of {HEAD ~ the fan}, varying an amount of {TAIL ~ air flow} the fan drives pass the solid state light source 
The projection system 1 , wherein the active cooling arrangement comprises a fan , and the controller controls a speed of { HEAD ~ the fan } , varying an amount of { TAIL ~ air flow } the fan drives pass the solid state light source
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH