Rear Projection tube BURN-IN

Some examples of 4:3 & 16:9 burn-in on rear projection CRTs. Note the outer area that is most white is virgin phosphor that has not worn. The darker inner parts is where the electron beam has struck the phosphors on the insides of the tube to create a picture causing even burn-in over time wearing the phosphors out resulting in a dimmer picture. Tubes for rear and front projectors are driven brighter and get hotter as a result. These tubes are liquid cooled to stop the glass from cracking. The coolant chambers have been removed to give an unhindered look directly at the tube faces.