Investigation of the degradation of electron-beam-tube laser screens

An investigation was made of the fast phase in the progressive degradation of laser screens in a laser electronbeam tube. Degradation of the output power from a laser screen was studied as a function of the pumping rate, excitation frequency, and scanning rate. From a consideration of the possible reasons for degradation it was concluded that the decisive factor is the growth in the density of dislocations caused by thermoelastic stresses which appear in the laser screen when it is excited with an electron beam. It was shown that the service life of a laser screen operating in the television mode can reach several thousand hours.