Phosphor Non-Linearities In Picosecond Streak Cameras

Phosphor nonlinearities in streak cameras are evaluated by experimental photometric calibration of streak tubes and other image intensifiers by using optical pulses of duration 100ps, 10 ns amd 10 ms. The results confirm that there is a serious loss of efficiency of the phosphor when excited by electron pulses of duration 10 ns or shorter. P-11 phosphors showed an efficiency of 1.85% at 100 ps while P-20 phosphor showed 1.2% efficiency at the same temporal excitation. At 10 ms excitation, the efficiencies were 7.41% and 7.47% respectively. The phosphor efficiencies for short pulse excitation remained unaltered at this low value for intensity levels ranging over four decades.