New developments in multiplier phototubes for space research.

Recent developments in ruggedized high-performance multiplier phototubes are described for the uv and visible. The spectral radiant responses of photocathodes with peak quantum efficiencies up to 30% and higher are detailed over the applicable spectral regions. Photoemissive surfaces with two types of spectral responses are included: (a) spectrally selective cathodes of the extreme solar-blind type for the far uv, and (b) cathodes with broad-band sensitivity over wide spectral ranges. The characteristics of dark current (dc and pulse counting), current amplification, equivalent noise input, and environmental conditions are reviewed for the various new tube types covered.