  Noble gases and liquids are excellent scintillators and this opens a unique
opportunity to directly detect the primary scintillation light produced in
these media by photons or particles. This signal can be used for several
purposes, for example as a start signal for TPCs or for particles
identification. Usually photomultipliers (PMs) are used for the detection of
the scintillation light. In our previous work we have demonstrated that costly
PMs could be replaced by gaseous detectors with CsI photocathodes . Such
detectors have the same quantum efficiency as the best PMs but at the same time
are cheap, simple and have high position and time resolutions. The aim of this
work is to evaluate various planar type gaseous detectors with CsI photocahodes
in order to choose the best one for the detection of the primary scintillation
light from noble gases and liquids.
