Radiation detecting device insensitive to high magnetic fields.

摘要

There is disclosed a phototube (11) comprising a closed container having a light permeable face plate (12a) the outside surface of which is a light incident surface, a photocathode (13) so provided in the closed container that at least a part of a photo-electric surface is inclined to the light incident surface, and an anode (14) so provided in the closed container that an electron capturing surface is opposed to the photo-electric surface in parallelism therewith. <IMAGE>