a camera tube, more sensitive than the orthicon, in which an electron image generated by a photocathode is focused on one side of a target that is scanned on its other side by a beam of low-velocity electrons to produce the output signal.
an extremely sensitive detector of light and of other radiation, consisting of a tube in which the electrons released by radiation striking a photocathode are accelerated, greatly amplifying the signal obtainable from small quantities of radiation.
