having grid-like image screen through which the electron ray or beam passes and by which the ray or beam is influenced before striking the luminescent output screen, i.e. having "triode action"

Full Title

Cathode ray tubes; Electron beam tubes (H01J25/00, H01J33/00, H01J35/00, H01J37/00 take precedence; details of cathode ray tubes or of electron beam tubes H01J29/00) > having a screen on or from which an image or pattern is formed, picked up, converted, or stored > Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output > having grid-like image screen through which the electron ray or beam passes and by which the ray or beam is influenced before striking the luminescent output screen, i.e. having "triode action"