on opposite sides of screen, e.g. for conversion of definition

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 > Tubes for storage of image or information pattern or for conversion of definition of television or like images, i.e. having electrical input and electrical output > having means for deflecting, either selectively or sequentially, an electron ray on to separate surface elements of the screen (by circuitry alone H01J29/08) > with separate reading and writing rays > on opposite sides of screen, e.g. for conversion of definition