Description

The author proposes to base the synthetic reproduction of the television picture upon the optical and physiological actions of the motion picture projector of Mechau. This idea rests up on the high amount of correlation existing between the sequential images and on the inert visual perception of man, i. e. two facts which favour the introduction of an electrostatic memory device capable of modulating on each picture point its instantaneous brightness. In this system the whole number of surface elements of the screen stays simultaneously excited without any interruption of their appearance thereby suppressing the flicker and permitting a lower scanning rate with a corresponding reduction of the frequency band needed for the trans- mission of the picture signa!. Alike the Mechau-projector the frames follow each other in continuous superposition and progressive translucency along their succession. This impression is aided by a special form of interlacing line fields written down on the memory device. The picture is restored by a tube having a mosaic-like UV lighted photocathode which permits the loc al command of its emission to be projected on the screen without geo- metrie distortion. The principle described fits also for colour television. Résumé L'auteur propose d'appliquer à la synthèse de l'image de télévision les effets optiques et physiologiques du projecteur de cinéma M echau.