CAMERA TUBE

摘要

1 PHN 9416 A camera tube target which to be scanned on one side by an electron beam comprises a selenium-con-taining vitreous layer also containing tellurium and arsenic. In order to improve the sensitivity and reduce dark current various target characteristics in accordance with the invention, the concentration of at least one of the elements tellurium and arsenic in a first layer portion of the selenium-containing layer on the side to be scanned increases in the direction of thickness towards the side to be scanned to a value at which the sum of the concentrations of tellurium and arsenic on the side to be scanned is at most 30 at.%; the arsenic concentration everywhere in the selenium-con-taining layer exceeds 1.5 at.%; and in a second layer portion adjoining the first layer portion the concentration of at least one of the elements arsenic and tellurium has a minimum value with respect to an adjoining third layer portion. A fourth layer portion may also be present between the third layer portion and the signal electrode, and the concentration of arsenic and/ or tellurium in the third layer portion may have a maximum value with respect to the fourth layer portion.