Abstract: A shielded clear glass cathode substrate (44) is provided for use in an image intensifier tube of the type utilizing a clear glass cathode substrate (46). A black glass cathode substrate shield (48) is coextensive with the entire longitudinal surface of the clear glass cathode substrate (46). The black glass forming the black glass cathode substrate shield (48) has an index of refraction that is greater than the index of refraction of the clear glass utilized in the clear glass cathode substrate (46). A method is provided for producing a shielded glass cathode substrate from a mass of clear glass (52).

Abstract: A photocathode internally processed image intensifier inverter tube includes a cathode housing having an outer side wall forming a cylindrical opening for connection to the photocathode of the inverter tube. The side wall forms a cylindrical cavity in which the phototcathode is received. A pair of flat wall surfaces are formed in the side wall. The flat surfaces are spaced radially inwardly such that the distance from the surfaces to the center of the cylindrical opening is less than the radius of the cylindrical opening. A tubular processing side arm is attached from each flat wall surface and is used to introduce antimony and alkali metal vapor, under a vacuum into the cathode housing for the deposit of a photosensitive coating on the photocathode substrate. After forming the photosensitive surface, the side arms are sealingly pinched off at the ends thereof to maintain a vacuum inside the inverter tube.

Abstract: A photocathode internally processed image intensifier inverter tube includes a cathode housing having an outer side wall forming a cylindrical opening for connection to the photocathode of the inverter tube. The side wall forms a cylindrical cavity in which the photocathode is received. A pair of flat wall surfaces are formed in the side wall. The flat surfaces are spaced radially inwardly such that the distance from the surfaces to the center of the cylindrical opening is less than the radius of the cylindrical opening. A tubular processing side arm is attached from each flat wall surface and are used to introduce antimony and alkali metal vapor, under a vacuum into the cathode housing for the deposit of a photosensitive coating on the photocathode substrate. After forming the photosensitive surface, the side arms are sealingly pinched off at the ends thereof to maintain a vacuum inside the inverter tube.