Method of making an output filter for an image intensifier tube with color reproduction and an output made according to this method

Claim 1

The method of making an improved distortion compensated output filter for viewing the image on the anode screen of an image intensifier tube of the type including a cathode, an anode having a white phosphor screen and an input filter through which light is impinged on the cathode, the filter being divided into regularly spaced groups of regions, the regions of each group being adapted to transmit different clors of the spectrum than the colors transmitted by the regions of the other groups, comprising the steps of forming on said anode screen an image of one of said groups of regions only and photographically producing a replica of said formed image depicting the regions of said one group in the color in which they appear in the input filter, repeating said steps for each said color, and superimposing the thus formed replicas, said superimposed replicas thus constituting a reproduction of said input filter modified by the distortions produced within said tube.

Claim 2

The method of making an improved distortion compensated output filter for viewing the image on the anode screen of an image intensifier tube of the type including a cathode, an anode having a white phosphor screen and an input filter through which light is impinged on the cathode, the filter being divided into regularly spaced groups of regions, the regions of each group being adapted to transmit different clors of the spectrum than the colors transmitted by the regions of the other groups, comprising the steps of forming on said anode screen an image of one of said groups of regions only and photographically producing a replica of said formed image depicting the regions of said one group in the color in which they appear in the input filter, repeating said steps for each said color, and superimposing the thus formed replicas, said superimposed replicas thus constituting a reproduction of said input filter modified by the distortions produced within said tube.

Claim 3

The method of making an image intensifier tube including an improved distortion compensated output filter for viewing the image on the anode screen, said image intensifier tube being of the type including a cathode, an anode having a white phosphor screen and an input filter through which light is impinged on the cathode, the filter being divided into regularly spaced groups of regions, the regions of each group being adapted to transmit different colors of the spectrum than the colors transmitted by the regions of the other groups, comprising the steps of providing a mask having a pattern of light passing and light impervious portions corresponding to the regions of a single one of said groups, positioning said mask between said cathode and a light source, thereby exposing said cathode to light passed through said mask, thus to cause the formation on said anode screen of a pattern corresponding to the pattern of said one group modified by the distortions inhering in said tube, thereafter producing a replica of said formed image on said anode screen depicting the regions of said one group in the color in which they appear on said input filter, and thereafter mounting said replica over said anode screen with the regions of said replica in registry with the regions of said image on said screen.

Claim 4

The method of making an image intensifier tube including an improved distortion compensated output filter for viewing the image on the anode screen, said image intensifier tube being of the type including a cathode, an anode having a white phosphor screen and an input filter through which light is impinged on the cathode, the filter being divided into regularly spaced groups of regions, the regions of each group being adapted to transmit different colors of the spectrum than the colors transmitted by the regions of the other groups, comprising the steps of providing a mask having a pattern of light passing and light impervious portions corresponding to the regions of a single one of said groups, positioning said mask between said cathode and a light source, thereby exposing said cathode to light passed through said mask, thus to cause the formation on said anode screen of a pattern corresponding to the pattern of said one group modified by the distortions inhering in said tube, thereafter producing a replica of said formed image on said anode screen depicting the regions of said one group in the color in which they appear on said input filter, and thereafter mounting said replica over said anode screen with the regions of said replica in registry with the regions of said image on said screen.