Device with control grid for electrostatographic reproduction of an optical image

A method for converting an optical image into an electrostatic image comprising the steps of:

• charging an apertured photoconductive control grid with a generally uniform charge;
• exposing said control grid to said optical image wherein to dissipate the charge, on said control grid in conformance with the radiation intensity of said optical image;
• modulating passage of electrons through apertures in said control grid in response to the charge distribution remaining on said control grid;
• and
• storing the electrostatic image pattern resulting from modulating the passage of electrons through said apertures onto an array of conductors.

Apparatus for converting an optical image into an electrostatic image comprising:

• sealed housing means, a wall portion of said housing means comprising an array of conductors electrically coupling the interior of said housing means with the exterior of said housing means;
• means for projecting a beam of electrons toward said array;
• means for storing a predetermined electronic charge distribution between said electron projecting means and said array, said charge distribution determining the localized intensity of said electron beam impinging upon said array;
• and
• means for determining said charge distribution in accordance with said optical image.

Apparatus for converting an optical image into an electrostatic image comprising:

• a vacuum tube housing, said housing including a surface comprised of an array of conducting members coupling the interior of said housing with the exterior of said housing;
• at least one electron gun for projecting electrons toward said array of conducting members;
• a control grid located between said array of conducting members and said electron gun, said control grid including a conducting portion bearing a photoconductive layer, said photoconductive layer substantially shielding said conducting surface from electrons projected by said electron gun, said control grid having a multiplicity of apertures therethrough enabling said electrons to pass and impinge on said array of conducting members;
• and
• an optical window in said housing for applying an optical image on said photoconductive portion of said control grid.

A system for producing an electrostatographic reproduction of an optical image comprising:

• means for producing a stored charge distribution determined by an applied optical image;
• means for modulating an electron beam by said stored charge distribution;
• an array of conductors for storing electronic charges produced by said electronic beam;
• said stored electronic charges comprising a latent electrostatic image of said optical image;
• means for producing an image from said latent electrostatic image on a copy sheet;
• and
• means for transferring said latent electrostatic image from said array of conductors to said image producing means.

A method of providing an electrostatic latent image from an optical image in a vacuum tube device comprising the steps of:

• applying said optical image to a charged photosensitive electrode, said applied optical image determining the charge distribution on said photosensitive electrode whereby there is provided a charge distribution in image likeness to said optical image on said electrode;
• modulating a beam of electrons with said charged photosensitive electrode;
• and
• accumulating charges from said modulated electron beam on a multiplicity of conducting elements, said electrode charge distribution producing charges representative of said electrostatic latent image on said conducting elements.