Multi-beam group electron gun for color CRT

A G1 control grid for a color cathode ray tube (CRT) adapted to receive energetic electrons from a cathode and to form said energetic electrons into a plurality of electron beams for horizontal displacement over a plurality of scan lines in a raster-like manner across a display screen of said CRT in forming a video image on said screen, said grid comprising:

• first, second and third horizontally aligned upper conductive portions each adapted for coupling to a respective first video signal source;
• first, second and third horizontally aligned lower conductive portions each adapted for coupling to a respective second video signal source;
• insulating means disposed intermediate adjacent conductive portions for electrically isolating said conductive portions;
• means for defining first, second and third horizontally aligned upper apertures each disposed within a respective one of said upper conductive portions, wherein each of said upper apertures passes a respective upper electron beam forming one of the primary colors of red, green and blue of a video image on the display screen and wherein said upper electron beams are horizontally displaced over a first upper scan line;
• and
• first, second and third horizontally aligned lower apertures each disposed within a respective one said lower conductive portions, wherein each of said lower apertures passes a respective lower electron beam forming one of the primary colors of red, green and blue of a video image on the display screen, and wherein said lower electron beams are horizontally displaced over a second, adjacent lower scan line, and wherein each pair of first, second and third upper and lower apertures are vertically aligned and pass electron beams forming the same primary color on the display screen.

An inline electron gun for a multi-beam color cathode ray tube (CRT) including a display screen whereon a video image is formed by sweeping a plurality of horizontally aligned electron beams over a plurality of vertically spaced, horizontal scan lines in a raster-like manner, wherein each electron beam provides one of the three primary colors of red, green or blue of the video image, said electron gun comprising:

• a plurality of cathodes including a first upper array of horizontally aligned, spaced cathodes and a second lower array of horizontally aligned, spaced cathodes;
• a beam forming region (BFR) disposed adjacent to said cathode means and including first and second spaced, charged, grids respectively having first and second arrays of spaced apertures for forming the energetic electrons into a plurality of beams, wherein each of said first and second arrays of apertures include upper and lower horizontally aligned apertures for passing horizontally aligned electron beams providing the three primary colors of red, green and blue for upper and lower horizontal scan lines, respectively, and wherein the apertures in said first and second arrays are further grouped in vertical alignment so as to form vertically grouped electron beams with the electron beams in each vertical group providing one of the primary colors on a respective horizontal scan line, and wherein each of the cathodes in said first upper and second lower arrays is disposed in closely spaced relation to a respective one of said upper and lower horizontally aligned apertures in said first grid such that energetic electrons from only one of said cathodes reaches each aperture in said first array of apertures;
• lens means disposed intermediate said BFR and the CRT's display screen for focusing the electron beams on the display screen;
• and
• convergence means disposed intermediate said lens means and the display screen for converging the electron beams into an upper and a lower spot on the display screen, wherein said upper and lower spots are swept over adjacent upper and lower horizontal scan lines, respectively.