The document summarizes the Trinitron tube technology developed by Sony in the 1970s. It has a single electron gun with three vertically-aligned cathodes that emit beams towards an aperture grille. The grille has vertical slots that allow the beams to pass through and strike their corresponding colored phosphor stripes on the screen. This design improves vertical resolution and focus, provides sharper pictures, and eliminates convergence issues compared to other CRT technologies. The single gun is also easier to construct and align than multi-gun designs.