The reflected-beam kinescope

The reflected-beam kinescope is a display device capable of being made very short, particularly in sizes of 21" and larger. It retains the conventional electron gun and external deflection components and is axially symmetric. Although the effective deflection angle is nearly 180°, the deflection power required is equivalent to that used in conventional 90° kinescopes. The spherically curved tube face has a transparent conductive coating on the vacuum side that is operated at cathode potential and serves to reflect the electron beam. Mounted at a distance from the reflector is a similarly curved structure at high potential, on the convex side of which is deposited the phosphor screen. For television type displays this structure contains an array of very fine holes through which the electron beam passes in its transit from the electron gun to the screen. After reflection at the faceplate the beam falls back to the apertured structure and strikes the phosphor that lies on the surface between the holes. For a radial type scan a factor of four in brightness may be gained by replacing the perforated screen by a solid structure having a small cutout in the center to permit free passage of the beam.