Abstract:
Color CRTs, used in large display screens, have a plurality of three color electron beams that are strongly focused so that they crossover and become divergent in both the X and Y axes if the CTR's face. The strength of the focusing determines the size of the illuminated area on the face of the CRT. A shadow mask, aperture grill, or slotted mask and the red, green and blue phosphor dots or stripes are located at predetermined positions such that the red electron beams only hit the red phosphors, the green electron beams only hit the green phosphors, and the blue electron beams only hit the blue phosphors. No raster scanning with the electron beams are required.
Abstract:
A cathode ray tube device has multiple elements for generating a display. Each of the relatively large number of elements has its own electron gun and deflection assembly. A large number of these subunits are connected into a regular array in which each unit generates a portion of the overall display. The individual gun and deflection assemblies are preferably formed in a framework which serves to both align and position the individual assemblies, and further to provide structural support for the evacuated tube.
Abstract:
An evacuated envelope has a rectangular display section and a gun section at one edge of the display section. The display section includes front and back walls which are generally rectangular, in closely spaced, parallel relation, and a plurality of spaced, parallel support walls between the front and back walls forming a plurality of parallel channels. The gun section extends across one end of the channels and includes therein gun structure which will direct electrons into the channels. In each of the channels is a beam guide which confines the electrons in a beam and guides the beam along the length of the channel. The beam guide also includes means for selectively deflecting the electron beam out of the guide at selective points along the guide so that beam will impinge upon a phosphor screen along the inner surface of the front wall. In each of the channels is a scanning deflector which deflects the path of the beam as it passes from the guide to the phosphor screen so that each of the beams will scan a portion of the phosphor screen.
Abstract:
Voltage applied to the grill of a focus-grill, color cathode ray tube is modulated at vertical scanning frequency. When scanning along the top and bottom edge portions of the grill, potential applied to the intermediate portion of the grill is increased, thereby correcting for overfocus in the vicinity of the vertical axis by narrowing the width of the focused electron beam on the screen. This avoids color impurity at the top and bottom regions of the screen. When scanning along the region of the horizontal axis, potential applied to the intermediate portion of the grill is decreased, thereby correcting for underfocus in the vicinity of the vertical axis by narrowing the width of the focused beam and thus avoiding color impurity in that region. The voltage modulations are progressively proportioned or damped by resistor means in directions outwardly toward the left and right edge portions of the grill, to which constant potential is applied. Damping the applied voltage modulation to a constant potential avoids color impurity at the edge portions, which have very high color purity sensitivity to grill voltage change.
Abstract:
In a post focussing type colour picture tube comprising an evacuated envelope including a panel, a funnel and a neck, a fluorescent screen formed on the inner surface of the panel, an electron gun assembly contained in the neck, a colour selection electrode disposed between the electron gun assembly and the fluorescent screen, and a supporting member for supporting the colour selection electrode, the colour selection electrode is electrically insulated from the supporting member and a potential higher than that impressed upon the colour selection electrode is impressed upon the supporting member.