FORMATION OF FLUORESCENT SCREEN FOR COLOR PICTURE TUBE

• Main Author: MAEDA SHIYOUICHI
• Format: Patent
• Language: English
• Published: 18.05.1983
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY

PURPOSE:To prevent any generation of beam-landing shifts such as rotary asymmetries, without using any expensive lens with a complicated curved surface, by locating the horizontal axis of the second optical lens on an axial line which slants from a reference horizontal axis, which is parallel to the horizontal axis of a face panel, by a rotation angle, theta. CONSTITUTION:The horizontal axis (H-H') (extending in the sectional direction of a curvature radius, Rx) of the second optical lens 6 is not located on a reference horizontal axis (X-X') which is parallel to the horizontal axis of a face panel, and is located on an axial line which slants from the axis (X-X') by a rotation angle (theta). By locating the optical lens 6 as mentioned above, light which is incident upon the corners of the first quadrant (the upper right area) and the third quadrant (the lower left area) after passing through the lens, and light which is incident upon the second quadrant (the lower right area) and the fourth quadrant (the upper left area) are deflected according to the rotation angle (theta). As a result, phosphor dots baked by being exposed to such light as above, are shifted in directions indicated by the arrows. The degree of above deflection can be controlled by varying the rotation angle (theta).