| 摘要 |
PURPOSE:To reduce the coarseness of a screen by arranging an optical unit whose panel surface of a cathode-ray tube is coated with the first and second transparent bodies with different refractive indexes so that the logitudinal direction of a phosphor stripe can differ from the direction of a prism. CONSTITUTION:The panel 2 surface of a cathode-ray tube is coated with the first transparent body 3, for example, made is ''Rigolacs '' resin and is also coated with the second transparent body 4, for example, made of acrylic resin through this transparent body 3. A number of mutually parallel triangular grooves are provided on the inside surface of the second transparent body 4 and a boundary surface 5 with a triangular wave-shaped cross section is formed between the first and second transparent bodies 3 and 4. On the boundary surface 5, a pair of refracted surfaces 8 are mutually intersected repeatedly at a preset angle and a prism 7 is formed integratedly. Besides, the longitudinal direction of the prism 7 consisting of the first and second transparent bodies 3 and 4 has an angle psi to the longitudinal direction of the respective color phosphor stripes R, B, and G. |
