| 摘要 |
PURPOSE:To improve the contrast characteristics of fluorescent screen by removing part of the core material in the light emitting surface of the fiber plate consisting a fluorescent screen, then coating the entire light emitting surface except the upper surface areas of the core material with light-absorbing layers. CONSTITUTION:A radiation-image intensifier or a similar member is made by installing a phosphor layer 7, an input screen 2 having a photoelectric surface 8 and an output screen 4 having an output phosphor layer 10 in a vacuum envelope 1. The output screen 4 is made by forming a phosphor layer 10 on the light incidence surface 35 of a fiber plate 11 and removing part of the core material 31 existing in the light emitting surface 34 of the fiber plate 11 by selective etching or a similar method to form concaves 42 before the entire light emitting surface 34 except the upper surface areas 44 of the core material 31 is coated with light-absorbing layers 43; the fiber plate 11 has a cross section consisting of a core material 31 forming main light-transmitting areas, a coating material 32 and an absorber 33. As a result, areas of emittion can be restricted only to the upper surface areas 44 of the core material 31 and the influence of multiple inpacts of light which might be caused by internal scattering is prevented, thereby improving the contrast characteristics. |
