PURPOSE: To provide an X-ray image tube capable of improving the resolution with a simple structure.
CONSTITUTION: Discontinuous phosphor layers 12 of discontinuous cesium iodide are formed in the face direction on an aluminum substrate 11, and a continuous phosphor layer 13 of cesium is laminated on the discontinuous phosphor layers 12 to form an input fluorescent screen 14. The thickness of the discontinuous phosphor layers 12 is made thinner at the peripheral section of the input fluorescent screen 14 than at the center section. The light absorption quantity is changed at the peripheral portion having less light quantity due to the difference of thickness from the center section of the input fluorescent screen 14, thus the change of intensity is small between the center section and the peripheral section. The interval between fiber bodies 12a is set to 0.5μm or above, oxygen easily infiltrates between the fiber bodies 12a, and oxide films are easily formed. The diameter of the fiber bodies 12a is made 40μm or below, thus oxide films can be easily formed around columnar crystals via small movement.
KUBO HIROSHI
TORITANI ATSUSHI
