Abstract: An X-ray image intensifier includes an input screen. The input screen has a base plate, a phosphor layer formed on the base plate, a transparent conductive film formed on the phosphor layer, and a photoemissive layer formed on the conductive film. The conductive film has a crystallinity wherein an average crystal size along a direction parallel to a surface of the conductive film is 500 .ANG. or more.

Abstract: In a radiographic method, first and second collimator elements are arranged between a radiation source and an image converter. When an object is irradiated with radiation beams, the collimatar elements can be switched between first and second states. In the first state, the collimator elements pass both some of the transmitted radiation beams which are not scattered by the object and transmitted therethrough and scattered radiation beams which are scattered by the object so that a first radiation image is obtained in the form of electrical signals based on the transmitted radiation beams and the scattered radiation beams. In the second state, the collimator elements pass only some of the scattered radiation beams scattered by the object so that a second radiation image is obtained in the form of electrical signals based on only the scattered radiation beams.

Abstract: An image intensifier has a phosphor screen, the phosphor screen having a mesh-like substrate and a phosphor layer supported by the mesh-like substrate and to be excited by electron rays. The image intensifier provides an output image with high contrast and brightness.