JPS59121733A - Manufacture of input surface of x-ray image tube - Google Patents

Abstract

PURPOSE:To prevent lateral diffusion of light within a phoshor film by filling the prismatic crystal particle boundary or crack of prismatic crystal forming a vacuum-deposited film with a substance having a high light reflectivity or high light absorption coefficient in the powder condition. CONSTITUTION:The crystal particle boundary or crack 25 of prismatic crystal 24 forming a vacuum-deposited film 22 is filled with a substance having a high light reflectivity or light absorbing coefficient in the powder condition in the mean particle size of 1deltam or less. As a substance having a high reflectivity, aluminium, magnesium and silver, for example, are used, while as a substance having a high light absorbing coefficient, carbon, chromium oxide, nickel oxide and iron oxide, for example, are used. Thereby, each prismatic crystal 24 works each other like an independent optical fiber and thereby it can almost perfectly be prevented that the light in the one column invades into the adjacent columns. As a result, total image quality including resolution and contrast can be further improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an X-ray image tube input surface.

As shown in Figure 1, the structure of the X-ray image tube is shown in Figure 1. an input surface Q that emits the optical image as a corresponding photoelectron stream;
In addition to the proverb, focusing electrode (to), anode 0 → output fluorescent surface 0 →
It is composed of etc. An example of the input surface 0 is shown in Figure 2, where the substrate 12ρ is made of an aluminum plate that hardly absorbs X-rays, and a fluorescent film (a) and a photoelectric film (to) are coated on this. It is formed by Recently, as a method for forming a fluorescent film (a), a C8 film containing Na as an active substance is used, and this is applied to a substrate 0.
It is widely practiced to apply the coating to the zero surface by vacuum evaporation method. In this method, the substrate G! A phosphorescent surface having a columnar crystal structure can be formed on a substrate 0υ by applying an appropriate surface treatment to ◇ and appropriately setting the temperature, vapor deposition rate, etc. during vapor deposition. According to the method of forming the input phosphor surface with a C5I (Na-side vacuum distilled film), the phosphor film becomes more difficult to form than the phosphor film formed by coating ZnCclS particle phosphor. This invention greatly reduces the scattering of light in the lateral direction, making it possible to significantly improve resolution.
A further object of the present invention is to provide a method for manufacturing an input surface of an X-ray image tube that can more effectively prevent lateral diffusion of light within the fluorescent film than conventional methods.

Hereinafter, the configuration and embodiments of the present invention will be described with reference to FIG.

This invention consists of forming a CBI (Na) phosphor vacuum-deposited film (e) on the substrate & ]) 1-1 forming a photoelectric film α on the vacuum-deposited film (a); In the production method, a substance with high light reflectance or high light absorption is added to the grain boundaries or cracks of each columnar crystal forming the vacuum-deposited MC'A in a powder state with an average particle diameter of 171 m or less. Characterized by filling.

The materials used as fillers with high light reflectance include aluminum, magnesium, silver, etc., and the materials with high light absorption include carbon, carbon, etc.
Chromium oxide, nickel oxide, iron oxide, etc. are used.
゜This is to prevent the diffusion of light in the lateral direction within the fluorescent film when these substances are filled in the grain boundaries or holes of each columnar crystal. (2) act like mutually independent optical fibers, making it possible to almost completely prevent light emitted from one compartment from invading adjacent compartments. Since the width of the grain boundary or crack (A) of each columnar crystal (2) is approximately several μIn, it may be embedded in the grain boundary or crack (QG).

By manufacturing the input surface of the X-ray image tube using the method described above, a material with high light reflectivity can be added to the grain interface of each columnar crystal. It is possible to form an input surface that can be effectively filled and completely prevent lateral light diffusion within the phosphor film. And as a result, the resolution in the X8 image q5f, conl-las)
It is possible to further improve the overall image quality including

[Brief explanation of the drawing]

Figure 1 is a schematic diagram explaining the structure of the xi image tube;
The figure is a cross-sectional view of a portion of the manpower side, and FIG. 3 is an enlarged drawing showing a portion of the manpower side of a 2'Lk X-ray image tube manufactured by the method of the present invention. 12... Input surface 21... Substrate 22... Fluorescent material vacuum-deposited film 23... Fine powder material Re... Columnar crystal 25... Grain boundary or crack 26... Kouyuan Katanai Agent Patent Attorney Uke Kitamura'w'l'j",+'
j. −j′−・1−ξ Tuna ≦1 figure ``”2 figure year 3 figure 6

Claims (1)

[Claims] 1. A method for manufacturing an input surface of an X-ray image tube, which comprises forming a phosphor vacuum-deposited film on a substrate surface and forming a photoelectric film on the vacuum-deposited film, wherein the vacuum-deposited film is formed. A method for manufacturing an input surface of an X-ray image tube, characterized in that a substance having a high light reflectance or a high light absorption rate is filled in a powder state with a particle average diameter of 1 μm or less into the grain boundaries or cracks of each columnar crystal. 2. The method of manufacturing an input surface of an X-ray image tube according to claim 1, wherein the filling of the substance with high light reflectance or high light absorption rate is carried out by a vacuum deposition method.