Manufacturing method of scattered radiation removing grid

A method of manufacturing a scattered X-ray eliminating grid, comprising the steps of:

• disposing guide slit plates such that they are fixed relative to one another, namely,
• parallel to and spaced apart from one another by a prescribed distance;
• forming numerous guide slits in each guide slit plate;
• fitting numerous metal foils, which serve as an X-ray absorbing substance provided between the guide slit plates, in the numerous guide slits such that they are parallel to primary X-rays;
• inserting both ends of the metal foils into opposing guide slits of each of the guide slit plates and, in that state, holding the metal foils on the outer sides of the slits in the state wherein an urging means applies tension to one end or both ends of the metal foils;
• bonding thin plates, which are made of a light element and serve as grid covers, to an X-ray incident side and an X-ray emergent side of the metal foils such that the thin plates cover the metal foils;
• removing the urging means and a fixing means of the metal foils;
• cutting off both ends of each of the metal foils at inner sides of the guide slit plates;
• and
• removing the metal foils from the guide slit plates on both sides;
• wherein,
• to enable the urging means to exert tension evenly over all of the metal foils, a rod, which is sheathed in an elastic body, is inserted into holes, which are formed in the metal foils on the tip sides of the metal foils beyond the inserted portions, in the state wherein vicinities of both ends of the metal foils are inserted into the guide slits, and thereby the metal foils are held and pulled;
• and
• a structure is adopted that ensures that the cross sectional shape of the elastic body sheathing the rod has a sufficient wall thickness in a direction in which the elastic body is compressed when tension is generated, which eliminates any difference in the tension even if a spring constant k that is determined during compression is small and the amounts of compression are different.