X-RAY EXAMINATION APPARATUS INCLUDING AN X-RAY FILTER

摘要

An X-ray examination apparatus of this invention comprises an X-ray source, an X-ray detector and an X-ray filter which is located between the X-ray source and the X-ray detector. The X-ray filter includes filter elements, notably capillary tubes, and the X-ray absorption of separate filter elements can be controlled by controlling a quantity of X-ray absorbing liquid in the respective filter elements. The quantity of X-ray absorbing liquid in the individual filter elements is controlled by way of electric voltages applied to the individual filter elements.The filter elements are formed as spaces between deformed foils which are arranged in a stack which is expanded in the direction transversely of the foils. Adjacent foils are locally attached to one another along seams. The stack is arranged between rigid plates and buffer elements are provided between the rigid plates and the stack. The buffer elements are contractable in the direction transversely to the direction of expansion of the stack. The shape of the cross-section of the capillary tubes is dependent on the ratio of the width of the seams to the spacing of the seams.