X-RAY EXAMINATION APPARATUS INCLUDING AN X-RAY FILTER
摘要
An X-ray examination apparatus includes an X-ray source (1) for emitting X-rays. An object to be radiologically examined is arranged in an examination space. An X-ray detector (2) derives an image signal, for example an electronic video signal, from an X-ray image of the object. An X-ray filter locally attenuates the X-rays partly. The X-ray filter is arranged between the X-ray source and the X-ray detector and the X-ray filter is provided with filter elements whose X-ray absorptivity can be adjusted on the basis of an amount of X-ray absorbing liquid present within the individual filter elements. The X-ray examination apparatus includes an X-ray collimator for locally intercepting the X-rays. The X-ray collimator is arranged between the X-ray source and the examination space and is provided with collimator elements which can be switched between an X-ray transmitting state and an X-ray intercepting state. Individual collimator elements are filled with an X-ray intercepting liquid in the X-ray intercepting state. The amount of X-ray absorbing liquid present in the filter elements is controlled by application of an electric voltage to the relevant filter elements. The collimator elements are switched between the X-ray intercepting state and the X-ray transmitting state by means of an electric voltage which is applied to the relevant collimator elements.