X-ray diagnostic installation with subtraction stage

摘要

An x-ray diagnostic installation has a video display system connected to the output of an x-ray image intensifier, the video system including a subtraction stage with a weighting circuit connected to an image memory for suppressing image noise the subtraction stage also having a difference forming element for subtracting image information arising at different times. The output of the difference forming stage is supplied to a threshold circuit and the output of the threshold circuit is read into another image memory picture element-by-picture element. This memory is connected to the weighting circuit such that the output thereof controls the parameters of the weighting circuit picture element-by-picture element. A filter circuit may be interconnected between the output of this memory and the weighting circuit.