| 摘要 |
A filter includes a plurality of filter plates for adjusting X-ray energy spectrum, a plurality of rails for fixedly supporting the filter plates, a plurality of cams which are respectively provided with a groove curve on a surface thereof, a driving wheel for driving the cams, and a plurality of link levers, each link lever being connected to one of the filter plates at one end and being mounted to an axis at an opposite end such that the link lever is rotatable about the axis, and each link lever being provided with a pin which is in cooperation with the groove curve of the corresponding cam so that the link lever proceeds with a reciprocating movement according to rotation of the corresponding cam to move the filter connected to it into or out of the X-ray passing space. The plurality of cams are respectively located at different sides of the driving wheel to move the filter plates into the X-ray passing space from different directions. |
