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3.15 CR Reader Scanner Performance
Chapter 3
3.15.4 Procedure
z
Geometric Distortion
1
Set the Al plate under the X-ray tube.
2
Place a cassette into the cassette holder.
3
Place the steel scale on the breast support table lengthwise with the table.
4
Place one marker at zero mark and the other one at 150 mm mark of the steel scale.
5
Expose the cassette with 28 kVp 100 mAs (Mo/Mo).
6
Process the cassette under the Geometric Distortion exam tag.
7
Measure the distance between the markers. Compare it with the true value and calculate the
error.