Half-field Geometry In Mammography

Perpendicular Mammogram

Therefore, in order to compare measured and nominal focal-spot sizes, the measurement made at the chest wall needs to be corrected to estimate its size at the reference axis. The reference axis usually bisects the angle formed by the x-ray tube target and the ray perpendicular to the image receptor at the chest-wall edge of the image receptor . Thus, for an x-ray tube with an effective target angle of 22 degrees target angle of 16 degrees plus a tube tilt of six...