Practical quantitative measurement of graticule misalignment relative to collimator axis of rotation

摘要

We design a practical procedure for measuring translational and rotational misalignment of graticule with collimator axis of rotation and collimator jaws, respectively. The procedure's quantitative results are accurate to less than 0.2 mm (at isocenter) and do not assume alignment of radiation focal spot with collimator axis of rotation. When provided with these quantitative results, the manufacturer can custom‐adjust graticules to the purchaser's collimator head.PACS number: 87.56.Fc