Fig. 6From: Collimator scatter factor: Monte Carlo and in-air measurements approachesMeasured collimator scatter factors. The Mini-Phantom has 4 cm diameter, and measurements were acquired at 10 cm depth of PMMA. Build-up caps were of PMMA and brass material, and had water equivalent thicknesses in mm according to the legend, in perpendicular or parallel setting relative to the beam axisBack to article page