Figure 2
Custom built phantoms for measuring CT dose indices and their `bow tie' filters, with dimensions (from left to right) of width × depth of 260 mm × 170 mm (filter void diameter D = 160 mm), 200 mm × 110 mm (D = 100 mm), 150 mm × 60 mm (D = 50 mm) and 135 mm × 45 mm (D = 35 mm). |