Boge R J, Tolbert D D, Edland R W
Radiology. 1975 May;115(2):475-7. doi: 10.1148/115.2.475.
An accessory beam flattening filter (brass disk with critical angles) attaches to the shadow tray of the clinac-4 linear accelerator, intercepts the x-ray beam, and eliminates higher dose areas at the edges of large fields near the skin surface. This improves the x-ray beam dose distribution within the patient and results in a reduction of dose to normal tissues near the surface.
一个辅助束流平坦化滤波器（带有临界角的黄铜盘）附着在 Clinac - 4 直线加速器的阴影托盘上，拦截 X 射线束，并消除皮肤表面附近大射野边缘的高剂量区域。这改善了患者体内的 X 射线束剂量分布，并导致体表附近正常组织的剂量降低。
