geometrical focus meaning in English
几何焦点
Examples
- According to geometrical focusing theory , the gamma knife can focus in spirals 30 beams of co - 60 gamma rays through a collimator to form a high - quality high - dose radiation field . the size of radiation filed can be varied and shaped according to tumor size for 3d radiotherapy . therefore , it can effectively increase radiation dose to tumor tissues and decease radiation dose to normal tissues
根据几何聚焦原理，将30束钴60伽玛射线通过准直后经一个固定的轴线旋转聚焦，形成品质优良的高剂量区分布，经治疗计划系统的优化，可使高剂量区的剂量分布，在三维方向上和肿瘤的形状一致，从而实现三维适形放射治疗。