将双群模型计算的宽束电子的能量沉积与Fermi Eyges理论的侧向解相结合来构造电子笔束模型 ,即混合笔束模型 .由于混合笔束模型的计算精度和效率较好 ,并且适用范围较大 ,因此 ,混合笔束模型展示了在放射治疗临床应用上的可能性 .在混合笔束模型的基础上 ,改进了混合笔束模型对电子侧向分布的参数计算 .计算结果表明 ,改进的混合笔束模型的精度符合临床应用的要求 ,同时 ,其计算速度非常快 .因而显示出较好的临床应用价值 The electronic pencil beam model, that is, the hybrid pencil beam model, is constructed by combining the energy deposition of wide-beam electrons calculated by the two-group model with the lateral solution of Fermi Eyges theory.As the hybrid pencil-beam model has better calculation accuracy and efficiency, Therefore, the hybrid pencil-beam model shows the possibility of clinical application of radiation therapy.On the basis of the hybrid pencil-beam model, the parameters of the hybrid pencil-beam model for the lateral distribution of electrons are improved.The calculation results show that, The accuracy of the improved hybrid pencil-beam model accords with the requirements of clinical application, and at the same time its calculation speed is very fast and thus shows a good clinical application value