为了高效率地重建3维医学图像，并能充分显示内部隐含分界面及内部细节的详细信息，提出了一种能在普通硬件条件下实现的用于半透明体绘制的光学模型IVROM(improved volume rendering optical model)。该模型在光线吸收与发射模型的基础上，考虑了阴影、直接散射与间接散射等因素。此外，还详细介绍了结合该模型与Shear-Warp算法的半透明体绘制方法的实现。实验结果表明，采用该模型的半透明体绘制方法不仅效率高，而且显示效果好。

In order to efficiently reconstruct 3D medical image and clearly display the detailed information of inner structures and the inner hidden interfaces between different mediums, an improved volume rendering optical model(IVROM) for translucent volume rendering is proposed, which can be easily realized on a general PC. On the basis of classic absorption and emission model, the effects of volumetric shadows, direct and indirect scattering are also considered in the proposed model Moreover, the implementation of the translucent volume rendering method incorporating the IVROM model and Shear-Warp is described detail. Experiments demonstrate the good performance of the proposed method.