The main estimation is the rugosity and the linear rugosity of the fracture surface. A set of theoretical models has been built.
评价的主要内容集中在裂隙面粗糙度和线粗糙度方面，并建立了一系列的理论模型。
Results Typical acoustic properties of complete PVD presented clearly the vitreous posterior boundary membrane echo, rugosity and slender wave form, which didn't connect with the eyeball wall;
