应用标记控制分水岭分割算法研究激光诱导玻璃体损伤形貌

为了定量客观地分析玻璃的体损伤形貌,运用基于改进的分水岭分割算法对其微观图像进行了分析处理,得到了损伤的范围和分类,同时结合激光等离子体冲击波与玻璃的相互作用机理对各个处理后图像的物理含义及其应用进行了分析。研究结果表明,图像的梯度图可以反映图像中裂纹的形状及其分布;滤波后的图像灰度可以反映损伤程度;目标区域的标记图可以标记损伤的区域;最终分割图像可以全面反映以上所有信息。根据图像分析结果可以定量计算出各个区域所占总面积的比例,即等离子通道区、熔蚀区、折射率变化区各约占总面积的15%,55%和30%。这说明激光能量先沉积到很小范围的等离子通道区,高温高压等离子体向外扩展形成大范围熔蚀区,随着距离的增大,冲击波压强迅速减小,形成折射率变化区。

Morphological analysis of laser induced glass bulk damage by marker controlling watershed algorithm

The laser induced glass bulk damage morphology has been analyzed quantitatively,and the size and classification of the damage are obtained by using the image processing technology based on the improved watershed segmentation algorithm. The physical meaning and application of each processed image are analyzed in detail based on the interaction mechanism between the laser-induced plasma shock waves and the glass. The results show that the gradient picture can reflect the shape and distribution of a crack, the shade of the image gray aftering filter can reflect the degree of the damage, the marker picture of object region can reflect the region of the damage,and the final segmentation result owns all the characteristics above and can fully reflect all information mentioned above. Furthermore,each area is analyzed of the light of the final segmentation images. The analysis results show that the ratios of the filamentary of plasma channel, the fusion range and the region of varying refractive index to the entire analyzed area are about 15％,55％ and 30％, respectively.The result implies that laser energy is deposited into the small range of filamentary of plasma channel firstly; Following that, the plasma expands outward because of the high temperature and extreme pressure to form a large fusion range; With the increase of the distance from the centerline, the pressure of the laser plasma shock wave will reduce rapidly and the region of varying refractive index is formed.