A refractive defect of a lens or other optical system that prevents light rays from converging at a single point resulting in a blurred or imperfect image.
散光有折射缺陷的透镜或其它光学系统，阻碍光线汇聚于一个焦点，形成一个模糊或不完全的图象。
2
The mode properties of symmetric and non-symmetric one-dimensional photonic crystals with a sandwich layer defect were investigated by using the optical transmission matrix method.
利用光学传输矩阵方法研究对称和非对称一维缺陷光子晶体的缺陷模式特性。
3
The influence of thickness error of each layer to optical character was also discussed, and the result shows that the most sensitive layer is defect-layer.