They have a single refractive index and so do not scatter light, so making the wings transparent.

它们有单一的发射率以至于不会散光，使得翅膀是透明的。

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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。

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Then, the dispersion of the multi-clad fiber is obtained by solving the propagation constant and the equivalent refractive index of single-clad fiber which is equal to multi-clad fiber.

通过将多包层光纤等效为阶跃光纤，求等效阶跃光纤的传播常数与等效折射率，求得多包层光纤的色散。

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