Dr Hess envisages a ray of light travelling down an optical fibre made from two materials: a core with a negative refractive index and an outer sheath with a positive one.

赫斯博士构想出一个画面，即一道光正穿越于一个由两种材料制作的光导纤维，一种是具有正折射指数的纤维核，另一种则是具有正折射指数的外围。

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Is mainly used as additive for special optical glass and fibre glass slice with high index of refraction for electronic microscope and energy-saving light.

主要用作特种光学玻璃和光学纤维，高折射电镜片和节能电光源的添加剂。

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In this article, the principle and application of a new kind of instrument used to test the tensile stiffness index and fibre orientation distribution on a paper sheet were introduced.

本文介绍了一种用于实验室检测纸页纤维定向结构的新型仪器，分析了该仪器的基本原理、主要用途及对纸页抗张挺度检测的意义。

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