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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The material choice is simple: the shoe is a laminate with Carbon fibre for the core which gives the shoe its spring and strength, leather on the foot side and rubber on the walking wearing side.

这种材料的选择很简单：鞋材以一层碳纤维为主，碳纤维能提供鞋子必须的支撑强度，也很有弹性，接触脚的一面贴着皮革，鞋底的一面贴着橡胶。

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The properties of the new optical fibre made of BP-81-16 cladding glass and F626/356 core glass are satisfactory.

其中BP-81-16包层玻璃已投入生产，它与F626/356芯玻璃组合拉制的光导纤维性能良好。

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This generates the coherent light of a laser beam in the core of a long, thin optical fibre.

ECONOMIST: Solar power from space

One example the company has developed is a crystal fibre that squeezes light into such a narrow core that the intensity of the light modifies the optical properties of the glass itself.

ECONOMIST: A new approach to making optical fibres

In the same way, the pattern of holes in a crystal fibre can create the equivalent for light of a graphite core and a diamond cladding.

ECONOMIST: A new approach to making optical fibres