Development of ultralow-loss glasses by controlling density fluctuations

通过控制密度波动开发超低损耗玻璃

• 批准号: 09355021
• 负责人: IKUSHIMA Akira J.
• 金额: $ 18.24万
• 依托单位: Toyota Technological Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09355021/
• 关键词: optical fiber; silica glass; glass transition; structural relaxation; ガラスファイバ; optical fiber; silica glass; glass transition; structural relaxation; ガラスファイバ

Since light scattering loss in silica fiber is dominantly caused by "frozen-in" density fluctuations at the glass transition temperature, investigations of structural relaxation around the glass transition temperature are necessary for developing ultralow-loss silica glasses. In this project we tried to measure various properties of silica glasses over a wide-temperature range including the glass transition temperature, and have elucidated structural relaxation processes and their impurity effects as follows :(1)OH or Cl enhances the alpha -relaxation governed by viscous flow, and also generates a sub-relaxational process.(2)he sub-relaxational process is local structural change caused by impurity diffusion.From these results, we have established controlling the structural relaxation by impurity doping, which is a basic technology to develop ultralow-loss glasses. For example, the light scattering loss was reduced by 13% by the addition of only 10 wt.ppm Na_2O to silica glass. This method is also useful for developing silica glasses with high performances such as high UV-proof and high heat-proof properties.

由于二氧化硅纤维中的光散射损失主要是由于玻璃过渡温度下的“冷冻 - in”密度波动引起的，因此对玻璃过渡温度周围的结构弛豫的研究对于开发超低硅胶眼镜是必需的。在这个项目中，我们试图在广泛的范围内测量二氧化硅玻璃的各种特性，包括玻璃过渡温度，并阐明了结构放松过程及其杂质效应，如下所示：（1）OH或CL增强了由粘性流动控制的alpha-递归，并由粘性流动，并引起了这些局部构成过程。我们已经建立了通过杂质掺杂来控制结构放松的，这是一种开发超损坏眼镜的基本技术。例如，通过仅将10 wt.ppm na_2o添加到硅胶玻璃中，光散射损失减少了13％。该方法也可用于开发具有较高性能的二氧化硅眼镜，例如防紫外线且防暖性能高。