In the paper, a wide range displacement sensor based on the variable line-spacing (VLS) grating was proposed and its displacement characteristics at different temperature environments were measured. The VLS grating was inscribed by electron beam lithography method, and the sensor mechanical structure was designed and fabricated. A broadband light was irradiated to the VLS grating though a twin-core Y-type fibre, and an aluminizing reflector mirror was used to adjust light spot positions to change the displacement. In the experiment, the temperature stabilities of sensor were tested when the temperature rose from −20°C to 60°C, and the maximum drift of diffraction peak was less than 1.01 nm. In 30 mm length displacements, the diffraction wavelength was shifted simultaneously, the sensitivity was 15.941 and 15.917 nm/mm at 20°C and 50°C respectively, and the linearity was 0.994 both at 20°C and 50°C.

中文翻译：

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基于变线距光栅和Y型双芯光纤的大范围位移传感器

本文提出了一种基于可变线距(VLS)光栅的宽范围位移传感器，并测量了其在不同温度环境下的位移特性。采用电子束光刻法刻写了VLS光栅，设计并制作了传感器机械结构。宽带光通过双芯 Y 型光纤照射到 VLS 光栅，并使用镀铝反射镜调整光斑位置以改变位移。实验中，测试了传感器温度从-20℃升至60℃时的温度稳定性，衍射峰的最大漂移小于1.01 nm。在 30 mm 长度位移中，衍射波长同时偏移，在 20°C 和 50°C 下灵敏度分别为 15.941 和 15.917 nm/mm，