%0 Journal Article
%T A high sensitivity fiber-optic torsion sensor based on a novel ultra long-period fiber grating<br>基于超长周期光纤光栅的高灵敏度扭曲传感器
%A Zhu Tao
%A Rao Yun-Jiang
%A Mo Qiu-Ju
%A <br>朱涛
%A 饶云江
%A 莫秋菊
%J 物理学报
%D 2006
%I 
%X A high sensitivity fiber-optic torsion sensor is described,which measures twist rate and determines twist direction simultaneously by using a novel ultra long-period fiber grating (ULPFG) with periods of up to several millimeters fabricated by high frequency CO2 laser pulses. The torsion characteristics of a ULPFG are analyzed based on the coupling theory and birefringence phenomena. The experimental results show that a higher torsion sensitivity of 0.2244nm/(rad/m) for high order resonant modes was obtained, which is four times higher than that of the long-period fiber grating written by high frequency CO2 laser pulses. Finally, an intensity-type demodulation approach for the realization of real-time torsion measurement is proposed and demonstrated based on the edge filtering effect of the ULPFG.
%K optical fiber sensors
%K fiber gratings
%K CO2 lasers
%K torsion measurement
%K birefringence<br>光纤传感
%K 光纤光栅
%K CO2激光
%K 扭曲测量
%K 双折射
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=29DF2CB55EF687E7EFA80DFD4B978260&aid=B4D23C1F95E6AFB5&yid=37904DC365DD7266&vid=E514EE58E0E50ECF&iid=CA4FD0336C81A37A&sid=D537C66B6404FE57&eid=82722E2B785EBF0D&journal_id=1000-3290&journal_name=物理学报&referenced_num=0&reference_num=11