Fabrication And Characteristics Of Optical Fiber Sensor Based On Twist Method

With the deepening of the research on optical fiber sensing,various new types of fiber optic sensors are endless.Therefore,the production method of innovation is very necessary.In this paper,the development of fiber grating is briefly introduced,and then based on a new spiral fixture,design and manufacture of three new fiber optic sensors,a high frequency CO₂ laser rotary writing long period fiber grating,a Mach-Zehnder interferometer based on the twist structure and a twist fiber grating based on the twist structure respectively.In this paper,the temperature characteristics,twist characteristics or strain characteristics of these three kinds of fiber optic sensors are measured and analyzed respectively.The high frequency CO₂ laser rotary writing long period fiber grating can identify the twist direction.The maximum temperature sensitivity is76 pm/oC and the maximum twist sensitivity is 0.074nm/?rad/m?.The Mach-Zehnder interferometer based on the helical structure can be used for simultaneous temperature-strain measurement,and verify the effect of the prepared helical structure on optical waveguide transmission.The twist grating structure based on twist structure is novel.The twist sensitivity reaches 0.11nm/?rad/m?,and the twist direction can be recognized.