Abstract:

Fiber Bragg grating has been widely used in engineering fields.Because of the complex demodulation system，high cost，and the need to use fiber Bragg grating wavelength interrogating system，fiber Bragg grating is difficult to demonstrate in the experiment teaching of undergraduate courses.In this paper，an intensity demodulation method based on a narrow line-width DFB laser is proposed，which can greatly simplify the demodulation system of fiber Bragg grating sensor and fully meet high resolution and real-time detection system requirements.Properly arranged temperature sensing experiments could intuitively show the linear sensing performance of fiber gratings.The engineering fiber Bragg grating sensing technology could easily demonstrate in undergraduate education. Students should better understand and master the optical fiber sensing technology in engineering application through the experiment.The intensity demodulation system is of great value to promotion and application.

Key words: temperature sensing, fiber Bragg grating, the intensity demodulation