Sensing and Demodulation of Special Long-Period Fiber Gratings Induced by Scanning CO_𝟐 Laser Pulses

Figure 4

(a) Photograph, obtained from a charge-coupled device camera, of the CO₂-laser-carved LPFG with a grating pitch of 400 μm. (b) Transmission spectrum evolution of the LPFG with a grating pitch of 400 μm while the grating periods vary from 20 to 80 [3].

(a)

(b)