Fig. 1. Schematic diagram of the SPR sensor based on D-shaped high birefringence photonic crystal fiber

Fig. 2. The influence of polishing height and polishing angle on the birefringence of photonic crystal fiber

Fig. 3. Effective refractive index and mode field distribution of the mode

Fig. 4. Refractive index sensing theory analysis

Fig. 5. Effect of polishing angle on the optical transmission characteristics of D-type highly birefringent PCF

Fig. 6. Photonic crystal fiber side-polised system

Fig. 7. Cross-section of D-shaped high birefringence photonic crystal fiber

Fig. 8. Schematic diagram of real-time online measurement system

Fig. 9. Experimental analysis of refractive index sensing

Fig. 10. Glucose concentration detection analysis