Fig. 1. Schematic diagram of CDC-PSG

Fig. 2. Variation of refraction index of Moire grating

Fig. 3. Segmented diagram of CDC-PSG. (a) Schematic diagram of segmentation within single cycle; (b) schematic diagram of segmentation of entire grating after simplification

Fig. 4. Output spectra of Through and Drop ports of CDC-PSG

Fig. 5. Design parameters and schematic diagram of CDC-PSG after apodization on facets of gratings

Fig. 6. Output spectra of CDC-PSG after apodization on facets of gratings

Fig. 7. Schematic diagram of CDC-PSG after apodization on waveguides of gratings

Fig. 8. Output spectra of CDC-PSG after apodization on facets and waveguides of gratings

Fig. 9. Structural diagram of CDC-PSG with semi-concave and semi-convex structure

Fig. 10. Output spectra of CDC-PSG with semi-concave and semi-convex structure