supported by the National Natural Science Foundation of China (No.60808004);the Fund of New Century Excellent Talents in University (No.NCET-07-0611);Tianjin Natural Science Foundation (No.08JCYBJC14500)
Multi-π-phase-shifted fiber Bragg gratings and π-phase-shifted sampled fiber Bragg gratings(SFBGs) with dual wavelength filtering properties are compared.Results show that both of these gratings have the dual wavele...