H. Ghafourishiraz et al., ANALYSIS OF A LAMBDA 4-PHASE-SHIFTED DOUBLE PHASE-SHIFT-CONTROLLED DISTRIBUTED-FEEDBACK WAVELENGTH TUNABLE OPTICAL FILTER/, IEEE journal of quantum electronics, 33(4), 1997, pp. 556-561
We have proposed a new lambda/4-phase-shifted double phase-shift-contr
olled distributed feedback wavelength tunable optical filter structure
. Theoretical analysis based on the transfer matrix method reveals tha
t this filter can achieved a wavelength tuning range of 28.3 and 34.3
Angstrom for the grating coupling coefficients of 6 and 10 mm, respect
ively, The filter has almost constant peak transmissivity (gain) of mo
re than 30 db within its tuning range, and its side-mode suppression r
atio (SMSR) ranges from 15 to 34.7 dB.