Postfabrication exposure of gap-type bandpass filters in broadly chirped fiber gratings.
High efficiency in-fiber bandpass filters with arbitrary passband/stop-band combinations have been produced successfully with an UV postfabrication exposure technique in broadly chirped fiber gratings. By further concatenating such a bandpass filter with two additional chirped gratings we achieved a finesse as high as 220 for a 36-nm stop band. This new approach exhibits great advantages in controlling precisely the profiles of bandpass filters in terms of stop-band width, transmission wavelength and linewidth, and spacing of passbands.
Zhang
L
L
Sugden
K
K
Williams
J A
JA
Bennion
I
I
Reid
D C
DC
Ragdale
C M
CM