bragg gratings

Hi all,

I was looking for some online tutorial which gives basic information
(formulas) about the Bragg grating parameters, such as the passband (or

stopband) width and profile in terms of the index and period etc., and
the spectrum of the grating with defects etc. Please tell me if know of

some such tutorial.
In addition, I would like to know the name of some book which contains
this type of stuff.


Any help would be appreciated.
Thanks

.