Fiber optic devices including volume Bragg grating (VBG) elements are
disclosed. A fiber optic device may include one or more optical inputs,
one or more VBG elements, and one or more optical receivers. Methods for
manufacturing VBG elements and for controlling filter response are also
disclosed. A VBG chip, and fiber optic devices using such a chip, are
also provided. A VBG chip includes a monolithic glass structure onto
which a plurality of VBGs have been recorded.