A new concept of electro-optically reconfigurable waveguide superimposed gr
atings with their widely controllable transmission characteristics are pres
ent. It is based on two types of superimposed refractive index gratings, el
ectronically induced in an electro-optically active core. These gratings ca
n be independently switched ON and OFF or both simultaneously activated wit
h the controllable weighting factor. In this case its transmission characte
ristics represent double-dip rejection band spectrum with independent contr
ol of the dip positions and bandwidth. This simple concept opens opportunit
ies for developing a number of tunable devices for integrated optics by use
of the proposed design as a building block. (C) 2001 Optical Society of Am
erica.