An optical device with at least one junction formed by an intersection of at least two waveguides may be used to tap, and/or attenuate an optical signal. The waveguides may be formed from various materials such as polymers and other combinations of monomers. Internal reflection produced at each junction between the waveguides in response to heating from a thin film electrode will direct a portion of an optical signal from one of the waveguides to another waveguide. Internal reflection at each junction may be used to selectively tap and/or attenuate power level of an optical signal.