Title :
Fabrication of coherent optical transversal filter consisting of MMI splitter/combiner and thermo-optic amplitude and phase controllers
Author :
Okamoto, K. ; Yamada, H. ; Goh, T.
Author_Institution :
NTT Photonics Labs., Ibaraki, Japan
fDate :
8/5/1999 12:00:00 AM
Abstract :
The fabrication of an integrated-optic coherent transversal filter which is capable of synthesising almost arbitrary filter characteristics is reported. The transversal filter consists of a multimode interference (MMI) splitter for 1×N signal splitting, delay arms with fixed path length difference, thermo-optic switches and phase shifters for arbitrarily weighting the signal and MMI N×1 combiner to combine N tapped signals. Sine-type and Gaussian-type spectral filter responses have been successfully realised showing good agreement with theoretical characteristics
Keywords :
integrated optics; interference filters; optical delay lines; optical phase shifters; optical waveguide filters; power combiners; Gaussian-type spectral filter response; MMI splitter/combiner; arbitrary filter characteristics; coherent optical transversal filter; delay arms; fixed path length difference; integrated optics; multimode interference; phase shifters; signal splitting; sine-type spectral filter response; tapped signals; thermo-optic amplitude controller; thermo-optic phase controller;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19990940
