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Fabrication of optical ion-exchanged glass waveguides by using thin-film silver ion sources is studied with reference to the use of salt-melt sources. Since the amount of silver in a thin-film source is limited, the process is source controlled, and it is shown that temperature and time as controlling parameters in the process can be replaced by source dimensions. Channel waveguide depth profiles are calculated. When contact film over patterned silver-film-stripe sources is used, silver can be used totally, which results in good uniformity in waveguide depth.

Circular optical waveguides have been fabricated from vacuum-deposited Ag layers by ion migration technique into soda-lime substrate glass. In this method two different guide patterns, one of which is the mirror image of the other, are made. Later the guide patterns are placed on top of each other and circular guides are thus obtained. The ends of the guides are studied by optical microscope and the near-field scanning method. The optical loss spectrum is measured from 450 to 1600 nm.

Wavelength multiplexers and demultiplexers using a chirped grating and an ion-exchanged multimode waveguide are presented. The waveguide is prepared by the electric-field-assisted ion-exchange technique, and the chirped grating is fabricated by the computer-controlled electron-beam writing technique. The device requires no collimating and focusing components and has the advantages of (1) high resolution, (2) large channel number, (3) small cross talk, (4) low insertion loss, (5) low loss coupling to multimode fiber, (6) compact and stable rugged structure, and (7) possibility of economical mass production. The design considerations and the fabrication process are described, and the demultiplexing characteristics of the fabricated device are discussed.

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