| For several decades, light loss of optical fibers was a major drawback before revolutionizing fiber telecommunication. Waveguides have many more advantages to fabricate a variety of optical communication components than fibers. The sol gel process makes it possible to control the waveguide component (cladding and core) refractive index. Sol gel waveguides show superior low light loss to polymer waveguides. Low light loss (0.16 dB/cm) was achieved with an aged sol gel slab waveguide. The proper index difference of the cladding and core was able to launch light to the 4&inches; length single mode waveguide. Controlled process conditions were able to fabricate well defined, high quality, and reproducible waveguides. Multifactor lithographic process conditions were achieved to fabricate slab, single mode, and multimode waveguides. For the economical reason, a 365 nm light source would be a better choice to fabricate single and multimode waveguides and general photolithography process.; The light loss can be compensated by waveguide amplifiers. The waveguide amplifiers will become important telecommunication components introducing wavelength division multiplexed (WDM) or dense wavelength division multiplexed (DWDM) channels. Chemically modified erbium doped waveguide amplifiers overcome photoluminescence quenching by −OH group or water molecule and achieved communication wavelength amplification. |
