Unattenuated global modes in a planar dielectric waveguide with a flare in the direction of propagation

✍ Scribed by D. B. Singh; P. Khastgir; U. K. Singh; O. N. Singh

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 114 KB
• Volume: 19
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/(sici)1098-2760(199809)19:1<77::aid-mop21>3.0.co;2-#

✦ Synopsis

when the coupler returned to 20ЊC, showing that the effect is reversible with temperature.

In summary, the proposed process permits the fabrication of couplers with polarization extinction similar to the fiber's. Moreover, this kind of device presents very low loss, and exhibits good mechanical and thermal stability since the fibers and the quartz block are fixed with resin.

IV. CONCLUSIONS

A fiber orientation system which permits fast and simple fabrication of polarization-preserving couplers using a spot reflection alignment technique is presented. The obtained Ž . devices operating at the 850 nm window show good mechan-Ž ical stability, a steady coupling ratio of 0.16%rЊC 20᎐50ЊC . range , and a polarization extinction ratio higher than 27 dB, with an insertion loss lower than 0.2 dB. It is important to observe that the improvement of this device is dependent on the decrease in the unilateral rotation that causes fiber torsions. Devices using a 1.3 or 1.55 m monomode fiber would be easier to manufacture since those fibers have larger core diameters.