摘要 |
A fiber optic switch based on a Mach-Zender type interferometer comprises first and second input optical fibers, first and second intermediate optical fiber segments, and first and second output optical fibers. The switch selectively couples the first and second input fibers either to the first and second output fibers, respectively, or to the second and first output fibers, respectively. To operate the switch, an optical path length of the first intermediate fiber segment is changed, and an optical path length of the second intermediate fiber segment is altered by an equal and opposite amount. Heat is therefore deposited equally in each of the intermediate fiber segments. The intermediate fiber segments lie substantially in a plane, thereby ensuring that the polarization of light traveling through the first intermediate fiber segment does not rotate significantly relative to the polarization of light traveling through the second intermediate fiber segment.
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