X1-044 (2007/04/19)

The Sagnac effect

Consider a light source and a detector in a closed optical fiber. The light from the source arrives at the detector through two paths and makes an interference pattern. If the fiber rotates, the phase difference of lights arriving the detector through the two paths changes and the interference pattern is translated. The change of the phase difference is claculated for an arbitrary shape of the optical fiber.

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