RI - Refractive Index (n) - DTX xFM Fiber Adapters

refractive index (n): Of a medium, the ratio of the velocity of propagation of an electromagnetic wave in vacuum to its velocity in the medium.
The index of refraction is the ratio of the speed of light in a vacuum to the speed of light in a fiber. The tester uses the index of refraction to determine fiber length. The unit of measure is n. The n values defined in the fiber types menu of the DTX CableAnalyzer are suitable for most applications. Minor differences between the tester's n and a fiber's actual n usually do not make enough difference in length to fail a fiber.
Increasing n decreases measured length. If you try to enter a value outside the valid range for n, the DTX CableAnalyzer shows N/A for the value. The valid range is 1.1 to 1.71 inclusive.