Interference Refractometer

An interferometer used to measure the refractive index of light. When light from a single light source is split into two optical paths and then recollected, light and dark interference fringes due to light interference can be seen. When a medium with refractive index n and length l is inserted into one of the optical paths, the optical path difference changes by ( n - 1) l , and the refractive index n is measured from the resulting shift in the position of the interference fringes.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

光の屈折率測定の目的に用いる干渉計．一つの光源からの光を二つの光路に分け，これをふたたび集めると光の干渉による明暗の干渉じまが見られる．光路の一方に屈折率n，長さlの媒質を挿入すると光路差は(n － 1)lだけ変化し，これによって生じる干渉じまの位置の移動から，屈折率nを測定する．

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