Interference spectroscope

A spectroscope that uses the interference of light. If the light from a light source is divided into many groups of parallel light by an appropriate method, and then collected and interfered with by a lens, the light will be strengthened in directions where the optical path difference between each group is an integer multiple of the wavelength, and weakened in other directions. With this method, the optical path difference between the interfering groups is large. In other words, the resolution is high because the order of the spectrum is high. Also, because there are a large number of interfering light waves, sharp bright lines can be obtained. Examples of this type include the Fabry-Perot interferometer and the Rummer-Goehrke interferometer. Interferometers have much higher resolution than prism spectroscopes, so they are used to study the fine structure of spectral lines.

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

光の干渉を利用した分光器．光源からの光を適当な方法によって多数の平行光の群に分け，これをレンズで集めて干渉させれば，各群間の光路差が波長の整数倍になる方向で光は強められ，そのほかの方向では弱められる．この方法によれば，干渉する群間の光路差が大きい．すなわち，スペクトルの次数が高いために，分解能が高くなる．また，干渉光波の数が多いために，鮮鋭な明線が得られる．ファブリ-ペロー干渉計やルンマー-ゲールケ干渉板などはこれに属する．干渉分光器はプリズム分光器に比べて分解能が非常に高いために，スペクトル線の微細構造を研究するのに用いられる．

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