MULTIPLE CIRCULATION TIME-OF-FLIGHT MASS SPECTROMETER

• Main Authors: FURUHASHI OSAMU, KINUKAWA TORU
• Format: Patent
• Language: English; Japanese
• Published: 16.10.2014
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To generate a mass spectrum of wide mass range and high precision that solves the problem of ion overtaking on a circulation orbit with less measurement frequencies as much as possible, relating to a multiple circulation time-of-flight mass spectrometer.SOLUTION: Using a detector 8 in which micro detectors are arranged in two-dimension, deflection electrodes 71-74 are provided on an injection orbit through which an ion departed from a circulation orbit advances toward a detector 8. The deflection electrodes 71-74 are applied with a voltage which changes as time passes from the time point when a gate electrode is released to temporarily change an intensity of electric field. In a case two kinds of ions having different m/z reach the detector 8 at the same time because of circulation delay on the circulation orbit, the intensity of electric field that is received is different since the time, at which the two kinds of ions pass a deflection electric field, is different. Consequently the position to which ion reaches on a detection surface varies, and based on the displacement amount of reached position, a deflection electric field passing time for each ion is obtained. Thus, a flight speed of each ion is obtained, to allow estimation of approximate circulation frequency, and m/z is acquired from a flight time. 【課題】多重周回飛行時間型質量分析装置において、極力少ない測定回数で周回軌道上でのイオンの追越しの問題を解消した広質量範囲で高精度のマススペクトルを作成する。【解決手段】微小検出器が２次元的に配置された検出器８を用い、周回軌道から離脱したイオンが検出器８へ向かう射出軌道上に偏向電極７１〜７４を設ける。偏向電極７１〜７４にはゲート電極が開放される時点から時間的に変化する電圧を印加し、時間的に電場の強さを変化させる。周回軌道上での周回遅れのためにm/zが異なる２種のイオンが同時に検出器８に到達した場合、該２種のイオンが偏向電場を通過する時刻は異なるから受ける電場の強さは相違する。そのため、検出面上でのイオン到達位置には相違が生じ、到達位置の変位量から各イオンの偏向電場通過時刻が求まる。これより、各イオンの飛行速度が求まり、おおよその周回数が推定できるため、飛行時間からm/zを求めることができる。【選択図】図２