| 摘要 |
The objective of the present invention is to provide a mass spectrometer with which it is possible to improve the ionic permeability ratio of the entrance to an ion transport part (3) or the entrance to a mass spectrometry part, and to obtain a high-sensitivity mass spectrum. To resolve the above problems, the present invention is provided with electrodes in order to reduce the electric-field distortion that is caused by ion loss and occurs at the entrance to the ion transport part (3) or the entrance to a mass spectrometry part (4), the electrodes being arranged so that the radius (ri) of a circle inscribed within the electrodes (14a, b) of the ion transport part (3) is larger than the radius (rq) of a circle inscribed within the electrodes (13a, b) of the mass spectrometry part (4), and the entrance to the electrodes of the mass spectrometry part (4) having a tapered configuration. This means reduces the sharply fluctuating (peak-shaped) distribution of electric potential generated near the entrance to the ion transport part (3) and the entrance to the mass spectrometry part (4); i.e., reduces the electric-field distortion occurring at the end parts of the electrodes. Therefore, the ionic permeability ratio near the entrance to the ion transport part (3) and near the entrance to the mass spectrometry part (4) is greatly improved, and high-sensitivity mass spectrometry is possible. |
