| 摘要 |
An analytical apparatus (1) for mass spectrometry comprises an electron impact ioniser including an electron emitter (22) and an ionisation target zone (18). The target zone (18) is arranged to be populated with matter to be ionised for analysis. An electron extracting element (36) is aligned with an electron pathway (34) defined between the electron emitter (22) and the ionisation target zone (18). The electron extracting element (36) is configured to accelerate electrons away from the emitter (22) along the electron pathway (34) between the emitter (22) and the extracting element (36) and to decelerate the electrons along the electron pathway (34) between the extracting element (36) and the ionisation target zone (18) to enable soft ionisation while avoiding the effects of coulombic repulsion at the electron source (22). |
