Abstract Reflectron time-of-flight mass spectrometer (RTOF-MS) is a powerful tool to achieve high resolution in mass analysis of various ions. As it is often supposed that analyte ions are generated in a small volume in the ion-extraction region, its performance is not optimized for ions spread over a large volume. Not only the mass resolution is degraded due to incomplete space and energy focusing, but also the ion beam is subject to significant divergence of ion trajectories after it is reflected from an ion reflector. Here we present a novel design of RTOF-MS equipped with an additional electrostatic lens in front of a conventional grid-less ion reflector for improving convergence of an ion beam. The performance is examined by mass analysis of Ag3+ ions extracted from a volume of 6.3 cm3, i.e., a cylinder with 20-mm length and 20-mm diameter. The improved convergence of an ion beam is demonstrated by a two-dimensional image of ions on the ion detector. Mass resolution is evaluated as well.

中文翻译：

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改进反射式飞行时间质谱仪以实现更好的离子束会聚

摘要 反射式飞行时间质谱仪（RTOF-MS）是实现各种离子质量分析高分辨率的有力工具。由于通常假设分析物离子是在离子提取区域中以小体积生成的，因此其性能并未针对分布在大体积中的离子进行优化。不仅质量分辨率因空间和能量聚焦不完整而降低，而且离子束在从离子反射器反射后会发生明显的离子轨迹发散。在这里，我们展示了一种新颖的 RTOF-MS 设计，在传统的无网格离子反射器前面配备了一个额外的静电透镜，用于改善离子束的会聚。通过对从 6.3 cm3 体积（即长度为 20 mm、直径为 20 mm 的圆柱体）中提取的 Ag3+ 离子进行质量分析来检查性能。离子束的改进会聚由离子检测器上的离子二维图像证明。质量分辨率也被评估。