Patent attributes
An ion transport optical system is disposed between a collision cell and an orthogonal acceleration unit. When releasing ions that are held in the collision cell, an accelerating electric field in which a large potential difference exists is created between an exit-side end of an ion guide and a first stage of the ion transport optical system, and a decelerating electric field in which a relatively small potential difference exists is created between a final stage of the ion transport optical system and an entrance end of the orthogonal acceleration unit. In the accelerating electric field, the velocity of ions is increased overall by imparting a large amount of energy to the ions, and spreading of ions in the ion travel direction that is caused by differences between the mass-to-charge ratios of the ions is reduced.
