Figure 19. Mp1 Ion Optics - Thermo Scientific LTQ Series Hardware Manual

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Functional Description
Mass Spectrometer
MP1 Ion Optics
22 LTQ Series Hardware Manual
The lens L1 is a metal plate with a circular hole in the center through which the ion beam
passes. An electrical potential applied to the lens accelerates (or decelerates) ions as they
approach the lens. This electrical potential focuses the ion beam as it passes through the lens.
Lens L1 also acts as a vacuum baffle between the MP0 ion optics chamber and the mass
analyzer chamber.
The MP1 ion optics transmit ions from the MP0 ion guide to the mass analyzer. The MP1
ion optics include MP1 and the split gate lens
Multipole MP1 is an array of circular rods that act as an ion transmission device similar to
multipole MP0. An rf voltage applied to the rods creates an electric field that guides the ions
along the axis of the multipole. The MP1 offset voltage increases the translational kinetic
energy of ions that emerge from MP0.
A split gate lens starts and stops the injection of ions into the mass analyzer by deflecting the
beam at high speeds at the appropriate times. For positive beams, the split gate lens opens at
–90 V and closes at 50 V.

Figure 19. MP1 ion optics

LXQ and LTQ XL
(Figure 19).
Split gate lens
Velos Pro
Thermo Scientific