Patent ID: 9576782
Date: 2017-02-21
CPC Classifications: H01J,H05H

Claim:
1. An orthogonal pulse accelerator for a Time-of-Flight mass analyzer, comprising: an electrically-conductive first plate extending in a first plane; a second plate spaced from the first plate, the second plate extending in a second plane parallel to the first plane, the second plate comprising a grid that defines a plurality of apertures each having a first dimension extending in a first direction and a second dimension orthogonal to the first dimension, the first and second dimensions lying in the second plane and the second dimension being larger than the first dimension; an electrically-conductive third plate spaced from the second plate, the third plate comprising a second grid defining a second plurality of apertures; an electrically-conductive fourth plate spaced from the third plate, the fourth plate comprising a third grid defining a third plurality of apertures; and a voltage source configured to apply a constant voltage to the fourth plate during operation of the mass analyzer, wherein the first and second plates are positioned in the Time-of-Flight mass analyzer to receive, during operation of the mass analyzer, an ion beam propagating in the first direction in a region between the first and second plates while a first electric field between the first and second plates is essentially zero, and the orthogonal pulse accelerator directs ions in the ion beam through the plurality of apertures of the second plate when a second electric field is applied between the first and second plates, where ions passing through the plurality of apertures of the second plate are directed through the second plurality of apertures of the third plate and through the third plurality of apertures of the fourth plate.