Patent classifications
H01J49/066
Ions Funnels Having Improved Pressure Distribution and Flow Characteristics
The present disclosure is directed to an ion funnel and associated systems, where the ion funnel includes a plurality of electrodes each define an opening having an associated inner dimension and receive a RF voltage. The associated inner dimensions progressively reduce in size from approximately a first inner dimension to approximately a second inner dimension. The electrodes define a slope parameter with respect to adjacent electrodes, which is less than 0.04 for at least a majority of the electrodes. Additional systems and methods are provided for transferring ions from an ion funnel to an ion mobility device having a pressure greater than that of the ion funnel, for selectively transferring ions from the ion funnel to the ion mobility device, and for stripping ions of certain molecules adducted thereto during transfer.
Ion funnels and systems incorporating ion funnels
A method of reducing fragmentation of ions generated from a sample during transport of the ions through an ion transport apparatus that comprises an ion funnel portion, comprises: applying a selected DC potential difference between an outlet end of the ion transport apparatus and an exit ion lens that is disposed adjacent to the outlet end, wherein a sign of the selected DC potential difference is chosen so as to accelerate the ions from the outlet end of the ion transport apparatus towards and through the exit ion lens.
MASS SPECTROMETER COMPRISING A RADIO FREQUENCY ION GUIDE HAVING CONTINUOUS ELECTRODES
The invention relates to a mass spectrometer, comprising an ion guide having a plurality of electrodes that are supplied with a radio frequency voltage to facilitate radial confinement of ions in an internal volume defined by inward facing surfaces of the electrodes, the internal volume including a first section having a variable radial diameter along a longitudinal axis of the ion guide, in which the electrodes are helically wound, and an adjacent second section having a substantially constant radial diameter along the longitudinal axis, wherein the electrodes extend from the first section to the second section continuously. The continuous nature of the ion guide electrodes facilitates in particular unhindered axial propagation of ions through the assembly and prevents ion losses during their transmission through different compartments of the mass spectrometer.
METHODS FOR TRANSFERRING IONS IN A MASS SPECTROMETER
A method for transporting ions includes: providing an ion transfer tube having an axis and an internal bore having a width and a height less than the width; and providing an apparatus comprising a plurality of electrodes, each having a respective ion aperture having an aperture center, the apertures defining an ion channel configured to receive the ions from the ion transfer tube and to transport the ions to an outlet end of the apparatus, wherein at least a subset of the apertures progressively decrease in size in a direction towards the apparatus outlet end, wherein the ion transfer tube is configured such that the ion transfer tube axis is non-coincident with an axis of the ion channel or such that the width dimension of the ion transfer tube bore is parallel to a plane defined by the ion transfer tube axis and the ion channel axis.
Ion Funnels Having Improved Pressure Distribution and Flow Characteristics
The present disclosure is directed to an ion funnel and associated systems, where the ion funnel includes a plurality of electrodes each define an opening having an associated inner dimension and receive a RF voltage. The associated inner dimensions progressively reduce in size from approximately a first inner dimension to approximately a second inner dimension. The electrodes define an internal chamber having an outer dimension that reduces at a convergence angle of approximately 30 degrees for at least a majority of a length of the internal chamber from the first inner dimension to the second inner dimension. Additional systems and methods are provided for transferring ions from an ion funnel to an ion mobility device having a pressure greater than that of the ion funnel, for selectively transferring ions from the ion funnel to the ion mobility device, and for stripping ions of certain molecules adducted thereto during transfer.
COMPLEMENTED ION FUNNEL FOR MASS SPECTROMETER
A mass spectrometry method comprises: (1) introducing ions and gas into an first electrode section of an ion transport apparatus through a slot of an ion transfer tube, the ion tunnel section comprising a first longitudinal axis that is contained within a slot plane of the ion transfer tube, the first longitudinal axis not intersecting an outlet of the ion transfer tube, wherein the apparatus further comprises: (a) a second electrode section configured to receive the ions from the first electrode section and comprising a second longitudinal axis that is not coincident with the first longitudinal axis; and (b) an ion outlet aperture; (2) providing voltages to electrodes of the ion transport apparatus that urge the ions to migrate towards the first longitudinal axis within the first electrode section; and (3) exhausting gas through a port that is offset from the ion outlet aperture.
Methods and apparatus for ion transfer by ion bunching
A mass spectrometry method comprises: receiving a stream of ions at an inlet end of an ion transport device; accumulating a first portion of the ion stream at a first electrical potential well at a first position within the ion transport device between the inlet and outlet ends; creating a generally descending potential profile within the ion transport apparatus between a second position and the outlet end and, simultaneously, creating a second potential well at a third position within the ion transport apparatus, the second position disposed between the first position and the inlet end, the third position disposed between the second position and the inlet end; and transporting the accumulated first portion of the ion stream from the first position to the outlet end under the impetus of the generally descending potential profile and, simultaneously, accumulating a second portion of the ion stream at the second potential well.
Mass spectrometry ion funnel
An ion funnel fabricated from at least three faces that are each formed from a printed circuit board is described. In one aspect the faces are arranged edge to edge and there is provided a set of guard rails proximal to the edges to bias ions away from the edges. In another aspect slots are provided within the circuit board to facilitate an escape of gases from within the funnel.
Atmospheric pressure ion guide
Atmospheric pressure ion guides are provided. The atmospheric pressure ion guides can include a multi-ring electrode structure connecting a larger opening to a smaller opening and having a series of ring electrodes with decreasing diameter and voltage going from the larger opening to the smaller opening. The electrodes can be made from stainless steel or other suitable conductive material. The multi-ring electrode structure can be contained in a housing, such as a housing made from polyetheretherketone or other suitable thermosetting polymer. The atmospheric pressure ion guide can focus ions from an ion source for use with ion detection devices such as an ion mobility spectrometer or a mass spectrometer. Methods of using the atmospheric pressure ion guides are provided, for example to focus a plurality of ions to be injected into an ion detection device. The atmospheric pressure ion guides can increase the signal intensity of the ion detection device.
APPARATUSES AND METHODS FOR MERGING ION BEAMS
An ion beam lens and methods for combining ion beams are disclosed. Embodiments combine hyperthermal ion beams and can include layered three-dimensional electrodes with passageways through the electrodes, each electrode having a specified DC voltage and each passageway configured for passing an ion beam to an exit, the velocity vectors of the beams being primarily oriented along the lens' central axis upon exiting the passageways. Embodiments include nested electrode plates with curved ion beam passageways. In some embodiments each electrode plate has a charge different from the electrode plates adjacent to it, and in some embodiments every other electrode plate is charged with a first DC voltage and the remaining plates are charged with a second DC voltage different from the first DC voltage.