A space-time buffer includes a plurality of discrete trapping regions and a controller. The plurality of discrete trapping regions is configured to trap ions as individual trapping regions or as combinations of trapping regions. The controller is configured to combine at least a portion of the plurality of trapping regions into a larger trap region; fill the larger trap region with a plurality of ions; split the larger trap region into individual trapping regions each containing a portion of the plurality of ions; and eject ions from the trapping regions.

A method of operating an instrument which comprises a first and second ion stores, comprising determining whether a target accumulation time for the second ion store is greater than a threshold accumulation time. When the target accumulation time is less than the threshold accumulation time, ions are accumulated within the second ion store using an accumulation time that is based on the target accumulation time. When the target accumulation time is greater than the threshold accumulation time, ions are accumulated within the first ion store using a first accumulation time that is based on a difference between the target accumulation time and the threshold accumulation time, the ions accumulated in the first ion store are passed to the second ion store, and further ions are accumulated within the second ion store using a second accumulation time that is based on the threshold accumulation time.

Ions ejected from a collision cell are detected by a detector. An evaluation unit generates a temporary calibration curve based on an intensity of a detection signal and evaluates an ion accumulation time of the collision cell based on the temporary calibration curve. When the evaluation unit determines signal saturation, the ion accumulation time of the collision cell is reduced. When the evaluation unit determines sensitivity insufficiency, the ion accumulation time of the collision cell is increased.

A spherical ion trap includes a substrate and an ion aperture; two RF electrodes in electrostatic communication with an ion trapping region; RF ground electrodes in electrostatic communication with the ion trapping region; and the ion trapping region bounded by opposing RF electrodes and the RF ground electrodes, such that: the ion trapping region is disposed within the ion aperture and receives ions that are selectively trapped in the ion trapping region in response to receipt of DC and RF voltages by the RF electrodes, and receipt of the DC voltages by RF ground electrodes, and the first RF electrode, the second RF electrode, the RF ground electrodes, and the ion trapping region are disposed in the same plane within the ion aperture.

In one aspect, a method of processing ions in a mass spectrometer is disclosed, which comprises trapping a plurality of ions having different mass-to-charge (m/z) ratios in a collision cell, releasing said ions from the collision cell in a descending order in m/z ratio, and receiving the ions in a mass analyzer having a plurality of rods to at least one of which an RF voltage is applied, where the RF voltage is varied from a first value to a lower second value as the released ions are received by the mass analyzer.

Provided herein are methods and systems for controlling the number of ions in a batch of ions accumulated in an ion trap. The ion trap comprises one or more detection electrodes configured to detect image current signals from ions accumulated within the ion trap. An ion or group of ions passed to the ion trap is caused to impact upon one or more of the detection electrode(s) of the ion trap so as to provide a detected signal. An ion current or charge of the ion or group of ions is determined from the detected signal, and the determined ion current or charge of the ion or group of ions is used to control the number of ions in a batch of ions subsequently accumulated in the ion trap.

A mass spectrometry method comprises: introducing a first packet of ions into an electrostatic trap mass analyzer through a set of electrostatic lenses, wherein, during the introducing of the first packet, either the lenses are operated in a first mode of operation or an injection voltage of a first pre-determined magnitude is applied to an electrode of the mass analyzer; mass analyzing the first ion packet using the mass analyzer; introducing a second packet of ions into the mass analyzer through the set of lenses, wherein, during the introducing of the second packet, either the lenses are operated in a second mode of operation or an injection voltage of a second pre-determined magnitude is applied to the electrode of the mass analyzer; and mass analyzing the second packet of ions using the electrostatic trap mass analyzer.

An ion trap mass spectrometer includes an ion trap including a first electrode and a second electrode different from the first electrode, a first voltage controller that periodically switches a DV voltage among DC voltages having a plurality of values and apply the DV voltages to the first electrode, and a second voltage controller that applies a sine-wave voltage to the second electrode when ions captured in the ion trap are dissociated.

In one aspect, a method of processing ions in a mass spectrometer is disclosed, which comprises trapping a plurality of ions having different mass-to-charge (m/z) ratios in a collision cell, releasing said ions from the collision cell in a descending order in m/z ratio, and receiving the ions in a mass analyzer having a plurality of rods to at least one of which an RF voltage is applied, where the RF voltage is varied from a first value to a lower second value as the released ions are received by the mass analyzer.

In one aspect, a method of modulating transmission of ions in a mass spectrometer is disclosed, which comprises generating an ion beam comprising a plurality of ions, directing the ion beam to an ion optic positioned in the path of the ion beam, wherein the ion optic includes at least one opening through which the ions can pass, and applying one or more voltage pulses at a selected duty cycle to said ion optic so as to obtain a desired attenuation of brightness of the ion beam passing through the ion optic, where a pulse width of said voltage pulses at said selected duty cycle is determined by identifying a pulse width on a calibration normalized ion intensity versus pulse width relation for said ions that corresponds to said desired attenuation on an ideal normalized ion intensity versus pulse width relation for said ions.