摘要:
A mass spectrometer is disclosed comprising a Time of Flight mass analyzer comprising an ion detector comprising an Analog to Digital Converter. Signals from the Analog to Digital Converter are digitized and the arrival time and intensity of ions are determined. The arrival time T0 and intensity S0 of each ion arrival event is converted into two separate intensities S(n),S(n+i) which are stored in neighboring time bins T(n), T(n+1).
摘要:
A Time of Flight mass analyser is disclosed comprising an ion detector comprising an Analogue to Digital Converter. Output signals from the ion detector are digitised and the arrival times and intensity values relating to ion arrival events are determined. If the determined arrival times from two signals fall within the same time window then the arrival times are added together in a weighted manner and the intensity values are combined.
摘要:
A Time of Flight mass analyser is disclosed comprising an ion detector comprising an Analogue to Digital Converter. Output signals from the ion detector are digitised and the arrival times and intensity values relating to ion arrival events are determined. If the determined arrival times from two signals fall within the same time window then the arrival times are added together in a weighted manner and the intensity values are combined.
摘要:
A mass spectrometer is disclosed comprising a Time of Flight mass analyser comprising an ion detector comprising an Analogue to Digital Converter. Signals from the Analogue to Digital Converter are digitised and the arrival time and intensity of ions are determined. The arrival time T0 and intensity S0 of each ion arrival event is converted into two separate intensities S(n),S(n+i) which are stored in neighbouring time bins T(n), T(n+1).
摘要:
A mass spectrometer is disclosed comprising a mass selective ion trap or mass analyzer arranged upstream of an ion guide. Ions are scanned out of the mass selective ion trap or mass analyzer and are received in one or more axial potential wells created or formed within the ion guide. One or more transient DC voltages or potentials are preferably applied to the ion guide in order to create a plurality of axial potential wells which are translated along the length of the ion guide. Ions are released in packets from the exit of the ion guide and are orthogonally acceleration into a drift or flight region of an orthogonal acceleration Time of Flight mass analyzer with a relatively high duty cycle.
摘要:
A collision or fragmentation cell is disclosed comprising a plurality of electrodes wherein a first RF voltage is applied to an upstream group of electrodes and a second different RF voltage is applied to a downstream group of electrodes. The radial confinement of parent ions entering the collision or fragmentation cell is optimized by the first RF voltage applied to the upstream group of electrodes and the radial confinement of daughter or fragment ions produced within the collision or fragmentation cell is optimized by the second different RF voltage applied to the downstream group of electrodes.
摘要:
A collision or fragmentation cell (4) is disclosed comprising a plurality of electrodes wherein a first RF voltage (7a) is applied to an upstream group of electrodes and a second different RF voltage (7b) is applied to a downstream group of electrodes. The radial confinement of parent ions entering the collision or fragmentation cell (4) is optimised by the first RF voltage applied to the upstream group of electrodes and the radial confinement of daughter or fragment ions produced within the collision or fragmentation cell (4) is optimised by the second different RF voltage applied to the downstream group of electrodes.
摘要:
A mass spectrometer is disclosed comprising an ion mobility spectrometer and an ion gate. A collision cell is arranged downstream of the ion gate. The operation of the ion mobility spectrometer and the ion gate are synchronised so that only ions having a particular mass to charge ratio and a desired charge state are onwardly transmitted to the collision cell.
摘要:
A mass spectrometer includes an ion mobility spectrometer or separator arranged upstream of a collision or fragmentation cell. Ions are separated according to their ion mobility within the ion mobility spectrometer or separator. The kinetic energy of the ions exiting the ion mobility spectrometer or separator is increased substantially linearly with time in order to optimize the fragmentation energy of ions as they enter the collision or fragmentation cell. During the time that the potential of the ion mobility spectrometer or separator is being varied, the potential of ion-optical components upstream of the ion mobility spectrometer or separator such as an ion source, ion guide, quadrupole mass filter, optional second collision or fragmentation cell and an ion trapping device are kept constant.
摘要:
A mass spectrometer is disclosed comprising a quadrupole rod set ion guide or mass filter device (6). A broadband frequency signal (10) having one or more notches (11a, 11b, 11c) is applied to the rods of the quadrupole rod set (6). The notched broadband frequency signal (10) causes undesired ions to be resonantly ejected from the ion guide (6). The notched broadband frequency signal (10) has frequency components missing which correspond with the resonance frequency of ions which are desired to be onwardly transmitted. The ion guide or mass filter device (6) enables a plurality of desired ions having different mass to charge ratios to be simultaneously transmitted by the ion guide or mass filter device (6) whilst other ions are resonantly ejected from the ion guide or mass filter device (6).