Abstract: Systems and methods are provided to perform dead time correction. An observed ion count rate is obtained using a non-paralyzable detection system of a mass spectrometer. The detection system includes an ion detector, a comparator/discriminator, a mono-stable circuit and a counter. The non-paralyzable detection system exhibits dead time extension at high count rates. The extension of the dead time occurs because the mono-stable circuit requires a rising edge to trigger and can only be triggered again after the output pulse from the comparator/discriminator has gone low. This allows a second comparator/discriminator pulse arriving just before the end of the dead time started by a first comparator/discriminator pulse to extend the dead time to the trailing edge of the second comparator/discriminator pulse. A true ion count rate is calculated by performing dead time correction of the observed ion count rate.

Abstract: A mass spectrometer and method is provided for a time-of-flight analyzer (TOF) having an accelerator stage with a plurality of electrodes to receive and accelerate a plurality of ions, and a drift chamber downstream of the accelerator stage for receiving at least a portion of the accelerated ions. The TOF analyzer also has a pulser coupled to the accelerator stage for applying one or more voltages to the plurality of electrodes and a controller coupled to the pulser to adjust one or more voltages applied to the electrodes to configure the accelerator stage to receive and accelerate positive and negative ions during different cycles of an ion detection period.

Abstract: In one aspect, a mass spectrometer is disclosed that includes a time-of-flight analyzer (TOF), which comprises an accelerator stage comprising a plurality of electrodes and adapted to receive and accelerate a plurality of ions, and a drift chamber disposed downstream of said accelerator stage for receiving at least a portion of the accelerated ions. The TOF analyzer further comprises a pulser coupled to the accelerator stage for applying one or more voltages to said plurality of electrodes, and a controller coupled to the pulser and adapted to cause the pulser to adjust said one or more voltages applied to the electrodes so as to configure the accelerator stage to receive and accelerate positive and negative ions during different cycles of an ion detection period.

Abstract: Systems and methods are provided to perform dead time correction. An observed ion count rate is obtained using a non-paralyzable detection system of a mass spectrometer. The detection system includes an ion detector, a comparator/discriminator, a mono-stable circuit and a counter. The non-paralyzable detection system exhibits dead time extension at high count rates. The extension of the dead time occurs because the mono-stable circuit requires a rising edge to trigger and can only be triggered again after the output pulse from the comparator/discriminator has gone low. This allows a second comparator/discriminator pulse arriving just before the end of the dead time started by a first comparator/discriminator pulse to extend the dead time to the trailing edge of the second comparator/discriminator pulse. A true ion count rate is calculated by performing dead time correction of the observed ion count rate.

Abstract: There is provided a pulser, a time of flight mass spectrometer system comprising the same, and a method of analyzing the ions using the pulser. The pulser comprises a first positive switch for coupling and decoupling a first electrode of the accelerator assembly to a first positive voltage; a first negative switch for coupling and decoupling the first electrode to a first negative voltage; and, a first bipolar switch for alternately coupling and decoupling the first electrode to a third voltage.

Abstract: There is provided a pulser, a time of flight mass spectrometer system comprising the same, and a method of analyzing the ions using the pulser. The pulser comprises a first positive switch for coupling and decoupling a first electrode of the accelerator assembly to a first positive voltage; a first negative switch for coupling and decoupling the first electrode to a first negative voltage; and, a first bipolar switch for alternately coupling and decoupling the first electrode to a third voltage.