Abstract: An ion trap time-of-flight mass spectrometer capable of obtaining highly-sensitive mass spectra even on the lower mass number side is realized. The ion trap time-of-flight mass spectrometer includes an ion source that operates at atmospheric pressure, an ion optical system for introducing the ions generated by the ion source into a vacuum chamber and converging the ions introduced into the vacuum chamber, an ion trap part for trapping ions in the vacuum chamber, a multipole part for converging the kinetic energy of the ions discharged from the ion trap, and a time-of-flight mass spectrometry part for measuring the ions discharged from the multipole part. The period of high-voltage pulses generated by an electrode provided in the time-of-flight mass spectrometry part can be changed depending on an ion content introduced into the multipole part.

Abstract: In a data acquisition system of ADC system, a log amplifier is provided at the pre-stage of an A/D converter, a signal amplified by the log amplifier having a nonlinear input-output characteristic is A/D-converted, and an adding operation of data is performed while reconverting a voltage value data which is converted to a nonlinear characteristic to data with a linear scale according to a table memory for reverse-log conversion. A known voltage value is inputted into the log amplifier to perform measurement, and calibration of the table memory is performed by storing the voltage value and the voltage value data after A/D-converted.

Abstract: An “ion trap-TOF/MS” capable of calibrating the observed mass for each of an ion trap and a TOF. In the ion trap-TOF/MS, sample ions having known mass numbers and ionized by an ion source are trapped within an ion trap. Auxiliary AC voltages having a frequency component ? are applied to the end cap electrodes of the ion trap to expel unwanted ions out of the ion trap. A measurement process is carried out by applying DC voltages to the ring electrode and the end cap electrodes to expel an ion remaining within the ion trap, and measuring the mass number of the expelled ion by the time-of-flight mass spectrometer. The measurement process is repeated while changing the frequency component ?, and the ion signal intensity measured by the time-of-flight mass spectrometer is compared with a previously stored threshold, thereby making calibration of the frequency component ? for the ion having the known mass number. Thus, the calibrating of the observed mass can be realized for each of the ion trap and the TOF.

Abstract: The present invention relates to a data processing device for mass spectrometry, in which measurements are performed in a high dynamic range without causing an overrange in an A/D converter in any TOF scan. A data acquisition circuit of a mass spectrometer includes an amplitude value computing circuit which measures and stores a maximum amplitude value of an ion detection signal, a gain control circuit for determining and setting a gain amount for the next measurement, and others. From the immediately preceding TOF scan data or TOF scan data plural times before, the maximum amplitude value of the ion detection signal is extracted. Then, before the next TOF scan, an optimum gain amount is determined based on the extracted maximum amplitude value to adjust the gain of the input signal, and the ion signal is sampled in the A/D converter.

Abstract: For the achievement of data transfer time reduction, removal of noise data, and analytical efficiency improvement in an ADC data processing function of a time-of-flight mass spectrometer, the mass spectrometer comprises a data acquisition circuit including: an A/D converter; a signal intensity addition memory that stores data of ion signals such as a time range and the number of measurements and performs an addition process; a voltage value frequency addition memory that performs an addition process of frequencies of voltage values of the predetermined time range and the number of measurements and stores addition results; a threshold level computation circuit that computes a predetermined threshold level from the results in the memory; a compression memory that extracts only data exceeding the threshold level from the data in the signal intensity addition memory; and a counter that controls a measurement time for data acquisition and the operation of each circuit.

Abstract: A mass spectrometer according to the present invention has an ionization source for generating ions; an ion trap for accumulating the ions; a time-of-flight mass spectrometer for performing mass spectrometry analysis on the ions by use of a flight time; a collision damping chamber disposed between the ion trap and the time-of-flight mass spectrometer and having a plurality of electrodes therein, which produce a multi-pole electric field, wherein a gas is introduced into the collision damping chamber to reduce kinetic energy of the ions ejected from the ion trap; and an ion transmission adjusting mechanism disposed between the ion trap and the collision damping chamber to allow or prevent injection of the ions from the ion trap to the collision damping chamber. The mass spectrometer provides greatly enhanced qualitative and quantitative analysis capabilities, as compared with conventional techniques.

Abstract: An “ion trap-TOF/MS” capable of calibrating the observed mass for each of an ion trap and a TOF. In the ion trap-TOF/MS, sample ions having known mass numbers and ionized by an ion source are trapped within an ion trap. Auxiliary AC voltages having a frequency component ? are applied to the end cap electrodes of the ion trap to expel unwanted ions out of the ion trap. A measurement process is carried out by applying DC voltages to the ring electrode and the end cap electrodes to expel an ion remaining within the ion trap, and measuring the mass number of the expelled ion by the time-of-flight mass spectrometer. The measurement process is repeated while changing the frequency component ?, and the ion signal intensity measured by the time-of-flight mass spectrometer is compared with a previously stored threshold, thereby making calibration of the frequency component ? for the ion having the known mass number. Thus, the calibrating of the observed mass can be realized for each of the ion trap and the TOF.

Abstract: A mass spectrometer according to the present invention has an ionization source for generating ions; an ion trap for accumulating the ions; a time-of-flight mass spectrometer for performing mass spectrometry analysis on the ions by use of a flight time; a collision damping chamber disposed between the ion trap and the time-of-flight mass spectrometer and having a plurality of electrodes therein, which produce a multi-pole electric field, wherein a gas is introduced into the collision damping chamber to reduce kinetic energy of the ions ejected from the ion trap; and an ion transmission adjusting mechanism disposed between the ion trap and the collision damping chamber to allow or prevent injection of the ions from the ion trap to the collision damping chamber. The mass spectrometer provides greatly enhanced qualitative and quantitative analysis capabilities, as compared with conventional techniques.