Abstract: A mass spectrometer 1 includes a vacuum container 5 divided into a first chamber 51 containing an ion trap 3 and a second chamber 52 containing a time-of-flight mass spectrometer 4. The ion trap 3 is held within an ion-trap-holding space 610 surrounded by a wall 61. In this wall 61, a cooling-gas discharge port 64 is formed in addition to an introduction-side ion passage port 62 and an ejection-side ion passage port 63. A cooling gas supplied into an ion-capturing space 315 of the ion trap 3 is discharged from the ion-trap-holding space 610 through the three ports. The provision of the cooling-gas discharge port 64 reduces the amount of cooling gas flowing into the ejection-side ion passage port 63 and interfering with the ejection of ions from the ion trap 3 into the time-of-flight mass spectrometer 4. Consequently, the detection intensity of the ions is improved.

Abstract: A mass spectrometer 1 includes a vacuum container 5 divided into a first chamber 51 containing an ion trap 3 and a second chamber 52 containing a time-of-flight mass spectrometer 4. The ion trap 3 is held within an ion-trap-holding space 610 surrounded by a wall 61. In this wall 61, a cooling-gas discharge port 64 is formed in addition to an introduction-side ion passage port 62 and an ejection-side ion passage port 63. A cooling gas supplied into an ion-capturing space 315 of the ion trap 3 is discharged from the ion-trap-holding space 610 through the three ports. The provision of the cooling-gas discharge port 64 reduces the amount of cooling gas flowing into the ejection-side ion passage port 63 and interfering with the ejection of ions from the ion trap 3 into the time-of-flight mass spectrometer 4. Consequently, the detection intensity of the ions is improved.

Abstract: Provided is a time-of-flight mass spectrometer including: a loop-orbit defining electrode (21) including an outer electrode (211) and inner electrode (212) located on the outside and inside of a loop orbit, respectively; an ion inlet (22); an ion outlet (23) provided in either the outer or inner electrode; a loop-flight voltage applier (28) configured to apply loop-flight voltages to the outer and inner electrodes, respectively; a set of deflecting electrodes (24) facing each other across a section of an n-th loop orbit, where n is a predetermined number, the deflecting electrodes including a first portion (241) which faces the n-th loop orbit and a second portion (242) which includes other portions; and a voltage applier (29) configured to apply deflecting voltages to the first portion so as to reverse the drifting direction of the ions flying in the n-th loop orbit, and a voltage to the second portion so as to create the loop-flight electric field.

Abstract: Provided is a method for mass spectrometry in which ions to be analyzed are made to come in contact with a cooling gas in a cooling section, such as an ion trap 2, configured to perform the cooling of ions, and kinetic energy is subsequently imparted to the ions so as to introduce the ions into a flight space of a multi-turn time-of-flight mass separator 30 or similar device for separating ions according to their mass-to-charge ratios. According to the present invention, when a known or estimated number of charges of an ion to be analyzed is high, the amount of supply of the cooling gas to the cooling section is set to a lower level than when the number of charges is low. This operation improves the detection sensitivity for ions having large molecular weights and high numbers of charges.

Abstract: A mass spectrometer 1 includes a vacuum container 5 divided into a first chamber 51 containing an ion trap 3 and a second chamber 52 containing a time-of-flight mass spectrometer 4. The ion trap 3 is held within an ion-trap-holding space 610 surrounded by a wall 61. In this wall 61, a cooling-gas discharge port 64 is formed in addition to an introduction-side ion passage port 62 and an ejection-side ion passage port 63. A cooling gas supplied into an ion-capturing space 315 of the ion trap 3 is discharged from the ion-trap-holding space 610 through the three ports. The provision of the cooling-gas discharge port 64 reduces the amount of cooling gas flowing into the ejection-side ion passage port 63 and interfering with the ejection of ions from the ion trap 3 into the time-of-flight mass spectrometer 4. Consequently, the detection intensity of the ions is improved.

Abstract: To improve the reliability of mutual diagnosis in a cancer determination by machine learning, m/z values of ions originating from tumor markers or similar substances used in other related tests are stored in a particular m/z-value database. A spectrum information filtering section deletes signal intensities at the m/z values stored in the particular m/z-value database from a large number of mass spectra classified by the presence or absence of cancer. Using the data which remain after the deletion as training data, a training processor obtains training-result information and stores it in a training result database. A judgment processor similarly deletes signal intensities at the predetermined m/z values from mass spectrum data obtained for a target sample to be judged. Then, based on the training-result information stored in the training-result database, the judgment processor determines whether the target sample should be classified into a cancerous group or non-cancerous group.

Abstract: Provided is a time-of-flight mass spectrometer including: a loop-orbit defining electrode (21) including an outer electrode (211) and inner electrode (212) located on the outside and inside of a loop orbit, respectively; an ion inlet (22); an ion outlet (23) provided in either the outer or inner electrode; a loop-flight voltage applier (28) configured to apply loop-flight voltages to the outer and inner electrodes, respectively; a set of deflecting electrodes (24) facing each other across a section of an n-th loop orbit, where n is a predetermined number, the deflecting electrodes including a first portion (241) which faces the n-th loop orbit and a second portion (242) which includes other portions; and a voltage applier (29) configured to apply deflecting voltages to the first portion so as to reverse the drifting direction of the ions flying in the n-th loop orbit, and a voltage to the second portion so as to create the loop-flight electric field.

Abstract: A time-of-flight mass spectrometer includes a flight tube, an ion introduction unit that is connected to the flight tube, an ion detector that detects an ion flown in the flight tube, and a control unit that controls the ion introduction unit and the flight tube, wherein: the control unit sequentially changes an accumulation state of the ion to be introduced into the flight tube by the ion introduction unit, for a plurality of measurement processes performed repeatedly.

Abstract: Provided is a method for mass spectrometry in which ions to be analyzed are made to come in contact with a cooling gas in a cooling section, such as an ion trap 2, configured to perform the cooling of ions, and kinetic energy is subsequently imparted to the ions so as to introduce the ions into a flight space of a multi-turn time-of-flight mass separator 30 or similar device for separating ions according to their mass-to-charge ratios. According to the present invention, when a known or estimated number of charges of an ion to be analyzed is high, the amount of supply of the cooling gas to the cooling section is set to a lower level than when the number of charges is low. This operation improves the detection sensitivity for ions having large molecular weights and high numbers of charges.

Abstract: To compensate for the distortion of the loop-flight electric field with a higher level of accuracy, a multiturn time-of-flight mass spectrometer 1 includes: a main electrode 21 configured to generate, within a predetermined loop-flight space, a loop-flight electric field which is an electric field that makes an ion fly in a loop orbit multiple times, the main electrode having an opening 24 or 25 through which ions are introduced into or extracted from the loop-flight space; a compensating-electrode attachment part 23 made of an insulating material and fixed to the main electrode; and a compensating electrode 22 configured to compensate for a distortion of the loop-flight electric field which occurs in the vicinity of the opening, the compensating electrode being fixed to the compensating-electrode attachment part directly or via a substrate 221 and located in the vicinity of the opening.

Abstract: To compensate for the distortion of the loop-flight electric field with a higher level of accuracy, a multiturn time-of-flight mass spectrometer 1 includes: a main electrode 21 configured to generate, within a predetermined loop-flight space, a loop-flight electric field which is an electric field that makes an ion fly in a loop orbit multiple times, the main electrode having an opening 24 or 25 through which ions are introduced into or extracted from the loop-flight space; a compensating-electrode attachment part 23 made of an insulating material and fixed to the main electrode; and a compensating electrode 22 configured to compensate for a distortion of the loop-flight electric field which occurs in the vicinity of the opening, the compensating electrode being fixed to the compensating-electrode attachment part directly or via a substrate 221 and located in the vicinity of the opening.

Abstract: A time-of-flight mass spectrometer includes a flight tube, an ion introduction unit that is connected to the flight tube, an ion detector that detects an ion flown in the flight tube, and a control unit that controls the ion introduction unit and the flight tube, wherein: the control unit sequentially changes an accumulation state of the ion to be introduced into the flight tube by the ion introduction unit, for a plurality of measurement processes performed repeatedly.

Abstract: A microchannel plate (MCP) 41 in an ion detection section 4 multiplies electrons. An anode 42 detects those electrons and produces a current signal. An amplifier 44 converts this signal into a voltage signal. A low-pass filter 5A acting as a smoothing section 5 is located at the output end of the amplifier 44. A waveform-shaping time adjuster 6 adjusts the time constant of the low-pass filter 5A beforehand according to the response time of the MCP 41, mass-to-charge ratio of an ion species to be subjected to the measurement, and duration of the spread of the ion species which depends on device-specific parameters. A plurality of peaks which sequentially appear in the detection signal corresponding to one ion species are thereby smoothed into a single broad peak. Thus, the distinguishability between signal waves and noise components is improved.

Abstract: To improve the reliability of mutual diagnosis in a cancer determination by machine learning, m/z values of ions originating from tumor markers or similar substances used in other related tests are stored in a particular m/z-value database. A spectrum information filtering section deletes signal intensities at the m/z values stored in the particular m/z-value database from a large number of mass spectra classified by the presence or absence of cancer. Using the data which remain after the deletion as training data, a training processor obtains training-result information and stores it in a training result database. A judgment processor similarly deletes signal intensities at the predetermined m/z values from mass spectrum data obtained for a target sample to be judged. Then, based on the training-result information stored in the training-result database, the judgment processor determines whether the target sample should be classified into a cancerous group or non-cancerous group.

Abstract: A microchannel plate (MCP) 41 in an ion detection section 4 multiplies electrons. An anode 42 detects those electrons and produces a current signal. An amplifier 44 converts this signal into a voltage signal. A low-pass filter 5A acting as a smoothing section 5 is located at the output end of the amplifier 44. A waveform-shaping time adjuster 6 adjusts the time constant of the low-pass filter 5A beforehand according to the response time of the MCP 41, mass-to-charge ratio of an ion species to be subjected to the measurement, and duration of the spread of the ion species which depends on device-specific parameters. A plurality of peaks which sequentially appear in the detection signal corresponding to one ion species are thereby smoothed into a single broad peak. Thus, the distinguishability between signal waves and noise components is improved.

Abstract: A gate electrode (10A) used as a shutter gate includes a pair of conductive fixture members (131, 132) made of metal and identical in size attached to the inside of a rectangular opening (12) of a ceramic base (11), along with insulating fixture members (141, 142) made of ceramic attached to the inner sides of the conductive fixture members. Two comb electrodes (151, 152) as one pair have connecting portions (151a, 152a) adhered to the conductive fixture members (131, 132) as well as thin-wire electrodes whose distal ends are adhered to the insulating fixture members (141, 142). By setting length L of the opening (12) and width D of the conductive fixture members (131, 132) to appropriate values according to the coefficient of thermal expansion of each of those members, the elongation of the electrodes which accompanies an increase in temperature can be balanced by the increase in the distance between the adhered positions of the electrodes to prevent the electrodes from being excessively taut or slack.

Abstract: A gate electrode (10A) used as a shutter gate includes a pair of conductive fixture members (131, 132) made of metal and identical in size attached to the inside of a rectangular opening (12) of a ceramic base (11), along with insulating fixture members (141, 142) made of ceramic attached to the inner sides of the conductive fixture members. Two comb electrodes (151, 152) as one pair have connecting portions (151a, 152a) adhered to the conductive fixture members (131, 132) as well as thin-wire electrodes whose distal ends are adhered to the insulating fixture members (141, 142). By setting length L of the opening (12) and width D of the conductive fixture members (131, 132) to appropriate values according to the coefficient of thermal expansion of each of those members, the elongation of the electrodes which accompanies an increase in temperature can be balanced by the increase in the distance between the adhered positions of the electrodes to prevent the electrodes from being excessively taut or slack.

Abstract: Used as an ion beam guiding unit for introducing primary ions to the surface of the sample is an ion optical system of reflectron TOFMS for achieving time focusing including an orthogonal acceleration unit for accelerating the ions in the orthogonal direction, a flight space of a non-electric field, and an ion reflector for forming a reflecting electric field. A dual stage type is used as the ion reflector to superimpose the correction potential showing a predetermined non-linear potential distribution on the potential having a linear gradient of a uniform electric field at the side deeper than the second order focusing position that fulfills the Mamyrin solution, thereby correcting the temporal spread of ion packets emitted from the orthogonal acceleration unit until the deviation of third or higher order in energy, achieving high time focusing.

Abstract: Used as an ion beam guiding unit for introducing primary ions to the surface of the sample is an ion optical system of reflectron TOFMS for achieving time focusing including an orthogonal acceleration unit for accelerating the ions in the orthogonal direction, a flight space of a non-electric field, and an ion reflector for forming a reflecting electric field. A dual stage type is used as the ion reflector to superimpose the correction potential showing a predetermined non-linear potential distribution on the potential having a linear gradient of a uniform electric field at the side deeper than the second order focusing position that fulfills the Mamyrin solution, thereby correcting the temporal spread of ion packets emitted from the orthogonal acceleration unit until the deviation of third or higher order in energy, achieving high time focusing.

Abstract: A first mass analysis is executed in a condition that gas is not introduced into a loop-flight chamber (4), and a time-of-flight spectrum obtained in a data processor (12) is stored in a storage unit (13). Next, a second mass analysis is executed on the same sample as the one used in the first mass analysis in a condition that a valve (8) is opened and helium gas (He) is introduced into the loop-flight chamber (4), and the time-of-flight spectrum is obtained in the data processor (12). If different kinds of ions having the same m/z value exit, these ions form a single peak in the first time-of-flight spectrum, while these ions appear as separate peaks in the second time-of-flight spectrum even though they have the same m/z value. This is because, in the second mass analysis, the ions collide with the gas and have different times of flight depending on their difference in size.