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公开(公告)号：US11355332B2
公开(公告)日：2022-06-07
申请号：US16494126
申请日：2017-11-10
Applicant: ISOTOPX LTD.
Inventor： Anthony Michael Jones , Vadim Volkovoy , Damian Paul Tootell
Abstract: The use of a capacitor (22) to serve as the principal impedance in a negative feed-back loop in a voltage amplifier component (21) of a trans-impedance amplifier and actively controlling the amount of charge accumulated within the capacitor appropriately to improve the responsiveness and/or dynamic range of the amplifier. A switch (25) is electrically coupled to the inverting input terminal of the voltage amplifier and electrically isolated from the output terminal (23) of the voltage amplifier. The output voltage of the amplifier is proportional to the accumulation of charge, and the switch is operable to ‘reset’ the charge/voltage on the feedback capacitor, as desired. This arrangement decouples the structure of the switch from the output port of the voltage amplifier, and so avoids leakage currents and/or interfering voltage signals emanating from the switch structure and being felt at the output port of the voltage amplifier.
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公开(公告)号：US20240014022A1
公开(公告)日：2024-01-11
申请号：US18255837
申请日：2021-12-03
Applicant: ISOTOPX LTD
Inventor： Damian Paul TOOTELL , Anthony Michael JONES
CPC classification number: H01J49/022 , H01J49/0422 , H01J49/28 , H01J49/08
Abstract: An ion source (30) for a static gas mass spectrometer is described. The ion source (30) comprises: a source block (310) defining a volume V to receive a sample gas G; an electron source (320) in fluid communication with the source block (310) and configured to provide a flux of electrons E therein for ionising the sample gas G; a set of electrodes (330), including a first electrode (330A), disposed between the electron source (320) and the source block (310); and a controller (not shown) configured to control a voltage applied to the first electrode (330A) to attenuate the flux of the electrons E into the source block (310) during a first time period following receiving of the sample gas G in the source block (310) and to permit the flux of the electrons E into the source block (310) during a second time period following the first time period.
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公开(公告)号：US20200294751A1
公开(公告)日：2020-09-17
申请号：US16759400
申请日：2018-10-26
Applicant: ISOTOPX LTD.
Inventor： Damian Paul TOOTELL , Anthony Michael JONES
Abstract: An electron source in a gas-source mass spectrometer the electron source comprising: an electron emitter cathode presenting a thermionic electron emitter surface in communication with a gas-source chamber of the gas-source mass spectrometer for providing electrons there to; a heater element electrically isolated from the electron emitter cathode and arranged to be heated by an electrical current therein and to radiate heat to the electron emitter cathode sufficient to liberate electrons thermionically from said electron emitter surface, therewith to provide a source of electrons for use in ionising a gas the gas-source chamber.
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公开(公告)号：US20230028580A1
公开(公告)日：2023-01-26
申请号：US17868916
申请日：2022-07-20
Applicant: ISOTOPX LTD.
Inventor： Damian Paul TOOTELL , Anthony Michael JONES
Abstract: An electron source in a gas-source mass spectrometer the electron source comprising: an electron emitter cathode presenting a thermionic electron emitter surface in communication with a gas-source chamber of the gas-source mass spectrometer for providing electrons there to; a heater element electrically isolated from the electron emitter cathode and arranged to be heated by an electrical current therein and to radiate heat to the electron emitter cathode sufficient to liberate electrons thermionically from said electron emitter surface, therewith to provide a source of electrons for use in ionising a gas the gas-source chamber.
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公开(公告)号：US11232937B2
公开(公告)日：2022-01-25
申请号：US16494083
申请日：2017-11-10
Applicant: ISOTOPX LTD
Inventor： Vadim Volkovoy , Anthony Michael Jones , Damian Paul Tootell
Abstract: A capacitive trans-impedance amplifier comprising a voltage amplifier having an inverting input terminal for connection to an input current source. A feed-back capacitor is coupled between the inverting input terminal and the output terminal to accumulate charges received from the input current source and to generate a feed-back voltage accordingly. A calibration unit includes a calibration capacitor electrically coupled, via a calibration switch, to the inverting input terminal and electrically coupled to the feed-back capacitor. The calibration unit is operable to switch the calibration switch to a calibration state permitting a discharge of a quantity of charge from the calibration capacitor to the feed-back capacitor. The capacitive trans-impedance amplifier is arranged to determine a voltage generated across the feed-back capacitor while the calibration switch is in the calibration state and to determine a capacitance value (C=Q/V) for the feed-back capacitor according to the value of the generated voltage (V) and the quantity of charge (Q).
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公开(公告)号：US11764026B2
公开(公告)日：2023-09-19
申请号：US17868916
申请日：2022-07-20
Applicant: ISOTOPX LTD.
Inventor： Damian Paul Tootell , Anthony Michael Jones
CPC classification number: H01J27/205 , H01J1/22 , H01J1/28
Abstract: An electron source in a gas-source mass spectrometer the electron source comprising: an electron emitter cathode presenting a thermionic electron emitter surface in communication with a gas-source chamber of the gas-source mass spectrometer for providing electrons there to; a heater element electrically isolated from the electron emitter cathode and arranged to be heated by an electrical current therein and to radiate heat to the electron emitter cathode sufficient to liberate electrons thermionically from said electron emitter surface, therewith to provide a source of electrons for use in ionising a gas the gas-source chamber.
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公开(公告)号：US11756776B2
公开(公告)日：2023-09-12
申请号：US17553171
申请日：2021-12-16
Applicant: ISOTOPX LTD
Inventor： Vadim Volkovoy , Anthony Michael Jones , Damian Paul Tootell
CPC classification number: H01J49/025 , H03F1/08 , H03F1/303 , H03F1/34 , H03F3/45071 , H03F3/45475 , H03F3/70 , H03F2200/126 , H03F2200/129 , H03F2200/321 , H03F2200/471 , H03F2203/45116 , H03F2203/45512 , H03F2203/45536
Abstract: A capacitive trans-impedance amplifier comprising a voltage amplifier having an inverting input terminal for connection to an input current source. A feed-back capacitor is coupled between the inverting input terminal and the output terminal to accumulate charges received from the input current source and to generate a feed-back voltage accordingly. A calibration unit includes a calibration capacitor electrically coupled, via a calibration switch, to the inverting input terminal and electrically coupled to the feed-back capacitor. The calibration unit is operable to switch the calibration switch to a calibration state permitting a discharge of a quantity of charge from the calibration capacitor to the feed-back capacitor. The capacitive trans-impedance amplifier is arranged to determine a voltage generated across the feed-back capacitor while the calibration switch is in the calibration state and to determine a capacitance value (C=Q/V) for the feed-back capacitor according to the value of the generated voltage (V) and the quantity of charge (Q).
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公开(公告)号：US11430627B2
公开(公告)日：2022-08-30
申请号：US16759400
申请日：2018-10-26
Applicant: ISOTOPX LTD.
Inventor： Damian Paul Tootell , Anthony Michael Jones
Abstract: An electron source in a gas-source mass spectrometer the electron source comprising: an electron emitter cathode presenting a thermionic electron emitter surface in communication with a gas-source chamber of the gas-source mass spectrometer for providing electrons there to; a heater element electrically isolated from the electron emitter cathode and arranged to be heated by an electrical current therein and to radiate heat to the electron emitter cathode sufficient to liberate electrons thermionically from said electron emitter surface, therewith to provide a source of electrons for use in ionising a gas the gas-source chamber.
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公开(公告)号：US20220181134A1
公开(公告)日：2022-06-09
申请号：US17553171
申请日：2021-12-16
Applicant: ISOTOPX LTD
Inventor： Vadim Volkovoy , Anthony Michael Jones , Damian Paul Tootell
Abstract: A capacitive trans-impedance amplifier comprising a voltage amplifier having an inverting input terminal for connection to an input current source. A feed-back capacitor is coupled between the inverting input terminal and the output terminal to accumulate charges received from the input current source and to generate a feed-back voltage accordingly. A calibration unit includes a calibration capacitor electrically coupled, via a calibration switch, to the inverting input terminal and electrically coupled to the feed-back capacitor. The calibration unit is operable to switch the calibration switch to a calibration state permitting a discharge of a quantity of charge from the calibration capacitor to the feed-back capacitor. The capacitive trans-impedance amplifier is arranged to determine a voltage generated across the feed-back capacitor while the calibration switch is in the calibration state and to determine a capacitance value (C=Q/V) for the feed-back capacitor according to the value of the generated voltage (V) and the quantity of charge (Q).
