# US 12,770,848 B2 · Mass spectrometer and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,770,848 B2 - Document ID: US12770848B2 - Status: Granted - Kind: B2 - Application number: 18/678,332 - Filed: 2024-05-30 - Published: 2024-12-05 - Granted: 2026-10-20 - Earliest claimed: 2023-06-02 - Assignees: Truemass Ltd - Applicants: Truemass Ltd - Inventors: John Hoyes - Web page: https://patentgrep.com/patent/US12770848B2 ## CPC - H01J 49/0036: {Step by step routines describing the handling of the data generated during a measurement} - H01J 49/025: {Detectors specially adapted to particle spectrometers (data acquisition H01J49/0036; detectors per se G01T, e.g. G01T1/28, G01T1/29)} - H01J 49/067: {Ion lenses, apertures, skimmers} - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract A method of discriminating noise, the method implemented by a computer comprising a processor and a memory, the method comprising: obtaining a time-domain signal representative of a charge induced in an inductive charge detector by an ion moving in a charge-detection mass spectrometer, CDMS; transforming the time-domain signal into a frequency-domain spectrum comprising a series of frequency-amplitude pairs; and rejecting a particular frequency-amplitude pair of the series of frequency-amplitude pairs not having a respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs. ## Claims ### Claim 1 A method of discriminating noise, the method implemented by a computer comprising a processor and a memory, the method comprising: obtaining a time-domain signal representative of a charge induced in an inductive charge detector by an ion moving in a charge-detection mass spectrometer, CDMS; transforming the time-domain signal into a frequency-domain spectrum comprising a series of frequency-amplitude pairs; and rejecting a particular frequency-amplitude pair of the series of frequency-amplitude pairs not having a respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs. ### Claim 2 (depends on 1) The method according to claim 1, wherein obtaining the time-domain signal representative of the charge induced in the inductive detector by the ion moving in the CDMS comprises obtaining the time-domain signal representative of the charge induced in the inductive detector by a plurality of ions moving in the CDMS, optionally wherein the plurality of ions have mutually different mass to charge ratios. ### Claim 3 (depends on 1) The method according to claim 1, wherein obtaining the time-domain signal representative of the charge induced in the inductive detector by the ion moving in the CDMS comprises obtaining the time-domain signal representative of the charge induced in the inductive detector by the ion moving with constant speed in the CDMS. ### Claim 4 (depends on 1) The method according to claim 1, wherein obtaining the time-domain signal representative of the charge induced in the inductive detector by the ion moving in the CDMS comprises obtaining the time-domain signal representative of the charge induced in the inductive detector by the ion moving with harmonic motion in the CDMS. ### Claim 5 (depends on 1) The method according to claim 1, wherein transforming the time-domain signal into the frequency-domain spectrum comprising the series of frequency-amplitude pairs comprises transforming the time-domain signal into the frequency-domain spectrum comprising the series of frequency-amplitude pairs using a Fourier Transform, FT, such as a Fast Fourier Transform, FFT. ### Claim 6 (depends on 1) The method according to claim 1, wherein rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs within a predetermined frequency tolerance range. ### Claim 7 (depends on 1) The method according to claim 1, wherein rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs within a predetermined amplitude tolerance range. ### Claim 8 (depends on 1) The method according to claim 1, wherein rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises rejecting a particular frequency-amplitude pair of the series of frequency-amplitude pairs having a predetermined harmonic frequency-amplitude pair, preferably a predetermined third and/or higher respective harmonic frequency-amplitude pair, amongst the series of frequency-amplitude pairs. ### Claim 9 (depends on 1) The method according to claim 1, wherein rejecting the particular frequency-amplitude pair of the series of frequency-amplitude pairs not having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises rejecting a particular frequency-amplitude pair of the series of frequency-amplitude pairs not having a predetermined harmonic frequency-amplitude pair signature amongst the series of frequency-amplitude pairs. ### Claim 10 (depends on 1) The method according to claim 1, comprising retaining a particular frequency-amplitude pair of the series of frequency-amplitude pairs having a respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs. ### Claim 11 (depends on 10) The method according to claim 10, wherein retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs within a predetermined frequency tolerance range. ### Claim 12 (depends on 10) The method according to claim 10, wherein retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs within a predetermined amplitude tolerance range. ### Claim 13 (depends on 10) The method according to claim 10, wherein retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having a respective predetermined harmonic frequency-amplitude pair, preferably only a predetermined second harmonic frequency-amplitude pair, amongst the series of frequency-amplitude pairs. ### Claim 14 (depends on 10) The method according to claim 10, wherein retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having the respective harmonic frequency-amplitude pair amongst the series of frequency-amplitude pairs comprises retaining the particular frequency-amplitude pair of the series of frequency-amplitude pairs having a predetermined harmonic frequency-amplitude pair signature amongst the series of frequency-amplitude pairs. ### Claim 15 (depends on 10) The method according to claim 10, comprising calculating a mass-to-charge ratio of the ion using the frequency of the retained frequency-amplitude pair and optionally, using the frequency of the respective harmonic frequency-amplitude pair. ### Claim 16 (depends on 10) The method according to claim 10, comprising calculating a charge of the ion using the amplitude of the retained frequency-amplitude pair and optionally, using the amplitude of the respective harmonic frequency-amplitude pair. ### Claim 17 (depends on 1) The method according to claim 1, wherein obtaining the time-domain signal representative of the charge induced in the inductive charge detector by the ion moving in the CDMS comprises acquiring, using the CDMS, the time-domain signal representative of the charge induced in the inductive charge detector by the ion moving in the CDMS. ### Claim 18 (depends on 1) The method according to claim 1, comprising controlling the CDMS, for example in real-time, using the calculated mass to charge ratio of the ion and/or the charge of the ion. ### Claim 19 (depends on 1) A computer, comprising a processor and a memory, configured to implement a method according to claim 1; a computer program comprising instructions which, when executed by a computer, comprising a processor and a memory, cause the computer to perform a method according to claim 1; and/or a non-transient computer-readable storage medium comprising instructions which, when executed by a computer, comprising a processor and a memory, cause the computer to perform a method according to claim 1. ### Claim 20 (depends on 1) A charge detection mass spectrometer, CDMS, comprising: an electrostatic field ion trap, comprising a set of electrostatic electrodes including a first electrostatic electrode and a second electrostatic electrode, and an inductive charge detector, wherein the electrostatic field ion trap is configured to define, at least in part, an ion path via the inductive charge detector; and a computer, comprising a processor and a memory, configured to implement a method according to claim 1. ### Claim 21 (depends on 20) The CDMS according to claim 20, wherein the electrostatic field ion trap comprises and/or is an electrostatic sector field ion trap, wherein the set of electrostatic electrodes comprises and/or is a set of electrostatic sectors and optionally, wherein the first electrostatic electrode and the second electrostatic electrode are a first electrostatic sector and a second electrostatic sector, respectively. ### Claim 22 (depends on 21) The CDMS according to claim 21, comprising a set of electrostatic focus lenses, including a first focus lens, arranged to constrain, at least in part, the ion path in a first dimension, preferably wherein the first dimension is orthogonal to a direction of the ion path via the inductive charge detector. ### Claim 23 (depends on 21) The CDMS according to claim 21, comprising a lift device configured to increase an ion energy of ions to be introduced into the ion path, for example by pulsing the ions into the ion path, and optionally, wherein the lift device is configured to trap the ions to be introduced into the ion path. ### Claim 24 (depends on 20) The CDMS according to claim 20, wherein the electrostatic field ion trap comprises and/or is an electrostatic linear field ion trap, optionally wherein the first electrostatic electrode comprises and/or is a first reflecting or mirror electrode and optionally wherein the second electrostatic electrode comprises and/or is a second reflecting or mirror electrode. ### Claim 25 (depends on 20) The CDMS according to claim 20, wherein the electrostatic field ion trap comprises and/or is a curved trap.