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公开(公告)号：US20240234123A1
公开(公告)日：2024-07-11
申请号：US18037582
申请日：2021-11-17
发明人： Bruce COLLINGS , James HAGER , Yang KANG , Bradley B. SCHNEIDER
CPC分类号： H01J49/4215 , H01J49/0031 , H01J49/24 , H01J49/0086
摘要： A mass spectrometer comprises a first mass filter for receiving a plurality of ions and having a transmission bandwidth configured to allow transmission of ions having m/z ratios within a desired range, and a second mass filter that is disposed downstream of the first mass filter for selecting ions having a target m/z value within a transmission window thereof for mass analysis. The transmission bandwidth of the first mass filter encompasses at least two m/z ratios of interest such that one of said m/z ratios corresponds to said target m/z value within the transmission window of said second mass filter.
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公开(公告)号：US20220254619A1
公开(公告)日：2022-08-11
申请号：US17622568
申请日：2020-07-22
发明人： Bruce COLLINGS , Pascal MARTIN
摘要： In one aspect, a method of modulating transmission of ions in a mass spectrometer is disclosed, which comprises generating an ion beam comprising a plurality of ions, directing the ion beam to an ion optic positioned in the path of the ion beam, wherein the ion optic includes at least one opening through which the ions can pass, and applying one or more voltage pulses at a selected duty cycle to said ion optic so as to obtain a desired attenuation of brightness of the ion beam passing through the ion optic, where a pulse width of said voltage pulses at said selected duty cycle is determined by identifying a pulse width on a calibration normalized ion intensity versus pulse width relation for said ions that corresponds to said desired attenuation on an ideal normalized ion intensity versus pulse width relation for said ions.
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3.发明申请公开(公告)号：US20220028677A1
公开(公告)日：2022-01-27
申请号：US17312907
申请日：2019-12-12
发明人： Bruce COLLINGS
摘要： Methods and apparatus are disclosed for reducing ion reflections between multipole segments in a mass spectrometer by matching the effective potential between the two segments. Mass spectrometers having at least two multipole segments separated from each other along a longitudinal axis of the mass spectrometer such that a boundary region exists through which ions are drawn from an upstream segment to a downstream segment, and wherein each multipole segment further includes a set of spaced-apart rod-shaped electrodes disposed around the longitudinal axis and having a field radius defined by an inscribed circle between the innermost portions of each electrode. Effective potential matching can be achieved by either supplying RF signals of different amplitudes to each segment and/or by modifying the field strength of the segments. In one embodiment, the multipole segments are configured such that the upstream multipole segment has a smaller field radius than the downstream segment.
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