The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 01, 2022
Filed:
May. 31, 2018
Shimadzu Corporation, Kyoto, JP;
Kazuma Maeda, Kyoto, JP;
Daisuke Okumura, Kyoto, JP;
SHIMADZU CORPORATION, Kyoto, JP;
Abstract
When a Q-TOF type mass spectrometer is operated in an MSmode, a controller (), at the time of measurement, controls voltage generators (to) such that only a V voltage (radio-frequency voltage for mass separation) and a direct-current bias voltage are applied to main rod electrodes of a quadrupole mass filter () without application of a U voltage (direct-current voltage for mass separation). During a measurement preparation period between a plurality of measurements to obtain one mass spectrum, the controller () controls a U voltage generator () so as to apply the U voltage to the main rod electrodes of the quadrupole mass filter (). Accordingly, a direct-current electric field is formed between adjacent main rod electrodes around an ion optical axis (C) due to a potential difference, and electric charges accumulated in rod holders () holding the main rod electrodes are rapidly removed by an effect of this electric field. As a result, it is possible to eliminate a charge-up that has not been eliminated by a conventional method in which a polarity of a direct-current bias voltage applied to the rod electrodes is merely reversed.