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:
Sep. 23, 2003
Filed:
Jan. 26, 2001
Yoshikatsu Umemura, Kyoto-fu, JP;
Shimadzu Corporation, Kyoto, JP;
Abstract
A method of producing a broad-band signal including a plurality of component frequencies of regular or irregular intervals, where the broad-band signal is used to apply an alternating voltage to the end cap electrodes of an ion trap mass spectrometer. The method includes the following steps: (S ) a sinusoidal signal having one of the component frequencies with 0° initial phase angle is generated; (S ) the sinusoidal signal is added to a current temporary superposed signal to produce an addition signal; (S ) the sinusoidal signal is subtracted from the current temporary superposed signal to produce a subtraction signal; (S -S ) either of the addition signal or the subtraction signal is selected that has a smaller amplitude as a next temporary superposed signal; and (S ) the steps are repeated for all the component frequencies.