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. 27, 2001
Filed:
Aug. 28, 1998
Yasuaki Takada, Kodaira, JP;
Takayuki Nabeshima, Kokubunji, JP;
Minoru Sakairi, Tokorozawa, JP;
Yuichiro Hashimoto, Kokubunji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method for performing a mass calibration under an application of a desired ion peak position of mass spectrum attained by a mass scanning of ions of substance having a known value of m/z and the known value of m/z is added with a step for ejecting an amount of unnecessary ions not contributing to the aforesaid mass calibration accumulated in the aforesaid ion trap type mass analysis region prior to the aforesaid mass scanning operation. An accumulation of a large amount of unnecessary ions in the ion trap type mass analysis region is restricted, a disturbance of electric field in the ion trap mass analysis region generated under an influence of a spatial charge caused by accumulation of the unnecessary ions can be prevented and the aforesaid mass calibration can be performed in an easy and accurate manner.