ALEXANDRIA, Va., Feb. 11 -- United States Patent no. 12,548,751, issued on Feb. 10, was assigned to SHIMADZU Corp. (Kyoto, Japan).
"Quadrupole mass spectrometer" was invented by Manabu Ueda (Kyoto, Japan), Hiroki Miyashiro (Kyoto, Japan) and Junichi Taniguchi (Kyoto, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A quadrupole mass spectrometer includes a quadrupole mass filter including: a main rod portion including four main rod electrodes; a pre-rod portion including four pre-rod electrodes, where, at an end opposite to the main rod portion, the four pre-rod electrodes are disposed to be aligned on an inscribed circle having the same radius centered on the ion optical axis, and, at the other end faci...