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:
Aug. 11, 1987
Filed:
Dec. 24, 1984
John T Meek, Mercer County, NJ (US);
Gerald W Stockton, Bucks County, PA (US);
American Cyanamid Company, Stamford, CT (US);
Abstract
A Fourier transform ion cyclotron resonance (ICR) mass spectrometer, with a vacuum housing comprising three differentially pumped regions allows spatial separation of the processes for generation, translocation, and detection of the ionic species. The ion source provides inlets for solid, liquid, and gaseous samples from direct injection or chromatographic interfaces. Provision is made for ionization by electron impact, chemical ionization, fast atom bombardment, and laser ionization. A system of electrostatic lenses accelerates, focusses, and decelerates the ions for transmission to the ion detector. The mass analyzer includes an ion cyclotron resonance cell in which the ionic motions are detected by amplification of a small 'image' current induced in the walls of the cell and made to flow through external detection circuitry. The characteristic frequencies of the ionic motions are revealed by Fourier transformation of the digitized image current, and related to the ionic masses by a simple algebraic calibration function. High resolution and accuracy in the measured masses are achieved through the ultra high vacuum in the analyzer region, and the use of very large data tables for the digital representation of the image current. Such large data arrays (typically 512K words) require the use of a high speed array processor for the Fourier transformation and other mathematical processing, and high capacity magnetic storage media for the mass spectral data arrays. Electronic circuitry achieves an extremely large dynamic range in the ICR mass measurement.