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:
Jan. 06, 1987
Filed:
Oct. 27, 1983
Thomas B Lucatorto, Washington, DC (US);
Charles W Clark, Gaithersburg, MD (US);
Tom J Whitaker, Kennewick, WA (US);
Atom Sciences, Inc., Oak Ridge, TN (US);
Abstract
An ultrasensitive mass spectrometry method based on multiphoton sub-Doppler resonance ionization is used to measure abundance sensitivities. The method preferentially ionizes a selected isotope in a sample by using Doppler-free resonant multiphoton ionization to produce an enhanced ratio of selected isotopes. As necessary or desired, selected isotope ions are preferentially ionized by using a second Doppler-free resonant multiphoton ionization to provide an additional isotope enhancement. The ions produced are injected into a mass spectrometer (24). Isotopic spectrum analysis of the ions is performed by the spectrometer (24) and the ions are then detected by a detector (26) such as a particular photon multiplier capable of observing a single ion. In one embodiment, at least one of the steps of preferentially ionizing the selected isotope is accomplished by two counter propagating laser beams of slightly different frequencies.