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:
Mar. 28, 1995
Filed:
Jun. 14, 1993
Robert J Ferran, San Diego, CA (US);
Ferran Scientific, San Diego, CA (US);
Abstract
A residual gas sensor, suitable for mounting within an low pressure chamber, includes an array of quadrupoles formed from a plurality of parallel rods mounted in a cantilevered fashion in a glass seal. Sixteen parallel rods form an array of nine quadrupoles with adjacent quadrupoles sharing adjacent rods. A filament emitting electrons ionize gas molecules present in the low pressure chamber. These ions enter channels in the center of each quadrupole and are accelerated towards a collector having a surface mounted within each channel of each quadrupole. Voltages are applied to the rods thereby creating an identical electric field within the channels of each quadrupoles of the array. By varying the voltages applied to the rods, the electric field within the channels can be tuned to permit only ions having a specific mass-to-charge ratio to make contact with the collector. By analyzing the current generated by the ions making contact with the collector at different voltages, the presence and quantity of gases present in the low pressure chamber can be determined.