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:
Oct. 09, 2012
Filed:
Jul. 21, 2011
Ari K. Tuchman, Palo Alto, CA (US);
John K. Stockton, Redwood City, CA (US);
Ari K. Tuchman, Palo Alto, CA (US);
John K. Stockton, Redwood City, CA (US);
Entanglement Technologies, Inc., Burlingame, CA (US);
Abstract
A method and device for measuring trace levels of particles in an air sample is described. A device operating in a gradiometer configuration with two cavities built from a monolithic structure and utilizing a single probe laser, provides common mode subtraction of acoustic, vibrational, laser intensity and other noise sources, which allows sensitivity more closely approaching the quantum limit. Differential measurements between the two cavities occur simultaneously, which reduces errors due to cavity drift. Absorptive gradiometry can therefore provide noise immune detection for trace gasses, including broad linewidth absorbers where frequency-noise immune schemes are not practical. Differential measurements can be used for background subtraction, sensing vapor plum gradients and determining vapor plume propagation direction.