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:
Apr. 06, 1999
Filed:
May. 28, 1997
David A Le Febre, Camino, CA (US);
UOP LLC, Des Plaines, IL (US);
Abstract
A very long sample cell for spectrophotometric measurements can be used to extend sensitivity to very low levels of gaseous components, under about 50 parts per billion. The cell is an optical fiber positioned within the annular space of a housing, with a gas stream flowing along the annular space. The outer surface of the fiber is coated with a material, e.g., an adsorbent which concentrates at least one component of the gas stream at the interface of the fiber and annular space. An indispensable prerequisite is that the coating have a refractive index greater than that of the optical fiber core. Radiation is propagated along the core of the fiber, and the evanescent wave passes through the adsorbed component, ultimately changing the radiation detected at the output end of the fiber according to the nature and concentration of the component.