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:
Jul. 03, 2001
Filed:
Dec. 31, 1998
Joseph C. Alfano, Lisle, IL (US);
Michael J. Fehr, Lisle, IL (US);
Martin R. Godfrey, Elburn, IL (US);
John E. Hoots, St. Charles, IL (US);
Karen R. Tubergen, Mt. Prospect, IL (US);
James E. Whitten, Naperville, IL (US);
Narasimha M. Rao, Naperville, IL (US);
Nalco Chemical Company, Naperville, IL (US);
Abstract
A solid-state fluorometry instrument is provided. The instrument is based on either diode laser or light-emitting diode (LED) excitation sources that are capable of being used in a wide range of applications. The solid-state diode laser based fluorometer instrument monitors fluorescent tracers, particularly suitable for industrial water sample stream applications. Using the instrument, a solid-state diode laser or light-emitting diode (LED) is used as an excitation source to excite fluorescent tracer molecules. The fluorescence resulting from the diode laser excitation is imaged with a lens onto a silicon photodiode detector. An optical filter is placed between the sample cell and the photodiode detector to reject scattered laser light. The output from the photodiode is amplified to produce an output voltage proportional to the quantity of fluorescence striking the photodiode detector. Since fluorescence is proportional to the concentration of a fluorophore present in the sample stream, continuous monitoring of a voltage output may be performed which further allows real time measurement of concentration of a fluorescent tracer present in, for example, a sample stream.