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. 23, 1996
Filed:
Apr. 15, 1994
David A King, Palo Alto, CA (US);
Jens-Peter Seher, Stuttgart, DE;
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The presence of trace materials in a sample is detected using both macroscopic and microscopic properties. A detector includes a light source and an optical resonator. The light source may be located either inside the resonance cavity of the resonator or outside the cavity, in which case it may be a semi-conductor such as a semi-conductor laser or a superluminescent diode. The detector also includes at least one reflective member that has a total internal reflection (TIR) surface and may be a passive device or an active gain element. Light from the light source is preferably focussed onto a single point of reflection on the TIR surface. The test sample is positioned within the evanescent field region of the TIR surface. Optical changes arising within the evanescent field region, such as excitation of fluorescence in the sample, changes in its refractive index, and changes in the resonant frequency of the optical resonator, are then detected. These changes are then sensed to determine the amount or at least presence of analyte located at the TIR surface.