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:
May. 14, 2002
Filed:
Dec. 21, 1999
Hongfeng Yin, San Jose, CA (US);
Catherine Templin, Portola Valley, CA (US);
Agilent Technologies, Inc., Palo Alto, CA (US);
Abstract
A system and method for measuring flow rate within a fluid-bearing passageway include introducing heat fluctuations into the flow and then non-invasively monitoring the effects of the heat fluctuations propagating to or from one or more interrogation regions. In one embodiment, the non-invasive monitoring detects fluctuations in the refractive index of the flowing fluid as a result of variations in the temperature of the fluid. In another embodiment, electrical conductivity of the fluid is monitored. The heat fluctuations may be introduced using an optical heat generator, such as an infrared laser, or may be introduced using an electrical member, such as a heater coil. Determining the refractive index along the interrogation region may be achieved by monitoring characteristics on an interference pattern, but other optical arrangements may be utilized.