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:
Mar. 02, 2021
Filed:
Apr. 10, 2019
The Boeing Company, Chicago, IL (US);
Eric Y. Chan, Mercer Island, WA (US);
Dennis G. Koshinz, Bellevue, WA (US);
The Boeing Company, Chicago, IL (US);
Abstract
A fuel sensing system utilizes non-contact plastic optical fiber (POF) to optically sense the level of liquid fuel in a fuel tank. In one implementation, the fuel level sensing system includes the following elements: (i) a high-speed and high-power red laser diode; (ii) an ultra-high-sensitivity photon-counting avalanche photodiode; and (iii) a large-diameter and large-numerical-aperture graded-index POF. The fuel level is sensed when the avalanche photodiode first detects impinging light reflected by the POF end face and then detects impinging light reflected by the fuel surface in response to emission of a laser pulse by the red laser diode. A time delay detection circuit calculates the time interval separating the respective times of arrival. A fuel level calculator calculates the fuel level based on the time interval provided by the time delay detection circuit.