Optical coupled sensors for harsh environments

• US 9,391,216 B2
• Filed: 06/05/2009
• Issued: 07/12/2016
• Est. Priority Date: 06/06/2008
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Orbital ATK Inc. (Northrop Grumman Corporation)
• Inventors: Papadopoulos, George
• Primary Examiner(s): LEE, JOHN R
• Application Number:
  US12/479,251
• Publication Number:
  US 20090302242A1
• Time in Patent Office: 2,594 Days
• Field of Search: 250/550, 250/552, 250/208.2, 250/227.14, 250/227.19, 250/573, 356/450, 737/77, 738/02, 738/62, 738/623.24
• US Class Current: 1/1
• CPC Class Codes: G01F 1/661 using light
• CPC Class Codes: G01N 2011/008 optical properties
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/02325 the optical elements not being integrated nor being directly associated with the device

Abstract

An optical sensor comprising a light source; a sensor substrate, arranged to receive a force to be detected, the sensor substrate including an interference pattern generator, optically coupled to the light source for receiving light from the light source, and generating an interference pattern, and a detector, optically coupled to the sensor substrate for receiving the interference pattern and providing a signal which can be used to determine the force applied to the sensor substrate.

Claims

1. An optical sensor comprising:

a light source;

a fixed sensor substrate, the sensor substrate including a pair of slits separated a predetermined distance apart, each slit illuminated by the light source after traveling through compressible or thermal turbulence in a fluid so as to generate an interference pattern that varies with time, the light intensity of which is converted to a pair of voltage signals by a pair of photodetectors optically aligned with the slits, and

a signal processor for performing cross-correlation of the two voltage signals output from the photodetectors, to determine a time separation between the two voltage signals, which can be used to determine the flow velocity of the fluid.