Optical sensor for detecting accumulation of a material

Patent metadata

Field	Value
Publication number	US-10175167-B2
Application number	US-201715471852-A
Country	US
Kind code	B2
Filing date	Mar 28, 2017
Priority date	Mar 28, 2017
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

A sensor for detecting the level of accumulation of a material along an axis in a fluid environment, the sensor comprising (a) an optically transparent body having a third refractive index and an exposed surface defining a length extending at least partially in the direction of the axis; (b) at least one light delivery source for delivering light to the body such that the light is distributed along the length of the exposed surface; and at least one light receiver for receiving reflected light from the length of the exposed surface, wherein the amount of the reflected light depends on the level of the material accumulated along the length of the exposed surface.

First claim

What is claimed is:

1. A sensor for detecting the level of accumulation of a material along an axis in a fluid environment, said material having a first refractive index and said fluid having a second refractive index different from said first refractive index, said sensor comprising:
a single optically transparent body having a third refractive index and at least one exposed surface defining a length, said exposed surface being configured to be exposed to said environment and positioned with said length extending at least partially in the direction of said axis, said at least one exposed surface being configured to reflect light from at least one light delivery source to at least one light receiver in a single reflection;
said at least one light delivery source for delivering transmitted light to said body such that said transmitted light is distributed along said length of said exposed surface;
said at least one light receiver for receiving reflected light from said length of said exposed surface, wherein the amount of said reflected light depends on the level of said material accumulated along said length of said exposed surface; and
wherein at least one of said transmitted light or said reflected light propagates at least partially in the direction of said axis.

2. The sensor of claim 1 , wherein said sensor is configured for measuring the level of accumulation of said material on a monitored surface, wherein said axis is perpendicular to said monitored surface.

3. The sensor of claim 2 , wherein said sensor is configured for measuring the level of ice accumulation, wherein said material is ice and said fluid is air, and said monitored surface is the edge of a wing component.

4. The sensor of claim 2 , wherein said sensor is configured for measuring the level of scale on a vessel, wherein said material is scale and said fluid is liquid, and said monitored surface is the wall of said vessel.

5. The sensor of claim 1 , wherein said at least one light receiver comprises a two-dimensional array of receivers.

6. The sensor of claim 1 , wherein said sensor is configured for measuring the level of a liquid in a container, wherein said material is said liquid, and said axis is vertical.

7. The sensor of claim 6 , wherein said environment is flammable or explosive.

8. The sensor of claim 1 , wherein said at least one exposed surface extends at an angle with said axis of accumulation.

9. The sensor of claim 1 , wherein said at least one exposed surface is a single planar surface.

10. The sensor of claim 9 , wherein said at least one exposed surface extends at a 45 degree angle with said axis of accumulation.

11. The sensor of claim 9 , wherein said at least one light delivery source comprises a single optical fiber optically coupled to a lens.

12. The sensor of claim 9 , wherein said at least one light delivery source comprises a plurality of optical fibers, each optically coupled to a lens.

13. The sensor of claim 1 , wherein said at least one light receiver comprises a plurality of opto-electric devices (OEDs), each configured for receiving light reflected from a certain portion along said length of said exposed surface, and converting said received light to an electrical signal, said at least one light receiver also comprises electrical conduit for transmitting said electrical signal of each OED to a controller.

14. The sensor of claim 1 , wherein said at least one light receiver comprises a lens for focusing said light reflected from said exposed surface to at least one OED for converting the focused light to an electrical signal, and an electrical conduit for transmitting said electrical signal of said OED to a controller.

15. The sensor of claim 1 , wherein said at least one exposed surface comprises a plurality of planar facets forming a curved exposed surface and defining a convergent point of light reflected by said facets.

16. The sensor of claim 15 , wherein said at least one light delivery source comprises an optical fiber optically coupled to each facet.

17. The sensor of claim 14 , wherein said at least one light receiver comprises a single OED disposed proximate said convergent point and an electrical conduit from said OED to said controller.

18. The sensor of claim 1 , wherein said at least one light receiver comprises a light conduit for transmitting said reflected light to a discrete OED.

19. The sensor of claim 1 , wherein said exposed surface is discrete from said body.

20. The sensor of claim 19 , wherein said exposed surface is replaceable.

21. The sensor of claim 1 , further comprising:
a controller to determine said level of accumulation of said material along said length of said exposed surface based on at least said reflected light.

22. The sensor of claim 21 , wherein said reflected light comprises at least a first portion of said light reflected at said exposed surface as a function of said first and third refractive indexes, and a second portion of said light reflected at said exposed surface as a function of said second and third refractive indexes, and wherein said controller determines the level of accumulation of said material on said exposed surface based on the relative amounts of said first and second portions in said reflected light.

23. The sensor of claim 1 , wherein said at least one light delivery source is configured for delivering light to said body wherein the intensity of incident light on said exposed surface varies by less than 15% of the maximum intensity across the intensity profile.

24. The sensor of claim 1 , wherein at least one of said transmitted light or said reflected light is essentially parallel to said axis.

25. A method for detecting the level of accumulation of a material along an axis in a fluid environment, said material having a first refractive index and said fluid having a second refractive index different from said first refractive index, said method comprising:
transmitting at least one incident beam along a length of at least one exposed surface of a single optically transparent body having a third refractive index, said at least one exposed surface being configured to be exposed to said environment and positioned with said length extending at least partially in the direction of said axis, said at least one exposed surface being configured to reflect said incident light in a single reflection to create reflected light; and
receiving said reflected light from said length of said exposed surface, wherein the amount of said reflected light depends on the level of said material accumulated along said length of said exposed surface; and
wherein at least one of said incident light or said reflected light propagates at least partially in the direction of said axis.

26. The method of claim 25 , wherein at least one of said incident light or said reflected light is essentially parallel to said axis.

27. A sensor in combination with am structure having a monitored surface, said sensor for detecting the level of accumulation of a material along an axis in a fluid environment, wherein said axis is perpendicular to said monitored surface, said material having a first refractive index and said fluid having a second refractive index different from said first refractive index, said sensor comprising:
a single optically transparent body having a third refractive index and at least one exposed surface defining a length, said exposed surf

Assignees

• Te Connectivity Corp

Inventors

• Grinderslev Soren
• Stouklov Igor
• Benton Mark

Classifications

• G01B11/06

  for measuring thickness {; e.g. of sheet material (thickness measurement by thermal means G01B21/085)} · CPC title

• G01N21/4133 Primary

  Refractometers, e.g. differential · CPC title

• G01N2201/0826

  Fibre array at source, distributing · CPC title

• G08B19/02

  Alarm responsive to formation or anticipated formation of ice · CPC title

• G01N21/94 Primary

  Investigating contamination, e.g. dust (G01N21/85 takes precedence) · CPC title