Sensing apparatus employing variable coupler fiberoptic sensor

• US 6,907,148 B2
• Filed: 02/26/2002
• Issued: 06/14/2005
• Est. Priority Date: 08/24/1998
• Status: Expired due to Fees

• Current Assignee: Empirical Technologies Corporation
• Original Assignee: Empirical Technologies Corporation
• Inventors: Adkins, Charles, Gerdt, David W., Baruch, Martin C.
• Primary Examiner(s): KANG, JULIANA K
• Application Number:
  US10/082,290
• Publication Number:
  US 20020146204A1
• Time in Patent Office: 1,204 Days
• Field of Search: 385 12- 13, 385/31, 385/32, 385/39, 385/43
• US Class Current: 385/12
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 2562/146 for optical coupling
• CPC Class Codes: A61B 2562/168 Fluid filled sensor housings
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: G01D 5/35345 using Amplitude variations to detect the measured quantity
• CPC Class Codes: G01L 1/243 using means for applying force perpendicular to the fibre axis
• CPC Class Codes: G02B 6/2856 formed or shaped by thermal heating means, e.g. splitting, branching and/or combining elements

Abstract

A fiberoptic sensing apparatus comprises a fiberoptic coupler in which a plurality of optical fibers are joined through a fused coupling region, the optical fibers including at least one input optical fiber and a plurality of output optical fibers, the fiberoptic coupler distributing light incident to the input optical fiber among the plurality of output optical fibers. The coupler is mounted to a support member and configured such that at least a portion of the coupling region can be deflected to change the light distribution among the output fibers without putting the coupling region under tension. A fluid column is cooperative with a deflection member disposed to deflect the portion of the coupling region.

Claims

1. Fiberoptic sensing apparatus, comprising:

a fiberoptic coupler in which a plurality of optical fibers are joined through a fused coupling region, said optical fibers including at least one input optical fiber and a plurality of output optical fibers, said fiberoptic coupler distributing light incident to said input optical fiber among said plurality of output optical fibers;

a support member;

said coupler being mounted to said support member and configured such that at least a portion of said coupling region can be deflected to change the light distribution among said output fibers with said coupling region being under substantially no tension;

a fluid column cooperative with a deflection member disposed to deflect said portion of said coupling region;

a transducer coupled to said fluid column, said transducer converting pressure fluctuations from an external source into pressure changes in said fluid column, causing said deflection member to deflect said portion of said coupling regions, said transducer being disposed at a first end of said fluid column, and said deflection member being disposed at a second end of said fluid column; and

a pressurizing device which sets an initial fluid pressure of said fluid column.

2. The apparatus of claim 1, wherein said pressurizing device is connected to said fluid column at a position between said first and second ends.

3. The apparatus of claim 1, wherein said fluid column is a gaseous column.

4. The apparatus of claim 1, wherein at least part of said fluid column is contained in a hose.

5. The apparatus of claim 1, further comprising:

a device optically coupled to said output optical fibers to detect the change of light distribution.

6. The apparatus of claim 5, further comprising:

a display connected to an output of said device.

7. The apparatus of claim 1, wherein said portion of said coupling region is substantially U-shaped.

8. The apparatus of claim 7, wherein said U-shaped portion lies substantially in a plane and is disposed to be deflected along a direction perpendicular to said plane.

9. An apparatus for monitoring acoustic activity or motion of an object, comprising:

a support member having a surface configured to support the object;

a transducer associated with said support member and capable of transmitting pressure fluctuations due to acoustic activity or motion of the supported object;

a fiberoptic sensor having a fused-fiber coupling region supported such that at least a portion of said coupling region can be deflected to change an output of said sensor without said coupling region being under substantially no tension; and

a fluid column coupled to said transducer and cooperative with a deflection member to transmit pressure fluctuations from said transducer to said deflection member, said deflection member deflecting said portion of said coupling region.

10. The apparatus of claim 9, wherein said transducer is disposed at a first end of said fluid column, and said deflection member is disposed at a second end of said fluid column.

11. The apparatus of claim 9, wherein at least a portion of said fluid column is contained in a hose.

12. The apparatus of claim 9, wherein said transducer includes a bladder having an interior space in communication with said fluid column.

13. The apparatus of claim 12, wherein said bladder has a resiliently deformable portion which transmits external pressure fluctuations to said interior space.

14. The apparatus of claim 9, wherein said support member has a recessed or cut-out portion in which at least a portion of said transducer is received.

15. The apparatus of claim 14, wherein said transducer includes a bladder, a portion of which protrudes from said surface of said support member to engage the object to be monitored.

16. The apparatus of claim 15, wherein at least a portion of said fluid column is contained in a hose.

17. The apparatus of claim 16, wherein said support member has a recessed or cut-out portion in which at least a portion of said hose is received.

18. The apparatus of claim 9, further comprising:

a device optically coupled to said fiberoptic sensor to detect output changes of said sensor due to the deflection of said portion of said coupling region.

19. The apparatus of claim 18, further comprising a display connected to an output of said device.

20. The apparatus of claim 9, wherein said portion of said coupling region is substantially U-shaped.

21. The apparatus of claim 20, wherein said U-shaped portion lies substantially in a plane and is disposed to be deflected along a direction perpendicular to said plane.