Fiber optic sensing device including pressure detection and human implantable construction

• US 5,089,697 A
• Filed: 01/11/1989
• Issued: 02/18/1992
• Est. Priority Date: 01/11/1989
• Status: Expired due to Fees

• Current Assignee: Otto J. Prohaska
• Original Assignee: Otto J. Prohaska
• Inventors: Prohaska, Otto J.
• Primary Examiner(s): Nelms, David C.
• Application Number:
  US07/296,060
• Time in Patent Office: 1,133 Days
• Field of Search: 250/227, 250/231 R, 250/231 P, 250/227.21, 250/231.1, 250/221, 250/227.15, 250/227.16, 250/227.14, 350/96.21, 350/96.15, 350/96.20, 73/705
• US Class Current: 250/227.21
• CPC Class Codes: A61B 5/02154 by optical transmission
• CPC Class Codes: G01D 5/268 using optical fibres G01D5/28 - G01D5/38 take precedence
• CPC Class Codes: G01L 1/24 by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet

Abstract

A fiber optic sensing device for use in a variety of different applications is disclosed. The fiber optic sensing device includes a light source and a first fiber optic waveguide for receiving light from the light source. A second fiber optic waveguide is provided for receiving light from the first fiber optic waveguide. The fiber optic sensing device further includes means mounting the first and second fiber optic waveguides for relative movement to vary the light transmitted between the first and second fiber optic waveguides. A sensor is provided for sensing the light transmitted between the first and second fiber optic waveguides.

Claims

1. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein said first and second fiber optic waveguides are constructed in a manner suitable for implantation in the human body.

2. The fiber optic sensing device of claim 1 wherein said light source is a light-emitting diode and wherein said sensor sensing the light transmitted between said first and second fiber optic waveguides includes a photodiode.

3. The fiber optic sensing device of claim 1 wherein said mounting means includes a photodiode connected at one end of one of said waveguides, said photodiode sensing light received by said one waveguide from said light source.

4. The fiber optic device of claim 1 wherein said first waveguide has a longitudinal central axis and an end face;

wherein said second waveguide has a longitudinal central axis and an end face positioned adjacent to said end face of said first waveguide; and

wherein said end faces of said waveguides are arranged and aligned in abutting relationship in said unexcited state.

5. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state; and

wherein said means mounting said first and second fiber optic waveguides includes a tubular-shaped housing in which said first and second fiber optic waveguides are disposed.

6. A fiber optic sensing device for sensing static pressure comprising:

a housing;

a diaphragm means sealably connected in a side wall of said housing for sensing static pressure at a location outside of said housing;

a light source;

a first fiber optic waveguide in said housing for receiving light from said light source;

a second fiber optic waveguide mounted in said housing in an unexcited state and movable relative to said first fiber optic waveguide for receiving light from said first fiber optic waveguide, the movement between said first and second fiber optic waveguides varying as a function of the movement of the diaphragm means responsive to changes in static pressure at the location outside said housing; and

a sensor sensing light transmitted between said first and second fiber optic waveguides, the light transmitted between said first and second fiber optic waveguides being at a maximum at said unexcited state and varying as a function of the extent of movement between said first and second fiber optic waveguides, and thereby varying as a function of the static pressure at the location outside of said housing;

wherein said first and second fiber optic waveguides are constructed in a manner suitable for implantation in the human body.

7. The fiber optic sensing device of claim 6 wherein said diaphragm means includes a membrane in which mechanical deformation is functionally related to a pressure applied thereto.

8. The fiber optic sensing device of claim 6 wherein said light source is a light-emitting diode and wherein said sensor for sensing light transmitted between said first and second fiber optic waveguides includes a photodiode.

9. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state; and

wherein said mounting means includes a mirror assembly pivotally connected at one end of said second waveguide.

10. The fiber optic sensing device of claim 9 wherein said sensing means is connected with one of said waveguides and senses light reflected from said mirror assembly.

11. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein mounting means includes a substrate on which said first and second waveguides are mounted;

wherein said mounting means further includes a housing enclosing the waveguides and the substrate.

12. The fiber optic sensing device of claim 11 wherein said sensing means is disposed in at least a portion of said substrate.

13. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein said mounting means includes a substrate on which said first and second waveguides are mounted; and

wherein said substrate is a silicon wafer.

14. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein said mounting means includes a substrate on which said first and second waveguides are mounted; and

wherein said waveguide includes a wall forming layer disposed in said substrate, said wall forming layer and said substrate forming a channel therebetween for directing light received from said light source.

15. The fiber optic sensing device of claim 14 wherein said sensing means is disposed in at least a portion of said substrate.

16. The fiber optic sensing device of claim 14 wherein said mounting means further includes a housing enclosing the waveguides and the substrate.

17. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein said first waveguide has a longitudinal central axis and an end face;

wherein said second waveguide has a longitudinal central axis and an end face positioned adjacent to said end face of said first waveguide;

wherein said end faces of said waveguides are arranged and aligned in abutting relationship in said unexcited state; and

wherein the end face of one of said waveguides extends in a direction unperpendicular to the longitudinal axis of said waveguide.

18. The fiber optic device of claim 17 wherein the end face of the other of said waveguides extends in a direction unperpendicular to the longitudinal axis of said waveguide.

19. The fiber optic device of claim 17 wherein the end face of the other of said waveguides extends in a direction perpendicular to the longitudinal axis of said waveguide.

20. A fiber optic sensing device comprising:

a light source;

a first fiber optic waveguide for receiving light from said light source;

a second fiber optic waveguide for receiving light from said first fiber optic waveguide;

mounting means for mounting said first and second fiber optic waveguides in an unexcited state and for allowing relative movement between said first waveguide and said second waveguide in response to a stimuli to vary the light transmitted between said first and second fiber optic wave guides; and

sensing means for sensing the light transmitted between said first and second fiber optic waveguides;

wherein the light transmitted between said first and second fiber optic waveguides is a maximum at said unexcited state;

wherein said first waveguide has a longitudinal central axis and an end face;

wherein said second waveguide has a longitudinal central axis and an end face positioned adjacent to said end face of said first waveguide;

wherein said end faces of said waveguides are arranged and aligned in abutting relationship in said unexcited state; and

wherein the end face of one of said waveguides is rounded.

21. The fiber optic device of claim 20 wherein the end face of the other of said waveguides is rounded.

22. A fiber optic sensing device for sensing static pressure comprising:

a housing;

diaphragm means sealably connected in a side wall of said housing for sensing static pressure at a location outside of said housing;

a light source;

a first fiber optic waveguide in said housing for receiving light from said light source;

a second fiber optic waveguide mounted in said housing in an unexcited state and movable relative to said first fiber optic waveguide for receiving light from said first fiber optic waveguide, the movement between said first and second fiber optic waveguides varying as a function of the movement of the diaphragm means responsive to changes in static pressure at the location outside said housing; and

a sensor sensing light transmitted between said first and second fiber optic waveguides, the light transmitted between said first and second fiber optic waveguides being at a maximum at said unexcited state and varying as a function of the extent of movement between said first and second fiber optic waveguides, and thereby varying as a function of the static pressure at the location outside of said housing;

wherein said housing is of a tubular shape in which said first and second fiber optic waveguides are disposed.