Radiation resistant spectrometer interface

• US 8,482,729 B2
• Filed: 09/17/2010
• Issued: 07/09/2013
• Est. Priority Date: 10/30/2009
• Status: Expired due to Fees

• Current Assignee: Hutchinson Technology Incorporated (TDK Corporation)
• Original Assignee: Hutchinson Technology Incorporated (TDK Corporation)
• Inventors: Johnson, Robert A., Maher, Michael D., Scheele, Bryan J., Schmitz, Roger W., Kasel, Dustin L.
• Primary Examiner(s): Toatley, Gregory J
• Assistant Examiner(s): PHILLIPS, RUFUS L
• Application Number:
  US12/885,211
• Publication Number:
  US 20110102791A1
• Time in Patent Office: 1,026 Days
• Field of Search: 356/326, 356/317, 356/318, 356/417, 2504581-4612, 422 8207- 8208, 436/172, 600/317
• US Class Current: 356/300
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0264 Electrical interface; User interface
• CPC Class Codes: G01J 3/027 Control of working procedures of a spectrometer; Failure detection; Bandwidth calculation
• CPC Class Codes: G01J 3/0275 making use of sensor-related data, e.g. for identification of sensor parts or optical elements
• CPC Class Codes: G01J 3/0291 Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry

Abstract

Devices, systems, and methods for measuring tissue oxygen saturation are disclosed. An illustrative spectrometer for interfacing an optical sensor with a display unit includes a number of measurement radiation sources, a number of radiation source fibers each optically coupled to one of the measurement radiation sources, a reflected radiation fiber optically coupled to the optical sensor, a measurement radiation output fiber including an image fiber, and a radiation mixing bar intermediate the radiation source fibers and the measurement radiation output fiber.

Claims

1. A spectrometer for interfacing an optical sensor with a display unit, the spectrometer comprising:

a plurality of measurement radiation sources;

a plurality of radiation source fibers, each radiation source fiber optically coupled to one of the plurality of measurement radiation sources;

a reflected radiation fiber optically coupled to the optical sensor;

a measurement radiation output fiber comprised of an image fiber;

a radiation mixing bar intermediate the plurality of radiation source fibers and the measurement radiation output fiber, an input end of the radiation mixing bar optically coupled with the plurality of radiation source fibers and an output end of the radiation mixing bar optically coupled with the measurement radiation output fiber;

a reference radiation fiber having an input end optically coupled to the output end of the radiation mixing bar and an output end optically coupled to an attenuator;

a shield housing that is electrically conductive to provide electromagnetic interference shielding, each of the plurality of measurement radiation sources, the plurality of radiation source fibers, the radiation mixing bar, and the reference radiation fiber within the shield housing,

wherein the radiation mixing bar is optically coupled to at least one of the plurality of radiation source fibers and the measurement radiation output fiber via a film coupler, and

wherein a shim surrounds at least a portion of the film coupler.

2. The spectrometer of claim 1, wherein the attenuator comprises a scattering media and an aperture.

3. The spectrometer of claim 2, wherein:

the scattering media has input and output ends separated by at least one side surface; and

the scattering media is frictionally mounted within an opening such that at least a portion of the side surface is separated from the opening by an air gap.

4. The spectrometer of claim 3, wherein the opening is sized and shaped to provide at least three contact areas and at least three air gaps along the side surface of the scattering media.

5. The spectrometer of claim 1, further including:

a fiber holder having at least one fiber aperture, the fiber aperture having a plurality of grooves;

wherein at least one of the reflected radiation fiber, the reference radiation fiber and the measurement radiation output fiber bundle centrally located and adhesively secured within the fiber aperture.

6. The spectrometer of claim 5, further including:

a reflected radiation photo diode;

a reference radiation photo diode;

a processor board for controlling the measurement radiation sources and converting reflected radiation and reference radiation signals into electrical signals;

the processor board having side edges separated by proximal and distal end edges;

the reflected radiation and reference radiation photo diodes mounted on the proximal end edge of the processor board;

a plurality of contact sockets electrically connected to the processor board, each contact socket having a distal end protruding through an opening in the fiber holder; and

a seal boot intermediate the opening and the distal ends of the contact sockets.

7. The spectrometer of claim 1, further including a radiation mixing housing, the radiation mixing bar centrally located within the radiation mixing housing;

wherein a space between the radiation mixing bar and radiation mixing housing is filled with a layer of bubble-filled epoxy.

8. The spectrometer of claim 7, wherein the radiation mixing bar has a square-shaped cross section.

9. The spectrometer of claim 1, wherein the radiation source fibers are image fibers.

10. The spectrometer of claim 1, further comprising:

an electrical connector configured to releasably connect the spectrometer to the display unit via an electrical cable; and

an optical connector configured to releasably connect the spectrometer to the optical sensor via an optical cable.

11. The spectrometer of claim 10, wherein the optical cable comprises a radiation shielding covering an optical fiber, the radiation shielding comprising a tungsten-filled thermoplastic.

12. A spectrometer for interfacing an optical sensor with a display unit, the spectrometer comprising:

a plurality of measurement radiation sources;

a source optics housing, the plurality of measurement radiation sources within the source optics housing;

a plurality of radiation source fibers;

a radiation source fiber housing, the plurality of a radiation source fibers within the radiation source fiber housing;

a plurality of source optics coupling each source fiber to one of the plurality of measurement radiation sources;

a measurement radiation output fiber;

a reference radiation fiber;

a reflected radiation fiber optically coupled to the optical sensor;

a radiation mixing bar;

a radiation mixing housing, the radiation mixing bar within the mixing bar housing;

the radiation source fibers being optically coupled to an input end of the mixing bar;

the measurement and reference radiation fibers being optically coupled to an output end of the mixing bar;

a shield housing that is electrically conductive to provide electromagnetic interference shielding;

the source optics housing, radiation source fiber housing, and the radiation mixing housing located within the shield housing in a serial arrangement;

the source optics housing, radiation source fiber housing, and the radiation mixing housing housings being supported and aligned with respect to each other in the serial arrangement by a plurality of pins; and

a first shim located between the radiation source fiber housing and the radiation mixing housing, the first shim at least partially surrounding a first film coupler between the radiation mixing bar and the plurality of radiation source fibers;

a second shim at least partially surrounding a second film coupler between the radiation mixing bar and both of the measurement radiation output fiber and the reference radiation fiber.

13. A spectrometer for interfacing an optical sensor with a display unit, the spectrometer comprising:

a plurality of radiation sources;

a plurality of radiation source fibers optically coupled to the radiation sources, the plurality of a radiation source fibers within a radiation source fiber housing;

a radiation mixing bar optically coupling the radiation source fibers to measurement radiation and reference radiation fibers, the radiation mixing bar within the radiation mixing housing;

a first shim located between the radiation source fiber housing and the radiation mixing housing, the first shim at least partially surrounding a first film coupler between the radiation mixing bar and the plurality of radiation source fibers;

a second shim at least partially surrounding a second film coupler between the radiation mixing bar and both of the measurement radiation output fiber and the reference radiation fiber

photo diodes for receiving reference radiation from the radiation sources and reflected radiation from the optical sensor;

a processor board for controlling the radiation sources and processing signals received from the photo diodes;

a shield housing that is electrically conductive to provide electromagnetic interference shielding, the radiation sources, radiation source fibers, radiation mixing bar, photo diodes and processor board being substantially entirely contained within the shield housing;

an electrical connector configured to releasably connect the spectrometer to the display unit via an electrical cable; and

an optical connector configured to releasably connect the spectrometer to the optical sensor via an optical cable.

14. The spectrometer of claim 13, wherein the optical cable has at least one optical fiber and a radiation shielding covering over the optical fiber.

15. The spectrometer of claim 14, wherein the radiation shielding covering comprises a tungsten-filled thermoplastic.

16. The spectrometer of claim 13, further including a fiber holder for supporting the measurement radiation and reference radiation fibers, the fiber holder being electrically coupled to the shield housing.

17. The spectrometer of claim 16, wherein the fiber holder is electrically coupled to the conductive housing by a conductive gasket.

18. The spectrometer of claim 17, wherein the conductive gasket is a length of conductor-filled elastomer joined at the ends with a conductive pin.

19. A spectrometer for interfacing an optical sensor with a display unit, the spectrometer comprising:

a plurality of measurement radiation sources;

a plurality of radiation source fibers, each radiation source fiber optically coupled to one of the plurality of measurement radiation sources;

a radiation source fiber housing, the plurality of a radiation source fibers within the radiation source fiber housing;

a reflected radiation fiber optically connectable to the optical sensor;

a measurement radiation output fiber comprised of an image fiber;

a radiation mixing bar intermediate the plurality of radiation source fibers and the measurement radiation output fiber;

a radiation mixing housing, the radiation mixing bar within the radiation mixing housing;

a reference radiation fiber optically coupled to an attenuator;

a first shim located between the radiation source fiber housing and the radiation mixing housing, the first shim at least partially surrounding a first film coupler between the radiation mixing bar and the plurality of radiation source fibers;

a second shim at least partially surrounding a second film coupler between the radiation mixing bar and both of the measurement radiation output fiber and the reference radiation fiber; and

a shield housing that is electrically conductive, the shield housing providing electromagnetic interference shielding to the plurality of measurement radiation sources, the plurality of radiation source fibers, and the radiation mixing bar.

20. The spectrometer of claim 19, further comprising:

an electrical connector configured to connect the spectrometer to the display unit via an electrical cable; and

an optical connector configured to connect the spectrometer to the optical sensor via an optical cable.