Device for transmitting and returning light and apparatus and method of manufacture

• US 5,257,338 A
• Filed: 05/22/1992
• Issued: 10/26/1993
• Est. Priority Date: 05/22/1992
• Status: Expired due to Term

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Biomedical Sensors Limited (Allegro Biodiesel Corp.)
• Inventors: Markle, David R.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Ngo, John
• Application Number:
  US07/887,457
• Time in Patent Office: 522 Days
• Field of Search: 385/14, 385/12, 385/33, 385/34, 385/37, 385/117, 385/119, 385/123, 372/6, 128/4-6, 250/227.11, 359/900
• US Class Current: 385/125
• CPC Class Codes: G02B 6/02033 Core or cladding made from organic material, e.g. polymeric material G02B1/04 takes precedence
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A device for transmitting and returning light comprising an elongate light transmissive flexible polymer fiber with a longitudinal axis, first and second ends normal to the axis for passing light therebetween and a returner shaped and sized to fit the second end with a face positioned to return light transmitted therethrough. A method and apparatus for manufacturing the device are also disclosed.

Claims

1. A device for transmitting and returning light comprising:

an elongate light transmissive member having an axis along the longitude thereof, which elongate light transmissive member is a flexible polymer fiber having first and second ends substantially normal to the axis for passing light therebetween, and

a returner shaped and sized to fit the second end with a face positioned for returning light transmitted through the elongate light transmissive member, the face disposed substantially normal to the axis and embedded within the second end.

2. A device according to claim 1 wherein a holder is placed substantially parallel to the returner to securely encapsulate the embedded returner at the second end and the holder terminates the second end so that the polymer encapsulates the returner to complete the second end.

3. A device according to claim 1 wherein the flexible polymer fiber is a clad fiber.

4. A device according to claim 3 wherein the clad fiber has a core of polymethylmethacrylate polymer and a cladding of fluorinated polymer.

5. A device according to claim 4 wherein the clad fiber and the returner each have a substantially circular cross section with the diameter of the returner being substantially equal to that of the diameter of the clad fiber and the returner is embedded a distance about 1 to 2 diameters from the second end.

6. A device according to claim 5 wherein the returner has a melting point substantially higher than the melting point of the clad fiber.

7. A method for manufacturing a device for transmitting and returning light, which device comprises an elongate light transmissive flexible member having an axis along the longitude thereof, which elongate light transmissive member is a flexible polymer fiber having first and second ends substantially normal to the axis for passing light therebetween;

and a returner shaped and sized to fit the second end with a face positioned for returning the light transmitted through the elongate light transmissive member, which returner has a melting point substantially higher than the melting point of the elongate light transmissive member, the face being disposed substantially normal to the axis and embedded within the second and, which method comprises the following steps;

placing a tube having a cross sectional shape similar to that of the elongate light transmissive member 11 along the axis, the tube being sized to receive the elongate light transmissive member for telescopic conjugation therewithin;

aligning the returner along the axis with its face substantially normal thereto for placement upon the second end of the elongate light transmissive member;

telescopically urging the tube, the elongate light transmissive member and the returner with the tube coaxially about the elongate light transmissive member and with the returner against the second end;

heating the tube, the elongate light transmissive member and the returner, and

embedding the returner within the second end without melting or deforming the tube.

8. A method according to claim 7 including the added step of aligning a holder along the axis substantially normal thereto for placement on the second end of the elongate light transmissive member and near the returner but distal thereof;

telescopically urging the tube, the elongate light transmissive member with the returner in the tube coaxially thereabout against the second end;

heating a vacuum pick up for the holder to complete the device for transmitting and returning light, and

securing the holder with a vacuum tube and applying the holder to the second end.

9. An apparatus for manufacturing a device for transmitting and returning light, which device comprises an elongate light transmissive flexible member with an axis along the longitude thereof, which elongate light transmissive member is aa flexible polymer fiber having first and second ends substantially normal to the axis for passing light therebetween, a returner shaped and sized to fit the second end with a face positioned for returning a substantial portion of the light transmitted through the elongate light transmissive member, the returner having a melting point substantially higher than the melting point of the elongate light transmissive member, the face disposed substantially normal to the axis and embedded within the second end, the elongate light transmissive member and the returner having cross sections of a similar size, and a holder placed substantially parallel to the returner to secure the embedded returner at the second end;

which apparatus, comprises;

a tube having a cross sectional shape similar to that of the elongate light transmissive member positioned along the axis, the tube being sized to receive the elongate light transmissive member for telescopic conjugation therewithin;

means for aligning the face along the axis substantially normal thereto for placement upon the second end of the elongate light transmissive member;

means for telescopically urging the tube, the elongate light transmissive member and the returner with the tube coaxially about the elongate light transmissive member and with the returner against the second end; and

a heater placed about the tube, the elongate light transmissive member and the returner thereby allowing the returner to be embedded within the second end without melting or deforming the tube.

10. An apparatus according to claim 9 wherein the tube has an internal cross section larger than the cross-section of the device for transmitting and returning light for permitting removal of the device from the tube.

11. An apparatus according to claim 9 wherein the tube is made of a relatively nonconductive material.

12. An apparatus according to claim 9 wherein the tube is circular in cross section.