WO2001042838A1

WO2001042838A1 - Methods and apparatus for packaging fiber gratings to provide temperature compensation

Info

Publication number: WO2001042838A1
Application number: PCT/US2000/028813
Authority: WO
Inventors: Jeffrey E. Cortright; Candace J. Quinn
Original assignee: Corning Incorporated
Priority date: 1999-12-13
Filing date: 2000-10-18
Publication date: 2001-06-14
Also published as: AU2423401A; TW554186B

Abstract

Passive temperature compensated package for short-period fiber gratings (18) and other optical components and techniques for forming the packages are described. In one aspect, a hollow tube (14) having a negative coefficient of thermal expansion (CTE) with a seal (20) and plug (24) at each end is employed to form an athermalized hollow tube package. According to another aspect, a hollow tube having a negative CTE with a shelf section at each end surrounds an optical fiber containing a short-period grating. The hollow tube is sealed at each end with a fused frit. According to another aspect, two channel members having a negative CTE are joined together to form an athermalized two-piece package. The channel members include longitudinal channels for sealing the two-piece package with a frit and epoxy at each end. According to another aspect, a substrate having a longitudinal channel and transverse channels having a negative CTE is employed to form an athermalized open channel package.

Description

METHODS AND APPARATUS FOR PACKAGING FIBER GRATINGS TO PROVIDE TEMPERATURE COMPENSATION

FIELD OF THE INVENTION The present invention relates generally to improvements in packaging for fiber optic components. More specifically, the present invention relates to methods and apparatus for packaging fiber gratings, filters, and other fiber optic components to provide athermalization, support, or protection.

BACKGROUND OF THE INVENTION Fiber gratings are periodic variations in the refractive index of a length of optical fiber. Such gratings have an index of modulation along the waveguiding axis of the fiber, and may be formed by writing with ultraviolet (UV) radiation, etching, or other mechanisms for making periodic perturbations. Short period, or Bragg fiber gratings, are particularly sensitive to temperature changes which, through thermal expansion of the optical fiber, cause changes in the refractive index of the optical fiber.

Changes in grating spacing and changes in the refractive index with temperature variations cause undesirable wavelength shifts in the device.

For many applications, fiber gratings must operate over large temperature ranges with minimal change in spectral properties. While the peak loss of the grating will change with temperature, the primary effect of a temperature change is a shift in peak wavelength. This temperature dependence can be compensated for by attaching the fiber grating to a substrate with a negative coefficient of thermal expansion. In one approach, fiber gratings are athermalized, or temperature compensated, by attaching them to a small bar of β eucryptite, a ceramic substrate with a negative coefficient of thermal expansion (CTE). A frit of at least two compositions attaches the optical fiber to the substrate and an epoxy deposit provides strain relief. The fiber grating attached to the substrate is then typically embedded in a protective fluorogel coating and enclosed in an hermetically sealed metal box to provide protection from the effects of humidity. This design depends upon integral bonding of the frit to a flat surface with mismatched CTEs. Stresses are created at the interface between the flat surface and the frit. The manufacture of this package involves a large number of process steps and involves a labor intensive process. Accordingly, it would be highly advantageous to provide a passive temperature compensating package assembly for fiber gratings which provides for ease of manufacturing, increased reliability, and a single frit composition.

SUMMARY OF THE INVENTION The present invention provides advantageous methods and apparatus for packaging fiber gratings and other fiber optic components to provide athermalization, support, or protection. According to one aspect of the invention, a hollow tube having a negative CTE with a seal and a plug at each end is employed to form an athermalized hollow tube package.

According to another aspect of the invention, a hollow tube having a negative CTE with a shelf section at each end is employed to form an athermalized shelf tube package. The hollow tube surrounds an optical fiber containing a fiber grating, and is sealed at each end. One suitable seal is a copper alumino silicate frit fused to each shelf section.

According to another aspect of the invention, two channel members having a negative CTE are joined together to form an athermalized two-piece package. The channel members include longitudinal channels for containing an optical fiber and include transverse channels for sealing the two-piece package with a frit and epoxy at each end. According to another aspect of the invention, a substrate with channels having a negative CTE is employed to form an athermalized open channel package. The channels provide for mechanical locking of a frit and epoxy.

A more complete understanding of the present invention, as well as further features and advantages of the invention, will be apparent from the following detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 A is a cross-sectional view of an athermalized hollow tube package in accordance with the present invention; Fig. IB is a flowchart of a method of forming the athermalized hollow tube package of Fig. 1A in accordance with the present invention;

Fig. 2A shows an isometric view of an athermalized shelf tube package in accordance with the present invention;

Fig. 2B is a flowchart of a method of forming the athermalized shelf tube package of Fig. 2A in accordance with the present invention;

Fig. 3 A is a cross-sectional view of an athermalized two-piece package in accordance with the present invention;

Figs. 3B and 3C show, respectively, top and side views of a housing member of the two-piece package of Fig. 3 A; Fig. 4A is a view of an athermalized open channel package in accordance with the present invention; and

Fig. 4B is a flowchart of a method of forming the open channel package of Fig. 4A in accordance with the present invention.

DETAILED DESCRIPTION

The present invention now will be described more fully with reference to the accompanying drawings, in which several currently preferred embodiments of the invention are shown. However, this invention may be embodied in various forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these representative embodiments are described in detail so that this disclosure will be thorough and complete, and will fully convey the scope, structure, operation, functionality, and potential of applicability of the invention to those skilled in the art.

As described in detail below, the present invention provides advantageous methods and apparatus for packaging fiber gratings written into an optical fiber to provide athermalization, support, and protection. In the embodiments of the present invention described below, one or more seals are utilized with the packages of the present invention. According to one aspect of the present invention, the seals are frits composed of copper glass. A suitable frit composition material is disclosed in U.S.

Patent Application No. 09/364,141 entitled "Fusion Sealed Article and Method" filed on July 30. 1999 which is incorporated by reference herein in its entirety. According to another aspect of the present invention, the frits are composed of low temperature glass such as, for example, SnO-Zn0-P₂θ₅ or PbO-SnO-P Oj glass with pyrophosphate filler as described in U.S. Patent No. 5.721,802 entitled "Optical Device and Fusion Seal^*' which is incorporated by reference herein in its entirety. Other pyrophosphate filled glass frits suitable for use with the present invention are described in U.S. Patent No.

5,926,599 entitled "Optical Device and Fusion Seal" which is incorporated by reference herein in its entirety. According to another aspect of the present invention, the seals are composed of gold-tin solder and the optical fiber is metalized with aluminum-gold- nickel or other suitable metal films prior to the placement of the solder. According to another aspect of the present invention, the seals may be composed of any low temperature sealing glass including, but not limited to lead silicates and lead borates.

In the embodiments of the present invention described below, one or more plugs are utilized with the packages of the present invention. According to one aspect of the present invention, the plugs are composed of epoxy. Suitable epoxies are described in greater detail in U.S. Patent No. 5,552,092 entitled "Waveguide Coupler" which is incorporated by reference herein in its entirety. According to another aspect of the invention, the plugs are composed of polymer or rubber.

Referring to the drawings, Fig. 1A shows a cross-sectional view of an athermalized hollow tube package 10 in accordance with the present invention. An optical fiber 12 is partially enclosed by a hollow tube 14 composed of β eucryptite, zirconium tungstate, phosphotungstate or some other suitable material with a negative coefficient of thermal expansion (CTE). Other suitable materials are disclosed in U.S.

Patent Application No. 60/086,053 entitled "Negative Thermal Expansion Materials

Including Methods of Preparation and Uses Therefor" which is incorporated by reference herein in its entirety. The hollow tube 14 has an inner diameter "a" (e.g., 255- 1000 μm), an outer diameter "b" (e.g., 3.0 mm) and a length "c" (e.g., 70 mm). The optical fiber 12 including its coating 16 has an outer diameter "d" (e.g., 250 μm). The coating 16 has been stripped from a length of optical fiber 12 which is contained within the hollow tube 14. The optical fiber 12 has written into it a short-period fiber grating

18 along a portion of the length which has been stripped of the coating 16. Two seals 20 disposed at each end 22 of the hollow tube 14 tensionally maintain and support the region of the optical fiber 12 containing the fiber grating 18. The seals 20 are frits composed of copper glass or another suitable material, as described above. The hollow tube package 10 also includes two plugs 24, composed of epoxy or another suitable material, as described above, disposed at each end 22 of the hollow tube 14. The ends 22 of the hollow tube 14 are funnel-shaped at an angle of 45° to facilitate placement of the plugs 24.

In order to compensate for the temperatures changes that the package 10 undergoes during testing and product life, the hollow tube 14 has a negative CTE, such as -80 x 10^"7 per C°. Thus, while the optical fiber 12 has a CTE of approximately 7 x 10^"7 per C°, the negative CTE of the hollow tube athermalizes the fiber grating 18, providing passive temperature compensation. Additionally, the hollow tube 14 protects the short period fiber grating 18 from external perturbations (such as mechanical stress) and environmental conditions (such as moisture). While presently preferred materials and dimensions are disclosed herein, one skilled in the art would appreciate that the hollow tube package 10 of the present invention may be composed of a variety of materials and sizes, and should not be construed as limited to the embodiments or dimensions shown and described herein which are exemplary.

Fig. IB shows a method 50 of forming the hollow tube package 10. In a first step 52, funnel-shaped ends (such as the funnel-shaped ends 22) are formed in a hollow tube (such as the hollow tube 14). To accomplish this, the hollow tube is mounted in a vertical orientation and nitrogen triflouride (NF ) gas is forced through a center bore of the hollow tube. The hollow tube 14 is then rotated, and an angled oxygen and gas torch burns the NF , forming the funnel-shaped end 22. The oxygen and hydrogen gas torch is mounted at a 45° angle with respect to an outer surface of the hollow tube. In a placement step 54, an optical fiber (such as the optical fiber 12) is placed within the hollow tube. During insertion, the coating of the optical fiber acts as a guide for the uncoated section of optical fiber containing the grating, preventing the uncoated section from contacting the inner wall of the hollow tube.

Next, in a tensioning step 56, the optical fiber is tensioned by a 5 gram weight. A vacuum is applied to the hollow center of tube in step 58, with a maximum vacuum of about 25 inches of H₂0. In a next fusing step 60, a seal (such as the frit seal 20 described above) is fused to each end by a laser system, ring burner or other heating system. Due to the heat sensitivity of the grating, the tube should be of sufficient length to assure that the grating is not affected by heat from the heating system. In step 62, the vacuum and tension are removed. In a tacking step 64, the ends of the hollow tube are tacked with plugs (such as the epoxy plugs described above). Each epoxy plug is applied manually into the ends with a small syringe and is then UV cured. Nominal post cure time is approximately 1.5 hr. at 125° C, or approximately 16 hr. at 90° C. The epoxy plugs also provide the additional benefit of spacing and preventing the optical fiber from making contact with the inside surface of the hollow tube, which would lower the strength of the optical fiber.

Another embodiment of the present invention is shown in Fig. 2A which depicts an athermalized shelf tube package 110. The shelf tube package 110 comprises an optical fiber 1 12 which is partially enclosed by a hollow tube 1 14 having openings 122 at each end. The hollow tube 1 14 is composed of a material such as β eucryptite, zirconium tungstate, or another material with a negative coefficient of thermal expansion (CTE) as described above. The tube 114 has an inner diameter (ID) (e.g., 255-1000 μm), an outer diameter (OD) (e.g., 3.0 mm), and a length (e.g., 70 mm). A minimum ID of 255 μm allows the use of optical fiber 112 which with its coating 116 has a combined diameter of 250 μm. As shown in Fig. 2A, the coating 116 has been removed from a length of optical fiber 1 12 which is contained within the tube 114.

The tube 114 includes first and second shelf sections 126, each shelf section 126 having a length (e.g., 1 1.0 mm). The optical fiber 1 12 has written into it a short period grating 118 along a portion of the length which has been stripped of the coating 1 16. A first seal 120 is fused to the optical fiber 1 12 and first shelf section 126. A second seal

120 is fused to the optical fiber 112 and second shelf section 126. Each seal 120 forms a hermetic seal in each opening 122. A carbon dioxide (CO₂) laser (or other heating method) is used to fuse the seals 120 in place. The seals are composed of copper glass or other suitable materials, as described above. A plug 124 is disposed on each shelf section 126, holding the optical fiber 1 12 in place and providing strain relief. The plugs 124 are composed of epoxy or other suitable materials, as described above.

In order to compensate for the temperatures changes that the package 110 undergoes during testing and product life, the hollow tube 114 has a negative CTE, such as -80 x 10^"7 per C°. Thus, while the optical fiber 1 12 has a CTE of approximately 7 x 10^"7 per C°, the negative CTE of the hollow tube athermalizes the fiber grating 1 18, providing passive temperature compensation. Additionally, the shelf tube package 1 10 protects the short period fiber grating 1 18 from external perturbations (such as mechanical stress) and environmental conditions (such as moisture). While presently preferred materials and dimensions are disclosed herein, one skilled in the art would appreciate that the shelf tube package 110 of the present invention may be composed of a variety of materials and sizes, and should not be construed as limited to the embodiments or dimensions shown and described herein.

Fig. 2B shows a method 150 of forming a shelf tube package in accordance with the present invention. In a first placement step 152, an optical fiber (such as the optical fiber 212) is placed within the hollow tube. During insertion, the coating acts as a guide and spacer for the uncoated section of optical fiber containing the grating, preventing contact with the tube.

Next, in a tensioning step 154, the optical fiber is tensioned by a 5 gram weight. A vacuum is applied to the hollow center of tube in step 156, with maximum vacuum of about 25 inches of H₂0. In a next fusing step 158, a seal (such as the frit seal 120) is fused to each opening (such as opening 122) by a heat source such as the laser system or ring burner described above. In a step 160, the vacuum and tension are removed. To provide strain relief, in a tacking step 150, a plug (such as the epoxy plug 124) is placed on each shelf section, holding the optical fiber in place. Each epoxy plug is applied manually into the ends with a small syringe and is then UV cured. Nominal post cure time is approximately 1.5 hr. at 125° C, or approximately 16 hr. at 90° C. The epoxy plugs also provide the additional benefit of spacing and preventing the optical fiber from making contact with the inside surface of the hollow tube, which would lower the strength of the optical fiber. Another alternative embodiment of the present invention is shown in Fig. 3 A, which depicts an athermalized two-piece package 210. The two-piece package 210 comprises a pair of housing members 214, shown in Figs. 3B and 3C, joined together along inner surfaces 215. Each housing member 214 is composed of a material such as β eucryptite, zirconium tungstate, or other materials with a negative CTE as described above. Each of the inner surfaces 215 of the members 214 includes a semi-circular longitudinal channel 217. Together, the two channels form the channel 217 which has a circular center hole 219 enclosing an optical fiber 212. Each of the inner surfaces 215 of the housing members 214 also includes four semi-circular transverse channels 221. The channels 221 form two circular seal holes 223 and two plug holes 225. An optical fiber 212 is partially enclosed by housing member 214. The optical fiber 212 includes a coating 216 which has been removed from a length of optical fiber 212 which is contained within the package 210. The optical fiber 212 has written into it a short- period grating 218 along a portion of the length which has been stripped of the coating 216. A seal 220 is disposed at each of the intersections of the center hole 219 and the seal holes 223. The seals 220 tensionally maintain and support the region of the optical fiber 212 containing the fiber grating 218. The seals are composed of copper glass or another suitable material, as described above. A plug 224 is disposed at each of the intersections of the center hole 219 and the plug holes 225. The plugs are composed of epoxy or another suitable material, as described above. The two housing members 214 are held together by the seals 220, or in an alternative embodiment, by an external clamp 227.

In order to compensate for the temperatures changes that the two-piece package 210 undergoes during testing and product life, the housing members 214 have a negative CTE, such as -80 x 10^"7 per C°. Thus, while the optical fiber 212 has a CTE of approximately 7 x 10^"7 per C°, the negative CTE of the hollow tube athermalizes the fiber grating 218, providing passive temperature compensation. Additionally, the two- piece package 210 protects the short period fiber grating 218 from external perturbations (such as mechanical stress) and environmental conditions (such as moisture). While presently preferred materials are disclosed herein, one skilled in the art would appreciate that the two-piece package 210 of the present invention may be composed of a variety of materials and sizes, and should not be construed as limited to the embodiments or dimensions shown and described herein.

Another alternative embodiment of the present invention is shown in Fig. 4A, which depicts an athermalized open channel package 310. An optical fiber 312 is partially contained in a longitudinal channel 317 of a bar 314 composed of a material such as β eucryptite, zirconium tungstate, or other materials with a negative CTE as described above. The optical fiber includes a coating 316 which has been stripped from a length of optical fiber adjacent to the channel 317. The bar 314 also includes two transverse channels 321. The optical fiber 312 has written into it a short-period fiber grating 318 along a portion of the length which has been stripped of the coating 316. A seal 320 is disposed at each of the intersections of the longitudinal channel 317 and the transverse channels 321. The seals 320 tensionally maintain and support the region of the optical fiber 312 containing the fiber grating 318. The seals are composed of copper glass or another suitable material, as described above. The open channel package 310 also includes two plugs 324. composed of epoxy or another suitable material, as described above, disposed at each end of the channel 317. The channels 317 and 321 provide improved mechanical locking of the seals 320 and plugs 324 to the bar 314. In order to compensate for the temperature changes that the package 310 undergoes during testing and product life, the bar 314 has a negative CTE, such as -80 x 10^"7 per C°. Thus, while the optical fiber 312 has a CTE of approximately 7 x 10^'7 per C°, the negative CTE of the hollow tube athermalizes the fiber grating 318, providing passive temperature compensation. Additionally, the open channel package 310 protects the short period fiber grating 318 from external perturbations (such as mechanical stress) and environmental conditions (such as moisture). While presently preferred materials are disclosed herein, one skilled in the art would appreciate that the open channel package 314 of the present invention may be composed of a variety of materials and sizes, and should not be construed as limited to the embodiments or dimensions shown and described herein. Fig. 4B shows a method 350 of forming an open channel package in accordance with the present invention. In a first placement step 352, an optical fiber (such as the optical fiber 312) is placed within a longitudinal channel of a bar (such as the bar 314). Next, in a tensioning step 354, the optical fiber is tensioned by a 5 gram weight. In a fusing step 356, a seal (such as the frit seal 320) is fused to each intersection of the transverse channels and longitudinal channel by a heat source such as the laser system or ring burner described above. In step 358, the tension is removed. To provide strain relief, in a tacking step 360, a plug (such as the epoxy plug 324) is placed on each end of the longitudinal channel, holding the optical fiber in place. Each epoxy plug is applied manually into the ends with a small syringe and is then UV cured. Nominal post cure time is 1.5 hr. at 125° C, or 16 hr. at 90° C.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the present invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

What is claimed is:

1. A temperature compensated optical waveguide device comprising: a tube having a first end and a second end and defining a cavity extending at least partially between said first end and said second end, said tube having a negative coefficient of thermal expansion; an optical fiber longitudinally disposed within said cavity and having a positive coefficient of thermal expansion; and a first seal and a second seal disposed with said cavity, such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

2. The temperature compensated optical waveguide device of claim 1 wherein the first and second seals are composed of solder; and an outer surface of the optical fiber and an inner surface of the tube both include a metalized layer.

3. The temperature compensated optical waveguide device of claim 1 further comprising: a fiber Bragg grating formed within the length of the optical fiber.

4. The temperature compensated optical waveguide device of claim 1 further comprising: a first epoxy plug disposed within the first end and a second epoxy plug disposed within the second end.

5. A method for forming a temperature compensated optical waveguide device comprising the steps of: providing a tube having a negative coefficient of thermal expansion and defining a cavity, said cavity having a first predetermined diameter; providing an optical fiber of a second predetermined diameter having a positive coefficient of thermal expansion, wherein said second predetermined diameter is less than said first predetermined diameter; inserting said optical fiber into said cavity; and forming a first seal and a second seal within said cavity, such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

6. The method of claim 5 further comprising, before the step of forming a first seal and a second seal, the step of: applying a vacuum to the cavity.

7. The method of claim 5 further comprising, before the step of forming a first seal and a second seal, the step of: tensioning the optical fiber.

8. A temperature compensated optical waveguide device comprising: a tube having a center section, a first shelf section, a second shelf section, a first end, and a second end, said center section defining a cavity extending at least partially between said first end and said second end, said tube having a negative coefficient of thermal expansion; an optical fiber longitudinally disposed within said cavity and adjacent to said first shelf section and said second shelf section; and a first seal and a second seal, said first seal fused to said optical fiber and said first shelf section at said first end, and said second seal fused to said optical fiber and second shelf section at said second end, such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

9. The temperature compensated optical waveguide device of claim 8 further comprising: a fiber Bragg grating formed within the length of the optical fiber.

10. The optical waveguide device of claim 8 wherein the first seal or the second seal include frits comprising low temperature glass.

11. The optical waveguide device of claim 10 wherein said low temperature glass includes copper glass.

12. The temperature compensated optical waveguide device of claim 10 wherein the low temperature glass includes pyrophosphate filled lead-tin phosphate glass.

13. The temperature compensated optical waveguide device of claim 8 wherein the first seal and second seal comprise solder.

14. The temperature compensated optical waveguide device of claim 13 wherein said solder comprises a creep resistant solder alloy of gold and tin.

15. The temperature compensated optical waveguide device of claim 8 further comprising: a first epoxy plug disposed on both the first shelf section and the optical fiber; and a second epoxy plug disposed on both the second shelf section and the optical fiber, such that the optical fiber is secured to both the first shelf section and the second shelf section.

16. A method for forming a temperature compensated optical waveguide device comprising the steps of: providing a tube having a center section, a first shelf section, a second shelf section, a first end, and a second end, said center section defining a cavity of a first predetermined diameter extending at least partially between said first end and said second end, said tube having a negative coefficient of thermal expansion; providing an optical fiber of a second predetermined diameter having a positive coefficient of thermal expansion, wherein said second predetermined diameter is less than said first predetermined diameter; inserting said optical fiber into said cavity such that said optical fiber is adjacent to said first shelf section and said second shelf section; tensioning said optical fiber; fusing a first frit to said optical fiber and said first shelf section at said first end to form a first seal; and fusing a second frit to said optical fiber and said second shelf section at said second end to form a second seal.

17. The method of claim 16 further comprising the steps of: depositing a first epoxy plug on both the first shelf section and the optical fiber, such that the optical fiber is secured to the first shelf section; and depositing a second epoxy plug on both the second shelf section and the optical fiber, such that the optical fiber is secured to the second shelf section.

18. A temperature compensated optical waveguide device comprising: a case having a first end and a second end, said case comprising a first housing member and a second housing member, said first member including a longitudinal channel and two transverse channels disposed on an inside face, said second member including a longitudinal channel and two transverse channels disposed on an inside face, wherein said inside face of said second member abuts said inside face said first member such said longitudinal channels define a longitudinal cavity extending between said first end and said second end, and said transverse channels define two transverse cavities extending into said case and intersecting said longitudinal cavity, said first housing member and said second housing member both having a negative coefficient of thermal expansion; an optical fiber longitudinally disposed within said longitudinal cavity having a positive coefficient of thermal expansion; and a first seal and a second seal disposed within said longitudinal cavity such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

19. The optical waveguide device of claim 18 wherein the first seal or the second seal include frits comprising low temperature glass.

20. The temperature compensated optical waveguide device of claim 19 wherein said low temperature glass includes copper glass.

21. The temperature compensated optical waveguide device of claim 19 wherein the low temperature glass includes pyrophosphate filled lead-tin phosphate glass.

22. The temperature compensated optical waveguide device of claim 18 wherein the first seal or second seal comprise solder.

23. The temperature compensted optical waveguide device of claim 22 wherein said solder comprises a creep resistant solder alloy of gold and tin.

24. The temperature compensated optical waveguide device of claim 18 wherein the first housing member further includes two additional transverse channels disposed on the inside face and the second housing member further includes two additional transverse channels disposed on the inside face such that said additional transverse channels define two additional transverse cavities extending into the case and intersecting the longitudinal cavity.

25. The temperature compensated optical waveguide device of claim 24 further comprising: a first epoxy plug disposed within the first end and a second epoxy plug disposed within the second end.

26. The temperature compensated optical waveguide device of claim 18 further comprising: a clamp securing the first housing member to the second housing member.

27. A temperature compensated optical waveguide device comprising: a member having a first end and a second end and defining a longitudinal channel extending at least partially between said first end and said second end, said member have a negative coefficient of thermal expansion; an optical fiber longitudinally disposed within said channel and having a positive coefficient of thermal expansion; and a first seal and a second seal disposed within said channel, such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

28. The temperature compensated optical waveguide device of claim 27 wherein the member further defines a first transverse channel and a second transverse channel.

29. The temperature compensated optical waveguide device of claim 28 wherein the first seal is disposed at the intersection of the longitudinal channel and the first transverse channel, and the second seal is disposed at the intersection of the longitudinal channel and the second transverse channel.

30. The temperature compensated optical waveguide device of claim 29 further comprising: a first epoxy plug disposed within the first end and a second epoxy plug disposed within the second end.

31. A method for forming a temperature compensated optical waveguide device comprising the steps of: providing a member having a negative coefficient of thermal expansion and defining a longitudinal channel, a first transverse channel, and a second transverse channel; providing an optical fiber having a positive coefficient of thermal expansion; placing said optical fiber into said longitudinal channel; tensioning said optical fiber; and forming a first seal and a second seal along said longitudinal channel, such that a length of said optical fiber is tensionally secured between said first seal and said second seal.

32. The method of claim 31 wherein the first seal is formed at the intersection of the longitudinal channel and the first transverse channel and the second seal is formed at the intersection of the longitudinal channel and the second transverse channel.

The method of claim 32 further comprising, before the step of forming a first seal and a second seal, the step of: tensioning the optical fiber.