Claims
- 1. A focusing lensed fiber, comprising:
an optical fiber terminated with a lens, the lens having a distance to beam waist greater than Rayleigh range.
- 2. The focusing lensed fiber of claim 1, wherein the lens has a f-number greater than one.
- 3. The focusing lensed fiber of claim 1, wherein the distance to beam waist is greater than 100 μm
- 4. The focusing lensed fiber of claim 1, wherein the lens comprises silica.
- 5. The focusing lensed fiber of claim 1, wherein the lens comprises doped silica.
- 6. The focusing lensed fiber of claim 1, wherein a diameter of the lens is larger than a diameter of the optical fiber.
- 7. The focusing lensed fiber of claim 1, wherein a diameter of the lens is smaller than a diameter of the optical fiber.
- 8. The focusing lensed fiber of claim 1, wherein a diameter of the lens is the same as the diameter of the optical fiber.
- 9. The focusing lensed fiber of claim 1, wherein the lens has a back-reflection greater than −55 dB.
- 10. The focusing lensed fiber of claim 9, wherein a surface of the lens is coated with an anti-reflection coating.
- 11. A method for forming a lensed fiber, comprising:
resistibly heating a selected region of a glass fiber for a predetermined time; and pulling on the glass fiber while resistibly heating to form a convex surface at the selected region.
- 12. The method of claim 11, wherein the glass fiber is a coreless fiber.
- 13. The method of claim 12, further comprising splicing an optical fiber to the glass fiber.
- 14. The method of claim 13, wherein pulling on the glass fiber comprises pulling on the glass fiber in a direction away from a splice formed between the glass fiber and the optical fiber.
- 15. The method of claim 11, wherein the glass fiber is a single-mode fiber and the convex surface is formed at a tip of the glass fiber.
- 16. The method of claim 11, wherein the glass fiber is a multimode fiber and the convex surface is formed at a tip of the glass fiber.
- 17. The method of claim 11, wherein the glass fiber is a polarization-maintaining fiber and the convex surface is formed at a tip of the glass fiber.
- 18. The method of claim 11, further comprising enlarging a radius of curvature of the convex surface by resistively heating the convex surface.
- 19. The method of claim 18, wherein resistively heating the convex surface comprises moving a resistive heat source in a direction toward the convex surface as the radius of curvature of the convex surface is enlarged.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Application Serial No. 60/298,841, entitled “Thermally Formed Lensed Fibers for Imaging and Condenser Applications,” filed Jun. 15, 2001, of Ukrainczyk et al., and No. 60/352,753, entitled Thermally Formed Lensed Fibers, filed Jan. 28, 2002, of Ukrainczyk et al.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60298841 |
Jun 2001 |
US |
|
60352753 |
Jan 2002 |
US |