Two-step process for micro-lens-fibre fabrication using a continuous CO2 laser source

Hemispherical micro-lenses have been fabricated using a single-mode optical fibre end. The process consists of a new two-step fabrication using only a continuous CO2 laser source. In the first step, the fibre is heated with the laser and stretched until it splits, resulting in two symmetrical tapers. In the second step, the micro-lens is formed by melting the rotating fibre tip. Parameters of heating and stretching are optimized to ensure reproducibility. Characterizations have been performed and confirm the assumed Gaussian beam profile. We performed the focal length and beam waist measurements and compared them with theoretical approximations. We showed the flexibility of the fabrication process and the interest of micro-lenses in several applications.

[1]  A F Benner,et al.  Laser micromachining of efficient fiber microlenses. , 1990, Applied optics.

[2]  Hans W. P. Koops,et al.  Fabrication of a refractive microlens integrated onto the monomode fiber , 1996 .

[3]  James A. Harrington,et al.  Sculpted optical silica fiber tips for use in Nd:YAG contact tip laser surgery: part 1--fabrication techniques , 1992 .

[4]  Daisuke Kato,et al.  Light coupling from a stripe‐geometry GaAs diode laser into an optical fiber with spherical end , 1973 .

[5]  Mohamed Ketata,et al.  Microlens fibers fabricated by a melting-tapering process using a CO2 laser , 1999, Other Conferences.

[6]  Julius Dipl.-Ing. Wittmann,et al.  Experimental investigation of the beam spot size radius in single-mode fibre tapers , 1984 .

[7]  Timothy A. Birks,et al.  Control of optical fibre taper shape , 1991 .

[8]  P. Bear,et al.  Microlenses for coupling single-mode fibers to single-mode thin-film waveguides. , 1980, Applied optics.

[9]  Julius Dipl.-Ing. Wittmann,et al.  Fabrication and Investigation of Drawn Fiber Tapers with Spherical Microlenses , 1985 .

[10]  L. Cohen,et al.  Microlenses for coupling junction lasers to optical fibers. , 1974, Applied optics.

[11]  C. Pannell,et al.  Heat transfer modelling in CO2 laser processing of optical fibres , 1998 .

[12]  H. Presby,et al.  Near 100% efficient fibre microlenses , 1992 .

[13]  M. Spajer,et al.  A scanning local probe profilometer and reflectometer: application to optical control of integrated circuits , 1994 .

[14]  C W Barnard,et al.  Single-mode fiber microlens with controllable spot size. , 1991, Applied optics.

[15]  F S Barnes,et al.  Microlenses on the end of single-mode optical fibers for laser applications. , 1985, Applied optics.

[16]  H. Kuwahara,et al.  Efficient coupling from semiconductor lasers into single-mode fibers with tapered hemispherical ends. , 1980, Applied optics.

[17]  H Ghafoori-Shiraz,et al.  Microlens for coupling a semiconductor laser to a single-mode fiber. , 1986, Optics letters.

[18]  T. Birks,et al.  Shape of fiber tapers , 1992 .

[19]  G. Eisenstein,et al.  Chemically etched conical microlenses for coupling single-mode lasers into single-mode fibers. , 1982, Applied optics.

[20]  C. Vieu,et al.  Fabrication and characterization of optical-fiber nanoprobes for scanning near-field optical microscopy. , 1998, Applied optics.