Elliptically lensed polarisation maintaining fibres

Polarisation maintaining optical fibres have been directly lensed with spherical and elliptical lenses producing light modes with different ellipticities and semiaxes with the optical axes parallel to the polarisation axes. The specially adapted mode shapes and nearly Gaussian modes of these lensed fibres lead to coupling efficiencies of −2.6 dB from a 1.3 μm laser diode and of −1.1 dB from GaAs waveguides used in optoelectronic switches.