BEAM QUALITY ENHANCEMENT FOR A RADIOFREQUENCY EXCITED ANNULAR CO2-LASER

We report the preliminary experimental results obtained from an annula r radio-frequency excited CO2 laser with a Talbot cavity and a phase c orrecting mirror external to the cavity. The Talbot cavity is adopted in order to reduce the number of oscillating azimuthal modes. The use of the external profile-modulated mirror is aimed at reducing the beam phase modulation and thus increasing the amount of fundamental annula r mode energy content. The beam quality results to be sensibly increas ed. (C) 1998 American Institute of Physics. [S0003-6951(98)04344-7].