Investigation of UR90 Outputting Annular Beam for a Chemical Oxygen Iodine Laser

摘要

In this paper, we mainly describe the structure of an unstable resonator with 90-deg beam rotation(UR90) outputting annular beam for a chemical oxygen iodine laser(COIL) and the geometry mode of the beam. A beam quality of 3.2 times diffraction limit was achieved in the experiment while the COIL average output power was approximately 4kw in the case of magnification of 1.69, as well as the property of the annular beam was analyzed.