Reflective optics for irradiance redistribution of laser beams: design

The output irradiance of a typical unstable resonator with circular symmetry has a central obscuration and is peaked near the obscuration. A method is presented for designing two-mirror optical systems to convert this beam into a beam of arbitrary obscuration ratio and more uniform irradiance. A method is also given for analyzing the alignment sensitivity of such a system. An example shows that useful irradiance redistributions can be achieved with alignment sensitivities comparable to ordinary Cassegrain systems.