Production of phase screens for simulation of atmospheric turbulence.

The ability to simulate atmospheric turbulence in the laboratory is a crucial part of testing and developing astronomical adaptive optics (AO) technology. We report on the development of a technique for creating phase plates that involves the strategic application of clear acrylic paint onto a transparent substrate. Results of interferometric characterization of these plates are described and compared to Kolmogorov statistics. The range of r(0) (Fried's parameter) achieved thus far is 0.2-1.2 mm, with a Kolmogorov power law. These phase plates have been successfully used by the Laboratory for Adaptive Optics at University of California, Santa Cruz in the Multi-Conjugate Adaptive Optics testbed as part of the Visible Light Laser Guidestar Experiments (Villages) calibration system and during integration and testing of the Gemini Planet Imager. Measurements of the turbulence from the plate in Villages are compared to the sky, which shows the plate produces good representative atmospheric aberrations. We are now distributing the plates to other members of the AO community.