25 CM BIMORPH MIRROR FOR PETAWATT LASER

摘要

The Central Laser Facility (CLF) at the Rutherford Appleton Laboratory has beeninvolved with the development of adaptive mirrors for more than ten years. During thistime we have developed bimorph adaptive mirrors of 150mm diameter, and a controlsystem operating at the few-Hz time scale for the correction of static and thermallyinduced aberrations in high-power laser chains. Such mirrors have played an importantrole in optimising the focusability of the petawatt beamline of the Vulcan laser. It wouldbe highly advantageous to apply adaptive control to the full 220mm diameter of theVulcan petawatt beam. As part of a LaserLab-funded European programme we aredeveloping large-aperture bimorph-type deformable mirrors, and have recentlyconstructed a prototype mirror of 250mm diameter. The key feature of this mirror is thatthe piezoceramic plate is monolithic, rather than segmented. This prototype mirror is, toour knowledge, the largest deformable mirror so far realized with bimorph technology.