Active Optics: Vase or Meniscus Multimode Mirrors and Degenerated Monomode Configurations

Multimode deformable mirrors allow to superpose optics aberration modes up to high orders. The elasticity analysis leads to consider mainly Clebsch-Zernike modes that belong to a sub-class of optics modes. Theoretical results and associated geometries are also derived for some single modes. This allows discovering degenerated configurations using a minimal set of applied external forces. We present interferometric results from active optics experiments including the degenerated configurations for third-order astigmatism and fifth-order triangle modes.