Systems

Multi conjugate adaptive optics (MCAO)

MCAO

The fundamental limitation of classical adaptive optics (AO) methods like SCAO is the narrow field of view. To overcome this problem the concept of AO requires further development. The technique called multi conjugate adaptive optics (MCAO) utilizes more than one deformable mirror (DM) in the process of correcting the wavefront aberrations. Each mirror is optically conjugated to an individual distance from the telescope and corrects the aberrations produced by different layers of atmosphere.

The signals driving the deformable mirrors are obtained from severals wavefront sensors (WFSs), each observing its own guide stars. This information is processed to first reconstruct the 3D structure of the atmospheric turbulence profile and then estimate the shapes of the DMs. The crucial first step of solving the 3D profile is called atmospheric tomography and the related mathematical problem is severely ill-posed. In order to overcome the negative effects of the ill-posedness, sophisticated methods from the field of inverse problems, such as regularization, have to be applied.

→ Read more about the developed reconstruction methods:

• 3-step approach
• FEWHA