The MEMS deformable mirror (DM) performances have been dramatically increased during the last years. Although
adaptive optics has the potential to address many optical problems faced by engineers and scientists, it has not yet
reached all domains of applications that it might reach. In this article, we present some key changes.
A new technology of deformable mirror will be presented. Based on magnetic actuators, these deformable mirrors feature record strokes (more than +/- 45μm of astigmatism and focus correction) with an optimized temporal behavior. Furthermore, the development has been made in order to have a large density of actuators within a small clear aperture (typically 52 actuators within a diameter of 9.0mm). We will present the key benefits of this technology for vision
science: simultaneous correction of low and high order aberrations, AO-SLO image without artifacts due to the membrane vibration, optimized control, etc.
Using recent papers published by Doble, Thibos and Miller, we show the performances that can be achieved by various configurations using statistical approach. The typical distribution of wavefront aberrations (both the low order aberration (LOA) and high order aberration (HOA)) have been computed and the correction applied by the mirror. We compare two configurations of deformable mirrors (52 and 97 actuators) and highlight the influence of the number of actuators on the fitting error, the photon noise error and the effective bandwidth of correction.
Membrane deformable mirrors based on magnetic actuators have been known for years. State-of-the-art deformable
mirrors usually have large strokes but low bandwidth. Furthermore, this bandwidth decreases with the diameter. In this
paper, we present the results of a new actuator principle based on magnetic forces allowing high bandwidth (up to a few
kHz), very large stroke (>30μm) with a record pitch of 1.5mm.
The benefits of this technology will be presented for three applications: astronomy, vision science and microscopy. The
parameters of the mirrors have been tuned such that the inter-actuator stroke of the deformable (more than 2.0μm) in
order to fit the atmosphere turbulence characteristics. In vision science, efforts have been made to correct both
simultaneously the low and high order aberrations (more than 45μm of wavefront correction on astigmatism and focus).
Finally, we will demonstrate how we have developed a deformable mirror able to correct spherical aberrations
The last part of the article is devoted to give some perspectives about this technology.
We present the improvement of science throughput of 1m class telescopes that can be obtained using COTS adaptive
optics. It is based on a new architecture of adaptive optics system using a new kind of magnetic deformable mirrors, a
highly sensitive EMCCD wavefront sensor and a novel real time architecture called ACE and working on a standard
It will be shown the dramatically increase of performances that can be achieved using small adaptive optics (typically
8x8 actuators) with 1m to 2m class telescopes and in particularly, we will focus our presentation of the improvement of
the science throughput thanks to this simple and efficient A.O. system
We describe the performances obtained with the latest developments of voice-coils deformable mirrors for the correction
of atmosphere turbulence. Thanks to the electro-magnetic principle of the deformable mirror, very large strokes are
obtained (more than 20μm) with a very large bandwidth (1 kHz). We further present the ALPAO Core Engine which is
an open and flexible environment allowing fast developments of high performances adaptive optics. We emphasize all
the benefits for free space optical communication.
Integrated optics technologies are an attractive alternative to classical bulk optics for the beam combination function of an interferometer. We propose a new integrated optics combiner for three apertures giving access to the closure phase on each output. It uses a multimode interference combination scheme realized by ion exchange on a glass substrate. This paper describes the theoretical behaviour of the beam combiner and its design constraints. Its interferometric behaviour is simulated and first experimental results using for the first time, as far as we know, a Near field Scanning Optical Measurement (NSOM) technique are discussed.
In order to observe smaller stellar objects, interferometric techniques are used. We propose a new recombiner for three telescopes realised by ion-exchanged on glass (K<sup>+</sup>/Na<sup>+</sup>) using a self-imaging multimode waveguide. The first part of this work consists of a theoretical study. We demonstrate that such a component is feasible even if the guided modes are weakly confined. To achieve this goal, we use three different modelling methods: Finite Difference Beam Propagation Method, Guided Modes Analysis and Radiated Modes Analysis. Each of these methods gives different information and permits to design a recombiner fulfilling the astronomical exigencies. The emphasis is put on excess losses, spatial filtering and polarization dependency. After this demonstration, results obtained with a first component used as a power splitter are presented. We conclude by presenting the remaining work.