Abstract 173

Submitted by Jean-christophe SINQUIN

Authors

J.-C. Sinquin, J.-M. Lurçon, C. Guillemard, P. Morin

Affiliations

CILAS

Abstract

1. Prototyping for small pitch concave or convex deformable mirrors. In the scope of feasibility study of two small pitch deformable mirrors with concave and convex surfaces for the E-ELT MCAO module, we have designed, manufactured and tested a 3.5 mm spacing, 28x28 order demonstrator . Its optical aperture is 100 mm diameter and shows a 270 mm concave curvature radius. We will present the results obtained with this demonstrator at ambient and at relatively low temperature (-40°C).

2. Experimental results obtained with 1-mm spacing deformable mirror. In the scope of demonstration, with the support of ESO and LAOG, we have developed a 1-mm spacing deformable mirror prototype with 50x50 actuators. This prototyping allows to validate the main important steps of manufacturing very high order deformable mirrors. These steps are machining and connecting processes. This new piezo array family called “miniDM” uses transverse piezo-electrical effect. We will present the first experimental results, which are mainly optical quality, maximum stroke and inter-actuator stroke.

3. Experimental results obtained with Tip/Tilt Mount for heavy SAM. A Tip/Tilt Mount prototype has been designed and manufactured for the Narrow Field Infrared Adaptive Optics System (NFIRAOS), which is the MCAO system of the TMT. This Tip/Tilt Mount, which comes from Observatoire de Paris concepts, will be used to correct tip/tilt jitter disturbances. These disturbances include atmospheric turbulence and telescope vibration effects caused by wind shake and mechanical vibration. The system shows an angular stroke of 500 µrad PV and a 90 Hz bandwidth (at -3dB in closed loop) while supporting a 32 kg deformable mirror. We will present the experimental results obtained with this prototype.