04/16/02
Hamdani Slim Observatoire de la Cote d'Azur
2130 route de l'Observatoire SF2A- PNPS- PNP- ASHRA-
06460 Caussols, France
Presentation 1 : None
First tests for a low cost curvature oriented AO (ASHRA)
Slim Hamdani, Alain Blazit
Since a few years we are developing a low cost adaptive optics device for the GI2T optical interferometer. Our AO is based on a curvature sensor and a 31 actuators bimorphe mirror. Our design of the wave front sensor use an array of prisms that split the intra-extra focal plane and focus them directly on avalanche photo diodes (APD). This configuration reduce the cost and allow an easy and fast alignment. We present here the design and the results obtained on a test bench for the whole loop. Our home made APD follow the 2.5 kHz modulation of the intra-extra focal plane and their alignment through a pierced copper block is well stable. The calculator follow the wave variations with a cut-off frequency of 250 Hz. We are know considering the integration of this AO on the recombination table of the GI2T interferometer.