Speaker
Description
The “Absolute Multiline” has recently been tested on the Very Large Telescope (VLT) to monitor the Rigid Body Motion between its primary and secondary mirrors by forming an optical hexapod. This test is part of a more general evaluation of the adequacy, performance and robustness of such a measuring technique for monitoring the inter-mirror position of the future European Extremely Large Telescope (E-ELT). In this case, the “Absolute Multiline” may represent an asset, not only during the integration phase, but also to insure a proper collimation of the telescope to enter in the capture range of the star guiding sensors and finally to help identifying collimation degeneracy that cannot be captured by wavefront sensors. This presentation will cover the rationale, the experimental set-up and the results of the test performed on the VLT as well as future perspectives.
