The adaptive secondary mirrors for the Large Binocular Telescope: a progress report

The two 911mm-diameter adaptive secondary (AS) mirrors for the Large Binocular telescope (LBT) are currently under manufacturing process. Each unit has 672 electro-magnetic force actuators. They control the figure of the Gregorian secondary 1.6mm-thick mirrors with an internal loop using the signal of co-located capacitive sensors. The obtained computational power of the on-board control electronics allows to use it as real-time computer for wavefront reconstruction. We present the progress in manufacturing and assembling of the first telescope unit, the progress in software production, the status of the testing facilities and an update on the latest modification of the design.

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