Mirror Coating at the Large Synoptic Survey Telescope

Made-to-order stripping and vacuum coating solutions for special applications are realized by Von Ardenne (VA), the global leader in vacuum technology from Germany. For the Large Synoptic Survey Telescope (LSST), a project funded by the National Science Foundation and Department of Energy, VA is developing the washing and coating plant to ensure best quality of the three large telescope mirrors. The LSST, located on the Cerro Pachón ridge in Chile, has the ability to survey the entire sky in only three nights to address the most pressing questions in astronomy and physics.

Approximately every two years, the three mirrors are transferred from the telescope to the stripping station and then carefully vacuum coated. With a seven-year production time for the 8.4m primary mirror and Chile being a country with high seismic activity, the safety of the mirrors, plant, and workers is of major importance. This unique safety challenge is considered and reflected in VA´s design of the individual components.

This presentation will give an insight into the current status of work, the design and challenges of the washing station, the restrictions on site, and new findings into the vacuum coating process for the LSST.