DESIGN OF A NANOMETER-ACCURATE FORM MEASUREMENT MACHINE FOR SEGMENTED LARGE TELESCOPE MIRRORS

摘要

The planned extremely large telescope observatories with segmented giant primary mirrors will require metrology with nanometer accuracy. The two extremely large ground telescopes, the European Extremely Large Telescope (E-ELT [2]) and Thirty Meter Telescope (TMT [3]), feature telescopes with 39 meter and 30 meter primary mirrors (M1), respectively. The E-ELT consists of 798 hexagonal segments, while the TMT consists of 492 hexagonal segments. The segments of both telescopes are approximately 1.5 m from corner to corner.