Completion of VLT and GEMINI primary mirrors at REOSC

摘要

In 1989 and 1994, REOSC was awarded contracts for the optical fabrication of the four VLT and two Gemini 8-m class primary mirrors, respectively. We elaborate on the mirror concepts and their optical specifications, and discuss the fabrication and testing methods applied to the production of these mirrors. We also provide an overview of the facilities and equipment designed and built to transport, handle and process the mirrors. All units have been completed well within requirements; we provide detailed insight into the results obtained with all mirrors, and demonstrate that very large, aspheric mirrors can be produced to utmost accuracy ― in practice, well below the diffraction limit.