ann20032 — Mededeling
Design achievements for actuators and sensors of the main mirror of ESO's ELT
24 november 2020: M1, the main mirror of ESO’s Extremely Large Telescope (ELT), is moving closer to completion with the approval of the final design for its edge sensors, with its positions actuators also nearing this key milestone. The sensors and actuators are crucial to the optical quality and functionality of the giant 39-metre mirror. The ELT is planned to start operating later this decade in the Chilean Atacama Desert. The primary mirror on the ELT, M1, is composed of 798 hexagonal segments, made of a thin glass-ceramic material. To ensure the optical quality of the mirror, its segments have to work together to maintain the mirror’s shape, despite changes in the telescope's position and in external conditions, such as temperature, pressure and wind. Movable supports and sensors for the mirror, namely the M1 position actuators and edge sensors, allow each mirror segment to move independently and with nanometric (1 millionth of a ...