ASTRONOMICAL IMAGING: New adaptive optics system at Lick Observatory uses MEMS

摘要

Adaptive optics systems with MEMS deformable mirrors enable large ground-based telescopes to achieve diffraction-limited images by correcting for the light-distorting effects of Earth's atmosphere. Astronomers have a limitation when using telescopes on Earth: The air turbulence distorts and blurs the incoming light. Spaceborne telescopes overcome this limitation, but they are limited in terms of the collecting aperture by the size, weight, and cost considerations associated with launching to space. The largest space observatory, the Hubble Space Telescope, has a 2.6-m-diameter primary mirror, which is relatively small compared to the several ground-based observatories with 8- and 10-m-aperture telescopes, and the 30-40 m telescopes currently being planned. Almost all the big ground-based observatories today use adaptive optics systems and instruments dedicated to high-resolution science imaging. Adaptive optics is a means of correcting for the atmospheric turbulence during an exposure, enabling astronomers to take advantage of the diffraction-limited resolution of the large aperture.