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Aplanatic corrector designs for the extremely large telescope
G Moretto1, T A Sebring, F B Ray
1Soar Telescope Project, National Optical Astronomy Observatories, Tucson, Arizona 85719, USA. Moretto@uswest.net
Applied Optics
|March 18, 2008
Summary
Future extremely large telescopes may use economical spherical primary mirrors. New all-reflecting corrector designs can overcome spherical aberration and coma, enabling fast optical performance for advanced astronomical observations.
Area of Science:
- Astronomy and Astrophysics
- Optical Engineering
Background:
- The development of extremely large telescopes (30-50 m class) is a key goal for 21st-century astronomy.
- Fixed spherical reflectors offer an economical and manufacturable approach for constructing large primary mirrors.
Purpose of the Study:
- To investigate catoptric (all-reflecting) corrector designs for telescopes utilizing spherical primary mirrors.
- To address the challenges of spherical aberration and coma inherent in large spherical optics.
Main Methods:
- Exploration of various all-reflecting optical configurations.
- Analysis of corrector designs to mitigate aberrations in spherical mirror systems.
Main Results:
- Demonstration of several viable catoptric corrector designs.
- Enabling the use of fast optical systems with large spherical primary mirrors.
Conclusions:
- Catoptric correctors can effectively compensate for aberrations in spherical primary mirrors.
- This approach facilitates the construction of next-generation extremely large telescopes with improved optical performance.
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