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Updated: Jun 27, 2026
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Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
The misalignment induced aberrations of TMA telescopes
Kevin P Thompson1, Tobias Schmid, Jannick P Rolland
1Optical Research Associates, 3280 E. Foothill Blvd, Suite 300, Pasadena, California 91107, USA. kevin@opticalres.com
Optics Express
|December 10, 2008
Summary
The James Webb Space Telescope
Area of Science:
- Optical Engineering
- Astronomy
- Astrophysics
Background:
- The James Webb Space Telescope (JWST) utilizes a three-mirror anastigmat (TMA) design.
- Performance of TMA telescopes is significantly impacted by third-order misalignment aberrations within the operational field of view.
Purpose of the Study:
- To identify and characterize the dominant third-order misalignment aberrations in TMA telescopes.
- To introduce a novel aberration dependent on field and image orientation.
Main Methods:
- Analysis of third-order aberrations in TMA optical systems.
- Application of nodal aberration theory to derive new aberration terms.
Main Results:
- Two primary third-order misalignment aberrations affect TMA telescopes.
- A field-constant third-order coma, similar to that in Ritchey Chretien telescopes.
- A new field-asymmetric, field-linear third-order astigmatism, dependent on image orientation.
Conclusions:
- The identified aberrations are critical for understanding and correcting image quality in TMA telescopes like JWST.
- Nodal aberration theory provides a powerful framework for analyzing complex optical systems and discovering new aberration behaviors.
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