Phase effects owing to multilayer coatings in a two-mirror extreme-ultraviolet Schwarzschild objective
- Center for X-Ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
The aberrations of a multilayer-coated reflective Schwarzchild objective, which are influenced both by mirror surface profiles and by multilayer coatings, are evaluated with a phase-shifting point diffraction interferometer operating in the extreme ultraviolet. Using wave-front measurements at multiple wavelengths near 13.4 nm, we observed chromatic aberrations and wavelength-dependent transmission changes that were due to molybdenum{endash}silicon multilayer coatings. The effects of chromatic vignetting due to limited multilayer reflection passbands on the imaging performance of the Schwarzchild optic are considered. The coating characteristics extracted from the interferometry data on the two-mirror optical system are compared with previously reported coating properties measured on individual mirror substrates. {copyright} 1998 Optical Society of America
- OSTI ID:
- 306241
- Journal Information:
- Applied Optics, Journal Name: Applied Optics Journal Issue: 34 Vol. 37; ISSN APOPAI; ISSN 0003-6935
- Country of Publication:
- United States
- Language:
- English
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