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Physics
Optics

Surface Slope Metrology on Deformable Soft X-ray Mirrors

Profile image of Sheng YuanSheng Yuan

2010, AIP Conference Proceedings

https://doi.org/10.1063/1.3463330
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4 pages

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Abstract

We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situ visible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

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References (9)

  1. P. Kirkpatrick and A. V. Baez, Formation of Optical Images by X-Rays, J. Opt. Soc. Am. 38 (9), 766-74 (1948).
  2. I. Ghozeil, Hartmann and other screen tests, in Optical Shop Testing, D. Malacara, ed. Wiley, New York, 1978, pp. 323-49.
  3. P. P. Naulleau, K. A. Goldberg and J. Bokor, Extreme ultraviolet carrier-frequency shearing Interferometry of a lithographic four-mirror optical system, J. of Vac. Sci. and Technol. B 18 (6), 2939-43 (2000).
  4. Sheng Yuan, Valeriy V. Yashchuk, Kenneth Goldberg, Richard S. Celestre, Matthew N. Church, Gregory Y. Morrison, Wayne R. McKinney, Tony Warwick, Thermal Effects on Kirkpatrick-Baez (KB) Systems of Bendable Mirrors, ALS Beamline Note, LSBL-961 (June 23rd, 2009).
  5. F. Siewert, V. V. Yashchuk, J. L. Kirschman, G. Y. Morrison, B. V. Smith, Initial Alignment and Commissioning of an Autocollimator Based Slope Measuring Profiler at the Advanced Light Source, LSBL Note LSBL-936 (January 9, 2009).
  6. V. V. Yashchuk, DLTP Performance Test with a 1280-m Spherical Reference Mirror, LSBL Note LSBL-931 (January 12, 2009).
  7. W. R. McKinney, S. C. Irick, J. L. Kirschman, A. A. MacDowell, T. Warwick, V. V. Yashchuk, New Procedure for the Adjustment of Elliptically Bent Mirrors with the Long Trace profiler, Proc. of SPIE 6704, 67040G (2007).
  8. W. R. McKinney, J. L. Kirschman, A. A. MacDowell, T. Warwick, V. V. Yashchuk, Optimal tuning and calibration of bendable mirrors with slope-measuring profiler , Opt. Eng. 48 (8), 083601-8 (2009).
  9. M. R. Howells, D. Cambie, R. M. Duarte, S. Irick, A. A. MacDowell, H. A. Padmore, T. R. Renner, S. Rah, R. Sandler, Theory and practice of elliptically bend x-ray mirrors, Opt. Eng. 39 (10), 2748-62 (2000).

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