At-wavelength metrology of an X-ray mirror using a downstream wavefront modulator

Area of Science:

• X-ray optics and instrumentation
• Advanced metrology techniques
• Synchrotron radiation applications

Background:

• At-wavelength metrology is vital for evaluating X-ray optics under operational conditions.
• Wavefront random modulator techniques are increasingly used for in situ diagnostics.
• Accurately mapping wavefront slope to curved mirrors with downstream modulators is challenging.

Purpose of the Study:

• To develop a novel iterative method for accurate wavefront slope mapping.
• To overcome limitations in current at-wavelength metrology for curved X-ray mirrors.
• To improve the precision of in situ optical diagnostics.

Main Methods:

• Development of a new iterative algorithm for wavefront analysis.
• Utilizing a wavefront random modulator positioned downstream of the X-ray mirror.
• Comparison with conventional metrology approaches and offline optical measurements.

Main Results:

• The proposed iterative method significantly improves measurement accuracy.
• Results show strong agreement with offline optical metrology data.
• Demonstrated enhanced capability for mapping slope to curved mirror surfaces.

Conclusions:

• The developed iterative method enhances the accuracy of at-wavelength metrology.
• This advancement supports improved beamline operation and optics fabrication.
• The technique offers greater potential for real-time optical performance evaluation.