Performance prediction of the AXAF Technology Mirror Assembly using measured mirror surface errors

Area of Science:

• Optical engineering
• Materials science

Background:

• Technology Mirror Assemblies (TMAs) are critical optical components.
• Accurate performance prediction is essential for TMA design and validation.
• Existing models may not cover the full range of surface features and environmental factors.

Purpose of the Study:

• To develop a comprehensive mathematical model for TMA performance prediction.
• To validate the model using new TMA data and X-ray test results.
• To identify factors influencing TMA performance, including surface characteristics and contamination.

Main Methods:

• Development of a scalar scattering model applicable to both large and small amplitude features.
• Incorporation of power spectral densities and autocovariance functions across spatial bandwidths.
• Analysis of TMA data from ~0.1-1000 mm(-1) spatial frequency range.
• Consideration of assembly, alignment, and particulate contamination effects.

Main Results:

• The developed model accurately relates measured TMA parameters to final performance.
• The model's predictions align with experimental X-ray test data.
• The study quantifies the impact of microroughness and broader spatial frequencies on performance.

Conclusions:

• The scalar scattering model provides a robust tool for TMA performance prediction.
• Understanding scattering properties and contamination is key to optimizing TMA performance.
• Repolishing is expected to significantly enhance TMA performance based on model insights.