Space mirror deformation: from thermo-mechanical measurements by speckle interferometry to optical comparison with...

Area of Science:

• Optical engineering
• Materials science
• Computational physics

Background:

• Space optics require rigorous experimental testing for performance validation.
• Increasingly stringent optical requirements make these tests expensive and time-consuming.
• A predictive modeling tool can mitigate these challenges.

Purpose of the Study:

• To develop and validate a multiphysics modeling approach for space optics.
• To predict the behavior of space optics under thermal loads.
• To compare experimental and simulation results for thermal deformation and wavefront error.

Main Methods:

• A multiphysics approach was employed to simulate optic behavior under thermal stress.
• Electronic speckle pattern interferometry (ESPI) measured local surface displacements.
• Rigid body motion was subtracted to determine surface deformation.
• Thermo-mechanical simulation results were validated against experimental data.

Main Results:

• Experimental surface deformations of a space mirror under thermal gradients were accurately predicted by the multiphysics model.
• The validated thermo-mechanical solution showed good agreement between experimental and numerical wavefront errors.
• The modeling tool offers a viable alternative to extensive physical testing.

Conclusions:

• The multiphysics modeling approach is effective for predicting space optic performance under thermal loads.
• This simulation tool can significantly reduce the cost and time associated with experimental testing.
• The validated model provides a reliable method for assessing optical performance in realistic conditions.