Suppressing effects of micro-vibration for MTF measurement of high-resolution electro-optical satellite payload in an optical alignment ground facility

Abstract

Sensitivity to micro-vibration generated in an optical alignment ground facility increases with the optical aperture of the electro-optical payload mounted on the remote sensing satellite. The micro-vibration distorts the edge spread function (ESF) and changes the modulation transfer function (MTF) value during MTF measurements. Here, an ESF reconstruction network (ESFNet) is proposed to reconstruct the ESF distorted by micro-vibration. A proxy ground-truth ESF dataset for stable training of the proposed ESFNet via a supervised learning method is introduced. The proposed method is robust against both overfitting and underfitting for distorted parts of the ESF caused by micro-vibration. Experiments using ESF obtained in the facility with real micro-vibration show that the measurement error of MTF is around 0.02% when the ESFs are reconstructed using the proposed ESFNet.