Wavefront detection and reconstruction method for the active optical system of a large FOV space camera based on a...

Area of Science:

• Optical Engineering
• Remote Sensing Technology
• Space Optics

Background:

• Space cameras face optical aberrations due to the space environment, degrading imaging quality and remote-sensing data value.
• Existing reference light sources (RLS) are insufficient for real-time aberration compensation in large field-of-view (FOV) pushbroom imaging space cameras (PISC).

Purpose of the Study:

• To propose and validate a novel method for wavefront detection and reconstruction in PISCs.
• To enhance imaging quality and the value of remote-sensing data through real-time aberration correction.

Main Methods:

• A planar sampling mirror array was designed and implemented within the secondary mirror aperture plane of the PISC.
• Numerical calculations and simulation analysis were performed using a near-realistic distorted optical system as a benchmark.
• Wavefront aberrations were detected and reconstructed using the proposed mirror array method.

Main Results:

• The root-mean-square (RMS) value of fitting residuals between the wavefront and primary mirror shape was less than λ/100 across all FOVs.
• Experimental results closely matched simulation and theoretical predictions.
• The fitted surface residual RMS achieved was 8.7 nm.

Conclusions:

• The proposed planar sampling mirror array method effectively enables real-time wavefront detection and reconstruction for PISCs.
• This active optical technology significantly improves optical system performance, ensuring high imaging quality and enhancing remote-sensing data.
• The method addresses the limitations of existing RLS and meets engineering requirements for advanced space imaging.