Multi-aperture imaging with Fermat spiral sub-aperture arrangement

Area of Science:

• Optical Engineering
• Telescope Design
• Image Processing

Background:

• Multi-aperture optical telescopes offer high resolution, low cost, and light weight.
• Future telescopes will utilize numerous segmented lenses, necessitating optimized sub-aperture arrangements.
• Conventional hexagonal and ring arrays face limitations in performance.

Purpose of the Study:

• To introduce and evaluate the Fermat spiral array (FSA) as a novel sub-aperture arrangement for multi-aperture imaging systems.
• To compare the imaging performance of FSA against conventional arrays using point spread function (PSF) and modulation transfer function (MTF).
• To assess the impact of FSA on overall image quality metrics like PSNR and SSIM.

Main Methods:

• Simulated and experimental analysis of PSF and MTF for FSA and conventional arrays.
• Development of a new MTF evaluation function for mid-frequency performance.
• Comparative imaging simulations and experiments to measure PSNR and SSIM.

Main Results:

• FSA reduces PSF sidelobe intensity by an average of 12.8 dB (simulation) and 4.45 dB (experiment) compared to conventional arrays.
• FSA improves the system's MTF and mitigates image ringing effects.
• Imaging simulations and experiments show superior image quality with FSA, evidenced by higher PSNR and SSIM.

Conclusions:

• The Fermat spiral array (FSA) offers enhanced imaging performance for multi-aperture systems.
• FSA effectively suppresses sidelobe intensity and improves modulation transfer function.
• This novel arrangement is a promising solution for next-generation optical telescopes.