Nonlinear spline wavefront reconstruction through moment-based Shack-Hartmann sensor measurements

Area of Science:

• Optical Engineering
• Wavefront Sensing and Adaptive Optics

Background:

• Aberration reconstruction is crucial for optical system performance.
• Existing methods like the first moment method (SABRE) have limitations in accuracy and efficiency.

Purpose of the Study:

• To introduce a novel spline-based aberration reconstruction method using moment measurements (SABRE-M).
• To evaluate the performance of SABRE-M against existing methods, particularly for higher-order aberrations and in low-light conditions.

Main Methods:

• Utilizes first and second moment information from Shack-Hartmann (SH) sensor focal spots.
• Employs bivariate simplex B-spline basis functions for wavefront reconstruction.
• Compares SABRE-M with SABRE using numerical experiments across various aberration orders and SH array sizes.

Main Results:

• SABRE-M demonstrates superior performance compared to SABRE, especially for higher-order aberrations.
• Achieves comparable accuracy to SABRE with a halved sampling grid (reduced subapertures).
• Enables the use of larger lenses, advantageous for low-light applications.

Conclusions:

• SABRE-M offers a more accurate and efficient approach to wavefront aberration reconstruction.
• The method's ability to use fewer subapertures enhances its applicability in challenging optical environments.
• This advancement holds significant potential for improving imaging in low-light conditions.