Abstract
Purpose: :
Peripheral vision and off axis aberration not only play an important role in daily visual tasks but may also influence eye growth and refractive development. Measuring the off-axis optical quality of the eye with a Hartmann Shack wavefront sensor requires methods for reconstructing wavefront from the gradient data defined within an elliptical domain.
Methods: :
In addition to two published reconstruction methods (Atchison et al, JOSA 19(11) 2180; Lundström et al, J Biomed Opt 10(3) 034002) based on least-squares fitting of wavefront slope to spatial derivatives of Zernike polynomials, two new methods (inscribed methods and boundary methods) based on the Fourier integral theorem were derived rigorously and implemented in Matlab.
Results: :
Wavefronts obtained from a wide angle schematic eye via ray tracing in Zemax were used as test cases to validate the theoretical predictions of the four methods. The RMS of reconstruction error was less than 1% of RMS of the tested wavefront for all four methods.
Conclusions: :
The four proposed methods based on least-squares fitting and Fourier integration were successfully implemented in Matlab to solve the general wavefront reconstruction problem from the gradients data defined over an elliptical pupil. The validation of the four methods on wavefronts obtained from a wide angle schematic eye indicates their numerical stability during objective Hartmann Shack Wavefront Sensor measurements of human eye.