ABSTRACT
@#AIM:To investigate the accuracy, time-consuming and reliability of three Zernike algorithms in reconstruction of the corneal aberration in adaptive optics.<p>METHODS: Elevation data of corneal front surface collected on 20 normal eyes over a 6mm pupil were converted into the simulated original wave-front data by subtracting the best fitting sphere, which was then resampled at resolutions of 100, 300, and 500μm. Differences in elevation between adjacent pixels were used to generate simulated wave-front slope data, which were used to reconstruct wave-front by three algorithms: the regularized solution, the singular value decomposition, and Householder transform separately. The number of Zernike modes was from 1 to 130 separately in each reconstruction procedure. Each new wave-front map generated was directly compared to the originally sampled wave-front and the residual root-mean-square(RMS)error between the original and reconstructed map was recorded, also we investigate the time-consuming and reliability of the solution by calculating the condition numbers of the linear model and observing the mode coefficient matrix. <p>RESULTS: Householder transformation performed as well as the singular value decomposition by three sampling rates in reconstruction accuracy, while the regularized solution showed unacceptable results when the number Zernike modes used higher than 88 by the resolution was 500μm. With the modes number increased, the time that the singular value decomposition consumed increased more obviously than the time that the Householder transformation and the regularized solution consumed, and the difference between the latter two didn't show obviously. The higher the sampling rate was, also the lower the Zernike exponent number was, and the more reliable the result was, and the instability of regularized solution is more serious than the other two at the low sampling rate.<p>CONCLUSION:Householder transformation is superior the other two in accuracy as well as the highly effectiveness, and the reliability of three algorithms was almost identical at high sampling rate, while the Householder transformation still showed relatively stable performance at low sampling rate, which provides the reference and the theory basis of choice to the optimal algorithm which is applied in the adaptive optics system of real-time correction eyeball's aberration wave-front reconstruction.