Design and validation of a scanning Shack Hartmann aberrometer for measurements of the eye over a wide field of view.
Peripheral vision and off-axis aberrations not only play an important role in daily visual tasks but may also influence eye growth and refractive development. Thus it is important to measure off-axis wavefront aberrations of human eyes objectively. To achieve efficient measurement, we incorporated a double-pass scanning system with a Shack Hartmann wavefront sensor (SHWS) to develop a scanning Shack Hartmann aberrometer (SSHA). The prototype SSHA successfully measured the off-axis wavefront aberrations over +/- 15 degree visual field within 7 seconds. In two validation experiments with a wide angle model eye, it measured change in defocus aberration accurately (<0.02microm, 4mm pupil) and precisely (<0.03microm, 4mm pupil). A preliminary experiment with a human subject suggests its feasibility in clinical applications.
Wei
Xin
X
School of Optometry, Indiana University, Bloomington, Indiana 47405, USA. weix@indiana.edu
Thibos
Larry
L
D057128:Aberrometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007909:Lenses; D012030:Refractive Errors / Q000175:diagnosis* / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity