Optical interferometry, especially the lateral Shearing interferometer, has long played a
role in wavefront sensing. Phase-Shifting Interferometry and also Self-Referencing
Interferometry have significant advantages over the Shack-Hartmann wavefront sensor.
Phase difference between two interfering beams is determined by measuring the intensity
while the phase difference between the two interfering beams is changed in a known
manner three times. The phase difference can then be determined in the presence of
aberration. Adaptive wavelets will be applied to Phase-Shifting Interferometry in order
to address both noise and coherence and increase the depth of fringes. Phase is
determined by means of wavelet ridge extraction which will increase the depth of
interference fringes and improve resolution.
We present human eye wavefront generator (HEWG) introduced inside aberrometer for dynamic reproduction of human
eye aberrations. It's main element is bimorph deformable mirror and a telescope. Deformable mirror generates human
eye aberrations in real time. We have recorded aberrations time traces for plurality of subjects using aberrometer and
reproduced them with the help of the generator at 10Hz frequency, that is inherit to human eye aberrations dynamics.
Experimental results indicate that HEWG can reproduce dynamics of human eye aberrations with residual error less than
λ/10 microns. Such a model can be useful for testing, for example, customized contact lenses or wavefront guided
The problem of correct measurement of human eye aberrations is very important with the rising widespread of a surgical procedure for reducing refractive error in the eye, so called, LASIK (laser-assisted in situ keratomileusis). In this paper we show capabilities to measure aberrations by means of the aberrometer built in our lab together with Active Optics Ltd. We discuss the calibration of the aberrometer and show invalidity to use for the ophthalmic calibration purposes the analytical equation based on thin lens formula. We show that proper analytical equation suitable for calibration should have dependence on the square of the distance increment and we illustrate this both by experiment and by Zemax Ray tracing modeling. Also the error caused by inhomogeneous intensity distribution of the beam imaged onto the aberrometer's Shack-Hartmann sensor is discussed.