Shack Hartmann Wavefront Sensor For The Human Eye Aberration Measurement

The optical performance of human eye has a directly impact on the daily lives of human beings, and it's significant to analyze the aberration of the human eyes. The measurement, based on the Shack-Hartmann sensing technology, obtaining the wave front aberration quickly and accurately, has been used for the detection of human eyes aberration in recent years. The core component of the Shack-Hartmann wavefront sensor is the lens array. Therefore how to reconstruct the wavefront quickly and accurately through the focal spots array which comes from the lens array focal plane, is the core issue of the Shack-Hartmann sensing technology. This paper concentrates on the study of the reconstruction of the human eyes wavefont. First of all, the basic principles of Shack-Hartmann sensor technology are introduced briefly. Then ,based on the shape characteristic of the wavefront of human eyes and the relationship between the parameters of lens array and the performance of the sensor, the parameters of lens array used for the measurment of the human eyes is designed. Furthermore, the wavefront reconstruction, including the detecion of the centroid of the spots array, the calculating the offset of the centroid, and fitting the wavefront with Zernike polynomial are studied. Finally, with the help of ZEMAX and MATLAB the wavefront of eyes as well as the lens array and the wavefront reconstruction are simulated respectively. Simulation results show that the reconstruction process of human eyes wavefront is basically consistent with the original wave-front generated by ZEMAX, and the recovery error is less than 10%.