A study of Wavefront Aberration Measurement Technology based on Centroid Calculation

The basic structure of the Shack-Hartmann wavefront sensor (SHWFS) is a microlens array and a set of sensors. Some conditions before the light enters the sensor from the imaging system cause the pixels to sense uneven light and generate a lot of noise in the image. Therefore, a set of noise filtering methods is needed to reduce the influence of noise in the image. Theoretically, the strongest point of the laser spot can be regarded as the center of mass of the laser spot. In this study, the best focus is used to capture the image. Perform image processing and use the program to evaluate various weights and thresholds to obtain centroid coordinates. The centroid control group will be used as an unaffected standard reference in the future. After that, the system adds an experimental group that changes the light wave front to perform quality control. The calculation of the wavefront value obtained by evaluating the position of the light spot, Zernike coefficient and Zemax can be used to verify the accuracy of the calculated wavefront aberration.