Microlens array calibration method for a light field camera

This paper presents a methodology and mathematical foundation for the calibration of the microlens array position used in light field cameras. The accurate estimation of optical system parameters is crucial for performing a 4D light field reconstruction based on 2D camera intensity images. The method presented in this paper allows the calculation of four distinct parameters which characterize the microlens array position: microlens pitch, rotational offset and translational offsets in two directions. All of the parameters are calculated with relation to the image sensor of a camera. The calibration procedure involves capturing a single image of an evenly illuminated, plain white surface. The center point of each lenslet is assessed using a center-of-gravity method, and the obtained coordinates are then used to calculate the parameter values as a solution for non-linear optimization problems in least squares sense.