Distortion correction and image registration of ultralarge field of view near-eye display device.

A large field of view (FOV) is one dominant factor in improving the immersion of head-mounted displays (HMDs), and optical splicing is a mainstream solution to achieve it. For a display device with a large FOV, the camera may not be able to obtain the full-frame distorted image in a single shot. This paper proposes a computational correction method to achieve distortion correction for these devices. The method uses homography transformation to transform subsampled images to the same coordinate system for stitching, then performs the subregional Bézier patch fitting, which adequately describes the complex nonlinear distortion on the stitched image. Finally, the mapping table can be utilized for subsystem correction. Experiment results show that the method reduces the maximum standard deviation of the line fitting error from about 12 pixels to less than 1 pixel, effectively eliminating the distortion. For optical spliced HMDs, this paper proposes an image registration scheme that modifies the mapping table aforementioned by feedback adjustment to remove the misalignment of subsystem imaging results at the seam. Experiment results show that the method can ensure a good stitching effect.