Optical simulation of field-of-view distortion in see-through lightguide based on volume holographic optical elements

In this paper, we develop a precise simulation platform to investigate the effects of lightguide geometry when integrated with volume holographic optical elements (VHOEs). The simulation is based on practical optical parameters and physical configurations. Distortion in the viewed image along the horizontal field of view (HFOV) is attributed to inappropriate lightguide thickness; a thicker lightguide can result in a broken or discontinuous HFOV. Similarly, distortion in the vertical field of view (VFOV) arises from excessive lightguide length, leading to noticeable VFOV shrinkage. Furthermore, VFOV distortion may vary between the left and right sides of a single image due to differences in the effective propagation distance within the lightguide. The simulated distortions in both HFOV and VFOV show strong agreement with experimental results. In addition, all the lightguide effects are theoretically clarified. This detailed analysis offers valuable insights for optimizing lightguide design and contributes to the advancement of HUD and near-eye display technologies with see-through functionality.