Optimization of depth of field and enhancement of viewing angle in three-dimensional light field fusion display system based on the design of aspherical symmetric compound lens

The three-dimensional (3D) light field fusion display system based on flat panel light field display (LFD) can effectively expand the depth of field (DOF) of the LFD. However, its viewing angle is narrow, which makes it difficult to reconstruct more comprehensive information of the 3D scene. In addition, the crosstalk caused by the aberration of the light control element used in the system causes aliasing in the images perceived by the viewer, reducing the quality of the 3D images. In order to achieve a high-quality 3D light field fusion display system with a large viewing angle and DOF, the calculation method of voxel size and the influence of aberration of light control element on DOF are analyzed in this paper. Based on the above analysis, the optical parameters and structure of the light control element have been redesigned, and the aspherical symmetric compound lens has been proposed and optimized for its optical characteristics using a reverse optical path scheme. A new generation of 3D light field fusion display system using optimized aspherical symmetric compound lens has been constructed and optical verification experiments have been conducted. The optical experimental results of the enlarged comparison image of the details and the comparison image of the entire viewpoint image show that the display effect of the system using optimized aspherical symmetric compound lens has improved significantly in terms of clarity and color performance compared to before. The viewing angle of the system has increased from 50° to 80°, which verifies the correctness and reliability of the DOF analysis method and the new structure of the light control element.