A light field image can achieve a realistic visualization of a complex scene because it contains directional information and intensity information of light; however, its advantages cannot be fully realized due to the limited angular range of a light field camera. For this reason, we processed a light field focal stack with a masked back projection algorithm to reconstruct the panoramic light field sub-aperture image and thereby achieved the goal of expanding the angular field of view of the light field. The method described in this paper consists of two main parts: focal stack stitching and panoramic light field reconstruction. To stitch a focal stack, two depth cues were fused to extract high-precision index maps for generating high-quality all-in-focus images and for calculating the transformation relationship between light fields. To generate a panoramic light field, we use a masked back projection algorithm to process the panoramic focal stack and to reconstruct a sharp panoramic light field sub-aperture-images. Finally, we demonstrate the generation of high-quality, all-in-focus images and sharp panoramic light-field sub-aperture-images with no loss of the field of view.