A display apparatus includes a coherent light source, a display unit, a light-diffusing element, and at least one optical element. The coherent light source is configured to provide coherent light beams. The display unit is configured to form a three-dimensional image beam based on interference of the coherent light beams, wherein the three-dimensional image beam is imaged on an intermediate imaging surface after passing through the display unit. The light-diffusing element is located on the intermediate imaging surface, wherein a diffusion angle of the three-dimensional image beam is sequentially changed by passing through the light-diffusing element. The at least one optical element is located on a transmission path of the three-dimensional image beam from the light-diffusing element, and is configured to project the three-dimensional image light beam passing through the display unit out of the display apparatus to display a three-dimensional image.