problem. We also apply edge-based DFD display to DFD display using aerial image to solve the problem that the displayed image is difficult to see when observed from outside the viewing area. Edge-based DFD display does Abstract This paper proposed the aerial optical system of aerial image and rear display for edge-based depth-fused 3D (DFD) display to improve visibility of 2D image outside 3D viewing zone. Edge-based DFD display is composed of 2D image and its edge patterns. This leads to visibility improvement of 2D image outside 3D viewing zone, which is the problem of conventional DFD display. The proposed optical system can easily reconstruct a 3D image by changing luminance of edge patterns in front of or behind 2D image. We clarify that the proposed optical system is effective as a 3D display technology.