## 4 3D Integral Imaging Display Experimental Results
In contrast, Figure 7b presents the elemental image array after applying the depth rescaling process, where the depth range of the real 3D scene has been rescaled from 425 mm to 100 mm. By integrating both depth rescaling and scene resizing, the resulting elemental image array is depicted in Figure 7c. In this case, the depth range of the 3D scene is scaled from 425 mm to 100 mm along the z axis, while the scene size is adjusted on the x-y axis with a resizing factor of 0.35. Note that due to the use of multiple reference planes that better match the object's depth during the depth rescaling process (as discussed in Section 2), details in globe are well preserved in the elemental images, as shown in Figure 7c. In contrast, with the conventional SPOC method, which uses a single reference plane, details in the globe are lost, as illustrated in Figure 7a, because the reference plane is far from the actual object depth. In the experiment, a smart phone monitor and a lenslet array were used for the InIm 3D display system, as shown in Figure 8 The gap (_g_) between the display device and the lenslet array is equal to the focal length (_f_) of each optical lenslet. The display device is set in the center of the reconstruction space; therefore, the real image floating outside of the display plane and the virtual image converging inside of the display plane will be visualized synchronously for 3D display. Due to light diffraction and pixelated imaging device, the depth range of this display system is around 80 mm to 100 mm, centering at the display plane. Parameters of the display system for the experiment are listed in Table 4.  
Figure 6: A real 3D scene captured using synthetic aperture integral imaging technique. (**a**) Two samples of elemental images; (**b**) the corresponding estimated depth maps. The 3D display results of the computationally generated 3D scene are shown in Figure 9. Figure 9 presents three display results for the computer-generated 3D scene. \begin{table}
\begin{tabular}{c c} \hline \hline
**Description** & **Parameters** \\ \hline Display device & Smart phone monitor \\ Size of display panel & 102 mm (H) \(\times\) 57 mm (V) \\ Resolution of display device & 1920 (H) \(\times\) 1080 (V) \\ Pixel size of display device & Approx. 53 \(\upmu\)m \\ Total number of elemental images (EIs) & 96 (H) \(\times\) 54 (V) \\ Pixel number on each EI & 20 (H) \(\times\) 20 (V) \\ Pitch of lenslet array & 1 mm \\ Focal length of a lenslet & 3.3 mm \\ Field-of-view & 17.23 degree \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Specifications of integral imaging 3D display. Figure 8: Experimental setup for the observation of the integral imaging 3D display. Figure 7: Synthetically generated elemental image arrays for 3D display: (**a**) Using the conventional SPOC method, preserving a large depth range of 435 mm. (**b**) Depth range rescaled to 100 mm; however, the field-of-view exceeds the capacity of the device. (**c**) Depth range rescaled to 100 mm along the z axis, with the field-of-view resized on the x-y axis by a factor of 0.35. From left to right, the images represent (i) the display result with the original object parameters, where depth range remains 300 mm without scene resizing; (ii) the display result after rescaling the depth from 300 mm to 80 mm along the z-axis, without scene resizing; and (iii) the display result after combing depth rescaling (form 300 mm to 80 mm along the z-axis) with field-of-view resizing on the x-y axis using a factor of 0.5. Figure 9b displays the five different viewpoint results from various perspectives of the computer-generated 3D scene. The 3D display results of the real 3D scene are shown in Figure 10. Figure 10a presents the three display results for the real large-depth 3D scene.