The direct pickup of integral imaging typically needs to overcome the limitation on the restricted depth of field under a lenslet array. We use the portable commercial Lytro standard camera as the integral imaging system and optically display these 4D light field data by the proposed parallax boosting algorithms with enhancing parallax. Using depth slicing, retargeting and parallax boosting, the depth of the integral imaging display is presented in a uniform compression with the same proportion as the real scene. The simulation results show the feasibility of the proposed method and provide an efficient way for the acquisition of elemental image array.
A method aiming at depth of field of light field based Fresnel hologram is proposed, which is generated by using the weighted type smart pixel mapping. The conventional integral holograms are generally generated through Fourier transforming the elemental images (EI) of II into hogels. However, the non-uniform compression along optical axial is inevitable within the generation of integral hologram. The weighted type smart pixel mapping is introduced to enhance the depth of field of light field-based Fresnel hologram while keeping a compact image size and being free from moving the lenslet array. The processed hologram can reconstruct the 3D image with the combined light fields of all the integral hologram sequences. Finally, the experiment of real 3D object is numerically and optically conducted. The high matching results among them confirm this work a better performance over the conventional methods.
In order to optically refocus three-dimensional (3-D) objects on their real depths, we design an adaptive periodic δ-function array (A-PDFA)-based 3-D optical refocusing method. An A-PDFA kernel with adaptively determined impulse number is first generated, and next by convolving this A-PDFA with the elemental image array (EIA) captured using an integral imaging system, the depth-filtered EIA is obtained to finally refocus the objects on their real depths. Based on simulations and experiments, the performance of the A-PDFA-based 3-D optical refocusing method is confirmed with the widest effective process zone and the highest image quality compared to other classical 3-D optical refocusing methods. Thus, it is believed the proposed method potentially can be used in various 3-D imaging and display applications.