The design and fabrication of birefringence lens array for integral imaging system with enhanced depth of field

An integral imaging (InIm) system enabling enhanced depth of field was proposed and demonstrated incorporating a pair of liquid crystal (LC) lens arrays (LAs), which exhibit two different refractive indexes depending on the light polarization. The proposed birefringence lens array (BLA) I and II were implemented by depositing a ZLI-4119 LC and an E-7 LC on top of a LA substrate in glass respectively. When the two BLAs were aligned appropriately, a birefringence was obtained for a specific light polarization in such a way the incoming light sees different refractive indexes for them. As a result, the focal length associated with the InIm system utilizing the BLAs was adaptively varied, thereby enhancing the depth of field for the image reconstruction. The proposed InIm system was simulated with the LightTools (R), proving that the focal length was adjusted with the help of the BLA. Finally the proposed InIm system successfully reconstructed the objects: The BLA employing the ZLI-4119 LC produced a real image with the focal length of 680 mm, while the other using the E-7 LC yielded a virtual image with the focal length of -29 mm.