Low Cell Gap Polymeric Liquid Crystal Lens for 2-D/3-D Switchable Auto-Stereoscopic Display

We propose a planar polymeric liquid crystal (LC) lens with a low cell gap (~ 4.6 μm) for a 2-D/3-D switchable auto-stereoscopic display. The proposed lens consists of two LC layers, one is a photopolymerized LC lens layer with a non-uniform refractive index with parabolic curve distribution, and the other is a half-wave LC switching layer of the vertical alignment type, which performs the 2-D/3-D image switching. The optimized refractive index of the LC lens layer was simply realized by polymerizing the LC molecules using a reactive mesogen. The proposed LC lens allow fast 2-D/3-D switching with low voltage and a simple fabrication process because of a low cell gap of the switching layer. We verified the electro-optical characteristics of the proposed LC lens by fabricating each layer after optimizing the cell structure. The measured focal length as a function of the applied voltage in the 3-D mode was compared with the calculated focal length and we confirmed that the measured results agreed with the calculated results.