Switchable focus using a polymeric lenticular microlens array and a polarization rotator

Optics Express (Impact Factor: 3.49). 04/2013; 21(7):7916-25. DOI: 10.1364/OE.21.007916
Source: PubMed


We demonstrate a flat polymeric lenticular microlens array using a mixture of rod-like diacrylate monomer and positive dielectric anisotropy nematic liquid crystal (LC). To create gradient refractive index profile in one microlens, we generate fringing fields from a planar top electrode and two striped bottom electrodes. After UV stabilization, the film is optically anisotropic and can stand alone. We then laminate this film on a 90° twisted-nematic LC cell, which works as a dynamic polarization rotator. The static polymeric lenticular lens exhibits focusing effect only to the extraordinary ray, but no optical effect to the ordinary ray. Such an integrated lens system offers several advantages, such as low voltage, fast response time, and temperature insensitivity, and can be used for switchable 2D/3D displays.

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Available from: Shin-Tson Wu, Oct 13, 2014
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    • "The LC device used here is a 90° twisted nematic (TN) cell[13]. TN is an electrically tunable achromatic half-wave (λ/2) plate and has been used as a polarization switch for adaptive lens[14,15]. For a linearly polarized input light, say p-wave, the output light can be converted to s-wave if the applied voltage is off (V = 0) or it remains p-wave if V>>V th (threshold voltage). "

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