Shaping the intensity profile of a laser beam is desired by various industrial applications. In this paper, a new approach is presented to design and fabricate liquid crystal (LC) micro‐optical elements (MOEs) with engineered Pancharatnam–Berry (PB) phases for beam shaping. By generalizing the Snell's law for spatially variant PB phases, molecular orientation patterns are designed for the liquid crystal MOEs to shape a Gaussian laser beam into flattop intensity profiles with circular and square cross‐sections, with the β parameter varied from 4 to 42. It is demonstrated that such liquid crystal beam shaping MOEs can be fabricated with high throughput and high resolution by using a photopatterning technique based on plasmonic metamasks and that they produce excellent beam quality, no zero‐order light leakage with a beam size from 10 to 600 µm. As the plasmonic metamasks allow for encoding arbitrary molecular orientations, i.e., arbitrary geometric phase profiles, the approaches presented here are widely applicable to large‐scale manufacturing of liquid crystal MOEs for any beam shapes.

In this work, we took a closer look at transmissive polarization volume holograms (T-PVH) to provide clarifications on their geometry, physics, and optical responses by finite-difference time-domain (FDTD) simulation and experimental validation. First, we introduced the four possible geometries of T-PVH and simulated their optical responses in terms of diffraction efficiency, polarization selectivity, and polarization output. It is shown that the configuration we called “Slanted T-PVH ( B - θ / D - θ + 90 ),” where the director is perpendicular to the Bragg planes, has the advantageous property of maintaining circular output polarization states. For this configuration, a detailed simulation of spectral, angular, and polarization responses was completed. Finally, we validated the FDTD simulation results of the Slanted T-PVH ( B - θ / D - θ + 90 ) structures with experiments.

In this work, we focus on the polarization state management in optical devices using optical elements based on circular polarization. As an example, we point out the issue in a waveguide display using circular polarization optical elements as input/output couplers, where the polarization state of the light can change as it propagates in the waveguide due to total internal reflection (TIR). This has a negative effect on the waveguide output coupler efficiency, image uniformity, and the polarization multiplexing capability. To address this problem, we discussed two different methods to compensate the polarization state change. With the compensator applied to correct the polarization state change in the waveguide, the optical elements based on circular polarization can be used with their advantages as input/output couplers for waveguide displays.

In this work, we focus on the polarization state input, propagation and output of waveguide display device using polarization volume holographic gratings (PVH) as couplers. First, a detailed study of the transmissive PVH (T‐PVH) is presented in terms of diffraction efficiency, polarization selectivity and polarization output, which is expected to be used as the waveguide input/output couplers. The configuration here called “Slanted T‐PVH” has the advantageous property of maintaining orthogonal circular output polarization states. Then, the polarization state management of light propagating in waveguide is considered. The issue that the polarization state of the light can change as it propagates in the waveguide due to total internal reflection (TIR) is made clear, that has a negative effect on the waveguide PVH input/output couplers efficiency, image uniformity, and the polarization multiplexing capability. Finally, it is shown that applying compensators to correct the polarization state change can solve the polarization state change in a waveguide.

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