A bistable flexible electronic display has been developed based on photographic technology, processes, and materials. Using photographic film coating techniques, an aqueous cholesteric liquid crystal dispersion, a dielectric layer, and a dark layer were deposited onto patterned transparent conductors on a polymeric web. Second conductors were printed over the active display layers to complete display manufacture in a roll‐to‐roll process. Simple seven‐segment displays and matrix displays have been generated using these techniques. The displays can use contact electronics to eliminate drive cost from the displays. Several prototype applications were demonstrated. Displays produced with these processes were low‐cost, thin, flexible, passively driven, and retained an image without an applied electric field.

We use the Jones matrix method to develop a numerical method which can be used to calculate the reflection of cholesteric liquid crystals. We derive the formula for the propagation of normally incident light in a cholesteric liquid crystal with multiple reflections taken into account. Using the derived formula, we numerically calculate the reflection spectra of the cholesteric liquid crystal under various conditions, and compare them with the results obtained using the Berreman 4 × 4 method.

We report on a monitor‐sized, thin, dimensionally and thermally stable mini‐LED backlight enabled by a patterned glass diffuser (PGD). Our backlight has a luminance of between 0.9 × and 1.05 × compared to a reference mini‐LED backlight using a thick diffuser plate, while providing a better local dimming control and comparable zone and panel luminance uniformity and color uniformity. The PGD technology can reduce the number of LEDs.

To understand the mechanism behind the pitch change during the transient planar to the planar state transition of a cholesteric liquid crystal ͑while it is relaxing from the homeotropic state to the planar state͒, we studied a more controlled situation of pitch change in a thermochromic liquid crystal. We studied the pitch change in the liquid crystal, as a function of temperature, under various surface alignment conditions such as homogeneous and homeotropic surface alignments. In a cell with homogeneous surface treatment, the liquid crystal showed a discontinuous pitch change, while the pitch change was rather continuous in a cell with homeotropic treatment. The numerical simulations also showed an existence of continuous pitch change in a homeotropic cell, but not in a homogeneous one. This led to a prediction that when a cholesteric material is switched from the homeotropic state to the planar state, the transition may be much faster for the homeotropically treated cell as compared to the homogeneously treated cell. We performed experiments to verify this prediction with a chiral nematic mixture. Indeed, the homeotropic to planar state transition time of a homeotropic cell was 5 msec, much faster compared to about 200 msec for corresponding transition in a homogeneous cell.

Design rules for wire grid polarizers, used as polarizing beamsplitters and reflective polarizers for polarization recycling, are found to be different. Wire grid polarizers with low fill factors of ~0.18-0.25 are found to be more efficient in polarization recycling than regular polarizers with fill factors of ~0.4-0.6.

We have investigated a new design for a turning film used in combination with wedge‐shaped light guide plates. The selected design has a top periodic lenticular structure that is in registration with the bottom periodic prisms. Relative registration shift in the prisms and the top lenticular structure was found to be beneficial. Use of such turning film drastically enhances the on‐axis brightness.

High pretilt angle can help stabilizing the desired bend configuration of π‐cells but also changes the electro‐optical behaviors. We report here a study on how the pretilt angle affects the electro‐optical properties of π‐cells, including the critical voltages needed to stabilize the bend configuration, the minimum voltages needed to turn the π‐cells fully on, the cell gap required to produce the desired π phase retardation, the transmittance‐voltage curves, the response time, and the viewing angle characteristics. The results provide a guidance to construct π‐cells with various pretilt angles.

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