Jong-Ho Hong

3D/2D convertible projection-type integral imaging using concave half mirror array

We propose a new method for implementing 3D/2D convertible feature in the projection-type integral imaging by using concave half mirror array. The concave half mirror array has the partially reflective characteristic to the incident light. And the reflected term is modulated by the concave mirror array structure, while the transmitted term is unaffected. With such unique characteristic, 3D/2D conversion or even the simultaneous display of 3D and 2D images is also possible. The prototype was fabricated by the aluminum coating and the polydimethylsiloxane molding process. We could experimentally verify the 3D/2D conversion and the display of 3D image on 2D background with the fabricated prototype.

Alignment layerless flexible liquid crystal display fabricated by an imprinting technique at ambient temperature

The authors report on an alignment layerless (AL) flexible liquid crystal (LC) display fabricated at ambient temperature through an imprinting process. One-dimensional microgrooves and two-dimensional arrays of microstructures embossed on plastic substrates provide the spontaneous alignment of the LC molecules and spacers for the uniform cell gap in a flexible LC display, respectively. It is found that the azimuthal anchoring energy, generated from the microgrooves, is on the order of 10−5J∕m2 which is strong enough to uniformly align the LC over large area. Our AL flexible LC display shows symmetric viewing characteristics and stable electro-optic properties under a bent environment.

Pixel-encapsulated flexible displays with a multifunctional elastomer substrate for self-aligning liquid crystals

We report on a pixel-encapsulated flexible liquid crystal display (LCD) based on an elastomer substrate of self-aligning LC molecules. The elastomer substrate, fabricated by a replica molding technique, has pixel-encapsulating walls that serve as spacers and allow for mechanical stability and reproducibility against bending deformations. Our pixel-encapsulated LCD provides great flexibility, durability, and excellent electro-optic performances in a highly bent environment.

Viewing Angle Switchable Liquid Crystal Display with Double Layers Separated by an Interlayer Support

We demonstrate a viewing angle switchable (VAS) liquid crystal display (LCD) with an interlayer support fabricated by imprinting lithography. The interlayer support is embedded in a single cell to separate two differently aligned LC layers, one of which is a primary layer for displaying images and the other is a complementary layer for switching viewing angles. Our VAS LC cell shows two viewing ranges that can be switched between ±40 and ±70°. Moreover, our method of using an interlayer support results in a reduction in the panel thickness and weight by 40% compared with the panel stacking method.

Fabrication of lateral and stacked color patterns through selective wettability for display applications

Abstract A simple and versatile method of fabricating color patterns in two‐dimension (2D) and three‐dimension (3D) was developed using the selective‐wettability approach. Red, green, and blue color elements are sequentially formed on a single substrate in a pattern‐by‐pattern and/or pattern‐on‐pattern fashion, through a simple coating process. Either 2D or 3D structures in an array format are produced by controlling the thickness of the hydrophobic layer (HL) coating a substrate within the framework of wetting transition. Moreover, it was demonstrated that the stacked geometry of two successive patterns can be easily tailored for various types of color arrays, with the pattern fidelity of a few tens of nanometers in terms of only a parameter of the HL thickness.

P-144: Single Mode Transflective Liquid Crystal Display with Dual Cell Gap Using a Multipurpose Substrate

We describe a single mode transflective liquid crystal display (LCD) having a multipurpose substrate in a dual cell gap configuration. The multipurpose substrate fabricated by a replica molding technique provides the vertical alignment for the liquid crystal molecules without any surface treatment and bi-level microstructures as spacers to maintain different cell gaps in two sub-pixels. The elastomeric multipurpose substrate is thinner and lighert than a typical glass substrate. Our transflective LCD shows no electro-optical disparity between the transmissive part and the reflective part as well as enhanced portability due to reduction over 30 % in thickness and weight.

Adhesive-Transfer Bonding Technique for Flexible Liquid Crystal Displays with High Mechanical Stability

We report on an adhesive-transfer bonding technique for improving mechanical stability of a flexible liquid crystal display (LCD) with an elastomer substrate. Permanent adhesion between an elastomer substrate and a plastic substrate is generated through thermal cross-linking of a curing agent prepared on the elastomer substrate by precise stamping. Our flexible LCD assembled using the adhesive-transfer bonding technique is found to show excellent mechanical stability in a highly bent environment.

Fabrication of a Dual-Gap Substrate Using the Replica-molding Technique for Transflective Liquid Crystal Displays

Abstract A replica‐molding method of fabricating a dual‐gap substrate for transflective liquid crystal (LC) displays is demonstrated. The dual‐gap substrate provides homeotropic alignment for the LC molecules without any surface treatment and embedded bilevel microstructure on one of the two surfaces to maintain different cell gaps between the transmissive and reflective subpixels. The proposed transflective LC cell shows no electro‐optic disparity between two subpixels and reduces the panel thickness and weight by 30% compared to the conventional transflective LC cell, which has two glass substrates.

An integrated elastomer substrate with a lens array and pixel elements for three-dimensional liquid crystal displays

In this paper, a concept of an integrated elastomer substrate for a three-dimensional (3D) liquid crystal display based on the integral-imaging method is presented. The elemental lens array and columnar spacers were integrated into one of the two substrates, an elastomer substrate, through an imprinting process. The integrated elastomer substrate was capable of maintaining the uniform liquid crystal (LC) cell gap and promoting homeotropic LC alignment without any surface treatment. The monolithic approach reported herein will provide a key component for 3D displays with enhanced portability through a more than 40% weight reduction compared with the conventional integral-imaging method.

Unitary Transflective Liquid Crystal Display with an In-Cell Retarder on a Wire Grid Plate as a Reflector–Polarizer in a Single Driving Configuration

A unitary type of a transflective liquid crystal display (LCD), having the same optical efficiency in both the transmissive (T) part and the reflective (R) part, is developed using an in-cell patterned (IP) retarder fabricated directly on a wire grid (WG) plate in a twisted-nematic geometry. The WG plate is used for a substrate and served as a polarizer in the T region and a reflector in the R region. In this unitary transflective LCD, it was found that the high optical efficiency and the fast response are easily achieved in a single driving scheme since the electro-optical disparity between the transmittance and the reflectance is intrinsically eliminated.