Leon Wilhelmus Godefridus Stofmeel

Novel concept for full‐color electronic paper

— Despite a steep increase in commercial devices comprising paper-like displays, a much desired feature is still missing: bright full-color electronic paper. A new reflective-display technology has been developed to solve this issue. For the first time, the principles behind this in-plane electrophoretic technology will be presented, which enables the realization of full-color reflective displays with a higher brightness than presently available e-paper technologies, without compromising paper-like properties such as viewing angle and ultra-low power consumption. An additional major advantage (e.g., for future low-cost manufacturing) is that, besides direct-drive and active-matrix configurations, a passive-matrix option with analog gray levels has been successfully developed.

Optical performance of in-plane electrophoretic color e-paper

— Several e-paper technologies are currently under development with the ultimate goal of replacing printed ink on paper. Here, optical performance measurements on monochrome in-plane electrophoretic e-paper devices with unsurpassed brightness, contrast, and viewing-angle performance are reported. The measurement results are captured in a straightforward optical model that allows extrapolation to full-color performance. It demonstrates that in-plane electrophoretic color e-paper technology has the unique potential to deliver on the high standards required by digital-signage applications.

LP-11: Late-News Poster: Novel Transflective LCD with Ultra-wide Viewing Angle

A novel transflective LCD with ultra-wide viewing angle has been developed. This display contains an in-cell patterned retarder with two different values of the birefringence in each pixel, which replaces the conventional external retarders. As a result this display is brighter, thinner and has lower power consumption and wider viewing angle than conventional transflective LCDs.

46.1: Invited Paper: Novel Design for Full‐Color Electronic Paper

Despite a steep increase in commercial devices comprising paper-like displays, a much desired feature is still missing: bright full-color electronic paper. We have developed a new reflective display technology to solve this issue. for the first time we will report about the principles behind our in-plane electrophoretic technology, which enables the realization of full-color reflective displays with a higher brightness than all present e-paper technologies, without compromising paper-like properties like viewing angle and ultra-low power consumption. An additional major advantage (e.g. for future low-cost manufacturing) is that, besides direct-drive and active-matrix configurations, a passive-matrix option has been developed successfully.

Technologies towards patterned optical foils applied to transflective LCDs

— For better front-of-screen performance for transflective LCDs, a technology with extra free optimization parameters for the optical stack is needed. Thin wet coatable retarders which enable adjustment of the optical activity on the (sub)pixel level have been developed. Isotropic domains have been created in nematic retardation films by thermal patterning or photopatterning. Employing such a patterned retarder in a transflective LCD leads to an LCD that is lighter and thinner with good reflectivity, high transmission, and low chromaticity at all gray levels and wide viewing angles. The patterned thin-film technology has been proven to be versatile and applicable in various LCD designs.

Bright e-skin technology and applications: Simplified gray-scale e-paper

Abstract— Bright-color electronic-paper technology based on in-plane electrophoresis is very suitable for application in non-emissive digital surfaces, such as electronic skins, eco-skins, and electronic wallpaper for atmosphere creation. Aimed at these applications, simplified electrode geometries, aperiodic cell geometries, and a novel concept for built-in gray levels have been developed.

Next‐generation mobile LCDs with in‐cell retarders

In-cell retarders can be a major breakthrough for mobile LCDs. When a patterned in-cell retarder replaces the external retarders on transflective LCDs, brighter and thinner transflective LCDs with lower power consumption and wider viewing angle can be obtained. Additionally, when in-cell retarders are applied in reflective LCDs, the thickness of the LCD is considerably reduced without affecting the optical performance of the reflective LCD. This paper presents the technology needed to make in-cell retarders and the performance of reflective and transflective LCDs with in-cell retarders.