<title>HPDLC color reflective displays</title>

Abstract

We have carried out experiments and simulations to optimize the materials and processes for fabricating holographically formed polymer dispersed liquid crystal (HPDLC) devices. Bright reflective HPDLC displays with peak reflection above 60% have been achieved with fast, sub-millisecond tON + tOFF switching speed. The switching voltage has been reduced by more than a factor of 2 by selecting appropriate liquid crystal and polymer materials and by the addition of surfactants. The viewing angle of HPDLCs has been extended by a novel fabrication technique. We have fabricated color HPDLC demonstration displays by stacking red, green, and blue HPDLC layers and have achieved the widest color gamut that has ever been reported for a reflective display. The methods for making these novel color reflective displays and the measured are presented.

Tunable polymer/liquid crystal composite devices

“…This result agrees with the previous report by Yuan et al. 55 It is worth mentioning that, besides adding surfactant, a high dielectric anisotropy material can also be added into the LCpolymer composite to reduce the driving voltage. 93 Another interesting thing to note is that, in Figure 4.16(b), an optical bounce is clearly observed immediately after the electric field is applied.…”

“…The combination with holography makes holographic polymer dispersed liquid crystal (H-PDLC) more useful in optical communications, 124 , 125 information storage, 60 integrated optics and flat panel displays. 55,126 The most interesting thing in PDLCs and H-PDLCs is that liquid In this experiment, the materials used to fabricate the fly's-eye lens were TMPTA, NVP, RB, and NPG. The ratio of TMPTA/NVP/NPG/RB was 62/25/2/1 by weight.…”

49.3: H‐PDLC Color Separation Device for Image Capture Systems

“…We have developed methods for effective tuning of the central wavelength and spectral bandwidth of the HPDLC structures. 2,5 We have pioneered new approaches for enhancing the viewing cone of HPDLCs 5 , stacking multi-film HPDLCs for dramatically increased bandwidth and photopic efficiency, 6 and reducing HPDLC operating voltages. 5 All of these features of HPDLC technology contribute to their unique appeal as color separation devices for image capture.…”

Holographic Polymer‐Dispersed Liquid Crystals: Materials, Formation, and Applications

“…In the following parts of this review article, we will concentrate on the H-PDLCs. H-PDLCs have wide range applications for displays [35], switchable gratings [14,[36][37][38], photonic crystals [39][40][41], lasers [42][43][44][45], microlenses [46,47], and so forth. A vitally important method used to construct H-PDLC devices is photopolymerization induced phase separation (PIPS) by either UV or visible lasers, depending on the materials used.…”

“…After the removal of the external electric field, the nematic director configurations gradually revert to the original status due to the elastic torque, where the optical bounce would be difficult to be observed at the edge of "off " state. For acrylate-based H-PDLCs, reported values of τ on vary from 25 μs [107] to 750 μs [35] and the reported τ off values are slightly longer, ranging from 44 [107,108] to 1000 μs [109]. For the thoil-ene-based H-PDLCs, the reported values of τ on vary from 550 μs to 6.7 ms and the reported τ off values vary from 1.2 milliseconds to 2.2 milliseconds [48,110,111], which are generally much longer than those of the acrylatebased H-PDLCs.…”