Further studies of the dynamic scattering mode in nematic liquid crystals

Heilmeier, George H.; Zanoni, Louis A.; Barton, L.

doi:10.1109/t-ed.1970.16918

Cited by 82 publications

(18 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reason could be that the reorientation of the LC molecules under the influence of the applied field was increased. V th is inversely proportional to the NLC Δε as shown in the following: [23,24] …”

Section: Liquid Crystalsmentioning

confidence: 99%

Reverse-mode polymer dispersed liquid crystal films prepared by patterned polymer walls

et al. 2015

View full text Add to dashboard Cite

This article proposes a methodology to prepare polymer dispersed liquid crystal (PDLC) films working in the reverse-mode operation, where the ion-doped nematic liquid crystals (NLCs) with negative dielectric anisotropy (Δε) were locked by polymer walls. On-state and off-state of films were controlled by an electric field. In the absence of an electric field, it appears to be transparent. In the field, the homogeneous alignment NLCs form dynamic scattering, giving rise to opaque. The effect of the cylindrical holes with different diameters of photo masks and liquid crystal Δε on the electro-optical properties and transmittance wavelength range of 400-3000 nm light of samples were investigated. It was found that it exhibited very good electro-optical characteristics, high contrast ratio and excellent infrared energy-efficient of films used as switchable windows.Keywords: reverse-mode polymer dispersed liquid crystal; polymer walls; nematic liquid crystal; negative dielectric anisotropy; electro-optical properties IntroductionPolymer dispersed liquid crystal (PDLC) films are technologically important class of materials that find numerous applications as electrically switchable optical devices.[1-3] PDLC films are formed by liquid crystal (LC) microdroplets embedded in a polymer matrix. They can exhibit either a droplet morphology in which droplets of LC are embedded in a polymer matrix, or a polymer ball morphology in which the LC takes up the voids and the crevices of a network structure formed by small polymer balls. In the normal-mode operation, they are in an opaque state (offstate) and can be turned into a transparent state (onstate) by controlling the LC molecule orientation by means of a suitable voltage. The reverse-mode PDLC films are transparent in its off-state and can be turned into an opaque on-state. A greater interest has been aroused by reverse-mode PDLC films that are useful as switchable windows, automotive applications [4,5] and used in a wide range of applications that need a transparent state in the absence of any applied voltage.Several authors have reported examples of reverse-mode PDLC films obtained by modification of the polymer surface energy,[6] by functionalising the LC/polymer matrix interface,[7] by using dualfrequency addressable LC,[8] by means of rough surfaces [9,10] or by increasing the LC content. [11]

show abstract

Section: Liquid Crystalsmentioning

confidence: 99%

Reverse-mode polymer dispersed liquid crystal films prepared by patterned polymer walls

et al. 2015

View full text Add to dashboard Cite

show abstract

“…However, this increase the current consumption and requires higher voltage drive electronics. The typical turn on times is -10-50 ms, while turn off time is -100-200 ms. To achieve the faster turn off (-5 ms), a dynamic scattering mode display is sometimes operated in fast turn off mode, i.e., after removal of the operating signal, a high frequency (more than the cutoff frequency) voltage signal is used [28,29,64,651. Both the rise and decay times of a homeotropic DSM cell are -5 times slower than those of a homogeneous display (all other factors such as the cell gap, LC mixture, etc., being the same) [29].…”

Section: Switching Timementioning

confidence: 99%

Nematic Liquid Crystals: Applications, Section 3.3

Bahadur¹,

Demus²,

Goodby

et al. 1998

Handbook of Liquid Crystals

View full text Add to dashboard Cite

“…In all of these applications it is clear that progress depends on recognizing basic mechanisms by which fields tend to induce instability and often turbulence. In liquids incentive also comes from the effect of instability on conduction in highly insulating [9] as well as relatively conducting [15,16] fluids, for permanent imaging in thermoplastics [5] and for dynamic imaging in liquid crystals [6,86].…”

Section: Bulk Interactionsmentioning

confidence: 99%

Electrohydrodynamics

Melcher¹

1973

Theoretical and Applied Mechanics

View full text Add to dashboard Cite

Further studies of the dynamic scattering mode in nematic liquid crystals

Cited by 82 publications

References 0 publications

Reverse-mode polymer dispersed liquid crystal films prepared by patterned polymer walls

Reverse-mode polymer dispersed liquid crystal films prepared by patterned polymer walls

Nematic Liquid Crystals: Applications, Section 3.3

Electrohydrodynamics

Contact Info

Product

Resources

About