P.1:Distinguished Student Poster Paper: Submillisecond-response Polymer Network Liquid Crystal Cylindrical Microlens Array for 3D Displays

The methods to enhance contrast ratios (CRs) in scattering-type transflective liquid crystal displays (ST-TRLCDs) based on polymer-network liquid crystal (PNLC) cells are investigated. Two configurations of ST-TRLCDs are studied and are compared with the common ST-TRLCDs. According to the comparisons, CRs are effectively enhanced by assembling a linear polarizer at the suitable position to achieve better dark states in the transmissive and reflective modes of the reported ST-TRLCDs with the optimized configuration, and its main trade-off is the loss of brightness in the reflective modes. The PNLC cell, which works as an electrically switchable polarizer herein, can be a PN-90° twisted nematic LC (PN-90° TNLC) cell or a homogeneous PNLC (H-PNLC) cell. The optoelectric properties of PN-90° TNLC and those of H-PNLC cells are compared in detail, and the results determine that the ST-TRLCD with the optimized configuration using an H-PNLC cell can achieve the highest CR. Moreover, no quarter-wave plate is used in the ST-TRLCD with the optimized configuration, so a parallax problem caused by QWPs can be solved. Other methods for enhancing the CRs of the ST-TRLCDs are also discussed.

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Sourcing and Qualifying Passive Polarised 3D TVs

Electronic Imaging ◽

10.2352/issn.2470-1173.2021.2.sda-100 ◽

2021 ◽

Vol 2021 (2) ◽

pp. 100-1-100-6

Author(s):

Andrew J. Woods

Keyword(s):

Liquid Crystal ◽

3D Display ◽

Consumer Market ◽

Testing Technique ◽

Stereoscopic 3D ◽

Wide Range ◽

3D Displays ◽

Liquid Crystal Shutter ◽

Rear Projection

Millions of Stereoscopic 3D capable TVs were sold into the consumer market from 2007 through to 2016. A wide range of display technologies were supported including rear-projection DLP, Plasma, LCD and OLED. Some displays supported the Active 3D method using liquid-crystal shutter glasses, and some displays supported the Passive 3D method using circularly polarised 3D glasses. Displays supporting Full-HD and Ultra-HD (4K) resolution were available in sizes ranging from 32" to 86" diagonal. Unfortunately display manufacturers eventually changed their focus to promoting other display technologies and 2016 was the last year that new 3D TVs were made for the consumer market. Fortunately, there are still millions of 3D displays available through the secondhand- market, however it can be difficult to know which displays have 3D display support. This paper will provide a listing of specifically Passive 3D TVs manufactured by LG, however it has been our experience that the 3D quality varied considerably from one display to another hence it is necessary to qualify the quality of the 3D available on these displays using a testing technique that will be described in the paper.

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Fabrication of a Liquid Crystal Microlens Array Film with Oligothiophene-Doped Polymerizable Liquid Crystals

Molecular Crystals and Liquid Crystals ◽

10.1080/15421400903054394 ◽

2009 ◽

Vol 511 (1) ◽

pp. 298/[1768]-308/[1778]

Author(s):

Motoi Kinoshita ◽

Tomohiro Kobayashi ◽

Atsushi Shishido ◽

Tomiki Ikeda

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Microlens Array

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Polymer network as a template for control of photoconductivity of a liquid crystal semiconductor

Liquid Crystals ◽

10.1080/02678290412331282082 ◽

2004 ◽

Vol 31 (9) ◽

pp. 1265-1270 ◽

Cited By ~ 1

Author(s):

S. Krishna Prasad ◽

Geetha G. Nair ◽

Gurumurthy Hegde ◽

Uma S. Hiremath ◽

C. V. Yelamaggad

Keyword(s):

Liquid Crystal ◽

Polymer Network

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Effect of Crosslinkers on Optical and Mechanical Behavior of Chiral Nematic Liquid Crystal Elastomers

Molecules ◽

10.3390/molecules26206193 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6193

Author(s):

Kyosun Ku ◽

Kyohei Hisano ◽

Kyoko Yuasa ◽

Tomoki Shigeyama ◽

Norihisa Akamatsu ◽

...

Keyword(s):

Liquid Crystal ◽

Polymer Network ◽

Molar Ratio ◽

Stimuli Responsive ◽

Breaking Strain ◽

Responsive Materials ◽

Sensor Applications ◽

Color Changes ◽

Chiral Nematic ◽

Liquid Crystal Elastomers

Chiral nematic (N*) liquid crystal elastomers (LCEs) are suitable for fabricating stimuli-responsive materials. As crosslinkers considerably affect the N*LCE network, we investigated the effects of crosslinking units on the physical properties of N*LCEs. The N*LCEs were synthesized with different types of crosslinkers, and the relationship between the N*LC polymeric system and the crosslinking unit was investigated. The N*LCEs emit color by selective reflection, in which the color changes in response to mechanical deformation. The LC-type crosslinker decreases the helical twisting power of the N*LCE by increasing the total molar ratio of the mesogenic compound. The N*LCE exhibits mechano-responsive color changes by coupling the N*LC orientation and the polymer network, where the N*LCEs exhibit different degrees of pitch variation depending on the crosslinker. Moreover, the LC-type crosslinker increases the Young’s modulus of N*LCEs, and the long methylene chains increase the breaking strain. An analysis of experimental results verified the effect of the crosslinkers, providing a design rationale for N*LCE materials in mechano-optical sensor applications.

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