Professor of Chemistry Piotr Kaszynski and graduate student Bryan Ringstrand
New Type of Liquid Crystal Promises to Improve Performance of Digital Displays
Chemists at Vanderbilt University have created a new class of liquid crystals with unique electrical properties that could improve the performance of digital displays used on everything from digital watches to flat panel televisions.
The achievement, which is the result of more than five years of effort, is described by Professor of Chemistry Piotr Kaszynski and graduate student Bryan Ringstrand in a pair of articles published online on Sept. 24 and Sept. 28, 2010, in the Journal of Materials Chemistry.
"We have created liquid crystals with an unprecedented electric dipole, more than twice that of existing liquid crystals," says Kaszynski.
Electric dipoles are created in molecules by the separation of positive and negative charges. The stronger the charges and the greater the distance between them, the larger the electric dipole they produce.
In liquid crystals, the electric dipole is associated with the threshold voltage: the minimum voltage at which the liquid crystal operates.
Higher dipoles allow lower threshold voltages. In addition, the dipole is a key factor in how fast liquid crystals can switch between bright and dark states. At a given voltage, liquid crystals with higher dipoles switch faster than those with lower dipoles.