Project Title:

High Temp. Piezo and Ferroelectric Liquid Crystal Polymers for

Displaytech, Inc.
2200 Central Avenue
Boulder, CO 80301

93-1  02.08 8933

High Temp. Piezo and Ferroelectric Liquid Crystal Polymers for
Wind Tunnel Use Tunnel Applications

Abstract:

The optical visualization of air or gas flow and the induced
stress field is crucial to many applications in aerodynamic
research. A new liquid crystal shear sensor based on
ferroelectric liquid crystals has been shown to respond in the
sub-millisecond time regime, making it an attractive candidate
for a fast response flow-field sensor. Two drawbacks are noted
for use of FLCs as field-flow sensors: 1) the active temperature
range of a typical FLC is usually below 100@C, and 2) due to low
viscosity, high air flows tend to remove the liquid crystal from
the test surface. In this proposal, we suggest an approach that
should dramatically improve performance of FLCs in both these
areas. By attachment of the properly selected FLC mesogen to a
polymer backbone, the smectic C range can be greatly raised, and
adhesion to the test surface markedly improved. In addition,
integration of high polarization mesogens should result in a
strong piezoelectric effect useful in pressure sensing
applications.

The new shear stress and pressure sensors can be used in
communications, medical instrumentation, mechanical field
measurements, and aircraft safety and design.

ferroelectric, FLC, piezoelectric, pressure sensor, field-flow
sensor