Introduction
Today liquid crystals used in LCD displays are being used
in a wider range of products than ever before, prompting
the need for rapid liquid crystal application research. The
properties of liquid crystal materials used for LCDs are
evaluated using the data gained from voltage-capacitance
characteristics measurement. The measurement technique
presented in this application note describes how to take
best advantage of the E4980A and 4284A's powerful
features, when measuring capacitance while varying an ac
signal voltage applied to the liquid crystal material under
test. Capacitance characteristic measurements provide the
researcher with information on critical parameters, such
as the elastic constants which determines the threshold
voltage of the liquid crystal material and the acuteness of
its threshold characteristics.