1988-11-21
1990-08-07
Miller, Stanley D.
350336, 350332, 350346, 350331T, G02F 113
Patent
active
049462636
ABSTRACT:
In an optical device containing material which is dielectric wherein the device is switchable between an inactive relatively opaque state and an activated relatively transparent state in response to the application of a driving electric field of sufficiently low frequency, a problem may arise in that the switching time between the inactive-opaque state and the activated-transparent state is increased and/or the light transmissivity in the activated-transparent state is decreased when the device is at a relatively low temperature. This problem is alleviated by applying a heating electric field of sufficiently high frequency as to heat the dielectric material while not switching the device to the activated-transparent state thereby raising the temperature of the device to decrease the switching time between the inactive-opaque state and the activated-transparent state and/or to increase the light transmissivity in the activated-transparent state. The dielectric material may be a polymer film containing dispersed liquid crystal droplets.
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Smith George W.
VanSteenkiste Thomas H.
Vaz Nuno A.
Duong Tai V.
General Motors Corporation
Jaeger Tim G.
Miller Stanley D.
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