Project Title:

Ferroelectric Liquid Crystal Printhead

14.01-8933
912142
Ferroelectric Liquid Crystal Printhead
Displaytech, Inc.
2200 Central Avenue
Boulder
CO
80301
Mark A.
Handschy
303-449-8933
JSC
NAS9-18679
280

14.01-8933
912142

Abstract:

Ferroelectric Liquid Crystal Printhead
A linear array of light sources that can be individually switched with low-voltage,
low-power electrical signals will be developed. The approach will be to fabricate
a linear array of pixels using ferroelectric liquid crystals (FLC) that act as shutters
for a separate, unswitched light source. These fast-switching liquid crystals (50s
at 15 volts dc drive) can be pixelated with standard photolithographic techniques
to produce densities up to 500 pixels/inch for transmissive-mode and up to 4000 pixels/inch
for reflective-mode devices. For a long transmissive-mode device, utilization of
chip-on-glass technology or tape automated bonding will allow the driving electronics
to be mounted on the glass substrate used for the pixel electrodes, simplifying the
electrical interface. For a miniaturized reflective-mode device, implementation of
a hybrid spatial light modulator consisting of an FLC-layer coupled with a VLSI silicon
integrated circuit will eliminate the need for complicated electronic interconnects.
In either case, grey scale operation can be obtained by using a novel analog FLC
material or time-resolved addressing methods, and the use of color filters would
make full-color output feasible. Phase I will determine which linear array approach
is most feasible, demonstrate grey scale operation, and consider the options for
creating color hardcopy.
A linear array of 4096 individual light sources, with opportunity for both grey scale
and color operation, could be used to produce scanned, two-dimensional displays for
instrument panels, interactive terminals, and consoles. A specialized FLC/VLSI hybrid
array could also be used for a scanned two-dimensional private eye head mount display.
The FLC linear array would find use as the exposure unit in electrophotographic printing.
light source array, ferroelectric liquid crystals, spatial light modulator, printhead,
color hard copy, VLSI