|
Background
LC-TEC DISPLAYS’ modern cleanroom environment has a total area of 270m2
and houses a second-generation STN-LCD production-line with a high degree of
automisation. This allows for both high volume manufacturing together with
good cell quality & yield.
Flexographic printer with vertical hot-plate (to left) and robotic
handling of substrates at the LC-TEC facility.
The maximum manufacturing throughput of the LCD production-line is one
(1) panel per minute for substrate dimensions 16 * 14 inches, yielding
approximately 150,000 panels/year for single-shift operation (8 hours per
day). However, spare manufacturing capacity currently gives LC-TEC
DISPLAYS a large degree of flexibility to also focus on the manufacturing
of smaller batches of test cells for specific R&D projects.
Furthermore, the large cleanroom area readily permits the installation of
new manufacturing & testing equipment that may be required for the
development of such projects.
With regard to the general manufacturing steps, the process steps are
as follows:
1) 14 x 16 inch glass substrates
ready-coated with ITO provided by our supplier.
2)
ITO patterning using wet chemical etching processes. Also applies to
optical-shutter devices where the ITO is removed from areas where the edges of
the glass substrates shall be bonded together in order to improve
adhesion, etc.
3) Insulation "hardcoat" layers and liquid crystal alignment "polyimide" layers
flexographically "off-set" printed onto the 14 x 16 inch
glass substrates. Many individual liquid crystal devices can be "grown" on each
14 x 16 inch substrate simultaneously (depending on size). High
temperature curing of the hardcoat & polyimde layers (typically in
excess of 300 degrees centigrade for several hours).
4)
Edge seal "gasket" screen-printed onto 14 x 16 inch substrates. Gasket
defines edges of each individual liquid crystal display device.
5)
Two pieces glass substrates assembled together into pairs to form a
"panel" and small distance "spacers" placed in-between the glass
substrates with an exact diameter for accurate cell-gap control. Gasket
adhesive thermally cured at typically 175 degrees centigrade
for several hours.
6) Individual liquid crystal display devices cut out of the 14 x 16
inch panel.
7) Individual liquid crystal display devices vacuum-filled with LC material through
a "filling-port" in the gasket edge seal.
8) Filled
liquid crystal display devices pressed together at room temperature in
order to squeeze out excess LC material and push the two glass substrates
together so that they make mechanical contact with the "spacers" present
in-between the glass plates.
9)
Filling-port sealed (end-seal) in order to prevent LC
material from leaking out.
These process steps are summarised in a diagram at the following link (Swedish).
A detailed technical description of the manufacturing capabilities
& volume capacities can be found at the following link (English).
Dry-spacer applicator (to right) in LC-Tec Display's manufactuirng
facilities.
Over the past several years, LC-TEC DISPLAYS has
focused on the development of the bistable Cholesteric Liquid Crystal
Display (Ch-LCD) technology for large signboard applications (18 inch
diagonal) and as such also has a wide experience in the assembling of
complete LCD modules such as the application of driver TAB’s to
LCD’s. LC-TEC DISPLAYS is now mainly focusing on contract
(LEGO)manufacturing of LCD components for third-party customers.
Layout of the LCD
production-line at the LC-Tec Displays AB's facility.
LC-TEC DISPLAYS has a wide experience in working with projects where
initial manufacturing volumes may be modest but where immediate quality
and yield are crucial and which also involve a high degree of R&D
input in order to fully develop and optimise both the liquid crystal
technology and manufacturing processes.
Reference customers include LightSpace Technologies Inc ., USA which
involved an 18 month project in order to fully-develop and bring to the
market their proprietary liquid crystal technology. This project was
successfully completed in July 2004 and has lead to the commercial launch
of their DepthCube® 3D-Monitor product.
Other reference customers include ECSIBEO AB, Sweden which has an ongoing active collaboration together
with LC-TEC DISPLAYS. Technicians from ECSIBEO are currently
based at the LC-TEC DISPLAYS facility in order to fully optimise the
process parameters required to manufacture high quality product based
on their propriety ECS® liquid crystal technology.
The sister-company LC-TEC AUTOMATION focuses on supplying LCD manufacturing
equipment and has a long experience in the design, manufacturing and
installation of equipment for modern LCD manufacturing. This partnership
has proved invaluable when both modifications of existing equipment
as well as the installation of new equipment has been required for
specific projects at the LC-TEC DISPLAYS facility.
Summary of key issues
LC-TEC DISPLAYS possesses a modern STN-LCD production-line with a high
degree of automation, offering high volume manufacturing together with
high quality & yield.
LC-TEC DISPLAYS’ cleanroom is 270m2 in area and consequently there is
room for the installation of new equipment that may be required for
specific projects.
Spare manufacturing capacity currently gives LC-TEC DISPLAYS the
flexibility to also focus on the manufacturing of smaller batches of test
cells for specific R&D projects where initial volumes may be modest
but where quality & yield are crucial.
LC-TEC DISPLAYS has a proven track record in commercialising projects
which contain a high degree of R&D content and require innovative
input.
LC-TEC DISPLAYS has a wide experience in the assembling of complete LCD
modules including the application of driver TAB’s to LCD’s.
The partnership together with the sister-company
LC-TEC AUTOMATION allows existing equipment to easily be modified as well as
the installation of new equipment for specific projects at the LC-TEC DISPLAYS
facility.
Products include liquid crystal optical shutters as well
as signboard & display products based both on the Ch-LCD technology as well as the direct-driven
TN technology. LC-TEC DISPLAYS also focuses on contract (LEGO)
manufacturing of LCD components for third-party customers.
©
Stephen Palmer 2005
|
