Online proceedings - EDA Publishing Association

11-13 May 2011, Aix-en-Provence, France
Figure 6. The relation ship between the gaps and PEDOT:PSS thicknesses. The
thickness of the PEDOT:PSS was tuned from 0 to 500 nm by changing the gap
from 0 o 300 μm.
Figure 9. Automatic looming machine. The pristine fiber and conductive and
dielectric film coated fibers were woven in the structure of plain weaving.
Figure 7. The relation ship between dies diameters and UV-curable polymer
thicknesses. The thickness of the UV curable adhesive was tuned from 0 to 45
μm by changing the dies diameter from 485 to 680 μm.
Figure 10 Woven fabric touch sensors. The PEDOT:PSS and UV-curable
adhesive-coated fibers were woven in the pitch of 5 cm. The sensor width and
length were 1.2 m and 3m, respectively.
Figure 8. The relationship between the traveling speed of fibers and
PEDOT:PSS thickness. Even if the traveling speed increased upto 50 m/min,
the thicknesses of PEDOT:PSS were almost same.
m/min. In case of UV curable adhesive, it was also
confirmed that the films were even until 50 m/min.
Therefore, the throughput of the fiber processing met the
requirements for the meter scale fabric sensors.
Ⅳ. WEAVING THE SENSOR FABRIC
The processed nylon fiber with PEDOT:PSS and
UV-curable adhesive was woven with automatic looming
machine, forming touch sensor sheet. The automatic
looming machine was made for looming the processed fibers.
The fibers were very week for friction during the weaving.
When the wefts were threaded in the warps, the wefts were
easily fiber got stuck with the warps, resulting in the
separation of the coated films. To solve the problems, the
machine had the linear actuator to move the wefts between
warps (figure 9).
The fibers were woven in the manner of plain weaving by
using the developed weaving machines. The coated fibers
were placed in the pitch of the 5 cm. The width of the fabric
is 1.2 m and the length was 3 m. Figure 10 shows the
fabricated fabric and the size is meter scale.
Ⅴ. CHARACTERIZATION OF FABRICATED TOUCH SENSOR
The fabricated sensor detects the capacitance change
between fiber and human finger. A human finger works as
an electrode for the capacitor formed with conductive
polymer-coated fibers because human is large-scale
conductor. In the capacitance measurement, the potential
was applied to the fiber and the flown current between fiber
and human was detected for estimating formed capacitors.
To detect the capacitance change between fiber and finger,
the capacitance measurement circuit was connected to the
fibers. Recently, capacitance measurement circuit was
embed on the conventional MCU for touch sensor on
portable electronic devices like i-phones. In our experiment
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