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Thanks to your kindness and constant
support, PenMount has accumulated so many
market experiences that make PenMount grow.
PenMount brings the most stable and reliable
solutions to customers, and provides the
customers with efficient before- and
after-services. It has always been
PenMount's goal to rapidly and accurately
fix the problems that occur to customers.
A
resistive touch screen operates by the
"force" applied on it. PenMount occasionally
receives requests from customers asking if
it is possible to adjust the sensitivity of
a resistive touch screen through the
controller. To this question, we'd like to
raise another question in reply: what has
decided the sensitivity of a resistive touch
screen? Is it the controller or the touch
screen? In this issue of PenMount Bulletin,
we will make it clarified that the operation
of a resistive touch screen actually depends
on its constituent materials and its design.
A
touch screen operates by the force applied
on it. The force that makes the touch screen
work is the so called “sensitivity” of a
touch screen. In the following, we will
detail “sensitivity” in three phases :
(A). See the figure below. It shows the
state before force is applied to the touch
screen. The finger is simply placed on the
touch screen. The finger contacts the touch
screen surface, but ITO film and ITO glass
haven't contacted each other. No action is
triggered since the two electrical
conductive layers aren't pressed together
and no voltage gradient is caused.
(B). When force is gradually applied to the
touch screen, the upper ITO film layer is
pressed but isn't fully pressed to the
bottom ITO glass, and therefore the ITO film
and ITO glass are only slightly contacting
each other (due to uneven force
application). The rise and fall of
resistance are great at this moment. This is
the moment when signals haven't reached
stability, and also the moment some users
might mistakenly think as a time to adjust
the sensitivity. We'd like to clarify that
if the controller receives and sends out
these unstable signals, the touched position
detected will be wrong. However, PenMount
has overcome such problem by filtering the
unstable signals when signals haven't got
stable yet.
(C). When the force applied increases to
certain extent, say 10 g or more, the ITO
film and ITO glass are steadily contacted
and signals are stable. The controller
receives normalized signals.
A
regular touch on the touch screen is usually
a combination of the 3 phases mentioned
above. For example, the line drawn on the
touch screen with your finger pulp breaks
easily. This is mainly due to 2 reasons. On
one hand, your finger pulp, the contact
area, is big. The bigger the contact area
is, the smaller the pressure is. On the
other hand, the angle of your operating
finger isn't always consistent. Whether due
to the incomplete contact between ITO glass
and ITO film as mentioned in (B) or due to
lack of contact between ITO glass and ITO
film as mentioned in (A), PenMount drivers
ensure you the best touch experiences by the
optimized sensitivity of the touch screen.
All of PenMount's touch software / hardware
series are designed meeting markets demands.
If you feel any particular requirements for
any individualized product specification, we
are ready to fully assist you in the
development. The software / hardware
information and drivers of PenMount
standards are available on PenMount website
at
www.salt.com.tw
and
www.penmount.com.
And if you should have any comment, please
also feel free to write us at
salt@salt.com.tw
or
penmount@seed.net.tw. |
