Specifications

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Surface Acoustic Wave Advantages
n Resolution - The resolution of
surface acoustic wave technology is
determined by the physical placement of the
reflector arrays. Typical resolution is 33
touch points per inch.
n Calibration - Since the reflector
arrays determining the touch location are
fixed in one place, surface acoustic wave
systems are not subject to the phenomenon
of sensor drift. The touch system needs only
to be aligned with its corresponding display.
n Z-axis - In addition to the typical x
and y coordinates, surface acoustic wave
systems can provide a z-axis component,
which is determined by the amount of
pressure applied to the sensor.
n Flexibility - Surface acoustic wave
touch systems are adaptable to a wide range
of displays without expensive custom fees.
n Transmissivity - Surface acoustic
wave touch systems typically have a
transmissivity of 92%.
Surface Acoustic Wave Disadvantages
n Stylus Requirements - Surface
acoustic wave touch systems require a soft,
energy-absorbing stylus to operate. A hard
stylus, such as a pen, will not absorb the
acoustic energy and will not be recognized
as a touch.
n Integration - Surface acoustic wave
touch system sensors typically require an
invasive integration to maximize the optical
quality and to reduce the chance of breaking
the glass overlay. This invasive integration
requires disassembly of the display and
(optionally) permanent optical bonding of
the sensor to the display.
n Sealability - Surface acoustic wave
touch systems cannot be sealed to NEMA 4
requirements and are susceptible to direct
exposure to water, dirt and other corrosives.
n Environmental Resistance - The
glass overlay of the surface acoustic wave
touch system sensor is susceptible to
breakage. An accumulation of liquids,
grease, dirt, etc., will absorb the acoustic
wave, rendering the system nonfunctional.