Specifications

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Scanning Infrared Advantages
n Transmissivity - Because there is no
overlay covering the display, the transmissi-
vity of infrared touch systems is 100%.
n Stylus Requirements - Scanning
infrared touch systems require that the stylus
have a minimum diameter of 5/16”.
However, there are no limitations on the type
of material the stylus is made from.
n Calibration - Since the opto-
electronics determining the touch location
are fixed in one place, infrared touch systems
are not subject to sensor drift. They need
only to be aligned with the corresponding
display.
n Integration - Non-invasive scanning
infrared touch systems are available.
n Sealability - Scanning infrared
touch systems can be sealed to NEMA 4
requirements, preventing water and dirt from
penetrating the display electronics.
n Environmental Resistance - Since
scanning infrared touch systems do not
require an overlay (which can be broken),
they are less vulnerable to vandalism. Also,
they are relatively immune to shock and
vibration.
n Solid State - Infrared touch systems
are solid state technology and have no
moving mechanical parts. As such, they
have no physical sensor that can be abraded
or worn out with heavy use over time.
Scanning Infrared Disadvantages
n Resolution - Scanning infrared
touch systems typically provide a resolution
of eight touch points per inch. This does not
usually pose a problem when using a stylus
larger than 5/16” in diameter and touch
targets larger than 1/2” square.
n Parallax - Parallax occurs when a
touch is detected while the stylus is still
some small distance from the surface of the
display. For scanning IR touch systems,
parallax occurs because the invisible grid of
IR beams can be interrupted before actual
contact is made with the display. The
amount of parallax is dependent on the type
of integration and display type. Typically,
the flatter the display face, the lower the
amount of parallax.