About Touch screen technology
What is a touch screen?
A touch screen looks the same as any other screen in a
monitor,
kiosk,
etc and the unit can do as much as a standard unit can and more. It possesses an
extra piece of conductive glass placed over the front of the original screen as
well as an extra cable at the back. Once you have plugged them in and loaded up
the touch screen software drivers, you'll be ready to experience a whole new way
of working. Whenever a user touches the screen, the driver software will tell the
computer that they have 'left clicked' as you would with a mouse.
What types of touch screen technology are used in Protouch products?
There are several types of touch screen technology, and as a kiosk and touch screen
manufacturer Protouch predominately use the following:
Resistive touch screens
- A resistive touch screen
is composed of several flexible layers, the most important of which are two electrically
conductive layers, coated in transparent metal oxide and separated by a narrow gap.
- When a user touches the screen, the two metallic layers become connected and this
causes a change in the electrical current.
- The change in resistance to the current is measured and processed by the touch controller
which communicates this as a "mouse movement or click" to the computer's operating
system.
- Renowned as the most popular touch screen with a key advantage of being able to
be used with multiple pointing devices e.g. a gloved finger, finger nails, stylus
pens, etc.
-
The metal oxide coating and spacers may reduce the picture quality and brightness.
SAW touch screens
- Surface acoustic wave (SAW)
touch screens send sound waves across your screen surface to look for interruptions
caused by touch. This change in the ultrasonic waves registers the position of the
touch event and sends this information to the controller for processing.
- They are well suited to public access areas as, compared to resistive touch screens,
they have superior image clarity, resolution and higher light transmission.
- The SAW touch screens used in our
Xen Kiosks are made from extra-tough glass substrates that resist vandalism.
They have been chemically strengthened and meet the industry standard impact resistance
test of a 0.5kg, 500mm diameter ball dropped from a height of 1.3m.
- Because the technology cannot be sealed, it can be adversely affected by surface
contaminants and water, making it unsuitable for many industrial or commercial applications.
The contaminants can cause dead spots on the screen, requiring periodic cleaning
of the sensor and sometimes recalibration.
- These fast and sensitive touch screens work just as well with gloved hands and other
soft pointing devices as they do with your finger.
Optical touch screens
- Optical touch screens
use two optical sensors that work together to track the movement of any object close
to the surface.
- The touch registers just before the physical touch on the screen which means that
users can apply zero or light touch to the screen to initiate a response, and any
input device, so for example - a paintbrush, finger, pen, or stylus will all work.
- Once the sensors detect the interruption of an infra-red light source, the light
is emitted in a plane across the surface of the screen and can be either active
(infra-red LED) or passive (special reflective surfaces).
- At the heart of the system is a printed circuit controller board that receives signals
from the optical sensors. Its software then compensates for optical distortions
and triangulates the position of the touching object with extreme accuracy.
What is the difference between the various touch screen units?
Touch screen monitor
Touch screen monitors are desktop or wall mounted (stands and brackets available
for purchase) and require an external PC. Basically you are replacing your existing
computer screen with a touch screen so it will look and work as your normal computer
previously had. The
Geode touch screens are designed from the ground up to be touch
screen units. The
NECs we retro-fit (convert from standard display monitors into
touch screens by building in sensors).
All-in-one Touch PC
This is a complete system which has your PC housed within the touch screen monitor
and it can be desktop or wall mounted (stands and brackets available for purchase).
It is pretty much plug and play and does not require any link to any external PC.
Open Frame touch screens
These units are monitors but they have no bezel around them and are fixed within
existing apertures or kiosks. They are designed to be fixed behind an aperture so
that they are then flush with whatever housing you have incorporated them in to.
They require an external PC.
Kiosk
Kiosks are typically indoor, floor standing or wall mounted, stand alone, branded,
complete solutions. They can be customised with numerous accessories and perform
various functions. PCs are inbuilt and we also have outdoor kiosks.