Construction

Transducers and reflector stripes on CRT face (outside of viewable area)

Same as iTouch but on clear glass overlay

Glass overlay with ITO coatings on front and back with silica overcoat

Light transmission

No overlay—100%

Typically 92%

Typically 85%

Reflection

No added reflection. Up to 80% less reflection than capacitive overlays on CRTs

Less than capacitive, more than iTouch

ITO coatings cause some additional reflections

Color purity

Perfect

Perfect

ITO coatings alter colors slightly

Clarity

No overlay—no antiglare needed

Same as clear glass. No noticeable degradation using USAF 1951 Resolution Chart

ITO and antiglare coatings can make images slightly less clear

Resolution

4095 x 4095
Z = 0–255

Same as iTouch

1024 x 1024 or greater
No Z

Accuracy

Standard deviation of error is less than 2 mm (less than ± 1%)

Same as iTouch

± 1.5%

Parallax

No added parallax

Parallax error caused by thickness of touchscreen glass and air gap

Same as IntelliTouch

Calibration

Stable

Stable

Can be less stable

Stability

Touch coordinates do not change with environment (temperature, humidity, surrounding metal, etc.)

Same as iTouch

Touch coordinates can possibly change with environment. May need recalibration periodically or when moved.

Sensitivity

Extremely sensitive

Very sensitive

Extremely sensitive

Speed

< 10 ms (recognizes fastest taps). Faster than capacitive in two-handed play.

Same as iTouch

<10 ms (recognizes fastest taps), but slower in two-handed play