Conditions that Should Be Considered on IR touch screens in Worst-Case Scenarios

The specification of current IRON products is as follows:

In other words, the touch screen size should be 46 inches to 55 inches and the durability against sunlight interference is that MFA (Minimum Facing Angle) is 5 degrees at 150,000 Lux.

When the MFA is 5 degrees, the touch error would be estimated to 2.8 %.

(5 degrees/180 degrees)*100(%)=2.8(%)

2.8(%) * 12 hours = 0.366 hours

Though it is considerably decreased by calculation, the System Integrator should still be considered. Overall, the cost would be much lower compared to when the MFA is 30 degrees.

However, there is a situation here that can only explain the importance of MFA once again. In order to reduce the touch error by 5 degrees in the touch product adopting the IR technology, the touch sensor module should be installed at a position rotated by 5 degrees from the sun’s orbit. .

However, it is difficult to define the solar light interference in the outdoor environment only by the position of the regular sun described above and the interference of LOS. As the IR touch sensor module slope is entirely exposed by the reflector, the angle of incidence by the reflector must be considered to be at least 0 degrees. Examples of these reflectors are as follows: building glass, passing car glass, barbed reflections and other unforeseen countless random reflectors.

Of course, the reflected interference light from these reflectors is less than the amount directly introduced into the LOS with the sun. However, it is sufficient to account for the durability MFA mentioned above to zero degrees.

Therefore, IRON is currently under development with the goal of durability when the MFA is 0 degrees at 100,000 Lux. This is the condition that System Integrator can install touch systems at low cost, presenting interference- and disturbance- free touch systems from the outdoor and standard room.

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