The recently developed dual-view touch screens, which are announced to be installed in cars in a near future, give rise to
completely new challenges in human-machine interaction. The automotive system should be able to identify if the driver
or the passenger is currently interacting with the touch screen to provide a correct response to the touch. The optical
devices, due to availability, acceptance by the users and multifunctional usage, approved to be the most appropriate
sensing technology for driver/passenger discrimination. In this work the prototypic optical user discrimination system is
implemented in the car simulator and evaluated in the laboratory environment with entirely controlled illumination.
Three tests were done for this research. One of them examined if the near-infrared illumination should be switched on
around the clock, the second one if there is a difference in discrimination performance between day, twilight and night
conditions, and the third one examined how the intensive directional lighting influences the performance of the
implemented user discrimination algorithm. Despite the high error rates, the evaluation results show that very simple
computer vision algorithms are able to solve complicated user discrimination task. The average error rate of 10.42%
(daytime with near-infrared illumination) is a very promising result for optical systems.