Can you trust your eyes? Researchers at Ford Motor Company's European Research Centre in Aachen, Germany, have developed a test to investigate to what extent colour differences are perceived by the human eye.

For example, when components of the same colour border each other in a vehicle interior but are made of different materials or textures, deviations in colour may occur. Ford researchers have now developed a new test methodology that can identify the degree to which the human eye is able to perceive these deviations.

The test device consists primarily of a high resolution, colour-calibrated monitor embedded into a housing where special lamps provide daylight conditions. In every run of the test, two colour surfaces appear with either no or different levels of colour deviation. The persons undergoing the test have to decide whether they perceive a colour deviation or not. 

The objective is to investigate the thresholds of human perception in order to establish additional indicators for quality control. Different textures of surfaces and materials impact the colouring and increase the probability for colour deviations.

In a further test procedure, experts who are responsible for colour selection in the vehicle or for quality control can train their eyes by trying to recreate colours in a computer programme. In this test, the test person looks at two plaques of different colour. By tuning the sliders to adjust for hue, saturation plus brightness and contrast, the person performing the test tries to match the colour of the second plaque to the colour of the first plaque. This enables the development of measureable and repeatable standards which previously had only been determined by subjective perception. The perceived differences are caused by different colour receptors in the human eye.

Dr. Carsten Starke, research engineer of the Ford European Research Centre, explained: "This multifunctional test has been tailored to our vehicle interior colours. We designed it as a global tool which delivers prompt results and can quickly be modified to new upcoming needs."

In an additional future application, this technology will help to assess the readability of information provided in a vehicle instrument cluster or on other vehicle displays. Standardised parameters, such as font type, size or colour contrast will lead to improvements in the readability of the vehicle's human machine interface system, and thus could contribute to enhanced vehicle safety.