Minimum colour differences required to recognize small objects on a colour c.r.t

Laboratory experiments to measure the eye´s colour sensitivity to small objects when viewing a typical colour c.r.t. display with an illuminated surround supplement the existing colour discrimination data and aid the development of metrics for evaluating the colour characteristics and visual performance with multicoloured displays for the variety of visual tasks in aerospace applications. The results are presented in the CIE colorimetric system similar to current standards used by the display engineer. The results show that very much larger colour differences are required for the recognition of small irregular objects than those assumed from the conventional colour discrimination data for detection or colour matching. A simple relationship to account for object size and background colour is suggested.