Abstract
Two expriments are performed to determine the optimal white background color for the positive presentation mode of a VDT screen. The first investigates white background color preference without regard to task. One-hundred twenty-four subjects rate the white background colors of a VDT screen. In addition, twenty-three subjects adjust background color to their preferred color. The second experiment studies changes of preference of white background color after VDT work. Four operators perform data-entry task for three hours during five days, and the results indicate that the prefered white background has a correlated color temperature about 8000 K. This temperature represents a slight decrease along the black body locus after VDT work.
