Automotive head-up displays (HUDs) are superior to conventional console displays in permitting recognition of the forward view and the displayed images. To test the superiority of HUD in visual optics, we have proposed the hypothesis that the peripheral field of vision plays an important role in allowing the driver to recognize displayed images while watching objects outside the vehicle. Using an experimental setup which can position HUD images three-dimensionally in space, we can verify the validity of this hypothesis based on a visual optical model.
One experimental result is that drivers can recognize some amount of information from the HUD in the peripheral field of vision. Another result is that the HUD being out of focus in the peripheral visual field can affect recognizability of HUD images. These results support the hypothesis. The model predicts that the recognizability of the HUD image will depend on depression angle. This is also confirmed qualitatively.