HUMAN FACTORS EVALUATION OF VISUAL FIELD-OF-VIEW EFFECTS OF PARTIAL BINOCULAR OVERLAP DESIGNS IN HELMET-MOUNTED DISPLAYS

The Helmet Integrated Display Sight System (HIDSS) is a new binocular helmet-mounted display (HMD) under development by the U.S. Army for the RAH-66 Comanche helicopter. The HIDSS design uses a partial binocular overlap field-of-view (FOV) instead of a full overlap FOV where each of the two eyes sees the entire FOV. A full overlap FOV would have been an ideal optical display design configuration; however, technical and human factor considerations have limited the size of the FOV for each eye. The partial overlap display design overcomes this limitation by sharing the larger sensor FOV between the two eyes. Here a portion of the outside scene is displayed to both eyes, and each eye independently sees an additional portion. This has led to a number of visual human factor issues including the effect of this display design on the appearance of the FOV, on target detectability and on the binocular alignment of the two images. We review ongoing work conducted in our lab on the perceptual and performance effects of partial binocular overlap designs [1-8].