Wide field of view helmet mounted display systems for helicopter simulation

Computer image generation for flight simulators: the Gabor approach

“…The visual system is spatially inhomogeneous in that only a small area near the center of the retina is sensitive to fine spatial detail, and in that the rate of both spatial sampling and processing decreases in all directions toward the visual periphery (Schwartz 1980;Kronauer and Zeevi 1985). In recognition of this property, flight simulators are now being designed to provide variable resolution either by partitioning the image into high-and low-resolution subfields such that a small, high-resolution portion of the display is always allocated to that portion of the image being fixated by the operator (Welch and Shenker 1984;Fischetti and Truxal 1985;Haworth et al 1988), or by optically distorting the display such that relatively more raster lines appear in the vicinity of the operator's fixation point (Diehl 1976). We describe here a further refinement of the variable resolution concept whereby visual images are generated using elementary functions having the form of frequency wavelets (see below), to which the human visual system is particularly sensitive (Watson et al 1983), and in combinations which reflect the most recent data on the changes in visual sensitivity across the retina (JOSA 1987;Geri et al 1989).…”