Pixel Size Requirements for Eye-Limited Flight Simulation
Abstract
The work described here was part of the Operational Based Vision Assessment (OBVA) program, the goal of which is to develop an eye-limited flight simulation laboratory to establish the relationship between clinical measures of visual capabilities and performance in simulated operationally relevant tasks. Because the design of such a high resolution flight simulation laboratory is ground breaking, and because angular pixel size is such a large cost driver, we used psychophysical methods to determine the pixel size specification. In the first series of experiments, the angular size required to identify the orientation of a triangle was estimated using angular pixel sizes ranging from 0.11 arcmin/pixel (eye-limited condition) to 4 arcmin/pixel (display-limited condition). From these data, along with an analysis of projector cost versus performance improvement, we concluded that 0.5 arcmin is a practical display pixel size specification. In the second experiment, we used a 0.5-arcmin display and a MetaVR IG to measure the range required to identify the aspect of an F-15 aircraft and found a strong correlation between the simulator results and clinical measures of acuity. Finally, because wide field of view simulators require multiple projectors and it is possible that multi-projector blending may lower performance, we also measured triangle orientation identification performance using the Survivability Performance Laboratory developed by Boeing. We found that current blending technology is sufficient to yield near eye-limited results in the blend zones. Taken together, these studies suggest that 0.5 arcmin/pixel is a practical specification for the OBVA simulator in that it provides a good cost benefit ratio and can be used to quantify the relationship between clinical measures of visual capabilities and performance in simulated operationally relevant tasks.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 13, 2010
- Accession Number
- ADA607627
Entities
People
- James P. Gaska
- James Rader
- Marc Winterbottom
- William Sweet
Organizations
- Air Force Research Laboratory