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Abstract
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OBJECTIVE: Evaluation of new vision technologies is an important public health concern as an increasing array of technologies designed to improve vision and quality of life make their way to the market. One important factor in evaluating these technologies is understanding the impact on complex visual tasks such as driving. Due to the need to provide a vision limited driving environment, meeting the requirements in a driving simulator has previously been a costly exercise; however, with the advances in display technology, more cost effect methods are now available. The objective of this paper is to assess the effectiveness of a new protocol and salable simulator configuration on detecting visual perform- ance differences in drivers.
METHODS: Utilizing the NADS-2 configured with a spatial resolution with respect to the subject of 0.5 minutes of arc and a glare generation device, visual performance pilot data was collected from 22 subjects wearing two different contact lenses. Each subject drove twice with each lens: once with glare from oncoming vehicles and once without glare. Over the course of the approximately 45 minute drive, subjects encountered a variety of road signs with various contrast ratios and information content, stationary hazards on the road surface, and moving hazards that cross the vehicles path. Additional scenario design and simulator configuration details will be provided in the paper. Subjects also underwent a series of traditional eye exams with each contract lens. De- pendent measures from the simulator include sign recognition accuracy and distance, detection and response to stationary hazards in the road, and reaction time and response to moving hazard on the roadway. Data was analyzed with respect to type of contact lens , corrected visual acuity and contrast sensitivity found with the two different contact lens designs.
RESULTS: Analysis of this data revealed that even with the small sample size, significant differences could be found between the two contract lenses and with and without glare. The most interesting result was that showing that with one contact lens, an incurring car was detected and responded to at a significantly smaller angular size. Additional differences between the lenses were also found for number of signs correctly identified as well as stationary hazards detected. Differences are also presented relative to other visual differences between subjects.
CONCLUSIONS: Based on the analysis of this pilot data, it is clear that this configuration can be used to assess differences in visual performance. The success with this configuration has already led to the design of a display system for integration into the NADS MiniSim that offers a very cost effective and easily deployable vision testing and research platform for studies to explore visual acuity, contrast sensitivity and glare. There are a number of important considerations that should be addressed for future research based on the findings from this study. One consideration is that with the use of a glare source associated with oncoming vehicles, timing of the vehicle relative to the signs and hazards is critical and scenario design must accommodate differences in when individual drivers will be engaging with the events. |