Effect of Haze in Advanced Laser Eye Protection Visors on Contrast Acuity

摘要

Laboratory tests were conducted to evaluate the effects of haze in FV-6MR and FV-7 advanced laser eye protection (ALEP) visors on vision. Preliminary results from early operational assessment (EOA) flight tests with the FV-6MR (night use) and FV-7 (day use) visors suggested that the current USAF standards for haze may not adequately predict either the user acceptance or mission compatibility. In addition to the ALEP visors, the standard USAF sun and clear visors were also tested for comparison purposes. A contrast acuity test served as the measure of visual performance. The results suggest that the effects of haze in the ALEP visors on vision were primarily on low contrast targets, decreasing visual acuity. Presence of a glare source, simulating the sun near the line of sight, enhanced the effects of haze, further decreasing visual performance suggest that higher luminance transmittance mounted visors performed better. Overall, however, the results suggest that the ALEP visors and the standard USAF sun visor performed similarly, indicating that neither the dye technology used in ALEP visors nor the selective filtering of visual spectrum for laser protection is unique. It is recommended that the haze requirement for all ALEP visors not be relaxed from the current USAF helmet visor standard of 2.0%.