Evaluation of Aircrew Low-Intensity Threat Laser Eye Protection

Mil Med. 2019 Mar 1;184(Suppl 1):593-603. doi: 10.1093/milmed/usy335.

Abstract

Prototype low-intensity threat laser eye protection (LIT-LEP) spectacles were evaluated for US Coast Guard (USCG) cockpits and night vision goggle compatibility. The impetus for interest in aviation LIT-LEP is driven in part by the fact that easily accessible 0.5-2.0 W high-power laser pointers exceed safety standards for direct on-axis viewing. A repeated-measures experimental design was used to assess LIT-LEP performance relative to a no-LEP control for the following tasks: Near- and far contrast acuity, night vision goggle far-contrast acuity, emissive and non-emissive light source color-vision screening, and USCG multifunctional display color symbol discrimination reaction time and accuracy. Near- and far-contrast acuity results demonstrated good LIT-LEP performance for typical in- and out-of-cockpit lighting conditions. Night vision goggle performance suffered marginally at only one contrast level (85%; 20/30 acuity line). Color vision test results showed good color balance in that S-, M-, and L-cone performance did not demonstrate a clinical diagnostic color defect for emissive or non-emissive light sources when wearing LIT-LEP. Color symbol discrimination reaction-time-task results based on inverse efficiency scores revealed that some non-primary flight display colors exhibited a combination of slower speed and decreased accuracy. The findings will contribute to an acquisition decision as well as guide future LEP designs.

Keywords: Acuity; Color Vision; Laser Eye Protection; Laser Veiling Glare; Visually-Mediated Performance.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aerospace Medicine / instrumentation*
  • Aerospace Medicine / methods
  • Equipment Design / standards
  • Eye Protective Devices / standards*
  • Humans
  • Lasers / adverse effects*
  • Military Personnel
  • Night Vision / physiology*
  • Reaction Time / physiology
  • Visual Acuity / physiology