User Field Testing of Laser Protective Lenses

Abstract

A methodology for user field testing of military, laser protective lenses is described. It addresses the difficulty of testing the effects of their reduced light transmittance and color distortion when there is little or no control over the independent variables of illumination and environmental colors and contrasts. The thrust was to collect field data on more than 70 variables from over 250 soldiers, the rationale being that this “shotgun” approach would surface any critical problems. Moreover, if these field data were somewhat consistent with laboratory data, confidence could be placed in relative levels of soldier performance while wearing the lenses. No established methodology for such field testing existed, and a number of performance tasks had to be modified or constructed which were typical of military operations. The Farnsworth-Munsell 100-Hue Test was also conducted to investigate color discrimination ability while wearing the lenses. This test was intended to supplement other laboratory data and to serve as a reference for the field color distortion data. Analyses of the field test data validated the approach. The data base and procedures created will facilitate future research; there are clear indications of how to refine the tests now that the nature of response data has been more defined.