Contributed Session I: Wavefront analysis testing of protective eyewear

Abstract

The optical testing requirements of plano-protective eyewear in numerous national standards rely on subjective evaluation methods that are negatively impacted by factors such as accommodation, depth of focus, field of view and optical system resolving power differences. The aim of this study was to develop an objective method for testing the optical requirements of plano-protective eyewear.A Shack-Hartmann wavefront sensor and 542 nm collimated laser setup was used to build a Wavefront Analysis Optical Tester (WFAOT). The WFAOT was used to measure the refractive power of 9 calibration lenses and the left oculars of 36 military plano-protective eyewear. Subjective testing of the same samples was done using the telescope method described by American National Standard Institute (ANSI) Z87.1. A dependent t-test was used to evaluate the relationship between protective eyewear refractive powers before and after a two-week interval.SPSS 16 for Windows was used for all statistical analysis.The spherical powers of the verification lenses measured with WFAOT and ANSI Z87.1 telescope approach are shown in Table 1. There was no difference in refractive powers of the same protective eyewear measured before (M=-0.010, SD=0.018) and after (M=-0.009, SD=0.019) a two-week interval; t(35)= -0.466, p = 0.644.WFAOT is a refractive power measurement method comparable to the telescope approach proposed by ANSI Z87.1.