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The need for tools that can assist in evaluating visual function is an essential and a growing requirement as lasers on the
modern battlefield mature and proliferate. The requirement for rapid and sensitive vision assessment under field
conditions produced the USAMRD Aidman Vision Screener (AVS), designed to be used as a field diagnostic tool for
assessing laser induced retinal damage. In this paper, we describe additions to the AVS designed to provide a more
sensitive assessment of laser induced retinal dysfunction. The AVS incorporates spectral LogMar Acuity targets without
and with neural opponent chromatic backgrounds. Thus, it provides the capability of detecting selective photoreceptor
damage and its functional consequences at the level of both the outer and inner retina. Modifications to the original
achromatic AVS have been implemented to detect selective cone system dysfunction by providing LogMar acuity
Landolt rings associated with the peak spectral absorption regions of the S (short), M (middle), and L (long) wavelength
cone photoreceptor systems. Evaluation of inner retinal dysfunction associated with selective outer cone damage
employs LogMar spectral acuity charts with backgrounds that are neurally opponent. Thus, the AVS provides the
capability to assess the effect of selective cone dysfunction on the normal neural balance at the level of the inner retinal
interactions. Test and opponent background spectra have been optimized by using color space metrics. A minimal
number of three AVS evaluations will be utilized to provide an estimate of false alarm level.
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