FIELD: medicine. SUBSTANCE: method involves making investigation in two stages with stochastically localized (randomized) optotypes, which angular sizes are above threshold, shown to a testee at the first stage. Minimum vision analyzer load is to be applied and general psychophysical fatigue is studied within the framework of this stage. The same optotypes are shown to the testee at the second stage. The optotypes are of smaller angular sizes so that maximum vision analyzer load is applied to the vision analyzer. Optotypes positions vary with stage to exclude possibility for a testee to remember the position of a given optotype. Total fatigue degree is determined at the second stage that includes both psychophysical and visual fatigue. Visual fatigue degree is determined from difference of time spent at the first and the second investigation stage. EFFECT: differentiated psychophysical and visual fatigue types; high accuracy in evaluating visual fatigue degree. 1 dwg, 1 tbl
