FIELD: medical equipment, namely apparatuses for investigating eyes functioning. SUBSTANCE: apparatus includes ramp voltage generator, voltage-frequency converter, source of light pulses, switch for setting generator in mode for generating rising voltage, switch for setting generator in mode for generating drop voltage, mode change-over switch, tumbler, single-shot multivibrator, gate circuit, counter and display. Ramp voltage generator, voltage-frequency converter and light pulse source are connected in series. Outlet of switches are connected with inlet of mode change-over switch. Outlet of tumbler at normally open contacts is connected with inlet of single-shot multivibrator; outlet of tumbler at normally closed contacts is connected with cleaning inlet of counter. Outlet of single-shot multivibrator is connected with second inlet of gate circuit whose first inlet is connected with outlet of voltage-frequency converter and whose outlet is connected with counting inlet of counter. Outlet of counter is connected with inlet of display. Apparatus also includes additional switch and second single-shot multivibrator whose outlet is connected with third inlet of mode change-over switch. EFFECT: enhanced accuracy of detecting critical frequency of light flashing. 2 dwg
